Among 4266 US adults with advanced (Stage 3-4) CKM syndrome, long sleep (>8 hours) was associated with higher cardiovascular mortality and borderline higher all-cause mortality, short sleep was not significantly associated with either outcome, and sleep time showed a U- or J-shaped association with death rates.
Long sleep (>8 hours/night) was significantly associated with higher cardiovascular mortality in adults with advanced CKM syndrome compared with 7-8 hours of sleep.
Long sleep was borderline significantly associated with higher all-cause mortality.
Short sleep (<7 hours/night) was not significantly associated with all-cause or cardiovascular mortality.
Restricted cubic spline analysis showed a U-shaped nonlinear association between sleep time and overall mortality.
The study was a prospective cohort analysis of NHANES 2005-2018 participants with advanced (Stage 3-4) CKM syndrome.
The authors conclude that sleep time should be considered an important health marker in managing advanced CKM syndrome and that long sleepers need additional clinical assessment.
This study followed 4266 US adults with advanced cardiovascular-kidney-metabolic (CKM) syndrome, a combination of heart, kidney, and metabolic problems. The adults were drawn from a national health survey and followed for a median of about 7.6 years. The researchers asked whether the amount of sleep people reported was linked to their risk of dying from any cause or from cardiovascular disease. People who slept more than 8 hours a night had about a 53% higher risk of cardiovascular death than those who slept 7-8 hours. Their risk of death from any cause was about 21% higher, a result right at the edge of statistical significance. People who slept less than 7 hours did not have a significantly different risk. Overall, the relationship between sleep and death risk was U- or J-shaped, with risk rising at the long-sleep end. This research suggests that sleep duration may be a useful marker of health risk in people with advanced CKM syndrome, and that long sleep may signal a need for closer clinical attention. The study is observational and relies on self-reported sleep, so it cannot show that long sleep causes death. Long sleep may instead reflect underlying illness.
Xiong Y, Yin Y, Wang J, Lan K, Liang J, Han W. (2026). Association of sleep time with all-cause and cardiovascular mortality among individuals with advanced cardiovascular-kidney-metabolic syndrome: A NHANES-based prospective cohort study.. Medicine. https://doi.org/10.1097/MD.0000000000051259