Exercise for Depressive Symptoms in Parkinson Disease: A Systematic Review and Meta-analysis of Randomized Controlled Trials

To evaluate the efficacy of physical exercise in improving depressive symptoms in Parkinson disease (PD).We conducted a systematic review of randomized controlled trials (RCTs) following a prespecified protocol guidance (PROSPERO CRD42021243142). Two independent authors searched for studies in MEDLINE, Cochrane Register of Controlled Trials, Physiotherapy Evidence Database, Embase, PsycINFO, and Sports Discus from database inception to June 2022.Two independent authors extracted the data and evaluated the risk of bias using the revised Cochrane risk of bias tool. We performed random-effects meta-analyses and rated the certainty of evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.A total of 36 RCTs met the inclusion criteria, 14 of which were pooled in the quantitative synthesis. Depression symptomatology significantly decreased in the exercise group compared with usual care (standardized mean difference [SMD], -0.49; 95% confidence interval [CI], -0.74 to -0.24; very low quality of evidence; 14 RCTs; 961 participants). Physical exercise also improved patients' quality of life (SMD, -0.51; 95% CI, -0.81 to -0.21; 7 RCTs; 485 participants). As for acceptability, we did not find any difference between exercise and usual care (relative risk, 1.01; 95% CI, 0.97 to 1.05; 12 RCTs; 1048 participants). We judged all the studies except 2 to be at high risk of bias.Results from our systematic review identify physical activity as a viable option to reduce depressive symptoms in PD. Future clinical practice guidelines should consider physical exercise in their recommendations for depression symptomatology reduction in people with PD.