GLP-1 Evidence

Not medical advice. A record of published research and our assessments of it. The limits

Real-World Anthropometric Outcomes, Safety, and Use Patterns of GLP-1 and Dual GIP/GLP-1 Receptor Agonists in Obesity and Glucose Metabolism Disorder: A Nationwide Multicentre Community Pharmacy Study

Design
Design unknown · 531 participants · Intermediate outcome
Match to healthy normal-weight adults aged 55–75
Different populationINDIRECT: all participants were treated for obesity (52.2%) or a glucose metabolism disorder, including 200 with type 2 diabetes; mean age 56.5.
Could weight loss explain it?
Not applicableNot applicable: the main outcome is body weight itself.
Study tier
Study tier 4VERY_LOW: an uncontrolled cross-sectional study of treated users with self-reported baseline weight, closest to a case series.
Assessment
Version 3 · Two reviewers differed; settled by a recorded ruling · Oct 19, 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.

This study surveyed 531 adults collecting GLP-1 or dual GIP/GLP-1 drugs at Spanish community pharmacies for obesity or blood-sugar disorders (mean age 56.5, 66.7% women). Compared with the starting weight people recalled, they had lost on average 12.17 kg, and weight loss did not differ significantly between drugs in unadjusted analysis. Stomach and bowel side effects were the most common, and no drug-specific side-effect link held after correcting for multiple tests. With no untreated comparison group and self-reported starting weights, this describes observed change rather than proving the drugs' effect.

01Findings

What the study reported

Drugs
Glp-1 receptor agonists, Dual gip/glp-1 receptor agonists
Dose
various
Comparator
none (within-patient change from treatment initiation; treatment groups compared with each other)
Primary outcome
Change in body weight and BMI, with safety (suspected adverse drug reactions) and use patterns
Effect
Mean body weight reduction 12.17 ± 10.64 kg (11.71% ± 9.40%); 73.9% reached ≥5% and 54.1% ≥10% weight loss; no unadjusted difference in relative weight loss across treatment groups; digestive reactions lower with increasing age (adjusted OR = 0.97 per year)
95% confidence interval
not reported in abstract
Follow-up
Not stated
Adverse events
Suspected gastrointestinal adverse reactions were most common; nominal crude associations (Wegovy with nausea/vomiting, Mounjaro with constipation) did not survive multiple-testing correction; older age was linked to lower odds of digestive reactions (adjusted OR = 0.97 per year).
Limitations
Baseline weight self-reported and unverified; cross-sectional design with no untreated comparator; treatment groups differ in duration, indication, size and dose, so the findings are not causal estimates.

Who was studied

Mean age
56.5 ± 12.5 years
Sex distribution
66.7% women
Obesity status
mixed (52.2% with obesity)
Diabetes status
mixed (200 with type 2 diabetes mellitus and 54 with prediabetes/fasting glucose disturbance)
Cvd status
not reported in abstract
Ckd status
not reported in abstract
Baseline condition
obesity or glucose metabolism disorder
Sample size
531
Inclusion exclusion
adults receiving GLP-1 or dual GIP/GLP-1 receptor agonists at Spanish community pharmacies, consecutively enrolled

Study quality details

Study design
Unknown
Sample size
531
Randomization
no
Blinding
n/a
Comparator
none (within-patient change from treatment initiation; treatment groups compared with each other)
Follow up duration
not stated
Outcome type
intermediate
Replication
not assessed
Consistency with other evidence
not assessed
Population applicability
INDIRECT
Statistical precision
SDs and one adjusted OR with CI (95% CI 0.96-0.99); no CI for the weight change; baseline weight self-reported
Risk of bias
not assessed
Funding conflicts
unclear
Peer review status
yes
02Funding

Funding and conflicts

Funding
not reported in abstract
Industry funded
Unclear
Manufacturer
not stated in source
Sponsor role
not reported in abstract
Author conflicts
not reported in abstract
Independent replication
unknown

Funding is shown on every study and never used to score it.

04Source

The source, as retrieved

Abstract

[BACKGROUND] Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have transformed the management of obesity and type 2 diabetes mellitus (T2DM). Although randomized clinical trials have demonstrated substantial weight loss and metabolic benefits with incretin-based therapies, real-world evidence is needed to characterize anthropometric outcomes, safety, prescribing patterns, and treatment use under routine clinical conditions. [OBJECTIVES] The objective of this study was to characterize real-world anthropometric outcomes, safety, and use patterns of GLP-1 receptor agonists and dual GIP/GLP-1 receptor agonists in patients with obesity or glucose metabolism disorder receiving treatment through Spanish community pharmacies. [METHODS] A nationwide multicentre cross-sectional study with retrospective data collection was conducted between January and April 2026 across community pharmacies in Spain. Adult patients receiving GLP-1 receptor agonists or dual GIP/GLP-1 receptor agonists were consecutively enrolled and classified according to therapeutic indication (obesity or glucose metabolism disorder). Changes in body weight and body mass index (BMI) were assessed using paired-sample t-tests, while multivariable linear regression explored independent determinants of weight loss. Crude safety signals were initially evaluated using exploratory crude safety association analysis based on Odds Ratios (ORs). Subsequently, multivariable logistic regression was performed to identify independent predictors of suspected digestive adverse drug reactions after adjustment for demographic characteristics, treatment-related variables, lifestyle factors, and concomitant glucose-lowering therapies. Baseline body weight was retrospectively reported by participants and was not independently verified against clinical records or other objective sources, whereas current body weight was measured by the pharmacist at the study visit. [RESULTS] A total of 531 patients were included (52.2% with obesity; 47.8% were classified in the glucose metabolism disorder (GMD) cohort, comprising 200 patients with type 2 diabetes mellitus and 54 with prediabetes/fasting glucose disturbance; the mean age was 56.5 ± 12.5 years; and 66.7% were women). The mean observed reduction in body weight from treatment initiation to the study assessment was 12.17 ± 10.64 kg, corresponding to an 11.71% ± 9.40% reduction relative to retrospectively reported baseline weight. Overall, 73.9% and 54.1% of participants achieved ≥5% and ≥10% weight loss, respectively. No statistically significant unadjusted difference in relative weight loss was detected across treatment groups; however, equivalence was not formally assessed. Gastrointestinal suspected adverse drug reactions were the most frequently reported safety outcomes. Exploratory crude analyses showed nominal associations between Wegovy® and nausea/vomiting and between Mounjaro® and constipation, as well as between concomitant insulin and dizziness and SGLT2 inhibitor therapy and urinary disorders; however, none of these associations remained statistically significant after Benjamini-Hochberg correction for multiple testing. In the exploratory multivariable linear regression model, treatment duration, treatment agent, dietary adherence, light physical activity, and age showed statistically significant adjusted associations with observed percentage weight loss. In the multivariable logistic regression model, increasing age was the only variable significantly associated with lower odds of reported suspected digestive adverse drug reactions (adjusted OR = 0.97 per year; 95% CI 0.96-0.99; p = 0.003). [CONCLUSIONS] Observed percentage weight loss varied across treatment groups, although between-treatment comparisons should be interpreted cautiously because of differences in treatment duration, therapeutic indication, sample size, and dose exposure. Given the retrospective ascertainment of baseline weight and the cross-sectional design, these findings should be interpreted as real-world estimates of observed weight change rather than causal estimates of treatment effectiveness. Reported suspected adverse drug reactions were common, particularly gastrointestinal events. Although several nominal associations were observed in exploratory crude analyses, none remained statistically significant after correction for multiple testing. These findings support the importance of individualized monitoring in community pharmacy settings. These findings provide a rationale for the prospective development and evaluation of a standardized pharmacy-led dispensing and follow-up protocol to support patient safety and treatment adherence.

Where this record came from

SourceRetrievedIdentifier
pubmedOct 18, 202642881794
first ingestion