Weight‐reducing treatments are associated with an improvement in depression, functional health status, and quality of life: A meta‐analysis of randomized controlled trials

Aim: To assess whether there is a beneficial or detrimental effect of weight reduction on mental health. Materials and methods: Meta-analysis of randomized trials performed for weight loss, in which weight loss at endpoint was greater than 5% in the intervention arm and smaller than 5% in the control arm, obtained with any surgical, endoscopic, or EMA-approved pharmacological intervention. The endpoints were the incidence of overall and specific psychiatric adverse events. Results: Weight loss was associated with a reduced risk of major depression (MH-OR 0.45 95% CI [0.21, 0.94], I2 = 0), and overall depression (MH-OR 0.72 [0.54, 0.97]); in subgroup analyses, a weight loss greater than 10% was associated with a lower incidence of depression than smaller weight loss (p = 0.04), whereas no difference was found between different interventions. No difference was detected in the incidence of anxiety (MH-OR 1.04 [0.78, 1.39]), of serious (M-H, OR CI 1.07 [0.78, 1.47]) and overall (MH-OR 1.09 [0.89, 1.34]) psychiatric adverse events, suicidal ideation (M-H, OR 0.87 [0.44, 1.70]), or suicide (M-H, OR 0.87 [0.44, 1.70]). An improvement in functional health status was detected, either as SF-36 Mental (SMD-IV 0.45 [0.37, 0.52]) or SF-36 Physical function (SMD-IV 0.29 [0.14, 0.44]) or IWQOL Lite Physical function (MD-IV 3.96 [1.60, 6.32]). Conclusion: Weight-reducing treatments were associated with a beneficial effect on quality of life and functional health status and a reduced risk of depression, without any safety signal for serious or non-serious psychiatric adverse events.