Effects of Semaglutide on Body Composition and GFR: A Prespecified Analysis of the SMART Trial
- Design
- Randomized trial · 101 participants · Intermediate outcome
- Match to healthy normal-weight adults aged 55–75
- Different populationNon-diabetic CKD with overweight/obesity; small. Relevant to the lean-mass question because roughly a quarter of weight lost was lean tissue.
- Could weight loss explain it?
- Not applicable[Auto] Participants had obesity and/or type 2 diabetes and the abstract does not separate direct drug effects from weight loss or glycaemic improvement.
- Study tier
- Study tier 3Small prespecified analysis of an RCT with imprecise body-composition estimates.
- Assessment
- Version 2 · curated · Sep 13, 2026
Study facts come from the paper. Population match, weight-loss explanation and study tier are our judgments, made against the reference group of healthy normal-weight adults aged 55–75.
In 101 people with kidney disease and overweight or obesity (no diabetes), 24 weeks of semaglutide reduced weight by 9 kg, of which about 2.5 kg was lean mass (imprecise estimate). Body-composition change did not distort kidney-function estimates.
What the study reported
- Drugs
- Semaglutide
- Dose
- 2.4 mg weekly
- Route
- subcutaneous
- Treatment duration
- 24 weeks
- Comparator
- placebo
- Primary outcome
- Prespecified: body composition (bioimpedance), measured and estimated GFR, blood pressure
- Effect
- Weight -9.1 kg; lean body mass -2.5 kg (95% CI -6.6 to 1.6); fat mass -3.9 kg; extracellular water -0.9 L; systolic BP -6.3 mmHg; no correlation between body-composition change and GFR change
- 95% confidence interval
- Not extracted
- Follow-up
- 24 weeks
- Adverse events
- Not extracted
- Limitations
- Auto-classified from abstract only; effect estimates, adverse events and limitations not extracted. Requires manual review.
Who was studied
- Obesity status
- overweight or obesity required
- Diabetes status
- excluded
- Ckd status
- CKD required
- Sample size
- 101
Study quality details
- Study design
- Randomized controlled trial
- Sample size
- 101
- Randomization
- yes
- Blinding
- double-blind
- Comparator
- placebo
- Follow up duration
- 24 weeks
- Outcome type
- bioimpedance body composition
- Replication
- not assessed (auto)
- Consistency with other evidence
- not assessed (auto)
- Population applicability
- INDIRECT
- Statistical precision
- n=101; lean-mass CI includes zero
- Risk of bias
- not assessed (auto)
- Funding conflicts
- yes
- Peer review status
- yes
Funding and conflicts
- Funding
- Novo Nordisk (investigator-initiated, per PubMed grant field)
- Industry funded
- Yes
- Manufacturer
- Novo Nordisk
- Sponsor role
- Funder; investigator-initiated (verify).
- Author conflicts
- Disclosure forms available with the article.
- Independent replication
- unknown
- Notes
- Authors declare relationships with the drug's manufacturer: Novo Nordisk
Funding is shown on every study and never used to score it.
Claims this study bears on
- GLP-1 receptor agonist therapy provides a net clinical benefit to healthy normal-weight adults aged 55-75.Contradicts
Lean mass fell alongside fat mass with semaglutide even in a modest-weight CKD population.
- GLP-1 receptor agonists protect kidney function in people without diabetes.Mixed
SMART: semaglutide reduced lean and fat mass; GFR estimates unaffected by body-composition change (n=101, 24 weeks).
- GLP-1-induced weight loss causes clinically meaningful loss of muscle mass or function.Supports
Semaglutide reduced lean body mass (-2.5 kg vs placebo, not statistically significant) alongside fat mass in CKD with overweight/obesity.
The source, as retrieved
Abstract
[KEY POINTS] Treatment with semaglutide compared with placebo for 24 weeks reduced lean body mass and fat mass in adults with CKD and overweight or obesity. Changes in lean body mass or fat mass during semaglutide treatment did not correlate with changes in creatinine or cystatin C‑eGFR or measured GFR. Semaglutide significantly reduced extracellular water and BP, and changes in BP correlated with extracellular water. [BACKGROUND] The glucagon-like peptide-1 receptor agonist semaglutide reduces hemoglobin A1c, body weight, BP, and GFR decline. Semaglutide may influence serum creatinine and cystatin C levels by nonkidney-related mechanisms and thereby affect eGFR. We studied the relationship between changes in body composition, eGFR and measured GFR (mGFR), and BP during semaglutide treatment. [METHODS] We performed a prespecified analysis of a randomized placebo-controlled double-blind clinical trial in 101 adults with CKD with overweight status or obesity and without type 2 diabetes. Participants were randomized to 24 weeks of semaglutide 2.4 mg/wk subcutaneously or matched placebo treatment. We measured GFR with iohexol clearance, estimated GFR with creatinine and cystatin C, and used bioimpedance spectroscopy to determine lean body mass, fat mass, and extracellular water. [RESULTS] After 24 weeks of treatment, semaglutide compared with placebo changed total body weight, lean body mass, and fat mass by -9.1 (95% confidence interval [CI], -11.0 to -7.2), -2.5 (95% CI, -6.6 to 1.6), and -3.9 (95% CI, -7.8 to 0.0) kg, respectively. No correlations were present between changes in total body weight, lean body mass, and fat mass with changes in eGFR (creatinine or cystatin C) or mGFR during semaglutide treatment (all Spearman correlation coefficients <0.23). Similar results were observed in multivariable adjusted analyses. Semaglutide compared with placebo changed extracellular water and systolic BP by -0.9 (95% CI, -1.6 to -0.1) L and -6.3 (95% CI, -10.9 to -1.7) mm Hg, respectively. Systolic BP changes during semaglutide treatment correlated with extracellular water changes (Spearman correlation 0.40; P = 0.005). [CONCLUSIONS] Semaglutide reduced lean body mass and fat mass in patients with CKD with overweight status or obesity. These changes did not correlate with changes in creatinine or cystatin C eGFR or mGFR, suggesting that body weight reductions of 10% with semaglutide do not influence GFR estimates. [CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER] ClinicalTrials.gov, NCT04889183 .
Where this record came from
| Source | Retrieved | Identifier |
|---|---|---|
| pubmed | Sep 13, 2026 | 42308057 first ingestion |