State of the research: 2026-10

Correction, 19 October 2026

This review was generated on 13 October 2026 and is kept below exactly as published. Since then, a check of every record against its source changed some of what it relies on:

• Unreviewed records. Most of the records this review counts and cites had only an automatic assessment. A check found about a quarter of the automatically extracted details false or unsupported, so the collection no longer publishes those records' study tier, population match, direction, mediation or funding until a person or a two-pass review has assessed them. Where this review gives those details for such a record, treat them as unchecked.
• Study facts. Sample sizes, follow-up periods, doses and summaries were corrected on many records, quote by quote against the source.
• Claim statuses. "GLP-1 receptor agonist treatment reduces the risk of developing dementia" is now Plausible, unproven (trend unclear), not Contradictory: the evoke trials treated established Alzheimer's disease and do not test prevention. "The cardiovascular benefit of GLP-1 receptor agonists is not explained by weight loss" stays Probable, with its trend now stable. Several claim rationales were corrected.

Each record page and claim page shows the current assessment. From November, the monthly review counts and cites reviewed records only.

Research-state review — 2026-10

Generated 2026-10-13T11:15:00+00:00 from the local evidence database. Every statement below cites a record number; open the record for provenance, funding and the full assessment. Auto-classified records are labelled as unreviewed in the database.

Scope reminder: this review assesses evidence about GLP-1 receptor agonists and related incretin therapies. It does not assess whether any therapy would benefit a specific person, and it does not recommend treatment.

Previous synthesis: 2026-09 (created 2026-09-13T14:18:53+00:00). New records since then are listed per topic.

Claim status overview

Claim	Status	Trend	Change since last synthesis
GLP-1 receptor agonists reduce alcohol and other substance use.	PRELIMINARY_SIGNAL	strengthening	unchanged
GLP-1 receptor agonists slow biological aging or extend healthspan in humans.	MECHANISTIC_ONLY	stable	unchanged
GLP-1 receptor agonists slow clinical progression of Alzheimer's disease.	NOT_SUPPORTED	weakening	unchanged
GLP-1 receptor agonist treatment reduces bone mineral density.	PRELIMINARY_SIGNAL	stable	unchanged
GLP-1 receptor agonists increase the risk of thyroid cancer in humans.	CONTRADICTORY	weakening	unchanged
GLP-1 receptor agonists reduce the incidence of obesity-associated cancers.	PRELIMINARY_SIGNAL	unclear	unchanged
The cardiovascular benefit of GLP-1 receptor agonists is not explained by weight loss.	PROBABLE	strengthening	unchanged
GLP-1 receptor agonists reduce cardiovascular events in people without obesity or established cardiovascular disease.	INSUFFICIENT_EVIDENCE	stable	unchanged
Incretin therapies improve outcomes in heart failure with preserved ejection fraction and obesity.	ESTABLISHED	stable	unchanged
GLP-1 receptor agonist therapy provides a net clinical benefit to healthy normal-weight adults aged 55-75.	INSUFFICIENT_EVIDENCE	stable	unchanged
GLP-1 receptor agonist treatment reduces the risk of developing dementia.	CONTRADICTORY	weakening	unchanged
Stopping GLP-1 therapy leads to regain of most lost weight and reversal of cardiometabolic improvements.	ESTABLISHED	stable	unchanged
GLP-1 receptor agonists cause serious gastrointestinal and biliary adverse events.	ESTABLISHED	stable	unchanged
GLP-1 receptor agonist treatment reduces systemic inflammatory markers beyond what can be explained by treatment-associated weight loss.	PLAUSIBLE_UNPROVEN	weakening	was PLAUSIBLE_UNPROVEN / strengthening
GLP-1 receptor agonists protect kidney function in people without diabetes.	PROBABLE	strengthening	unchanged
GLP-1-induced weight loss causes clinically meaningful loss of muscle mass or function.	PLAUSIBLE_UNPROVEN	stable	unchanged
Semaglutide improves liver histology in MASH with fibrosis.	ESTABLISHED	stable	unchanged
Semaglutide increases the risk of non-arteritic anterior ischaemic optic neuropathy (NAION).	EVIDENCE_OF_HARM	strengthening	unchanged
GLP-1 receptor agonists reduce osteoarthritis pain through mechanisms beyond weight loss.	INSUFFICIENT_EVIDENCE	stable	unchanged
GLP-1 receptor agonists slow progression of Parkinson's disease.	CONTRADICTORY	weakening	unchanged
GLP-1 receptor agonists increase suicidal ideation or suicide.	NOT_SUPPORTED	weakening	unchanged
GLP-1 receptor agonists alter the risk of autoimmune disease.	PRELIMINARY_SIGNAL	unclear	unchanged

Inflammation

• Records: 147 (human studies: 120). Evidence levels: HIGH 7, MODERATE 34, LOW 78, VERY_LOW 19, PRELIMINARY 4, NOT_RATED 5.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 24, VERY_INDIRECT 20, INDIRECT 102, PARTIAL 1. Records rated DIRECT or PARTIAL: 1.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Oral Semaglutide and Change in Cardiovascular Risk Factors in High-Risk Type 2 Diabetes: A Post Hoc Secondary Analysis of the SOUL Randomized Clinical Trial (JAMA cardiology, 2026; PMID 41879791; record #349) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: unclear
• Semaglutide and Exercise Function in Obesity-Related HFpEF: Insights From the STEP-HFpEF Program (JACC. Heart failure, 2025; PMID 41045908; record #376) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: no
• Atrial Fibrillation and Semaglutide Effects in Obesity-Related Heart Failure With Preserved Ejection Fraction: STEP-HFpEF Program (Journal of the American College of Cardiology, 2024; PMID 39217565; record #412) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: no

Strongest contradictory or null evidence:

• Long-Term Cardiovascular Outcomes of Glucagon-Like Peptide-1 Receptor Agonists in Non-diabetic Obesity: A Systematic Review and Meta-Analysis (Cureus, 2026; PMID 41658748; record #356) — MODERATE, Meta-analysis, direction mixed
• Efficacy and safety of semaglutide on weight loss in obese or overweight patients without diabetes: A systematic review and meta-analysis of randomized controlled trials (Frontiers in pharmacology, 2022; PMID 36188627; record #453) — MODERATE, Meta-analysis, direction harm
• Safety and efficacy of glucagon-like peptide-1 receptor agonists in patients with obstructive sleep apnea: a systematic review and meta-analysis of randomized controlled trials (European clinical respiratory journal, 2025; PMID 40144943; record #401) — MODERATE, Meta-analysis, direction mixed

New records since previous synthesis:

• Therapeutic modulation of the gut-brain axis in alcohol use disorder: A systematic review (Metabolism open, 2026; PMID 42750798; record #553)
• A GLP-1/apelin dual receptor agonist shows neuroprotective effects in the MPTP mouse model of Parkinson's disease (Biochemical pharmacology, 2026; PMID 42858820; record #905)
• Short-term clinical efficacy and recorded adverse events of semaglutide combined with dapagliflozin in patients with type 2 diabetes mellitus and chronic kidney disease (Medicine, 2026; PMID 42854065; record #911)
• Tirzepatide alleviates hepatic steatosis and inflammation in MASLD partly through suppression of macrophage Dectin-1/Syk/NF-κB signaling (European journal of pharmacology, 2026; PMID 42849688; record #915)
• Glucagon-like peptide-1 receptor agonists in hidradenitis suppurativa: A nationwide cohort study (Journal of the European Academy of Dermatology and Venereology : JEADV, 2026; PMID 42828450; record #805)
• Effects of semaglutide on kidney disease in type 2 diabetes: a randomized placebo-controlled trial (Nature medicine, 2026; PMID 42823485; record #810)
• Nephroprotective Effects of the Dual GCGR/GLP-1R Agonist Survodutide in Hypertension-Accelerated Diabetic Kidney Disease (Diabetes, obesity & metabolism, 2026; PMID 42823075; record #813)
• Oral semaglutide for weight loss and liver fibrosis in overweight and obesity: A randomized controlled trial (Indian journal of gastroenterology : official journal of the Indian Society of Gastroenterology, 2026; PMID 41066034; record #375)
• Real-world Evidence for Improvements in Inflammation and Anemia Biomarkers After the Initiation of GLP-1RA in Patients Receiving Hemodialysis (Kidney medicine, 2026; PMID 42787930; record #688)
• A Novel Dual Therapy for Diabetic Ischemic Heart Injury: Sinomenine and Liraglutide Restore Mitochondrial Homeostasis and Suppress Pyroptosis (FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 2026; PMID 42762056; record #543)

Claims in this domain:

• GLP-1 receptor agonist treatment reduces systemic inflammatory markers beyond what can be explained by treatment-associated weight loss. → PLAUSIBLE_UNPROVEN (weakening). Biomarker reductions in CRP and hs-CRP are consistent and large across trials in obesity, type 2 diabetes, heart failure with preserved ejection fraction and obstructive sleep apnoea. Whether any of that reduction survives accounting for weight loss is a separate question, and a documented search plus two-pass appraisal of every study that attempts to answer it leaves the question open. The two designs that separate drug from weight most cleanly - a weight-matched comparator, and the same model run with and without adjustment for weight change - are both null. The two results that support weight-independence come from papers publishing only the adjusted estimate, so the attenuation cannot be checked. The largest mediation analysis reports the mediated proportion and omits the residual direct effect. Earlier support for this claim rested on SELECT's early-timepoint and non-loser analyses, which are at high risk of bias because they are not locatable in the trial's protocol or analysis plan, and on one small weight-matched MCP-1 result, which two later comparisons contradict. No study exists in normal-weight people, and CRP is a biomarker, not a clinical outcome.

Unresolved questions:

• Are the anti-inflammatory effects of GLP-1 receptor agonists independent of weight loss, and do they occur in people without excess adiposity? (open)
• Is there clinically meaningful neuroprotection (dementia, Parkinson's) in humans? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Cardiovascular

• Records: 205 (human studies: 169). Evidence levels: HIGH 17, MODERATE 57, LOW 83, VERY_LOW 14, PRELIMINARY 14, NOT_RATED 20.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 47, INDIRECT 144, PARTIAL 1, VERY_INDIRECT 13. Records rated DIRECT or PARTIAL: 1.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Effects of GLP-1 receptor agonists on kidney and cardiovascular disease outcomes: a meta-analysis of randomised controlled trials (The lancet. Diabetes & endocrinology, 2025; PMID 39608381; record #34) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of randomised trials (The lancet. Diabetes & endocrinology, 2021; PMID 34425083; record #13) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (The New England journal of medicine, 2023; PMID 37952131; record #1) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes

Strongest contradictory or null evidence:

• Cardiovascular Outcomes with Tirzepatide versus Dulaglutide in Type 2 Diabetes (The New England journal of medicine, 2025; PMID 41406444; record #59) — HIGH, Randomized controlled trial, direction mixed
• Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial (Lancet (London, England), 2026; PMID 42815506; record #839) — HIGH, Randomized controlled trial, direction harm
• Long-Term Cardiovascular Outcomes of Glucagon-Like Peptide-1 Receptor Agonists in Non-diabetic Obesity: A Systematic Review and Meta-Analysis (Cureus, 2026; PMID 41658748; record #356) — MODERATE, Meta-analysis, direction mixed

New records since previous synthesis:

• EASL-EASD-EASO Guidance for the Use of Resmetirom and Semaglutide as MASH-Targeted Therapy (Journal of hepatology, 2026; PMID 42805503; record #851)
• Global Landscape and Thematic Evolution of Selective GLP-1 Receptor Agonists and GLP-1-Based Multi-Receptor Agonists in Type 2 Diabetes Mellitus: A Bibliometric Analysis (Endocrinology, diabetes & metabolism, 2026; PMID 42817068; record #837)
• Current review of glucagon-like peptide 1 receptor agonists and risk of nonarteritic anterior ischemic optic neuropathy (Journal of the Endocrine Society, 2026; PMID 42857401; record #955)
• Preconception incretin therapy reduces pregnancy and cardiometabolic outcomes in polycystic ovary syndrome (The Journal of clinical endocrinology and metabolism, 2026; PMID 42857939; record #931)
• Cardiovascular Risk in SELECT-Eligible MI Patients With Overweight or Obesity: The Western Denmark Heart Registry (JACC. Advances, 2026; PMID 42858539; record #930)
• Disparities in GLP-1RA and SGLT2i Uptake: a Systematic Review and an Equity-First Framework for Cardiovascular-Kidney-Metabolic Care (Current cardiology reports, 2026; PMID 42842171; record #944)
• Prevalence, risk factors and renoprotective treatment of chronic kidney disease among internal medicine outpatients at a Central European tertiary care centre: a cross-sectional study (BMJ open, 2026; PMID 42838586; record #946)
• Design and baseline characteristics of the CagriSema cardiovascular outcomes trial (REDEFINE 3) (American heart journal, 2026; PMID 42838477; record #947)
• GLP-1 receptor agonists for obstructive sleep apnea: a meta-analysis of randomized controlled trials (Sleep & breathing = Schlaf & Atmung, 2026; PMID 42837024; record #982)
• GLP-1 Receptor Agonists and Dual GIP/GLP-1 and Reduction in Major Cardiovascular Events: A Systematic Review and Network Meta-Analysis (preprint server, 2026; DOI 10.20944/preprints202610.0314.v1; record #991)

Claims in this domain:

• The cardiovascular benefit of GLP-1 receptor agonists is not explained by weight loss. → PROBABLE (strengthening). In SELECT (obesity + CVD, no diabetes) MACE reduction was consistent across baseline weight categories and showed no linear relationship with early weight loss; an estimated 33% of benefit was mediated via waist reduction. Class-wide CVOTs in type 2 diabetes show similar relative reductions with modest weight loss. This supports mechanisms beyond adiposity in people who already have obesity and atherosclerotic disease; it does not show benefit in people without excess adiposity.
• GLP-1 receptor agonists reduce cardiovascular events in people without obesity or established cardiovascular disease. → INSUFFICIENT_EVIDENCE (stable). No outcome trial has enrolled such a population. REWIND included T2D participants without prior CVD (benefit similar), but all had diabetes. The umbrella review found no significant MACE benefit in those without baseline CVD.
• Incretin therapies improve outcomes in heart failure with preserved ejection fraction and obesity. → ESTABLISHED (stable). STEP-HFpEF (symptoms, 6-minute walk, CRP) and SUMMIT (CV death or worsening HF, HR 0.62) in people with BMI >= 30. Not applicable to HFpEF without obesity; SELECT HF subgroup analysis also positive.

Unresolved questions:

• Are the cardiovascular effects independent of obesity? (partially_answered)
• Is there an effective dose for non-weight indications below weight-loss doses? (open)
• Does adding glucagon-receptor agonism (retatrutide, survodutide, mazdutide) change the benefit or harm profile relative to GLP-1 agonism alone, and would any of that carry over to normal-weight adults? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Kidney

• Records: 103 (human studies: 74). Evidence levels: HIGH 7, MODERATE 14, LOW 44, VERY_LOW 9, PRELIMINARY 6, NOT_RATED 23.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 36, INDIRECT 62, VERY_INDIRECT 5. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Effects of GLP-1 receptor agonists on kidney and cardiovascular disease outcomes: a meta-analysis of randomised controlled trials (The lancet. Diabetes & endocrinology, 2025; PMID 39608381; record #34) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of randomised trials (The lancet. Diabetes & endocrinology, 2021; PMID 34425083; record #13) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Oral Semaglutide and Cardiovascular Outcomes in High-Risk Type 2 Diabetes (The New England journal of medicine, 2025; PMID 40162642; record #35) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes

Strongest contradictory or null evidence:

• Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial (Lancet (London, England), 2026; PMID 42815506; record #839) — HIGH, Randomized controlled trial, direction harm
• Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes (The New England journal of medicine, 2016; PMID 27633186; record #11) — MODERATE, Randomized controlled trial, direction mixed
• Effects of Tirzepatide in Obesity-Related HFpEF by Sex: A Prespecified Secondary Analysis From the SUMMIT Trial (JACC. Heart failure, 2026; PMID 42417681; record #320) — MODERATE, Randomized controlled trial, direction mixed

New records since previous synthesis:

• EASL-EASD-EASO Guidance for the Use of Resmetirom and Semaglutide as MASH-Targeted Therapy (Journal of hepatology, 2026; PMID 42805503; record #851)
• Global Landscape and Thematic Evolution of Selective GLP-1 Receptor Agonists and GLP-1-Based Multi-Receptor Agonists in Type 2 Diabetes Mellitus: A Bibliometric Analysis (Endocrinology, diabetes & metabolism, 2026; PMID 42817068; record #837)
• Tirzepatide Initiation in Lithium-Treated Bipolar Disorder: Renal Biomarker Trajectories and Lithium Safety Signals Over 12 Months in a Real-World Cohort (Human psychopharmacology, 2026; PMID 42803597; record #860)
• Current review of glucagon-like peptide 1 receptor agonists and risk of nonarteritic anterior ischemic optic neuropathy (Journal of the Endocrine Society, 2026; PMID 42857401; record #955)
• Short-term clinical efficacy and recorded adverse events of semaglutide combined with dapagliflozin in patients with type 2 diabetes mellitus and chronic kidney disease (Medicine, 2026; PMID 42854065; record #911)
• Disparities in GLP-1RA and SGLT2i Uptake: a Systematic Review and an Equity-First Framework for Cardiovascular-Kidney-Metabolic Care (Current cardiology reports, 2026; PMID 42842171; record #944)
• Kidney Outcomes With GLP-1 Receptor Agonists and Tirzepatide Versus Finerenone in Type 2 Diabetes and Chronic Kidney Disease: A Real-World Cohort Study (Diabetes, obesity & metabolism, 2026; PMID 42842950; record #960)
• Prevalence, risk factors and renoprotective treatment of chronic kidney disease among internal medicine outpatients at a Central European tertiary care centre: a cross-sectional study (BMJ open, 2026; PMID 42838586; record #946)
• GLP-1 Receptor Agonists and Risk of Kidney Replacement Therapy and Health Care Utilization in Bipolar Disorder With Chronic Kidney Disease (The Journal of clinical psychiatry, 2026; PMID 42848524; record #958)
• Patterns of GLP-1 Receptor Agonist Initiation Compared With Other Glucose-Lowering and Anti-Obesity Therapies Among Older Adults (preprint server, 2026; DOI 10.64898/2026.09.29.26364340; record #990)

Claims in this domain:

• GLP-1 receptor agonists protect kidney function in people without diabetes. → PROBABLE (strengthening). FLOW established kidney protection in type 2 diabetes with CKD. In SELECT (no diabetes, obesity + CVD) a composite kidney endpoint was reduced (HR 0.78) and eGFR decline was slower; a meta-analysis found effects consistent with the diabetes trials. Evidence in normal-weight people without CVD does not exist. Body-composition changes did not distort GFR estimates in the small SMART trial.

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Dementia

• Records: 12 (human studies: 12). Evidence levels: HIGH 1, LOW 8, VERY_LOW 1, PRELIMINARY 2.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 10, PARTIAL 2. Records rated DIRECT or PARTIAL: 2.
• Confidence change since last synthesis: unchanged.

Strongest supporting evidence (benefit direction, by evidence level):

• Genetic Insights Into Protective Effects of GLP-1 Receptor Agonists on Stroke and Alzheimer Disease Across Ancestries (Neurology. Genetics, 2026; PMID 42812740; record #844) — LOW, Mendelian randomization, applicability INDIRECT, mediation possibly, industry funded: unclear
• Cardioprotective Glucose-Lowering Agents and Dementia Risk: A Systematic Review and Meta-Analysis (JAMA neurology, 2025; PMID 40193122; record #22) — LOW, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Higher semaglutide dose is associated with lower neuropsychiatric event incidence independent of weight loss (npj metabolic health and disease, 2026; PMID 42680805; record #195) — LOW, Retrospective cohort, applicability INDIRECT, mediation specifically_tested, industry funded: unclear

Strongest contradictory or null evidence:

• Efficacy and safety of oral semaglutide 14 mg (flexible dose) in early-stage symptomatic Alzheimer's disease (evoke and evoke+): two phase 3, randomised, placebo-controlled trials (Lancet (London, England), 2026; PMID 41865758; record #37) — HIGH, Randomized controlled trial, direction null
• Mapping the effectiveness and risks of GLP-1 receptor agonists (Nature medicine, 2025; PMID 39833406; record #20) — LOW, Retrospective cohort, direction mixed
• Liraglutide in mild to moderate Alzheimer's disease: a phase 2b clinical trial (Nature medicine, 2026; PMID 41326666; record #38) — LOW, Randomized controlled trial, direction mixed

New records since previous synthesis:

• Patterns of GLP-1 Receptor Agonist Initiation Compared With Other Glucose-Lowering and Anti-Obesity Therapies Among Older Adults (preprint server, 2026; DOI 10.64898/2026.09.29.26364340; record #990)
• Genetic Insights Into Protective Effects of GLP-1 Receptor Agonists on Stroke and Alzheimer Disease Across Ancestries (Neurology. Genetics, 2026; PMID 42812740; record #844)
• Benefits of sodium-glucose cotransporter 2 inhibitors versus glucagon-like peptide-1 receptor agonists in older patients with type 2 diabetes (Diabetes & vascular disease research, 2026; PMID 42808164; record #850)
• GLP-1 Receptor Agonists Versus DPP-4 Inhibitors and Incident Dementia Risk in COVID-19 Survivors with Type 2 Diabetes: A Target Trial Emulation Study (Drug design, development and therapy, 2026; PMID 42831108; record #928)

Claims in this domain:

• GLP-1 receptor agonist treatment reduces the risk of developing dementia. → CONTRADICTORY (weakening). Large observational cohorts in type 2 diabetes and a meta-analysis of RCT secondary outcomes suggest lower dementia incidence, but confounding by indication and healthy-user effects are plausible. The two phase 3 evoke trials found no slowing of progression in established early Alzheimer's disease, and ELAD (liraglutide) missed its primary endpoint. Prevention in cognitively normal people has not been tested in a randomized trial.

Unresolved questions:

• Is there clinically meaningful neuroprotection (dementia, Parkinson's) in humans? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Alzheimer's disease

• Records: 13 (human studies: 11). Evidence levels: HIGH 1, MODERATE 1, LOW 6, VERY_LOW 4, PRELIMINARY 1.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 8, VERY_INDIRECT 2, PARTIAL 2, UNKNOWN 1. Records rated DIRECT or PARTIAL: 2.
• Confidence change since last synthesis: increased (more higher-certainty records).

Strongest supporting evidence (benefit direction, by evidence level):

• Genetic Insights Into Protective Effects of GLP-1 Receptor Agonists on Stroke and Alzheimer Disease Across Ancestries (Neurology. Genetics, 2026; PMID 42812740; record #844) — LOW, Mendelian randomization, applicability INDIRECT, mediation possibly, industry funded: unclear
• GLP-1RA and SGLT2i Medications for Type 2 Diabetes and Alzheimer Disease and Related Dementias (JAMA neurology, 2025; PMID 40193118; record #21) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: no
• Associations of semaglutide with first-time diagnosis of Alzheimer's disease in patients with type 2 diabetes: Target trial emulation using nationwide real-world data in the US (Alzheimer's & dementia : the journal of the Alzheimer's Association, 2024; PMID 39445596; record #43) — VERY_LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: no

Strongest contradictory or null evidence:

• Efficacy and safety of oral semaglutide 14 mg (flexible dose) in early-stage symptomatic Alzheimer's disease (evoke and evoke+): two phase 3, randomised, placebo-controlled trials (Lancet (London, England), 2026; PMID 41865758; record #37) — HIGH, Randomized controlled trial, direction null
• Liraglutide in mild to moderate Alzheimer's disease: a phase 2b clinical trial (Nature medicine, 2026; PMID 41326666; record #38) — LOW, Randomized controlled trial, direction mixed
• Benefits of sodium-glucose cotransporter 2 inhibitors versus glucagon-like peptide-1 receptor agonists in older patients with type 2 diabetes (Diabetes & vascular disease research, 2026; PMID 42808164; record #850) — LOW, Retrospective cohort, direction mixed

New records since previous synthesis:

• Genetic Insights Into Protective Effects of GLP-1 Receptor Agonists on Stroke and Alzheimer Disease Across Ancestries (Neurology. Genetics, 2026; PMID 42812740; record #844)
• GLP-1R agonist semaglutide protects human forebrain organoids from cholesterol-induced neurotoxicity (Alzheimer's & dementia : the journal of the Alzheimer's Association, 2026; PMID 42805933; record #863)
• Comparative Risk of Nonarteritic Anterior Ischemic Optic Neuropathy Among Glucagon-Like Peptide-1 Receptor Agonists: An Integrated Safety and Mechanistic Analysis (Diabetes, obesity & metabolism, 2026; PMID 42768849; record #740)
• Benefits of sodium-glucose cotransporter 2 inhibitors versus glucagon-like peptide-1 receptor agonists in older patients with type 2 diabetes (Diabetes & vascular disease research, 2026; PMID 42808164; record #850)
• GLP-1 Receptor Agonists Versus DPP-4 Inhibitors and Incident Dementia Risk in COVID-19 Survivors with Type 2 Diabetes: A Target Trial Emulation Study (Drug design, development and therapy, 2026; PMID 42831108; record #928)
• Inflammatory proteins associated with Alzheimer's disease reduced by a GLP1 receptor agonist: a post hoc analysis of the EXSCEL randomized placebo controlled trial (Alzheimer's research & therapy, 2024; PMID 39358806; record #410)
• Exenatide exerts a potent antiinflammatory effect (The Journal of clinical endocrinology and metabolism, 2012; PMID 22013105; record #529)

Claims in this domain:

• GLP-1 receptor agonists slow clinical progression of Alzheimer's disease. → NOT_SUPPORTED (weakening). Two adequately powered phase 3 trials (evoke, evoke+) were negative on the primary clinical endpoint; ELAD phase 2b was negative on its primary endpoint.

Unresolved questions:

• Is there clinically meaningful neuroprotection (dementia, Parkinson's) in humans? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Parkinson's disease

• Records: 5 (human studies: 3). Evidence levels: HIGH 1, MODERATE 1, LOW 1, VERY_LOW 2.
• Applicability to healthy normal-weight adults 55-75: VERY_INDIRECT 2, PARTIAL 3. Records rated DIRECT or PARTIAL: 3.
• Confidence change since last synthesis: unchanged.

Strongest supporting evidence (benefit direction, by evidence level):

• Trial of Lixisenatide in Early Parkinson's Disease (The New England journal of medicine, 2024; PMID 38598572; record #9) — LOW, Randomized controlled trial, applicability PARTIAL, mediation unlikely, industry funded: no

Strongest contradictory or null evidence:

• Exenatide once a week versus placebo as a potential disease-modifying treatment for people with Parkinson's disease in the UK: a phase 3, multicentre, double-blind, parallel-group, randomised, placebo-controlled trial (Lancet (London, England), 2025; PMID 39919773; record #8) — HIGH, Randomized controlled trial, direction null
• Efficacy and safety of GLP-1 receptor agonists in Parkinson's disease: a systematic review and meta-analysis of randomized clinical trials (Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, 2026; PMID 42105060; record #51) — MODERATE, Meta-analysis, direction null

New records since previous synthesis:

• A GLP-1/apelin dual receptor agonist shows neuroprotective effects in the MPTP mouse model of Parkinson's disease (Biochemical pharmacology, 2026; PMID 42858820; record #905)
• The dual incretin agonist tirzepatide blunts nicotine-induced behaviours and neurochemistry in male mice (British journal of pharmacology, 2026; PMID 42805610; record #879)

Claims in this domain:

• GLP-1 receptor agonists slow progression of Parkinson's disease. → CONTRADICTORY (weakening). A phase 2 trial of lixisenatide showed less motor progression at 12 months, but the largest and longest trial (exenatide, phase 3, 96 weeks) found no benefit, and a 2026 meta-analysis of RCTs found no consistent benefit.

Unresolved questions:

• Is there clinically meaningful neuroprotection (dementia, Parkinson's) in humans? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Cognition

• Records: 17 (human studies: 15). Evidence levels: HIGH 2, MODERATE 1, LOW 7, VERY_LOW 4, PRELIMINARY 3.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 8, UNKNOWN 4, VERY_INDIRECT 2, PARTIAL 3. Records rated DIRECT or PARTIAL: 3.
• Confidence change since last synthesis: unchanged.

Strongest supporting evidence (benefit direction, by evidence level):

• Cardioprotective Glucose-Lowering Agents and Dementia Risk: A Systematic Review and Meta-Analysis (JAMA neurology, 2025; PMID 40193122; record #22) — LOW, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Higher semaglutide dose is associated with lower neuropsychiatric event incidence independent of weight loss (npj metabolic health and disease, 2026; PMID 42680805; record #195) — LOW, Retrospective cohort, applicability INDIRECT, mediation specifically_tested, industry funded: unclear
• GLP-1RA and SGLT2i Medications for Type 2 Diabetes and Alzheimer Disease and Related Dementias (JAMA neurology, 2025; PMID 40193118; record #21) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: no

Strongest contradictory or null evidence:

• Efficacy and safety of oral semaglutide 14 mg (flexible dose) in early-stage symptomatic Alzheimer's disease (evoke and evoke+): two phase 3, randomised, placebo-controlled trials (Lancet (London, England), 2026; PMID 41865758; record #37) — HIGH, Randomized controlled trial, direction null
• Exenatide once a week versus placebo as a potential disease-modifying treatment for people with Parkinson's disease in the UK: a phase 3, multicentre, double-blind, parallel-group, randomised, placebo-controlled trial (Lancet (London, England), 2025; PMID 39919773; record #8) — HIGH, Randomized controlled trial, direction null
• Neuropsychiatric Effects of Glucagon-Like Peptide-1 Receptor Agonists in Schizophrenia-Spectrum Disorders: A Systematic Review (Cureus, 2026; PMID 42725235; record #128) — MODERATE, Systematic review, direction mixed

New records since previous synthesis:

• Patterns of GLP-1 Receptor Agonist Initiation Compared With Other Glucose-Lowering and Anti-Obesity Therapies Among Older Adults (preprint server, 2026; DOI 10.64898/2026.09.29.26364340; record #990)
• Increasing Direct-to-Consumer Use of Semax and Selank Peptides Decoded from LLM-Curated Clinical Notes and Physician Adjudication (preprint server, 2026; DOI 10.20944/preprints202609.2396.v1; record #899)
• GLP-1 Receptor Agonists, Stroke, and Cognitive Outcomes: Systematic Review and Meta-Regression (preprint server, 2026; DOI 10.64898/2026.09.18.26363449; record #794)
• Effects of Semaglutide on Cognitive Function in People With HIV: A Randomized, Controlled Trial (Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2026; PMID 41098140; record #373)
• Benefits of sodium-glucose cotransporter 2 inhibitors versus glucagon-like peptide-1 receptor agonists in older patients with type 2 diabetes (Diabetes & vascular disease research, 2026; PMID 42808164; record #850)
• GLP-1 Receptor Agonists Versus DPP-4 Inhibitors and Incident Dementia Risk in COVID-19 Survivors with Type 2 Diabetes: A Target Trial Emulation Study (Drug design, development and therapy, 2026; PMID 42831108; record #928)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Osteoarthritis

• Records: 4 (human studies: 4). Evidence levels: MODERATE 3, PRELIMINARY 1.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 4. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: increased (more higher-certainty records).

Strongest supporting evidence (benefit direction, by evidence level):

• Once-Weekly Semaglutide in Persons with Obesity and Knee Osteoarthritis (The New England journal of medicine, 2024; PMID 39476339; record #7) — MODERATE, Randomized controlled trial, applicability INDIRECT, mediation likely, industry funded: yes

Strongest contradictory or null evidence:

• none recorded

New records since previous synthesis:

• Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity (The New England journal of medicine, 2026; PMID 42814954; record #868)

Claims in this domain:

• GLP-1 receptor agonists reduce osteoarthritis pain through mechanisms beyond weight loss. → INSUFFICIENT_EVIDENCE (stable). STEP 9 showed large pain reduction in people with obesity (mean BMI 40) alongside 13.7% weight loss. Weight loss itself relieves knee OA pain, and no analysis separated the two. No data in normal-weight people with OA.

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Rheumatoid / inflammatory disease

• Records: 9 (human studies: 9). Evidence levels: LOW 7, VERY_LOW 2.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 2, INDIRECT 7. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: unchanged.

Strongest supporting evidence (benefit direction, by evidence level):

• Comparative outcomes for tirzepatide versus glucagon-like peptide-1 receptor agonists in patients with inflammatory bowel disease: a national propensity matched study (Intestinal research, 2026; PMID 42717572; record #76) — LOW, Retrospective cohort, applicability UNKNOWN, mediation unknown, industry funded: unclear
• Effects of Semaglutide Treatment on Psoriatic Lesions in Obese Patients with Type 2 Diabetes Mellitus: An Open-Label, Randomized Clinical Trial (Biomolecules, 2025; PMID 39858442; record #404) — LOW, Prospective cohort, applicability INDIRECT, mediation possibly, industry funded: unclear
• Glucagon-like peptide-1 receptor agonist liraglutide therapy for psoriasis patients with type 2 diabetes: a randomized-controlled trial (The Journal of dermatological treatment, 2022; PMID 32962477; record #473) — LOW, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: unclear

Strongest contradictory or null evidence:

• Mapping the effectiveness and risks of GLP-1 receptor agonists (Nature medicine, 2025; PMID 39833406; record #20) — LOW, Retrospective cohort, direction mixed
• Autoimmune Disease Risk With GLP-1RA, DPP-4i, and SGLT2i Treatment in Patients With Diabetes (ACR open rheumatology, 2026; PMID 42415363; record #53) — VERY_LOW, Retrospective cohort, direction mixed
• GLP-1 Receptor Agonists in Dermatology: Prescribing Frameworks, Access, and the Emerging Pipeline (Clinics in dermatology, 2026; PMID 42777891; record #766) — VERY_LOW, Pharmacovigilance analysis, direction harm

New records since previous synthesis:

• GLP-1R expression and dermatological diseases: a mendelian randomization and real-world study (Endocrine, 2026; PMID 42842067; record #971)
• Glucagon-like peptide-1 receptor agonists in hidradenitis suppurativa: A nationwide cohort study (Journal of the European Academy of Dermatology and Venereology : JEADV, 2026; PMID 42828450; record #805)
• GLP-1 Receptor Agonists in Dermatology: Prescribing Frameworks, Access, and the Emerging Pipeline (Clinics in dermatology, 2026; PMID 42777891; record #766)
• Cardiovascular outcomes associated With GLP-1 and dual GLP-1/GIP receptor agonists in patients with type 2 diabetes and inflammatory bowel disease: A retrospective real-world cohort study (PloS one, 2026; PMID 42784582; record #692)
• Effects of Semaglutide Treatment on Psoriatic Lesions in Obese Patients with Type 2 Diabetes Mellitus: An Open-Label, Randomized Clinical Trial (Biomolecules, 2025; PMID 39858442; record #404)
• Glucagon-like peptide-1 receptor agonist liraglutide therapy for psoriasis patients with type 2 diabetes: a randomized-controlled trial (The Journal of dermatological treatment, 2022; PMID 32962477; record #473)

Claims in this domain:

• GLP-1 receptor agonists alter the risk of autoimmune disease. → PRELIMINARY_SIGNAL (unclear). A TriNetX target-trial emulation found no difference between GLP-1RA and SGLT2i; DPP-4i differed in both directions for specific diseases. Hypothesis-generating only.

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Muscle / sarcopenia

• Records: 15 (human studies: 9). Evidence levels: MODERATE 2, LOW 7, VERY_LOW 1, NOT_RATED 5.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 5, INDIRECT 8, VERY_INDIRECT 2. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: unchanged.

Strongest supporting evidence (benefit direction, by evidence level):

• Real-world effectiveness of 6-month tirzepatide therapy on body weight and composition in adults with overweight and obesity (Journal of diabetes and its complications, 2026; PMID 42805130; record #852) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: unclear
• Real-World Body Composition and Blood Pressure Changes Following Glucagon-Like Peptide 1 Receptor Agonist Initiation: A Causal Inference Study of Connected Device Data (Mayo Clinic proceedings. Digital health, 2026; PMID 42746268; record #614) — LOW, Retrospective cohort, applicability UNKNOWN, mediation unknown, industry funded: unclear

Strongest contradictory or null evidence:

• Apitegromab for lean mass preservation during tirzepatide-induced weight loss: a randomized, double-blind, placebo-controlled phase 2 trial (Nature medicine, 2026; PMID 42260100; record #47) — LOW, Randomized controlled trial, direction mixed
• Effects of Semaglutide on Body Composition and GFR: A Prespecified Analysis of the SMART Trial (Clinical journal of the American Society of Nephrology : CJASN, 2026; PMID 42308057; record #46) — LOW, Randomized controlled trial, direction mixed
• Low baseline HbA1c and reduced eGFR are associated with relatively unfavorable body recomposition after SGLT2 inhibitor therapy in type 2 diabetes (Frontiers in endocrinology, 2026; PMID 42723833; record #175) — LOW, Retrospective cohort, direction harm

New records since previous synthesis:

• EASL-EASD-EASO Guidance for the Use of Resmetirom and Semaglutide as MASH-Targeted Therapy (Journal of hepatology, 2026; PMID 42805503; record #851)
• Discovery of Fisetin as a potent and cell-active ACVR2A inhibitor (Bioorganic & medicinal chemistry letters, 2026; PMID 42801961; record #872)
• Real-world effectiveness of 6-month tirzepatide therapy on body weight and composition in adults with overweight and obesity (Journal of diabetes and its complications, 2026; PMID 42805130; record #852)
• GLP-1-based treatments and long-term clinical outcomes in MASLD amongst older adults: a retrospective cohort study (Age and ageing, 2026; PMID 42765724; record #746)
• Real-World Body Composition and Blood Pressure Changes Following Glucagon-Like Peptide 1 Receptor Agonist Initiation: A Causal Inference Study of Connected Device Data (Mayo Clinic proceedings. Digital health, 2026; PMID 42746268; record #614)
• Reduction of visceral fat by liraglutide is associated with ameliorations of hepatic steatosis, albuminuria, and micro-inflammation in type 2 diabetic patients with insulin treatment: a randomized control trial (Endocrine journal, 2017; PMID 27916783; record #498)

Unresolved questions:

• What happens to lean mass and muscle function in normal-weight users? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Lean-mass loss

• Records: 20 (human studies: 16). Evidence levels: HIGH 1, MODERATE 7, LOW 8, VERY_LOW 1, NOT_RATED 3.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 5, VERY_INDIRECT 1, INDIRECT 14. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Once-Weekly Semaglutide in Adults with Overweight or Obesity (The New England journal of medicine, 2021; PMID 33567185; record #42) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation not_applicable, industry funded: yes
• Effects of retatrutide on body composition in people with type 2 diabetes: a substudy of a phase 2, double-blind, parallel-group, placebo-controlled, randomised trial (The lancet. Diabetes & endocrinology, 2025; PMID 40609566; record #796) — MODERATE, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes
• Healthy Weight Loss Maintenance with Exercise, Liraglutide, or Both Combined (The New England journal of medicine, 2021; PMID 33951361; record #27) — MODERATE, Randomized controlled trial, applicability INDIRECT, mediation not_applicable, industry funded: partial

Strongest contradictory or null evidence:

• Treatment strategies for functional hypogonadism in obese men: a systematic review and network meta-analysis (The journal of sexual medicine, 2026; PMID 42704281; record #204) — MODERATE, Meta-analysis, direction mixed
• Bone Health After Exercise Alone, GLP-1 Receptor Agonist Treatment, or Combination Treatment: A Secondary Analysis of a Randomized Clinical Trial (JAMA network open, 2024; PMID 38916894; record #26) — MODERATE, Randomized controlled trial, direction harm
• The Impact of Glucagon-like Peptide-1 (GLP-1) Receptor Agonists on Body Composition in Individuals with Overweight and Obesity: A Systematic Review and Meta-Analysis (Journal of clinical medicine, 2026; PMID 42739822; record #616) — MODERATE, Meta-analysis, direction harm

New records since previous synthesis:

• Fat and lean mass changes during incretin-based therapy with structured exercise and nutritional support: A retrospective real-world pilot study (Obesity pillars, 2026; PMID 42820241; record #867)
• An RNA thermogenic therapy to preserve lean mass and enhance metabolic health during GLP-1 weight loss (Proceedings of the National Academy of Sciences of the United States of America, 2026; PMID 42789307; record #759)
• Real-world effectiveness of 6-month tirzepatide therapy on body weight and composition in adults with overweight and obesity (Journal of diabetes and its complications, 2026; PMID 42805130; record #852)
• The Impact of Glucagon-like Peptide-1 (GLP-1) Receptor Agonists on Body Composition in Individuals with Overweight and Obesity: A Systematic Review and Meta-Analysis (Journal of clinical medicine, 2026; PMID 42739822; record #616)
• Low Preoperative Free Triiodothyronine, Particularly in Females, Is Associated With Reduced Weight Loss and Diabetes Remission After Bariatric Surgery in Euthyroid Adults (Diabetes/metabolism research and reviews, 2026; PMID 42733963; record #620)
• Effects of retatrutide on body composition in people with type 2 diabetes: a substudy of a phase 2, double-blind, parallel-group, placebo-controlled, randomised trial (The lancet. Diabetes & endocrinology, 2025; PMID 40609566; record #796)
• Combination of exercise and GLP-1 receptor agonist treatment reduces severity of metabolic syndrome, abdominal obesity, and inflammation: a randomized controlled trial (Cardiovascular diabetology, 2023; PMID 36841762; record #446)
• Effect of short-acting exenatide administered three times daily on markers of cardiovascular disease in type 1 diabetes: A randomized double-blind placebo-controlled trial (Diabetes, obesity & metabolism, 2020; PMID 32543021; record #474)
• Exenatide affects circulating cardiovascular risk biomarkers independently of changes in body composition (Diabetes care, 2010; PMID 20424219; record #533)

Claims in this domain:

• GLP-1-induced weight loss causes clinically meaningful loss of muscle mass or function. → PLAUSIBLE_UNPROVEN (stable). Lean-mass loss accompanies weight loss with these drugs (roughly 15-60% of weight lost across studies), including in trials adding myostatin inhibition to preserve it. Whether this translates into reduced strength, function or fracture risk is not established; reviews argue it is often proportionate to weight loss. Data in normal-weight or older adults, who have less fat to lose and higher sarcopenia risk, are absent.

Unresolved questions:

• What is the risk-benefit balance in normal-weight adults aged 55-75? (open)
• What happens to lean mass and muscle function in normal-weight users? (open)
• Does adding glucagon-receptor agonism (retatrutide, survodutide, mazdutide) change the benefit or harm profile relative to GLP-1 agonism alone, and would any of that carry over to normal-weight adults? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Bone

• Records: 10 (human studies: 9). Evidence levels: MODERATE 2, LOW 5, VERY_LOW 2, PRELIMINARY 1.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 3, INDIRECT 6, VERY_INDIRECT 1. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: unchanged.

Strongest supporting evidence (benefit direction, by evidence level):

• Investigating the Relationship Between Glucagon-Like Peptide-1 Receptor Agonist Use and Incidence of Vertebral Fractures in Female Patients Aged Over 50 Years With Osteoporosis: A Propensity-Matched Analysis (Clinical spine surgery, 2026; PMID 42683541; record #184) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: unclear

Strongest contradictory or null evidence:

• Bone Health After Exercise Alone, GLP-1 Receptor Agonist Treatment, or Combination Treatment: A Secondary Analysis of a Randomized Clinical Trial (JAMA network open, 2024; PMID 38916894; record #26) — MODERATE, Randomized controlled trial, direction harm
• Vagal activity related events and glucagon-like peptide-1 receptor agonists (European heart journal. Cardiovascular pharmacotherapy, 2026; PMID 42709513; record #202) — LOW, Retrospective cohort, direction null
• Preoperative GLP-1 receptor agonist use and outcomes after total hip arthroplasty: a matched cohort study (Hip international : the journal of clinical and experimental research on hip pathology and therapy, 2026; PMID 42725550; record #199) — LOW, Retrospective cohort, direction harm

New records since previous synthesis:

• Genetically Proxied GIP-GIPR Pathway Perturbation and Fracture Risk (Diabetes, obesity & metabolism, 2026; PMID 42811415; record #869)
• Fracture-Centred Skeletal Reporting Profiles of Glucose-Lowering Drug Classes in FAERS and JADER: Cross-Database and Regional Reporting-Context Analyses (Diabetes, obesity & metabolism, 2026; PMID 42734024; record #619)
• GLP-1-based treatments and long-term clinical outcomes in MASLD amongst older adults: a retrospective cohort study (Age and ageing, 2026; PMID 42765724; record #746)

Claims in this domain:

• GLP-1 receptor agonist treatment reduces bone mineral density. → PRELIMINARY_SIGNAL (stable). In S-LiTE, liraglutide alone was associated with lower hip and spine BMD than exercise alone after a year of weight maintenance; combining exercise with liraglutide preserved BMD. Fracture outcomes are not available. Effect likely reflects weight loss rather than a direct drug effect, but this was not separated.

Unresolved questions:

• What is the risk-benefit balance in normal-weight adults aged 55-75? (open)
• What happens to lean mass and muscle function in normal-weight users? (open)
• What happens with use measured in decades rather than years? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Liver / MASH

• Records: 37 (human studies: 24). Evidence levels: HIGH 1, MODERATE 5, LOW 17, VERY_LOW 11, NOT_RATED 3.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 7, VERY_INDIRECT 10, INDIRECT 20. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Phase 3 Trial of Semaglutide in Metabolic Dysfunction-Associated Steatohepatitis (The New England journal of medicine, 2025; PMID 40305708; record #6) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes
• Tirzepatide Beyond Diabetes and Obesity: Systematic Review and Meta-Analysis of Multisystem Therapeutic Benefits (Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists, 2026; PMID 42061648; record #341) — MODERATE, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Comparative Efficacy of Promising Targets in the Treatment of Metabolic Dysfunction-associated Steatotic Liver Disease and Steatohepatitis: A Systematic Review and Network Meta-analysis (Journal of clinical and translational hepatology, 2026; PMID 42724131; record #214) — MODERATE, Meta-analysis, applicability UNKNOWN, mediation unknown, industry funded: unclear

Strongest contradictory or null evidence:

• Incremental effects of SGLT2 inhibitors, GLP-1 receptor agonists, and pioglitazone in type 2 diabetes and MASLD across Asian study settings: a systematic review and meta-analysis (Frontiers in endocrinology, 2026; PMID 42745769; record #627) — MODERATE, Meta-analysis, direction null
• Incretin-Based Therapies Versus Bariatric and Metabolic Surgery for Obesity and Type 2 Diabetes Mellitus: A Head-to-Head Systematic Review of Glycaemic, Cardiovascular, Hepatic, Weight, and Quality-of-Life Outcomes (Cureus, 2026; PMID 42677221; record #169) — MODERATE, Systematic review, direction mixed
• Data-Driven Multidimensional Clinical Phenotypes and Longitudinal Changes in Type 2 Diabetes Mellitus: A Retrospective Cohort Study (Biomedicines, 2026; PMID 42792646; record #680) — LOW, Retrospective cohort, direction null

New records since previous synthesis:

• EASL-EASD-EASO Guidance for the Use of Resmetirom and Semaglutide as MASH-Targeted Therapy (Journal of hepatology, 2026; PMID 42805503; record #851)
• Tirzepatide alleviates hepatic steatosis and inflammation in MASLD partly through suppression of macrophage Dectin-1/Syk/NF-κB signaling (European journal of pharmacology, 2026; PMID 42849688; record #915)
• An RNA thermogenic therapy to preserve lean mass and enhance metabolic health during GLP-1 weight loss (Proceedings of the National Academy of Sciences of the United States of America, 2026; PMID 42789307; record #759)
• Semaglutide, independent of weight loss, attenuates cardiac and hepatic remodelling in experimental heart failure with preserved ejection fraction (European heart journal, 2026; PMID 42830666; record #953)
• Nephroprotective Effects of the Dual GCGR/GLP-1R Agonist Survodutide in Hypertension-Accelerated Diabetic Kidney Disease (Diabetes, obesity & metabolism, 2026; PMID 42823075; record #813)
• Oral semaglutide for weight loss and liver fibrosis in overweight and obesity: A randomized controlled trial (Indian journal of gastroenterology : official journal of the Indian Society of Gastroenterology, 2026; PMID 41066034; record #375)
• Weight Reduction Heterogenicity and Mediators of GLP-1RAs and Dual Agonists for Individuals With Obesity: A Meta-Analysis (Clinical obesity, 2026; PMID 42733128; record #630)
• Comparative outcomes of GLP-1 receptor agonist and SGLT2 inhibitor users after liver transplantation: An emulated target trial (Metabolism: clinical and experimental, 2026; PMID 42810614; record #848)
• Hypothalamic obesity in pediatric vs. adult craniopharyngioma: mechanisms, management, and cardiometabolic outcomes (Pituitary, 2026; PMID 42801380; record #864)
• Outcomes of GLP-1 Receptor Agonist Therapy after Liver Transplantation in Patients with Type 2 Diabetes: A Real-World Cohort Study (Journal of gastrointestinal and liver diseases : JGLD, 2026; PMID 42803248; record #882)

Claims in this domain:

• Semaglutide improves liver histology in MASH with fibrosis. → ESTABLISHED (stable). ESSENCE part 1 (n=800 analysed): steatohepatitis resolution 62.9% vs 34.3%, fibrosis improvement 36.8% vs 22.4% at 72 weeks. Participants had MASH and mostly obesity; benefit may be partly weight mediated. Clinical outcomes (cirrhosis, decompensation) awaited in part 2.

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Immune function

• Records: 36 (human studies: 23). Evidence levels: MODERATE 3, LOW 16, VERY_LOW 8, PRELIMINARY 1, NOT_RATED 8.
• Applicability to healthy normal-weight adults 55-75: VERY_INDIRECT 6, INDIRECT 13, UNKNOWN 17. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Outcomes of GLP-1 Receptor Agonist Therapy after Liver Transplantation in Patients with Type 2 Diabetes: A Real-World Cohort Study (Journal of gastrointestinal and liver diseases : JGLD, 2026; PMID 42803248; record #882) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: unclear
• Effectiveness of Adding GLP-1 Receptor Agonists to SGLT2 Inhibitor Therapy in Chronic Kidney Disease: A Population Based Study (Diabetes, obesity & metabolism, 2026; PMID 42802242; record #854) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: no
• GLP-1R expression and dermatological diseases: a mendelian randomization and real-world study (Endocrine, 2026; PMID 42842067; record #971) — LOW, Mendelian randomization, applicability UNKNOWN, mediation specifically_tested, industry funded: no

Strongest contradictory or null evidence:

• Do Preoperative Glucagon-Like Peptide-1 Receptor Agonists Influence Lumbar Fusion Outcomes? A Systematic Review and Meta-Analysis (International journal of spine surgery, 2026; PMID 42754392; record #639) — MODERATE, Meta-analysis, direction harm
• Safety and Glycemic Efficacy of Perioperative Liraglutide in Cardiac Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials (Cardiology in review, 2026; PMID 42693519; record #181) — MODERATE, Meta-analysis, direction null
• Cardiorenal Protection in Type 2 Diabetes: A Systematic Review Comparing Glucagon-Like Peptide-1 Receptor Agonists and Sodium-Glucose Cotransporter-2 Inhibitors (Cureus, 2026; PMID 42724505; record #130) — MODERATE, Systematic review, direction mixed

New records since previous synthesis:

• Tirzepatide alleviates hepatic steatosis and inflammation in MASLD partly through suppression of macrophage Dectin-1/Syk/NF-κB signaling (European journal of pharmacology, 2026; PMID 42849688; record #915)
• Adverse Oral and Salivary Effects Associated With Glucagon-Like Peptide-1 Receptor Agonists: Clinical Insights (Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology, 2026; PMID 42843413; record #970)
• GLP-1R expression and dermatological diseases: a mendelian randomization and real-world study (Endocrine, 2026; PMID 42842067; record #971)
• Effects of semaglutide on kidney disease in type 2 diabetes: a randomized placebo-controlled trial (Nature medicine, 2026; PMID 42823485; record #810)
• Comparative outcomes of GLP-1 receptor agonist and SGLT2 inhibitor users after liver transplantation: An emulated target trial (Metabolism: clinical and experimental, 2026; PMID 42810614; record #848)
• Effectiveness of Adding GLP-1 Receptor Agonists to SGLT2 Inhibitor Therapy in Chronic Kidney Disease: A Population Based Study (Diabetes, obesity & metabolism, 2026; PMID 42802242; record #854)
• Outcomes of GLP-1 Receptor Agonist Therapy after Liver Transplantation in Patients with Type 2 Diabetes: A Real-World Cohort Study (Journal of gastrointestinal and liver diseases : JGLD, 2026; PMID 42803248; record #882)
• Safety of Sodium/Glucose Cotransporter 2 Inhibitors in Patients With Type 2 Diabetes and CKD (American journal of kidney diseases : the official journal of the National Kidney Foundation, 2026; PMID 42767321; record #755)
• Do Preoperative Glucagon-Like Peptide-1 Receptor Agonists Influence Lumbar Fusion Outcomes? A Systematic Review and Meta-Analysis (International journal of spine surgery, 2026; PMID 42754392; record #639)
• Obstructive sleep apnea, GLP-1 receptor agonist pharmacotherapy, and the oral microbiome: competing biological influences and implications for oral health monitoring (Clinical oral investigations, 2026; PMID 42734711; record #622)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Cancer

• Records: 58 (human studies: 36). Evidence levels: HIGH 2, MODERATE 5, LOW 24, VERY_LOW 6, PRELIMINARY 2, NOT_RATED 19.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 21, INDIRECT 33, VERY_INDIRECT 3, PARTIAL 1. Records rated DIRECT or PARTIAL: 1.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of randomised trials (The lancet. Diabetes & endocrinology, 2021; PMID 34425083; record #13) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Glucagon-like peptide-1 receptor agonists improve biomarkers of inflammation and oxidative stress: A systematic review and meta-analysis of randomised controlled trials (Diabetes, obesity & metabolism, 2021; PMID 33830637; record #470) — MODERATE, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Inflammatory biomarker response to GLP-1 receptor agonists versus other glucose-lowering medications in patients with type 2 diabetes: a systematic review and meta-analysis (Frontiers in endocrinology, 2025; PMID 41625236; record #358) — MODERATE, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear

Strongest contradictory or null evidence:

• Association of Glucagon-Like Peptide-1 Receptor Agonist Use With Risk of Gallbladder and Biliary Diseases: A Systematic Review and Meta-analysis of Randomized Clinical Trials (JAMA internal medicine, 2022; PMID 35344001; record #39) — HIGH, Meta-analysis, direction harm
• Risk of neoplasms with semaglutide in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials (Frontiers in pharmacology, 2026; PMID 42757217; record #631) — MODERATE, Meta-analysis, direction harm
• Meta-analysis of the efficacy of liraglutide in patients with type 2 diabetes accompanied by incipient nephropathy (Experimental and therapeutic medicine, 2019; PMID 31258671; record #479) — MODERATE, Meta-analysis, direction harm

New records since previous synthesis:

• EASL-EASD-EASO Guidance for the Use of Resmetirom and Semaglutide as MASH-Targeted Therapy (Journal of hepatology, 2026; PMID 42805503; record #851)
• The Effect of Glucagon-Like Peptide 1 Receptor Agonists on Peri- and Postmenopausal Breast Cancer Outcomes (Journal of surgical oncology, 2026; PMID 42813380; record #822)
• Hypothalamic obesity in pediatric vs. adult craniopharyngioma: mechanisms, management, and cardiometabolic outcomes (Pituitary, 2026; PMID 42801380; record #864)
• Suitability of the ICH S1B(R1) Weight-of-Evidence Framework to Evaluate Glucagon-Like Protein-1 Receptor Agonist (GLP-1RA) Carcinogenicity Risk (Regulatory toxicology and pharmacology : RTP, 2026; PMID 42800499; record #772)
• Long-Term Association Between GLP-1 Receptor Agonist Use and Incident Pancreatic Cancer: A Propensity Score-Matched Retrospective Cohort Study Using the TriNetX Network (Journal of gastrointestinal cancer, 2026; PMID 42745130; record #633)
• Glucagon-like Peptide-1 Receptor Agonists Are Not Associated with Increased Risk of Acute Pancreatitis or Pancreatic Complications, Including Pancreatic Cancer, in Type 2 Diabetes: A Global Propensity-Matched Cohort Study (Journal of personalized medicine, 2026; PMID 42783509; record #775)
• Clinical outcomes associated with GLP-1 receptor agonist use in metabolic dysfunction-associated steatohepatitis: A multinational cohort study (Medicine, 2026; PMID 42736811; record #628)
• Genetic Assessment of Oesophageal Safety of GLP-1 and GIP Receptor Perturbation: A Drug-Target Mendelian Randomisation Study (Biomedicines, 2026; PMID 42792631; record #774)
• The effects of GLP-1 receptor agonists on metabolic inflammatory markers in patients with type 2 diabetes mellitus: a systematic review and meta-analysis (PeerJ, 2026; PMID 41660088; record #355)
• Divergent effects of semaglutide and CRV431 Co-therapy on liver fibrosis and HCC in MASLD mouse model (PloS one, 2026; PMID 42758714; record #549)

Claims in this domain:

• GLP-1 receptor agonists increase the risk of thyroid cancer in humans. → CONTRADICTORY (weakening). Rodent C-cell tumours underlie the boxed warning. A French case-control analysis found increased thyroid and medullary cancer with 1-3 years' use, but a larger Scandinavian active-comparator cohort found no increase (HR 0.93, upper CI 1.31). Detection bias is a concern in the positive study; follow-up remains short for a slow-growing cancer.
• GLP-1 receptor agonists reduce the incidence of obesity-associated cancers. → PRELIMINARY_SIGNAL (unclear). A large EHR cohort in type 2 diabetes found lower incidence of 10 of 13 obesity-associated cancers versus insulin, with weaker or null results versus metformin. Observational, susceptible to confounding by indication and surveillance differences; no randomized cancer-outcome data.

Unresolved questions:

• What happens with use measured in decades rather than years? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Addiction / reward

• Records: 24 (human studies: 18). Evidence levels: MODERATE 4, LOW 12, VERY_LOW 4, PRELIMINARY 2, NOT_RATED 2.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 6, VERY_INDIRECT 4, PARTIAL 4, INDIRECT 10. Records rated DIRECT or PARTIAL: 4.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review (Disease-a-month : DM, 2026; PMID 42855378; record #974) — MODERATE, Systematic review, applicability UNKNOWN, mediation unknown, industry funded: unclear
• The association between glucose-dependent insulinotropic polypeptide and/or glucagon-like peptide-1 receptor agonist prescriptions and substance-related outcomes in patients with opioid and alcohol use disorders: A real-world data analysis (Addiction (Abingdon, England), 2025; PMID 39415416; record #56) — LOW, Retrospective cohort, applicability PARTIAL, mediation unlikely, industry funded: no
• Glucagon-like peptide-1 receptor agonists and tirzepatide are associated with reduced mortality, cardiovascular, and psychiatric risks in patients with hidradenitis suppurativa and type 2 diabetes and/or obesity: a retrospective cohort study (Frontiers in medicine, 2026; PMID 42741157; record #560) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: unclear

Strongest contradictory or null evidence:

• Incremental effects of SGLT2 inhibitors, GLP-1 receptor agonists, and pioglitazone in type 2 diabetes and MASLD across Asian study settings: a systematic review and meta-analysis (Frontiers in endocrinology, 2026; PMID 42745769; record #627) — MODERATE, Meta-analysis, direction null
• Incretin-Based Therapies Versus Bariatric and Metabolic Surgery for Obesity and Type 2 Diabetes Mellitus: A Head-to-Head Systematic Review of Glycaemic, Cardiovascular, Hepatic, Weight, and Quality-of-Life Outcomes (Cureus, 2026; PMID 42677221; record #169) — MODERATE, Systematic review, direction mixed
• Mapping the effectiveness and risks of GLP-1 receptor agonists (Nature medicine, 2025; PMID 39833406; record #20) — LOW, Retrospective cohort, direction mixed

New records since previous synthesis:

• Therapeutic modulation of the gut-brain axis in alcohol use disorder: A systematic review (Metabolism open, 2026; PMID 42750798; record #553)
• Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review (Disease-a-month : DM, 2026; PMID 42855378; record #974)
• The dual incretin agonist tirzepatide blunts nicotine-induced behaviours and neurochemistry in male mice (British journal of pharmacology, 2026; PMID 42805610; record #879)
• No Heavy Drinking Days and Percentage of Days Abstinent in a Randomized Trial of Adjunctive Ketamine for Alcohol Use Disorder: Secondary Analysis of the KARE Trial (preprint server, 2026; DOI 10.64898/2026.09.26.26363761; record #897)
• Hypothalamic obesity in pediatric vs. adult craniopharyngioma: mechanisms, management, and cardiometabolic outcomes (Pituitary, 2026; PMID 42801380; record #864)
• Central Nervous System Effects of GLP-1 Receptor Agonists: A Systematic Review of Human Neuroimaging Studies (Neuroscience and biobehavioral reviews, 2026; PMID 42762879; record #604)
• Dorsomedial striatal GABA dynamics organize palatable reward consumption and are reshaped by GLP-1 receptor agonism (biorxiv (preprint), 2026; DOI 10.64898/2026.09.03.749293; record #663)
• Divergent effects of semaglutide and CRV431 Co-therapy on liver fibrosis and HCC in MASLD mouse model (PloS one, 2026; PMID 42758714; record #549)
• Glucagon-like peptide-1 receptor agonists and tirzepatide are associated with reduced mortality, cardiovascular, and psychiatric risks in patients with hidradenitis suppurativa and type 2 diabetes and/or obesity: a retrospective cohort study (Frontiers in medicine, 2026; PMID 42741157; record #560)
• Incremental effects of SGLT2 inhibitors, GLP-1 receptor agonists, and pioglitazone in type 2 diabetes and MASLD across Asian study settings: a systematic review and meta-analysis (Frontiers in endocrinology, 2026; PMID 42745769; record #627)

Claims in this domain:

• GLP-1 receptor agonists reduce alcohol and other substance use. → PRELIMINARY_SIGNAL (strengthening). A small phase 2 RCT (n=48, 9 weeks, low doses) reduced laboratory alcohol self-administration, craving and drinks per drinking day. Large observational cohorts show lower opioid overdose and alcohol intoxication rates. No phase 3 trial has reported; the RCT population was young and not selected for weight.

Unresolved questions:

• Is there an effective dose for non-weight indications below weight-loss doses? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Biological aging

• Records: 13 (human studies: 8). Evidence levels: HIGH 1, MODERATE 2, LOW 2, VERY_LOW 2, PRELIMINARY 2, NOT_RATED 4.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 5, UNKNOWN 5, VERY_INDIRECT 3. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: increased (more higher-certainty records).

Strongest supporting evidence (benefit direction, by evidence level):

• Efficacy and Safety of Semaglutide According to Frailty Status: A Post Hoc Analysis of the SELECT Randomized Clinical Trial (JAMA cardiology, 2026; PMID 42747817; record #587) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: unclear
• Diabetes, Adiposity, and Functional Phenotypes in HFpEF: A Systematic Review of Recent Treatment-Response Evidence (Cureus, 2026; PMID 42729808; record #123) — MODERATE, Systematic review, applicability INDIRECT, mediation possibly, industry funded: unclear

Strongest contradictory or null evidence:

• Semaglutide reduces proteomic organ-specific biological age across randomized clinical trials (preprint server, 2026; DOI 10.21203/rs.3.rs-11082091/v1; record #792) — PRELIMINARY, Randomized controlled trial, direction mixed

New records since previous synthesis:

• Association of GLP1-Receptor Agonist Use With Frailty and Falls in Adults With Type 2 Diabetes (Diabetes, obesity & metabolism, 2026; PMID 42844025; record #975)
• Patterns of GLP-1 Receptor Agonist Initiation Compared With Other Glucose-Lowering and Anti-Obesity Therapies Among Older Adults (preprint server, 2026; DOI 10.64898/2026.09.29.26364340; record #990)
• Semaglutide reduces proteomic organ-specific biological age across randomized clinical trials (preprint server, 2026; DOI 10.21203/rs.3.rs-11082091/v1; record #792)
• Efficacy and Safety of Semaglutide According to Frailty Status: A Post Hoc Analysis of the SELECT Randomized Clinical Trial (JAMA cardiology, 2026; PMID 42747817; record #587)

Claims in this domain:

• GLP-1 receptor agonists slow biological aging or extend healthspan in humans. → MECHANISTIC_ONLY (stable). Reviews describe mitochondrial, senescence and vascular-aging mechanisms and cite aged-mouse multi-omic data. No human trial has a prespecified aging endpoint; no epigenetic-clock or healthspan outcome trial exists. Mortality reductions in CVOTs occurred in high-risk diabetic or cardiovascular populations.

Unresolved questions:

• Is chronic GLP-1 receptor agonist use beneficial, neutral or harmful in metabolically healthy people? (open)
• Do GLP-1 receptor agonists affect biological aging in humans? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Mortality

• Records: 74 (human studies: 68). Evidence levels: HIGH 10, MODERATE 16, LOW 35, VERY_LOW 5, PRELIMINARY 7, NOT_RATED 1.
• Applicability to healthy normal-weight adults 55-75: PARTIAL 2, UNKNOWN 16, INDIRECT 52, VERY_INDIRECT 4. Records rated DIRECT or PARTIAL: 2.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Effects of GLP-1 receptor agonists on kidney and cardiovascular disease outcomes: a meta-analysis of randomised controlled trials (The lancet. Diabetes & endocrinology, 2025; PMID 39608381; record #34) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of randomised trials (The lancet. Diabetes & endocrinology, 2021; PMID 34425083; record #13) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (The New England journal of medicine, 2023; PMID 37952131; record #1) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes

Strongest contradictory or null evidence:

• Cardiovascular Outcomes with Tirzepatide versus Dulaglutide in Type 2 Diabetes (The New England journal of medicine, 2025; PMID 41406444; record #59) — HIGH, Randomized controlled trial, direction mixed
• Neuropsychiatric Effects of Glucagon-Like Peptide-1 Receptor Agonists in Schizophrenia-Spectrum Disorders: A Systematic Review (Cureus, 2026; PMID 42725235; record #128) — MODERATE, Systematic review, direction mixed
• Safety and Glycemic Efficacy of Perioperative Liraglutide in Cardiac Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials (Cardiology in review, 2026; PMID 42693519; record #181) — MODERATE, Meta-analysis, direction null

New records since previous synthesis:

• Cardiovascular Risk in SELECT-Eligible MI Patients With Overweight or Obesity: The Western Denmark Heart Registry (JACC. Advances, 2026; PMID 42858539; record #930)
• Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review (Disease-a-month : DM, 2026; PMID 42855378; record #974)
• GLP-1 Receptor Agonists and Dual GIP/GLP-1 and Reduction in Major Cardiovascular Events: A Systematic Review and Network Meta-Analysis (preprint server, 2026; DOI 10.20944/preprints202610.0314.v1; record #991)
• GLP-1 Receptor Agonists and Risk of Kidney Replacement Therapy and Health Care Utilization in Bipolar Disorder With Chronic Kidney Disease (The Journal of clinical psychiatry, 2026; PMID 42848524; record #958)
• Pharmacological treatment strategies to prevent heart failure across the cardiovascular-kidney-metabolic spectrum: an EJHF Expert Consensus Statement (European journal of heart failure, 2026; PMID 42817848; record #836)
• Glucagon-Like Peptide-1 Agonists and the Incidence of Atrial Fibrillation in Obese Patients With Heart Failure With Preserved Ejection Fraction and No Diabetes (Journal of arrhythmia, 2026; PMID 42774613; record #733)
• A Novel Dual Therapy for Diabetic Ischemic Heart Injury: Sinomenine and Liraglutide Restore Mitochondrial Homeostasis and Suppress Pyroptosis (FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 2026; PMID 42762056; record #543)
• The Effect of Glucagon-Like Peptide 1 Receptor Agonists on Peri- and Postmenopausal Breast Cancer Outcomes (Journal of surgical oncology, 2026; PMID 42813380; record #822)
• GHRH and GLP-1 receptor agonism promote human β-cell survival and improve glucose homeostasis in diabetic mice (Endocrinology, 2026; PMID 42811814; record #824)
• Comparative outcomes of GLP-1 receptor agonist and SGLT2 inhibitor users after liver transplantation: An emulated target trial (Metabolism: clinical and experimental, 2026; PMID 42810614; record #848)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Metabolic health

• Records: 200 (human studies: 160). Evidence levels: HIGH 6, MODERATE 51, LOW 86, VERY_LOW 24, PRELIMINARY 10, NOT_RATED 23.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 129, UNKNOWN 54, VERY_INDIRECT 16, PARTIAL 1. Records rated DIRECT or PARTIAL: 1.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Oral Semaglutide and Change in Cardiovascular Risk Factors in High-Risk Type 2 Diabetes: A Post Hoc Secondary Analysis of the SOUL Randomized Clinical Trial (JAMA cardiology, 2026; PMID 41879791; record #349) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: unclear
• Once-Weekly Semaglutide in Adults with Overweight or Obesity (The New England journal of medicine, 2021; PMID 33567185; record #42) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation not_applicable, industry funded: yes
• Semaglutide and NYHA Functional Class in Obesity-Related Heart Failure With Preserved Ejection Fraction: The STEP-HFpEF Program (Journal of the American College of Cardiology, 2024; PMID 38913004; record #419) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: unclear

Strongest contradictory or null evidence:

• Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial (Lancet (London, England), 2026; PMID 42815506; record #839) — HIGH, Randomized controlled trial, direction harm
• Risk of neoplasms with semaglutide in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials (Frontiers in pharmacology, 2026; PMID 42757217; record #631) — MODERATE, Meta-analysis, direction harm
• Long-Term Cardiovascular Outcomes of Glucagon-Like Peptide-1 Receptor Agonists in Non-diabetic Obesity: A Systematic Review and Meta-Analysis (Cureus, 2026; PMID 41658748; record #356) — MODERATE, Meta-analysis, direction mixed

New records since previous synthesis:

• Incretin-based injectable strategies versus intensified insulin for treatment intensification and simplification in type 2 diabetes: a systematic review and meta-analysis (Journal of diabetes and metabolic disorders, 2026; PMID 42802751; record #895)
• Evaluation of clinical relevance of weight nadirs and weight regain during 3 years of treatment with tirzepatide in participants with obesity or overweight and prediabetes (Obesity pillars, 2026; PMID 42831032; record #984)
• Global Landscape and Thematic Evolution of Selective GLP-1 Receptor Agonists and GLP-1-Based Multi-Receptor Agonists in Type 2 Diabetes Mellitus: A Bibliometric Analysis (Endocrinology, diabetes & metabolism, 2026; PMID 42817068; record #837)
• Current review of glucagon-like peptide 1 receptor agonists and risk of nonarteritic anterior ischemic optic neuropathy (Journal of the Endocrine Society, 2026; PMID 42857401; record #955)
• Preconception incretin therapy reduces pregnancy and cardiometabolic outcomes in polycystic ovary syndrome (The Journal of clinical endocrinology and metabolism, 2026; PMID 42857939; record #931)
• Short-term clinical efficacy and recorded adverse events of semaglutide combined with dapagliflozin in patients with type 2 diabetes mellitus and chronic kidney disease (Medicine, 2026; PMID 42854065; record #911)
• Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review (Disease-a-month : DM, 2026; PMID 42855378; record #974)
• Tirzepatide alleviates hepatic steatosis and inflammation in MASLD partly through suppression of macrophage Dectin-1/Syk/NF-κB signaling (European journal of pharmacology, 2026; PMID 42849688; record #915)
• Disparities in GLP-1RA and SGLT2i Uptake: a Systematic Review and an Equity-First Framework for Cardiovascular-Kidney-Metabolic Care (Current cardiology reports, 2026; PMID 42842171; record #944)
• An RNA thermogenic therapy to preserve lean mass and enhance metabolic health during GLP-1 weight loss (Proceedings of the National Academy of Sciences of the United States of America, 2026; PMID 42789307; record #759)

Unresolved questions:

• Is chronic GLP-1 receptor agonist use beneficial, neutral or harmful in metabolically healthy people? (open)
• Is there an effective dose for non-weight indications below weight-loss doses? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Adverse effects / safety

• Records: 157 (human studies: 141). Evidence levels: HIGH 9, MODERATE 52, LOW 47, VERY_LOW 26, PRELIMINARY 11, NOT_RATED 12.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 46, INDIRECT 106, VERY_INDIRECT 4, PARTIAL 1. Records rated DIRECT or PARTIAL: 1.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Effects of GLP-1 receptor agonists on kidney and cardiovascular disease outcomes: a meta-analysis of randomised controlled trials (The lancet. Diabetes & endocrinology, 2025; PMID 39608381; record #34) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of randomised trials (The lancet. Diabetes & endocrinology, 2021; PMID 34425083; record #13) — HIGH, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (The New England journal of medicine, 2023; PMID 37952131; record #1) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes

Strongest contradictory or null evidence:

• Association of Glucagon-Like Peptide-1 Receptor Agonist Use With Risk of Gallbladder and Biliary Diseases: A Systematic Review and Meta-analysis of Randomized Clinical Trials (JAMA internal medicine, 2022; PMID 35344001; record #39) — HIGH, Meta-analysis, direction harm
• Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial (Lancet (London, England), 2026; PMID 42815506; record #839) — HIGH, Randomized controlled trial, direction harm
• Long-Term Cardiovascular Outcomes of Glucagon-Like Peptide-1 Receptor Agonists in Non-diabetic Obesity: A Systematic Review and Meta-Analysis (Cureus, 2026; PMID 41658748; record #356) — MODERATE, Meta-analysis, direction mixed

New records since previous synthesis:

• EASL-EASD-EASO Guidance for the Use of Resmetirom and Semaglutide as MASH-Targeted Therapy (Journal of hepatology, 2026; PMID 42805503; record #851)
• Incretin-based injectable strategies versus intensified insulin for treatment intensification and simplification in type 2 diabetes: a systematic review and meta-analysis (Journal of diabetes and metabolic disorders, 2026; PMID 42802751; record #895)
• Integrating incretin-based therapies into comprehensive obesity care: an EASO position statement (The Lancet regional health. Europe, 2026; PMID 42733510; record #650)
• Tirzepatide Initiation in Lithium-Treated Bipolar Disorder: Renal Biomarker Trajectories and Lithium Safety Signals Over 12 Months in a Real-World Cohort (Human psychopharmacology, 2026; PMID 42803597; record #860)
• Current review of glucagon-like peptide 1 receptor agonists and risk of nonarteritic anterior ischemic optic neuropathy (Journal of the Endocrine Society, 2026; PMID 42857401; record #955)
• Preconception incretin therapy reduces pregnancy and cardiometabolic outcomes in polycystic ovary syndrome (The Journal of clinical endocrinology and metabolism, 2026; PMID 42857939; record #931)
• Short-term clinical efficacy and recorded adverse events of semaglutide combined with dapagliflozin in patients with type 2 diabetes mellitus and chronic kidney disease (Medicine, 2026; PMID 42854065; record #911)
• Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review (Disease-a-month : DM, 2026; PMID 42855378; record #974)
• Adverse Oral and Salivary Effects Associated With Glucagon-Like Peptide-1 Receptor Agonists: Clinical Insights (Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology, 2026; PMID 42843413; record #970)
• GLP-1R expression and dermatological diseases: a mendelian randomization and real-world study (Endocrine, 2026; PMID 42842067; record #971)

Unresolved questions:

• What is the risk-benefit balance in normal-weight adults aged 55-75? (open)
• What happens with use measured in decades rather than years? (open)
• How large are rare irreversible harms (NAION, pancreatitis, obstruction) and are they dose-related? (open)
• Does adding glucagon-receptor agonism (retatrutide, survodutide, mazdutide) change the benefit or harm profile relative to GLP-1 agonism alone, and would any of that carry over to normal-weight adults? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Gastrointestinal

• Records: 94 (human studies: 71). Evidence levels: HIGH 5, MODERATE 31, LOW 21, VERY_LOW 12, PRELIMINARY 4, NOT_RATED 21.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 56, UNKNOWN 35, VERY_INDIRECT 2, PARTIAL 1. Records rated DIRECT or PARTIAL: 1.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (The New England journal of medicine, 2023; PMID 37952131; record #1) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes
• Dulaglutide and cardiovascular outcomes in type 2 diabetes (REWIND): a double-blind, randomised placebo-controlled trial (Lancet (London, England), 2019; PMID 31189511; record #12) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: yes
• Once-Weekly Semaglutide in Adults with Overweight or Obesity (The New England journal of medicine, 2021; PMID 33567185; record #42) — HIGH, Randomized controlled trial, applicability INDIRECT, mediation not_applicable, industry funded: yes

Strongest contradictory or null evidence:

• Association of Glucagon-Like Peptide-1 Receptor Agonist Use With Risk of Gallbladder and Biliary Diseases: A Systematic Review and Meta-analysis of Randomized Clinical Trials (JAMA internal medicine, 2022; PMID 35344001; record #39) — HIGH, Meta-analysis, direction harm
• Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial (Lancet (London, England), 2026; PMID 42815506; record #839) — HIGH, Randomized controlled trial, direction harm
• Weight regain following discontinuation of glucagon-like peptide-1 receptor agonists in adults who are overweight or obese: a systematic review and meta-analysis (PeerJ, 2026; PMID 42729958; record #121) — MODERATE, Meta-analysis, direction harm

New records since previous synthesis:

• Incretin-based injectable strategies versus intensified insulin for treatment intensification and simplification in type 2 diabetes: a systematic review and meta-analysis (Journal of diabetes and metabolic disorders, 2026; PMID 42802751; record #895)
• Tirzepatide Initiation in Lithium-Treated Bipolar Disorder: Renal Biomarker Trajectories and Lithium Safety Signals Over 12 Months in a Real-World Cohort (Human psychopharmacology, 2026; PMID 42803597; record #860)
• Adverse Oral and Salivary Effects Associated With Glucagon-Like Peptide-1 Receptor Agonists: Clinical Insights (Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology, 2026; PMID 42843413; record #970)
• Oral small-molecule GLP-1RA safiglipron versus dapagliflozin in type 2 diabetes: a randomized, double-blind, active-comparator-controlled phase 3 trial (Nature medicine, 2026; PMID 42834229; record #983)
• Nisotirostide (LY3457263), a novel NPY2 receptor agonist for type 2 diabetes and obesity: From discovery to clinical proof of concept (Molecular metabolism, 2026; PMID 42829171; record #865)
• Survodutide Once Weekly in Adults with Obesity and Type 2 Diabetes (The New England journal of medicine, 2026; PMID 42820639; record #887)
• Gastrointestinal adverse effects of GLP-1 receptor agonists and dual GIP/GLP-1 receptor agonists: A narrative expert review of approved therapies, oral formulations, and pipeline agents (Nutrition in clinical practice : official publication of the American Society for Parenteral and Enteral Nutrition, 2026; PMID 42808923; record #891)
• Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial (Lancet (London, England), 2026; PMID 42815506; record #839)
• Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial (Lancet (London, England), 2026; PMID 42810372; record #795)
• Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity (The New England journal of medicine, 2026; PMID 42814954; record #868)

Claims in this domain:

• GLP-1 receptor agonists cause serious gastrointestinal and biliary adverse events. → ESTABLISHED (stable). Gallbladder/biliary disease is increased in a meta-analysis of 76 RCTs (RR 1.37; higher with weight-loss doses, RR 2.29). Cohort data show increased pancreatitis, gastroparesis and bowel obstruction versus bupropion-naltrexone. The VA atlas adds drug-induced pancreatitis, nephrolithiasis and interstitial nephritis signals. GI intolerance drives discontinuation (16.6% vs 8.2% in SELECT).

Unresolved questions:

• How large are rare irreversible harms (NAION, pancreatitis, obstruction) and are they dose-related? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Psychiatric

• Records: 29 (human studies: 27). Evidence levels: MODERATE 4, LOW 18, VERY_LOW 3, PRELIMINARY 2, NOT_RATED 2.
• Applicability to healthy normal-weight adults 55-75: UNKNOWN 9, INDIRECT 18, PARTIAL 2. Records rated DIRECT or PARTIAL: 2.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Adjunctive GLP-1 receptor agonists for cardiometabolic risk in antipsychotic-treated patients: A GRADE-assessed meta-analysis of randomized trials (Journal of psychopharmacology (Oxford, England), 2026; PMID 42746999; record #642) — MODERATE, Meta-analysis, applicability UNKNOWN, mediation unknown, industry funded: unclear
• Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review (Disease-a-month : DM, 2026; PMID 42855378; record #974) — MODERATE, Systematic review, applicability UNKNOWN, mediation unknown, industry funded: unclear
• The association between glucose-dependent insulinotropic polypeptide and/or glucagon-like peptide-1 receptor agonist prescriptions and substance-related outcomes in patients with opioid and alcohol use disorders: A real-world data analysis (Addiction (Abingdon, England), 2025; PMID 39415416; record #56) — LOW, Retrospective cohort, applicability PARTIAL, mediation unlikely, industry funded: no

Strongest contradictory or null evidence:

• Neuropsychiatric Effects of Glucagon-Like Peptide-1 Receptor Agonists in Schizophrenia-Spectrum Disorders: A Systematic Review (Cureus, 2026; PMID 42725235; record #128) — MODERATE, Systematic review, direction mixed
• Neuropsychiatric Outcomes Associated with GLP-1 Receptor Agonists in Adults with Overweight or Obesity: A Systematic Review (Brain sciences, 2026; PMID 42793351; record #783) — MODERATE, Systematic review, direction null
• GLP-1 Receptor Agonist Use and Risk of Suicide Death (JAMA internal medicine, 2024; PMID 39226030; record #17) — LOW, Retrospective cohort, direction null

New records since previous synthesis:

• Therapeutic modulation of the gut-brain axis in alcohol use disorder: A systematic review (Metabolism open, 2026; PMID 42750798; record #553)
• Tirzepatide Initiation in Lithium-Treated Bipolar Disorder: Renal Biomarker Trajectories and Lithium Safety Signals Over 12 Months in a Real-World Cohort (Human psychopharmacology, 2026; PMID 42803597; record #860)
• Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review (Disease-a-month : DM, 2026; PMID 42855378; record #974)
• GLP-1 Receptor Agonists and Risk of Kidney Replacement Therapy and Health Care Utilization in Bipolar Disorder With Chronic Kidney Disease (The Journal of clinical psychiatry, 2026; PMID 42848524; record #958)
• Glucagon-like peptide-1 receptor agonists in hidradenitis suppurativa: A nationwide cohort study (Journal of the European Academy of Dermatology and Venereology : JEADV, 2026; PMID 42828450; record #805)
• Weight Reduction Heterogenicity and Mediators of GLP-1RAs and Dual Agonists for Individuals With Obesity: A Meta-Analysis (Clinical obesity, 2026; PMID 42733128; record #630)
• Increasing Direct-to-Consumer Use of Semax and Selank Peptides Decoded from LLM-Curated Clinical Notes and Physician Adjudication (preprint server, 2026; DOI 10.20944/preprints202609.2396.v1; record #899)
• Central Nervous System Effects of GLP-1 Receptor Agonists: A Systematic Review of Human Neuroimaging Studies (Neuroscience and biobehavioral reviews, 2026; PMID 42762879; record #604)
• Semaglutide as adjunct treatment for obesity in adolescents receiving antipsychotic medication (the GOAL trial): protocol for a single-arm, open-label feasibility study (BMJ open, 2026; PMID 42754274; record #611)
• Adjunctive GLP-1 receptor agonists for cardiometabolic risk in antipsychotic-treated patients: A GRADE-assessed meta-analysis of randomized trials (Journal of psychopharmacology (Oxford, England), 2026; PMID 42746999; record #642)

Claims in this domain:

• GLP-1 receptor agonists increase suicidal ideation or suicide. → NOT_SUPPORTED (weakening). Pharmacovigilance reports prompted regulatory review. Two large cohorts (US EHR; Swedish/Danish registers with SGLT2i active comparator) found no increase in suicidal ideation or suicide death; the Nordic upper confidence limit excludes more than 0.16 extra deaths per 1,000 person-years.

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Ophthalmologic

• Records: 24 (human studies: 12). Evidence levels: MODERATE 1, LOW 5, VERY_LOW 4, PRELIMINARY 2, NOT_RATED 12.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 9, UNKNOWN 15. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: unchanged.

Strongest supporting evidence (benefit direction, by evidence level):

• Effectiveness of Adding GLP-1 Receptor Agonists to SGLT2 Inhibitor Therapy in Chronic Kidney Disease: A Population Based Study (Diabetes, obesity & metabolism, 2026; PMID 42802242; record #854) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: no

Strongest contradictory or null evidence:

• Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes (The New England journal of medicine, 2016; PMID 27633186; record #11) — MODERATE, Randomized controlled trial, direction mixed
• GLP1-RA Use and Risk of Non-arteritic Anterior Ischemic Optic Neuropathy in Patients with Type 2 Diabetes (Ophthalmology. Retina, 2026; PMID 42692107; record #236) — LOW, Retrospective cohort, direction harm
• Prehospital glucagon-like peptide-1 receptor agonists are not associated with reduced inpatient opioid exposure but with shorter hospital length of stay after total joint arthroplasty (Frontiers in endocrinology, 2026; PMID 42698481; record #94) — LOW, Retrospective cohort, direction mixed

New records since previous synthesis:

• Current review of glucagon-like peptide 1 receptor agonists and risk of nonarteritic anterior ischemic optic neuropathy (Journal of the Endocrine Society, 2026; PMID 42857401; record #955)
• Non-Arteritic Anterior Ischaemic Optic Neuropathy Associated with Semaglutide use (Irish medical journal, 2026; PMID 42808150; record #881)
• Effectiveness of Adding GLP-1 Receptor Agonists to SGLT2 Inhibitor Therapy in Chronic Kidney Disease: A Population Based Study (Diabetes, obesity & metabolism, 2026; PMID 42802242; record #854)
• Comparative Risk of Nonarteritic Anterior Ischemic Optic Neuropathy Among Glucagon-Like Peptide-1 Receptor Agonists: An Integrated Safety and Mechanistic Analysis (Diabetes, obesity & metabolism, 2026; PMID 42768849; record #740)
• Semaglutide and Nonarteritic Anterior Ischemic Optic Neuropathy: Notoriety Bias or True Ocular Toxicity? (medrxiv (preprint), 2026; DOI 10.64898/2026.09.06.26362369; record #660)
• GLP-1-based treatments and long-term clinical outcomes in MASLD amongst older adults: a retrospective cohort study (Age and ageing, 2026; PMID 42765724; record #746)

Claims in this domain:

• Semaglutide increases the risk of non-arteritic anterior ischaemic optic neuropathy (NAION). → EVIDENCE_OF_HARM (strengthening). A single-centre neuro-ophthalmology cohort first reported HR 4.28 (T2D) and higher in obesity; a 2026 meta-analysis of observational studies found HR ~2.2 with very low absolute risk (~1 extra case per 7,000 treated per year). The meta-analysis authors note consistency with regulatory communications. Observational evidence; causality not proven; rare but irreversible.

Unresolved questions:

• How large are rare irreversible harms (NAION, pancreatitis, obstruction) and are they dose-related? (open)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Sleep

• Records: 21 (human studies: 19). Evidence levels: MODERATE 6, LOW 9, VERY_LOW 2, PRELIMINARY 3, NOT_RATED 1.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 17, UNKNOWN 4. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: increased (more higher-certainty records).

Strongest supporting evidence (benefit direction, by evidence level):

• Tirzepatide Beyond Diabetes and Obesity: Systematic Review and Meta-Analysis of Multisystem Therapeutic Benefits (Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists, 2026; PMID 42061648; record #341) — MODERATE, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Efficacy of SGLT2 inhibitors, GLP-1 receptor agonists, and aerobic exercise for moderate-to-severe obstructive sleep apnea in overweight or obese patients: a network meta-analysis (Frontiers in endocrinology, 2026; PMID 42676363; record #170) — MODERATE, Meta-analysis, applicability INDIRECT, mediation possibly, industry funded: unclear
• Higher semaglutide dose is associated with lower neuropsychiatric event incidence independent of weight loss (npj metabolic health and disease, 2026; PMID 42680805; record #195) — LOW, Retrospective cohort, applicability INDIRECT, mediation specifically_tested, industry funded: unclear

Strongest contradictory or null evidence:

• Safety and efficacy of glucagon-like peptide-1 receptor agonists in patients with obstructive sleep apnea: a systematic review and meta-analysis of randomized controlled trials (European clinical respiratory journal, 2025; PMID 40144943; record #401) — MODERATE, Meta-analysis, direction mixed
• Effectiveness of GLP-1 receptor agonists to prevent obstructive sleep apnea in patients with type 2 diabetes: active comparator, new user cohort study (American journal of respiratory and critical care medicine, 2026; PMID 42745463; record #592) — LOW, Retrospective cohort, direction null
• Psychiatric Safety of GLP-1 and Dual GIP/GLP-1 Receptor Agonists in Adolescents With Obesity (Diabetes, obesity & metabolism, 2026; PMID 42736027; record #648) — LOW, Retrospective cohort, direction mixed

New records since previous synthesis:

• Current review of glucagon-like peptide 1 receptor agonists and risk of nonarteritic anterior ischemic optic neuropathy (Journal of the Endocrine Society, 2026; PMID 42857401; record #955)
• GLP-1 receptor agonists for obstructive sleep apnea: a meta-analysis of randomized controlled trials (Sleep & breathing = Schlaf & Atmung, 2026; PMID 42837024; record #982)
• Oral semaglutide for weight loss and liver fibrosis in overweight and obesity: A randomized controlled trial (Indian journal of gastroenterology : official journal of the Indian Society of Gastroenterology, 2026; PMID 41066034; record #375)
• Weight Reduction Heterogenicity and Mediators of GLP-1RAs and Dual Agonists for Individuals With Obesity: A Meta-Analysis (Clinical obesity, 2026; PMID 42733128; record #630)
• Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity (The New England journal of medicine, 2026; PMID 42814954; record #868)
• Increasing Direct-to-Consumer Use of Semax and Selank Peptides Decoded from LLM-Curated Clinical Notes and Physician Adjudication (preprint server, 2026; DOI 10.20944/preprints202609.2396.v1; record #899)
• Effectiveness of GLP-1 receptor agonists to prevent obstructive sleep apnea in patients with type 2 diabetes: active comparator, new user cohort study (American journal of respiratory and critical care medicine, 2026; PMID 42745463; record #592)
• Obstructive sleep apnea, GLP-1 receptor agonist pharmacotherapy, and the oral microbiome: competing biological influences and implications for oral health monitoring (Clinical oral investigations, 2026; PMID 42734711; record #622)
• Psychiatric Safety of GLP-1 and Dual GIP/GLP-1 Receptor Agonists in Adolescents With Obesity (Diabetes, obesity & metabolism, 2026; PMID 42736027; record #648)
• Investigating the Association Between Semaglutide Use and Mood Disorders in Polyendocrine Metabolic Ovarian Syndrome: A Retrospective Cohort Study​ (Cureus, 2026; PMID 42741750; record #644)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Other emerging indication

• Records: 20 (human studies: 19). Evidence levels: MODERATE 1, LOW 16, VERY_LOW 2, PRELIMINARY 1.
• Applicability to healthy normal-weight adults 55-75: INDIRECT 13, UNKNOWN 6, VERY_INDIRECT 1. Records rated DIRECT or PARTIAL: 0.
• Confidence change since last synthesis: decreased or complicated (new null/harm randomized or synthesis evidence).

Strongest supporting evidence (benefit direction, by evidence level):

• Tirzepatide and the risk of asthma exacerbations in patients with type 2 diabetes (Frontiers in endocrinology, 2026; PMID 42712413; record #81) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: unclear
• Glucagon-like peptide-1 receptor agonists and tirzepatide are associated with reduced mortality, cardiovascular, and psychiatric risks in patients with hidradenitis suppurativa and type 2 diabetes and/or obesity: a retrospective cohort study (Frontiers in medicine, 2026; PMID 42741157; record #560) — LOW, Retrospective cohort, applicability INDIRECT, mediation possibly, industry funded: unclear
• Effects of combined metformin and semaglutide therapy on body weight, metabolic parameters, and reproductive outcomes in overweight/obese women with polycystic ovary syndrome: a prospective, randomized, controlled, open-label clinical trial (Reproductive biology and endocrinology : RB&E, 2025; PMID 40713699; record #385) — LOW, Randomized controlled trial, applicability INDIRECT, mediation possibly, industry funded: unclear

Strongest contradictory or null evidence:

• Comparative Efficacy and Safety of Liraglutide Versus Metformin in Women With Polyendocrine Metabolic Ovarian Syndrome (PMOS): A Systematic Review and Meta-Analysis of Randomized Controlled Trials (Cureus, 2026; PMID 42830876; record #989) — MODERATE, Meta-analysis, direction mixed
• Impact of antidiabetic agents on COPD exacerbations in patients with type 2 diabetes mellitus: A systematic review and network meta-analysis (Diabetes & vascular disease research, 2026; PMID 42821775; record #896) — LOW, Meta-analysis, direction mixed
• Preconception incretin therapy reduces pregnancy and cardiometabolic outcomes in polycystic ovary syndrome (The Journal of clinical endocrinology and metabolism, 2026; PMID 42857939; record #931) — LOW, Retrospective cohort, direction mixed

New records since previous synthesis:

• Preconception incretin therapy reduces pregnancy and cardiometabolic outcomes in polycystic ovary syndrome (The Journal of clinical endocrinology and metabolism, 2026; PMID 42857939; record #931)
• Glucagon-like peptide-1 receptor agonists in hidradenitis suppurativa: A nationwide cohort study (Journal of the European Academy of Dermatology and Venereology : JEADV, 2026; PMID 42828450; record #805)
• GLP-1 Receptor Agonists in Dermatology: Prescribing Frameworks, Access, and the Emerging Pipeline (Clinics in dermatology, 2026; PMID 42777891; record #766)
• Effects of semaglutide on subclinical cardiovascular health in people with HIV (AIDS (London, England), 2026; PMID 42752515; record #581)
• Comparative Efficacy and Safety of Liraglutide Versus Metformin in Women With Polyendocrine Metabolic Ovarian Syndrome (PMOS): A Systematic Review and Meta-Analysis of Randomized Controlled Trials (Cureus, 2026; PMID 42830876; record #989)
• Short-Term Combined Treatment With Tirzepatide and Metformin for Overweight/Obese Chinese Women With Polycystic Ovary Syndrome: A Prospective, Open-Label, Randomised Controlled Trial (Diabetes, obesity & metabolism, 2026; PMID 42236268; record #334)
• Effects of Semaglutide on Cognitive Function in People With HIV: A Randomized, Controlled Trial (Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2026; PMID 41098140; record #373)
• Glucagon-like peptide-1 receptor agonists and tirzepatide are associated with reduced mortality, cardiovascular, and psychiatric risks in patients with hidradenitis suppurativa and type 2 diabetes and/or obesity: a retrospective cohort study (Frontiers in medicine, 2026; PMID 42741157; record #560)
• Semaglutide and pioglitazone restore airway mucosal homeostasis by resolving Pseudomonas aeruginosa pyocyanin-induced mucus hypersecretion, ciliostasis, and type 2 airway inflammation (Frontiers in immunology, 2026; PMID 42769032; record #709)
• Prior Use of GLP-1 Receptor Agonists versus SGLT2 Inhibitors and Clinical Outcomes After Sepsis in Patients with Type 2 Diabetes: A Propensity Score-Matched Cohort Study (Drug design, development and therapy, 2026; PMID 42829714; record #832)

Applicability note: records rated DIRECT for the target population: 0. No direct evidence exists in this domain for healthy normal-weight older adults.

Evidence shifts since previous synthesis

• [notable] trial_completed: Trial completed: Semaglutide in Women With Polycystic Ovary Syndrome and Obesity
• [minor] trial_status_change: Trial status changed to recruiting: Weight-loss Drug for Fertility-Sparing Treatment of Atypical Hyperplasia and Low-grade Cancer of the Endometrium
• [major] non_obese_human_evidence: Human evidence including non-obese or healthy participants: Cardiovascular Risk in SELECT-Eligible MI Patients With Overweight or Obesity: The Western Denmark Heart Registry
• [notable] new_synthesis: New systematic review / meta-analysis: SGLT2 inhibitors, semaglutide, and finerenone in diabetic kidney disease: a Bayesian network meta-analysis
• [notable] new_synthesis: New systematic review / meta-analysis: Disparities in GLP-1RA and SGLT2i Uptake: a Systematic Review and an Equity-First Framework for Cardiovascular-Kidney-Metabolic Care
• [notable] new_safety_signal: Possible safety signal (Adverse effects / safety, Ophthalmologic): Current review of glucagon-like peptide 1 receptor agonists and risk of nonarteritic anterior ischemic optic neuropathy
• [notable] new_safety_signal: Possible safety signal (Adverse effects / safety, Gastrointestinal): Adverse Oral and Salivary Effects Associated With Glucagon-Like Peptide-1 Receptor Agonists: Clinical Insights
• [notable] mediation_tested: Weight-loss independence addressed: GLP-1R expression and dermatological diseases: a mendelian randomization and real-world study
• [notable] new_synthesis: New systematic review / meta-analysis: Status Of GLP-1 drugs and their application in treating substance use disorders: A systematic review
• [notable] new_synthesis: New systematic review / meta-analysis: GLP-1 receptor agonists for obstructive sleep apnea: a meta-analysis of randomized controlled trials
• [notable] new_safety_signal: Possible safety signal (Adverse effects / safety, Nutrition, Anesthesia / perioperative): Effects of GLP-1 receptor agonists on aesthetic surgery practice: A contemporary review
• [notable] new_synthesis: New systematic review / meta-analysis: Comparative Efficacy and Safety of Liraglutide Versus Metformin in Women With Polyendocrine Metabolic Ovarian Syndrome (PMOS): A Systematic Review and Meta-Analysis of Randomized Controlled Trials
• [notable] new_synthesis: New systematic review / meta-analysis: GLP-1 Receptor Agonists and Dual GIP/GLP-1 and Reduction in Major Cardiovascular Events: A Systematic Review and Network Meta-Analysis
• [minor] trial_status_change: Trial status changed to active_not_recruiting: A Study of Orforglipron (LY3502970) in Participants With Obesity or Overweight and Osteoarthritis (OA) of the Knee
• [minor] trial_status_change: Trial status changed to active_not_recruiting: DUTCH Weight Control in Atrial Fibrillation Study
• [major] new_safety_signal: Possible safety signal (Adverse effects / safety, Gastrointestinal): Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial
• [notable] larger_replication: Substantially larger randomized trial in 'Osteoarthritis': Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity
• [notable] larger_replication: Substantially larger randomized trial in 'Sleep': Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity
• [notable] new_synthesis: New systematic review / meta-analysis: Impact of Glucagon-Like Peptide-1 Receptor Agonists on Mental Health: A Systematic Review of Psychiatric Safety and Antidepressant Potential
• [major] new_safety_signal: Possible safety signal (Adverse effects / safety, Gastrointestinal): Oral small-molecule GLP-1 receptor agonist safiglipron in early type 2 diabetes: a randomized, double-blind, placebo-controlled trial
• [notable] mediation_tested: Weight-loss independence addressed: Gastrointestinal adverse effects of GLP-1 receptor agonists and dual GIP/GLP-1 receptor agonists: A narrative expert review of approved therapies, oral formulations, and pipeline agents
• [notable] new_safety_signal: Possible safety signal (Adverse effects / safety, Gastrointestinal, Anesthesia / perioperative): Gastrointestinal adverse effects of GLP-1 receptor agonists and dual GIP/GLP-1 receptor agonists: A narrative expert review of approved therapies, oral formulations, and pipeline agents
• [notable] new_synthesis: New systematic review / meta-analysis: Incretin-based injectable strategies versus intensified insulin for treatment intensification and simplification in type 2 diabetes: a systematic review and meta-analysis
• [notable] new_synthesis: New systematic review / meta-analysis: Impact of antidiabetic agents on COPD exacerbations in patients with type 2 diabetes mellitus: A systematic review and network meta-analysis
• [notable] new_synthesis: New systematic review / meta-analysis: Incretin-Based Dual and Triple Agonists in Overweight or Obese Individuals: A Systematic Review and Meta-Analysis
• [notable] new_synthesis: New systematic review / meta-analysis: Efficacy and Safety of Dual GLP-1/Glucagon Receptor Agonism in Overweight and Obesity: A Class-Specific Systematic Review and Meta-Analysis
• [notable] new_synthesis: New systematic review / meta-analysis: Effect of Retatrutide, a Novel Triple Receptor Agonist, on Blood Pressure and Lipid Levels: A Systematic Review and Meta-analysis of Randomized Controlled Trials
• [notable] new_synthesis: New systematic review / meta-analysis: Comparative Efficacy and Safety of Glucagon Receptor Agonists on Metabolic Outcomes: A Network Meta-Analysis of Randomised Controlled Trials
• [notable] mediation_tested: Weight-loss independence addressed: Retatrutide And Lipid And Metabolite Profiles In Participants With Obesity With Or Without Type 2 Diabetes
• [notable] larger_replication: Substantially larger randomized trial in 'Sleep': Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial