Efficacy of pharmacotherapy for weight loss in adults with type 2 diabetes mellitus: A meta-analysis

Susan L. Norris, Xuanping Zhang, Alison Avenell, Edward Gregg, Christopher H. Schmid, Curi Kim, Joseph Lau

Research output: Contribution to journalReview articlepeer-review

132 Scopus citations


Background: Obesity is closely related to type 2 diabetes mellitus, and weight reduction is an important part of the care delivered to obese persons with diabetes. The objective of this review was to assess the efficacy of pharmacotherapy for weight loss in adults with type 2 diabetes. Methods: A systematic review of the literature was performed, and studies were included if pharmacotherapy was used as the primary strategy for weight loss among adults with type 2 diabetes. Published and unpublished studies with any design were included. A random effects model was used to combine outcomes from randomized controlled trials. Results: Sufficient data for the meta-analysis were available for fluoxetine, orlistat, and sibutramine. Fourteen randomized, placebo-controlled trials were included in the review, with a total of 2231 patients. Pharmacotherapy produced modest reductions in weight for fluoxetine (3.4 kg [95% confidence interval (CI), 1.7-5.2 kg] at 8-16 weeks of follow-up; 5.1 kg [95% CI, 3.3-6.9 kg] at 24-30 weeks; and 5.8 kg [95% CI, 0.8-10.8 kg] at 52 weeks); orlistat (2.6 kg [95% CI, 2.1-3.2 kg] [2.6% loss] at 52 weeks); and sibutramine (4.5 kg [95% CI, 1.8-7.2 kg] [3.3% loss] at up to 26 weeks). Glycated hemoglobin was also modestly reduced: fluoxetine (1.0% [95% CI, 0.4%-1.5%] at 8-16 weeks; 1.0% [95% 0.6%-1.4%] at 24-30 weeks; and 1.8% [95% CI, -0.2%-3.8%] at 52 weeks); orlistat (0.4% [95% CI, 0.3%-0.5%]); and sibutramine (0.7% [95% CI, -0.5%-1.9%]). Gastrointestinal adverse effects were common with orlistat; tremor, somnolence, and sweating with fluoxetine; and palpitations with sibutramine. Conclusions: Fluoxetine, orlistat, and sibutramine can achieve statistically significant weight loss over 26 to 52 weeks. However, the magnitude of weight loss was modest, and the long-term health benefits and safety remain unclear. Interventions that combine pharmacologic therapy with intensive behavioral interventions may be more effective but need additional research.

Original languageEnglish (US)
Pages (from-to)1395-1404
Number of pages10
JournalArchives of internal medicine
Issue number13
StatePublished - Jul 12 2004

ASJC Scopus subject areas

  • Internal Medicine


Dive into the research topics of 'Efficacy of pharmacotherapy for weight loss in adults with type 2 diabetes mellitus: A meta-analysis'. Together they form a unique fingerprint.

Cite this