Potential biopsychosocial factors mediating/moderating the relationship between depressive symptoms and body size among children and adolescents: A systematic review

Summary The prevalence of depression and obesity in the pediatric population has increased along with multiple adverse health outcomes in later life. However, the mechanisms underlying the bidirectional relationship between obesity and depression have not yet been clarified. We aim to systematically summarize the literature reporting on mediational or moderational biopsychosocial factors in the relationship between depression and body size among children and adolescents. Four electronic databases (PubMed, Web of Science, PsycINFO, and PsychArticles) were systematically searched from inception until December 23, 2021, and subsequently updated until June 9, 2023. The study protocol was registered with PROSPERO (CRD42022301475). A total of 36 unique records reporting 152,513 children and adolescents meeting the inclusion criteria were identified. The results indicate that disparate psychological variables (e.g., body image, victimization and bullying, eating disorders, and sleep problems) may mediate the bidirectional relationship between depressive symptoms and body size. Moreover, the mediational/moderational effect of biological factors has not been well established. The moderational effect of social factors was inconsistently reported. Future research should aim to identify and characterize factors that may impact the bidirectional relationship between depression and obesity to inform prevention intervention strategies for affected children and adolescents.