Effects of weight loss medications on mortality and cardiovascular events: A systematic review of randomized controlled trials in adults with overweight and obesity

AimsAdults affected by obesity are at higher risk of premature mortality. Medications can help to lose weight and to maintain weight loss. Aim of this meta-analysis was to assess whether anti-obesity medications affect all-cause mortality, mortality due to cardiovascular events, cardiovascular risk factors and body weight.Data synthesisA Medline search was performed to identify randomized controlled trials (RCTs) of anti-obesity medications in adults with overweight or obesity reporting data on all-cause mortality, cardiovascular mortality or non-fatal cardiovascular events, with a follow-up of at least 6 months. We identified 28 RCTs with 50,106 participants. The median follow-up was 52 weeks. Evidence did not show superiority of anti-obesity medications over placebo in reducing all-cause mortality (risk ratio 1.03, 95%Confidence Interval CI] 0.87 to 1.21) or cardiovascular mortality (risk ratio 0.92, 95%CI 0.72 to 1.18). All-cause mortality rate was positively associated with weight loss (β = 0.0007; p = 0.045); hence, for each kg of body weight lost there was a 0.07% decrease of all-cause mortality. The pharmacological treatment reduced total-cholesterol (7.15 mg/dl; 95%CI 1.46–12.85), LDL-cholesterol (5.06 mg/dl; 95%CI 1.12–9.00), and triglycerides levels (9.88 mg/dl; 95%CI 5.02–14.75), while it increased HDL-cholesterol (1.37 mg/dl; 95%CI 0.17–2.57). Systolic blood pressure decreased (0.90 mmHg; 95%CI 0.15–1.64).ConclusionsAlthough we were unable to demonstrate a superiority of anti-obesity medications over placebo on mortality, metaregression showed that even a small weight reduction tends to reduce all-cause mortality in obesity. Our data support public health measures to reduce the obesity burden by including the use of anti-obesity medications.Registration number (PROSPERO)CRD42020210329.