Weight loss effect of glucagon-like peptide-1 mimetics on obese/overweight adults without diabetes: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) benefit weight maintenance for diabetic patients. We performed a systematic review to evaluate its weight loss effect on obese/overweight patients without diabetes in randomized controlled trials (RCTs).

METHODS

Literature updated to May 5, 2014 from Cochrane Library, MEDLINE, EMBASE and reference lists from relevant articles were identified. RCTs with GLP-1 mimetics treating obese/overweight adults without diabetes for at least 12 weeks were assessed. Studies lacking primary measurements were excluded. Three authors extracted data independently. Either fixed-effect or random-effect models were used to calculate weighted mean differences (WMDs), combined relative risks (RR) and 95% confidence interval (CI) in meta-analyses. Intertrial heterogeneity across studies was examined by I(2) and Q statistics.

RESULTS

A total of 1345 individuals retrieved from eight studies were involved and all included trials were of mild-to-moderate bias risks. Participants in GLP-1RA groups achieved a larger weight loss than those in control groups (-2.85 kg, 95%CI -3.55 to -2.14), and liraglutide may work in a dose-dependent fashion. GLP-1RAs also reduced body mass index (BMI) and waist circumferences (WC) and benefited systolic blood pressure and triglyceride regulation. But GLP-1RAs were associated with increased nausea and vomiting events.

CONCLUSIONS

GLP-1 mimetics induce a weight loss in addition to BMI and WC reduction in obese/overweight adults without diabetes. Further long-term randomized trials and basic studies are required to investigate the mechanisms.

Exenatide as a Novel Weight Loss Modality in Patients Without Diabetes

Objective:

To evaluate the potential role of exenatide for weight loss in overweight or obese adults without diabetes.

Data Sources:

PubMed (1946-August 2012) and EMBASE (1974-August 2012) were used to conduct a literature search utilizing the terms exenatide, weight loss, obesity, and overweight. Additional references were identified by bibliographic review of relevant articles.

Study Selection and Data Extraction:

Studies assessing the use of exenatide in adult subjects without type 2 diabetes or polycystic ovary syndrome and reporting effects on body weight were included.

Data Synthesis:

Five studies were identified that reported use of exenatide in nondiabetic adults and included weight change as an outcomes measure. In all 5 of these studies, subjects taking exenatide experienced statistically significant weight loss, which ranged from 2.0 ± 2.8 to 5.1 ± 0.5 kg. Two of the trials were randomized, placebo-control led studies; 1 trial was a randomized, open-label investigation; 1 study had a prospective, open-label cohort design; and the remaining study was a chart review. Adverse events experienced with exenatide were primarily gastrointestinal in nature, although each trial reported the drug to be well tolerated.

Conclusions:

Obesity continues to be a national epidemic, while choices for effective pharmacologic treatments are extremely limited. Exenatide appears to have promising effects on weight in overweight or obese adults without type 2 diabetes, Further investigations with large, placebo-controlled trials assessing long-term weight loss as a primary outcome are warranted.