Associations of Long-term Sleep Duration Trajectories with Overall and Cause-Specific Mortality Among Middle-to-older Aged Black and White Adults.

ABSTRACT

Background: Both short and long sleep durations are adversely associated with numerous chronic conditions, including cardiovascular disease (CVD), diabetes, hypertension, and mortality. The American Academy of Sleep Medicine recommends adults in the United States sleep at least 7 hours and less than 9 hours per night to maintain optimal health. It remains unclear how sleep duration trajectories over time are associated with mortality. Methods: This observational cohort study includes 46,928 Black and White adults (mean age 53 ± 9 years) who enrolled in the Southern Community Cohort Study between 2002-2009 and completed a follow-up survey in 2008-2013. Participants were categorized into nine sleep duration trajectory categories based on the reported average sleep duration between study enrollment and at follow-up. Participant vital status and date and cause of death were ascertained via linkage to the National Death Index through 2022. Cox regression analysis was performed to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between sleep duration trajectory and all-cause and cause-specific mortality (CVD, cancer, and neurodegenerative disease) after adjustment for sociodemographic characteristics, health behaviors, and clinical factors. Results: During a median 12.6 years of follow-up, we documented 13,579 deaths, including 4,135 from CVD, 3,067 from cancer, and 544 from neurodegenerative diseases. Compared to the optimal sleep duration trajectory (maintaining 7-9 hours), all sub-optimal trajectories were associated with significant 6 to 33% greater risk of all-cause mortality in fully adjusted models. Compared to the optimal sleep trajectory, three of the sub-optimal trajectories were associated with increased CVD mortality, with HRs ranging from 1.20 to 1.34. The short-long trajectory was associated with the greatest risk of all-cause mortality (HR1.33; 95%CI 1.21, 1.46) and the long-short trajectory was associated with the greatest CVD mortality risk (HR1.34; 95%CI 1.10, 1.65). The healthy-long trajectory was associated with the greatest risk of cancer mortality (HR 1.19; 95%CI1.00, 1.41). None of the sub-optimal trajectories was associated with neurodegenerative disease mortality. Conclusions: Suboptimal sleep duration trajectories were associated with increased risk of all-cause mortality as well as CVD mortality. Findings highlight the importance of maintaining healthy sleep duration throughout midlife to reduce mortality risk.