Effects of different sleep disorders on frailty in the elderly: a systematic review and meta-analysis of observational studies

Study objectives Frailty is frequently reported following sleep disorders; however, the extent to which sleep disorders influence frailty remains unclear. In the current study, we performed a meta-analysis to evaluate the quantitative effects of different sleep disorders on frailty in the elderly. Methods We conducted a systematic search of several databases, including PubMed, Web of Science, Embase, and Scopus, to retrieve articles published from May 2009 to June 2021. The data outcomes are expressed as the odds ratio (OR) and 95% confidence interval (CI). Results Eighteen studies were included, with 39669 participants. Older adults with sleep disorders were found to have a higher risk of frailty (pooled OR= 1.49, 95%CI =1.35-1.64, p < 0.01). Specifically, daytime sleepiness (pooled OR = 1.69, 95%CI = 1.09-2.61, p < 0.01), short sleep duration (pooled OR = 1.36, 95%CI =1.20-1.54, p= 0.45), long sleep duration (pooled OR =1.99, 95%CI = 1.39-2.85, p = 0.02), sleep latency extension (pooled OR =1.38, 95%CI = 1.19-1.60, p= 0.72), and sleep disordered breathing (pooled OR =1.30, 95%CI = 1.11-1.53, p= 0.37) were correlated with frailty. Conclusions The risk of frailty differs between older adults with sleep disorders and controls, suggesting that the relationships between different sleep disorders and frailty vary. These results highlight the need to monitor sleep disorders of the elderly and conduct intervention to prevent or delay the frailty process.