Defecation frequency and cardiovascular disease mortality in Japan: The Ohsaki cohort study

Abstract

Background: It has been suggested that constipation is associated with cardiovascular disease (CVD). The association between defecation frequency and CVD mortality in a large population has not been reported hitherto. The aim of this study was to examine whether defecation frequency is related to CVD mortality.

Methods and results: A total of 45,112 eligible Japanese men and women aged 40-79 years participated in the Ohsaki Cohort study. Defecation frequency was evaluated at the baseline using a self-administered questionnaire. Hazard ratios (HRs) and 95% confidence intervals (CIs) for cardiovascular disease mortality were calculated according to defecation frequency (≥ 1 time/day, 1 time/2-3 days, ≤ 1 time/4 days) by the Cox proportional hazards model. During 13.3 years of follow-up, 2028 participants died due to CVD. Compared with those in the ≥ 1 time/day group, the risk of overall CVD mortality was significantly higher in the 1 time/2-3 days and ≤ 1 time/4 days groups; the multivariate HR (95%CI) for 1 time/2-3 days and ≤ 1 time/4 days was 1.21 (95% CI: 1.08-1.35) and 1.39 (95% CI: 1.06-1.81), respectively.

Conclusion: A lower defecation frequency was associated with risk of CVD mortality in this Japanese population. Future studies, aiming at elucidating the mechanisms underlying the associations between chronic constipation and risk of CVD mortality, may be facilitated by our findings.

Keywords: Cardiovascular disease mortality; Cohort study; Defecation frequency; Japan.