Research

Mixed

Sleep irregularity, measured by the Sleep Regularity Index (SRI), is significantly associated with increased cardiometabolic risk, including higher 10-year atherosclerotic cardiovascular disease (ASCVD) risk, obesity, hypertension, and markers of type 2 diabetes (fasting glucose, HbA1c), independent of sleep duration.

Track your sleep consistency, not just duration. Use a wearable or app to calculate your Sleep Regularity Index (SRI) or simply aim to go to bed and wake up at the same time every day, including weekends. This consistency is linked to lower risks of heart disease, diabetes, and obesity, independent of how many hours you sleep.

GoodSupportsHIGH confidence
Greater sleep irregularity was also correlated with 10-year risk of cardiovascular disease and greater obesity, hypertension, fasting glucose, hemoglobin A1C, and diabetes status.
Jessica R. Lunsford‐Avery et al. · Scientific Reports · 2018

Why this rating

Large sample size (n=1978), diverse population, and rigorous statistical controls, but the study is observational/cross-sectional, preventing causal inference.

Source

Validation of the Sleep Regularity Index in Older Adults and Associations with Cardiometabolic Risk

Jessica R. Lunsford‐Avery et al. · Scientific Reports · 2018

DOI 10.1038/s41598-018-32402-5

cohort · n=1978Cited 223×
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DOI resolved against Crossref · corpus check 2026-06-10

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