BMJ Open · Nov 2, 2026
Exploring the potential association between sleep irregularity and mortality: a protocol for a systematic review and meta-analysis
By Arora T, Arshad K, Alnaqbi F et al.
Introduction Sleep behaviour is multifaceted, and much sleep-health research has focused on understanding the contribution of sleep duration and sleep quality. Irregular sleep-wake timing is a recent and emerging field that has been linked to the onset and exacerbation of multiple chronic diseases. Several studies have assessed the relationship between irregular sleep and all-cause and specific-cause mortality but to date, no systematic review or meta-analysis has been published in this area. It is crucial to determine if sleep irregularity is associated with mortality, and to what extent, particularly as life expectancy is now longer but individuals are now living with chronic diseases. Methods and analysis A total of five databases will be searched, including PubMed, PsycINFO, Embase, Web of Science and Scopus. A search strategy has already been developed to retrieve articles relevant to the study. No date or language restrictions will be applied. Articles retrieved from the search will be independently screened by two team members to determine whether they meet the predefined inclusion criteria. Titles and abstracts will be screened initially and full-text articles will be subsequently screened to determine the final inclusion/exclusion status of each article using Covidence software. Data extraction will also be performed and the risk of bias will be evaluated using the Newcastle-Ottawa Scale. Ethics and dissemination Our study does not require collection of new data but is a review of previously published data; therefore it is not necessary to obtain ethical approval for our study. The findings of our systematic review and meta-analysis will be published in an appropriate peer-reviewed journal. PROSPERO registration number Our prospective review is registered with PROSPERO (registration number: CRD420261324603). Any eventual amendment of the protocol will be recorded in the PROSPERO registration and in the final review.