Chronic Diarrhea and Constipation Are More Common in Depressed Individuals

Depression is a major health issue in the United States and is highly comorbid with gastrointestinal conditions. We collected data from the National Health and Nutrition Examination Survey (NHANES), a representative sample of the US population, to study the relationship between depression and bowel habits.

Using data from the NHANES (2009-2010), we identified 495 depressed and 4709 non-depressed adults who filled out the Bowel Health Questionnaire. Depression was defined according to a validated questionnaire. We used multivariable analysis, controlling for clinical and demographic variables, to evaluate the relationship between mood and bowel habits.

In our weighed sample, 24.6% of depressed individuals and 12.6% of non-depressed individuals reported disordered bowel habits. Chronic diarrhea was significantly more prevalent in depressed individuals (15.53%; 95% CI, 11.34%-20.90%) than non-depressed individuals (6.05%; 95% CI, 5.24%-6.98%; P = .0001). Chronic constipation was also more common in depressed individuals (9.10%; 95% CI, 7.02%-11.69%) than non-depressed individuals (6.55%; 95% CI, 5.55%-7.70% CI; P = .003). Mean depression scores in patients with chronic diarrhea (4.9 ± 5.8) and with chronic constipation (4.4 ± 4.93) were significantly higher than mean depression scores for individuals with normal bowel habits (3.2 ± 4.6) (P < .001). Moderate and severe depression were significantly associated with chronic diarrhea but not chronic constipation. Only mild depression was significantly associated with chronic constipation.

In an analysis of the NHANES database, we found a higher proportion of depressed individuals to have chronic diarrhea and constipation than non-depressed individuals; chronic diarrhea was more strongly associated with depression. Our findings provide support for the relationship between mood and specific bowel habits, accounting for multiple co-variables in a large sample of the general US population.