Cooccurrence and bidirectional prediction of sleep disturbances and depression in older adults: Meta-analysis and systematic review

•Sleep disturbances and depression cause tremendous health burdens and adverse consequences as the worldwide population ages.•A high prevalence of sleep disturbances, depression and their coexisting were found in community-dwelling older adults.•This review provides evidence of the bidirectional predictive relationship between sleep disturbances and depression in older adults.•This review emphasizes the importance of timely interventions in incipient sleep disturbances and depression among older adults.•Approaches that target the common pathophysiology of sleep disturbances and depression may improve clinical outcomes among older adults.

The present study pooled the prevalence of sleep disturbances and depression in community-dwelling older adults (mean age ≥ 60 years) and quantified the strength of evidence of the relationship between these two problems. From 23 cross-sectional studies and five sets of baseline data, a high pooled prevalence of sleep disturbances (30.5%), depressive symptoms (18.1%) and coexisting disorders (10.6%) were found. In the 23 cohort studies, self-reported sleep disturbances increased the risk of the onset of depression (relative risk [RR] = 1.92). Persistent sleep disturbances increased the risk of the development (RR = 3.90), recurrence (RR = 7.70), and worsening (RR = 1.46) of depression in older adults. Little support was found for a predictive role for objective sleep characteristics in the development of depression. Older adults with depression had a higher risk of developing (RR = 1.72) and worsening (RR = 1.73) symptoms of sleep disturbances. This review emphasizes the importance of timely interventions in incipient sleep disturbances and depression among older adults, preventing the development of more serious comorbidities.