Plain-English Summary
Sleep Regularity Mortality studied sleep regularity in UK Biobank participants with wrist accelerometer data. Higher sleep regularity was associated with a 20% to 48% lower risk of all-cause mortality across the top four SRI quintiles compared with the least regular quintile.
Key Findings
- Higher sleep regularity was associated with a 20% to 48% lower risk of all-cause mortality across the top four SRI quintiles compared with the least regular quintile.
- Higher sleep regularity was associated with lower cancer and cardiometabolic mortality across those quintiles.
- Sleep regularity was a stronger predictor of all-cause mortality than sleep duration in equivalent and nested models.
- Associations persisted after adjustment for demographic, behavioral, shift-work, socioeconomic, and health variables.
Limitations
- Observational design cannot establish causality.
- One week of accelerometer data may not represent long-term sleep regularity.
- Sleep regularity may be both a cause and marker of risk.
- UK Biobank selection limits generalizability.
Why It Matters
All-cause and cause-specific mortality by Sleep Regularity Index.
Viral Vitalism Verdict
Useful evidence, bounded by design: Observational design cannot establish causality.