Associations of Bowel Movement Frequency with Risk of Cardiovascular Disease and Mortality among US Women

Emerging evidence suggests a potential impact of gastrointestinal function on cardiometabolic risk. Abnormal bowel movements have been related to various cardiovascular risk factors such as dyslipidemia, hypertension, diabetes, and altered metabolism of bile acids and gut microbiota. However, little is known about whether bowel movement frequency affects risk of cardiovascular disease (CVD) and mortality. In the Nurses’ Health Study, bowel movement frequency was self-reported in 1982 by 86,289 women free from CVD and cancer. During up to 30 years of follow-up, we documented 7,628 incident CVD cases and 21,084 deaths. After adjustment for dietary intake, lifestyle, medication use, and other risk factors, as compared with women with daily bowel movement, having bowel movements more than once daily was significantly associated with increased risk of CVD (hazard ratio [HR]: 1.13; 95% confidence interval [CI]: 1.05–1.21), total mortality (HR: 1.17; 95% CI: 1.12–1.22), and cardiovascular mortality (HR: 1.17; 95% CI: 1.07–1.28). With further adjustment for body mass index and diabetes status, the association with total mortality remained significant (HR: 1.10; 95% CI: 1.06–1.15), whereas the associations with incident CVD and cardiovascular mortality were no longer significant. Our results suggest increased bowel movement frequency is a potential risk factor for premature mortality.