Associations between Supper Timing and Mortality from Cardiovascular Disease among People with and without Hypertension

Aim: Less is known about the impact of supper time on cardiovascular disease (CVD) risk among hypertensives and nonhypertensives. We aimed to explore this issue in a cohort study. Methods: W e analyzed the data of 72,658 participants (15,386 hypertensives and 57,272 nonhypertensives) aged 40-79 years without a history of CVD at baseline (1988-1990) under the Japan Collaborative Cohort study. Supper time was assessed based on self-reported questionnaires categorized as before 17:00, between 17:00 and 20:00, after 20:00, irregular supper time, and reference supper time (17:00-20:00). Hazard ratios (HRs) and 95% confidence intervals (95% CI) of CVD mortality were calculated according to supper time after adjustment for potential confounders, stratified by hypertensive status and age group (<65 and >_ 65 years). Results: During a median of 19.4 years of follow-up, 4,850 CVD deaths were recorded. Compared with the reference time, the risk of CVD mortality was higher for irregular supper time for the total population, either hypertensives or nonhypertensives, more specifically hypertensives aged >= 65 years; the multivariable HR (95% CI) of CVD mortality in the total population was 1.28 (1.11-1.50, P<0.01). The supper time of >20:00 tended to be associated with the higher risk only for hypertensives; the multivariable HR was 1.39 (0.98-1.96, P=0.06). Conclusion: Irregular supper time was associated with an increased risk of CVD mortality. Supper timing could be a surrogate marker for CVD risk.