USA: Decreased percentage of REM sleep increases risk of mortality, suggests a recent study in the journal JAMA Neurology.
Rapid eye movement (REM) sleep is linked to better health outcomes but not much is known about the association between REM sleep and mortality. Eileen B. Leary, Stanford University, Palo Alto, California, and colleagues investigated whether REM sleep is associated with mortality risk in 2 independent cohorts and to explore whether another sleep stage could be driving the findings.
The study used data from the Outcomes of Sleep Disorders in Older Men (MrOS) Sleep Study and Wisconsin Sleep Cohort (WSC). WSA began in 1988 and MrOS participants were recruited from December 2003 to March 2005. The study included WSC and MrOS participants who had REM sleep and mortality data. Analysis began May 2018 and ended December 2019.
The primary outcome was all-cause and cause-specific mortality confirmed with death certificates.
The MrOS cohort included 2675 individualsand was followed up for a median (interquartile range) of 12.1 years. The WSC cohort included 1386 individuals and was followed up for a median (interquartile range) of 20.8 years.
Key findings of the study include:
MrOS participants had a 13% higher mortality rate for every 5% reduction in REM sleep after adjusting for multiple demographic, sleep, and health covariates. .
Results were similar for cardiovascular and other causes of death. Possible threshold effects were seen on the Kaplan-Meier curves, particularly for cancer; individuals with less than 15% REM sleep had a higher mortality rate compared with individuals with 15% or more for each mortality outcome with odds ratios ranging from 1.20 to 1.35.
Findings were replicated in the WSC cohort despite younger age, inclusion of women, and longer follow-up (hazard ratio, 1.17).
A random forest model identified REM sleep as the most important sleep stage associated with survival.
"Decreased percentage REM sleep was associated with greater risk of all-cause, cardiovascular, and other noncancer-related mortality in 2 independent cohorts," concluded the authors.
The study, "Association of Rapid Eye Movement Sleep With Mortality in Middle-aged and Older Adults," is published in the journal JAMA Neurology.
DOI: https://jamanetwork.com/journals/jamaneurology/article-abstract/276771