title: Sleep duration and falls: a systemic review and meta-analysis of observational studies.
abstract: Several epidemiological studies have linked sleep duration with falls; however, the findings yielded inconsistent results. No quantitative analysis has specifically assessed the influence of sleep duration on falls. PubMed and Embase were screened for observational studies from inception to 13 September 2016. A generic inverse-variance method was used to pool the outcome data for sleep duration categories of the lowest category versus reference, and the highest category versus reference with a random-effects model. Dose-response analysis was performed to evaluate the potential relationship of sleep duration with falls. Finally, seven eligible observational studies involving a total of 212 829 participants were included in the present meta-analysis. Compared with the reference category, both short and long sleep duration were significantly associated with falls, and the pooled odds ratios (95% confidence intervals) were 1.32 (1.21, 1.46) and 1.35 (1.17, 1.56), respectively, both with evidence of significant heterogeneity. An approximately 'U-shaped' curve was observed, and the lowest risk of falls was shown at 7-8 h day-1of sleep duration. Further subgroup analysis found that the association of long sleep duration and falls was more pronounced among Caucasians. The present study is limited to its small number of included studies, considerable heterogeneity, observational study design and the large contribution of a single article. Further researches are still needed to confirm the causal association between sleep duration and falls in populations with different gender, age and ethnicity.
authors.affiliation: Department of Epidemiology, Institute of Geriatrics, Chinese People's Liberation Army General Hospital, Beijing, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Nanomedicine, Houston Methodist Research Institute, Houston, USA.
authors.forename: Dali
authors.initials: D
authors.lastname: Sun
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data*; D005006:Ethnicity; D006801:Humans; D064887:Observational Studies as Topic; D016017:Odds Ratio; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000453:epidemiology*; D013997:Time Factors; D044465:White People
keywords: epidemiology; excessive sleep; quantitative analysis; risk of falls; sleep deprivation