Effect of orlistat on plasma lipids and body weight: A systematic review and meta-analysis of 33 randomized controlled trials

Orlistat, an inhibitor of intestinal lipase, promotes body weight reduction. The lipid-lowering efficacy of orlistat is controversial and the effect of orlistat-induced body weight reduction on lipid changes has not been explored in meta-regression analyses. A systematic literature search was conducted to identify randomized controlled trials investigating the efficacy of orlistat on plasma total, low-density lipoprotein and high-density lipoprotein cholesterol, triglycerides and lipoprotein(a) levels. Thirty-three studies were included in the meta-analysis (5522 and 4210 participants in the orlistat therapy and control groups, respectively). Orlistat reduced body weight (weighted mean difference: -2.12, p <0.001), total-cholesterol (weighted mean difference: -0.30mmol/L, p <0.001), low-density lipoprotein cholesterol (weighted mean difference: -0.27mmol/L, p <0.001), high-density lipoprotein cholesterol (weighted mean difference: -0.034mmol/L, p <0.001) and triglyceride (weighted mean difference: -0.09mmol/L, p <0.001) concentrations, while no effect on lipoprotein(a) was observed. Total- and low-density lipoprotein cholesterol-lowering were associated negatively with duration of orlistat treatment and positively with body weight changes. In conclusion, Orlistat treatment slightly reduces cholesterol and triglyceride levels, but not lipoprotein(a) levels. Total- and low-density lipoprotein cholesterol levels reductions are more consistent in patients with greater body weight reduction and shorter duration of orlistat treatment