Sleep and frailty risk: a systematic review and meta-analysis.

Purpose: Studies on the association between sleep and frailty risk have yielded contradictory outcomes. Therefore, a systematic review and meta-analysis were designed to examine the relationship between sleep and frailty risk.

Methods: Relevant studies were identified by searching PubMed, Embase, and Scopus databases until 30 November 2019. Data were available from ten studies. Selected articles were published between 2009 and 2019. The odds ratios of 41,233 individuals were used for the meta-analysis.

Results: Pooled analysis demonstrated that when compared to the reference category of 6 to 8 hours nightly sleep duration, both the highest category (more than 8 hours, OR 1.21; 95% CI 1.10-1.32) and lowest category of sleep (under 6 hours, OR 1.13; 95% CI 1.08-1.18), were significantly correlated with increased risk of frailty. Furthermore, daytime drowsiness (OR 1.25; 95% CI 1.02-1.52), sleep disordered breathing (OR 1.28; 95% CI 1.03-1.58), and prolonged sleep latency (OR 1.18; 95% CI 1.06-1.31) enhanced the risk of frailty. Subgroup analyses by frailty status suggest that a shorter sleep duration was associated with risk of frailty but not pre-frailty. However, prolonged sleep time was significantly related with enhanced risk of pre-frailty and frailty. In addition, subgroup analyses via sex revealed that longer and shorter sleep durations increased risk of frailty in both men and women.

Conclusion: The present study revealed that longer and shorter sleep durations are associated with increased risk of frailty.