Overview
- Adults who identified as definite evening types had a 16% higher risk of first heart attack or stroke over roughly 14 years compared with intermediate chronotypes, according to a JAHA study.
- Poor overall cardiovascular health scores were 79% more prevalent in evening types, while morning types were 5% less likely to have poor scores than intermediates.
- About three-quarters of the chronotype–cardiovascular link was explained by American Heart Association Life’s Essential 8 factors, with nicotine exposure accounting for the largest share at ~34%.
- Evening types showed worse scores across several components, notably nicotine use and sleep, and also reported lower physical activity and poorer diet than intermediate types.
- Authors cautioned that single-time self-reported chronotype and one-time health measurements, plus the predominantly White UK Biobank cohort, limit causal claims and generalizability.