U-shaped association between sleep duration with chronic constipation and diarrhea: A population-based study

To examine the association between sleep duration with chronic constipation and diarrhea, we collected demographic and questionnaire data of participants from The National Health and Nutrition Examination Survey in the period 2005 to 2010. A restricted cubic spline curve function was used to determine the association between sleep duration and chronic constipation or diarrhea. Multivariate logistic regression models were used to estimate the association between sleep duration groups and chronic constipation or diarrhea. 14,054 eligible participants were included in this study. Among all sleep durations, 7 hours sleep per day had the highest percentage of normal stool forms (86.3%, P < .001), while people with ≤4 hours sleep had a higher number of bowel movements per week (P < .001). RCS models demonstrated a significant nonlinear association between sleep duration and risk of chronic constipation (P < .001). The inflection points of the U-shaped association curve corresponded to 7 hours of sleep per day. Multivariate logistic regression indicated that compared to participants with 7 hours daily sleep duration, participants with ≤4 hours and ≥10 hours sleep duration had a 54% (95%CI: (1.16-2.04), P = .002) and 90% (95%CI: (1.33-2.72), P < .001) higher risk of constipation, respectively. There is a non-linear association between sleep duration and the risk of chronic constipation. Our findings indicate that both shorter and longer sleep duration are associated with an increased risk of constipation.