Efficacy of orlistat in type 2 diabetes: a systematic review and meta-analysis

Abstract

Background: Obesity is a common comorbidity of type 2 diabetes mellitus (T2DM), a chronic metabolic condition affecting millions worldwide. Orlistat may be used to reduce weight as an adjunct to diet and lifestyle changes. Aim: To assess the evidence of orlistat on weight loss in adults with obesity and T2DM or a high risk of T2DM. Design & setting: Systematic review and meta-analysis of randomised controlled trials (RCTs) in clinical settings. Method: Articles were searched in 10 databases including MEDLINE, Embase, and PsycInfo. RCTs of orlistat in adults with T2DM or at high risk and a body mass index (BMI)≥25 kg/m2, with ≥12 weeks of follow-up and reported change in weight or BMI, were included. A random effects meta-analysis model was used to pool mean differences, I2statistics to assess heterogeneity, and a funnel plot to assess publication bias. Results: Thirty RCTs compared orlistat with a comparator, in conjunction with a weight-loss diet. All trials showed statistically significant (P<0.05) greater weight loss for the orlistat group than controls. A meta-analysis of 22 studies (n = 5921) showed that the overall weight loss for the orlistat group was a mean 2.40 kg (95% confidence interval [CI] = 2.08 to 2.72) greater than in controls. Weight difference was statistically significant (P<0.05) between subgroups at 3 months (2.74 kg, 95% CI = 1.20 to 4.27), 6 months (2.13 kg, 95% CI = 1.61 to 2.66), and 12 months (2.49 kg, 95% CI = 1.89 to 3.09). Conclusion: Orlistat resulted in statistically significant greater weight loss in overweight adults with T2DM or at high risk compared with controls. Orlistat can be considered an adjunct in T2DM or at high risk of T2DM for weight loss along with diet and lifestyle modifications.