Association Between Physical Activity and Risk of Depression: A Systematic Review and Meta-analysis.
Pearce M., Garcia L., Abbas A., Strain T., Schuch FB., Golubic R., Kelly P., Khan S., Utukuri M., Laird Y., Mok A., Smith A., Tainio M., Brage S., Woodcock J.
IMPORTANCE: Depression is the leading cause of mental health-related disease burden and may be reduced by physical activity, but the dose-response relationship between activity and depression is uncertain. OBJECTIVE: To systematically review and meta-analyze the dose-response association between physical activity and incident depression from published prospective studies of adults. DATA SOURCES: PubMed, SCOPUS, Web of Science, PsycINFO, and the reference lists of systematic reviews retrieved by a systematic search up to December 11, 2020, with no language limits. The date of the search was November 12, 2020. STUDY SELECTION: We included prospective cohort studies reporting physical activity at 3 or more exposure levels and risk estimates for depression with 3000 or more adults and 3 years or longer of follow-up. DATA EXTRACTION AND SYNTHESIS: Data extraction was completed independently by 2 extractors and cross-checked for errors. A 2-stage random-effects dose-response meta-analysis was used to synthesize data. Study-specific associations were estimated using generalized least-squares regression and the pooled association was estimated by combining the study-specific coefficients using restricted maximum likelihood. MAIN OUTCOMES AND MEASURES: The outcome of interest was depression, including (1) presence of major depressive disorder indicated by self-report of physician diagnosis, registry data, or diagnostic interviews and (2) elevated depressive symptoms established using validated cutoffs for a depressive screening instrument. RESULTS: Fifteen studies comprising 191 130 participants and 2 110 588 person-years were included. An inverse curvilinear dose-response association between physical activity and depression was observed, with steeper association gradients at lower activity volumes; heterogeneity was large and significant (I2 = 74%; P