Constipation Does Not Cause Colorectal Cancer

Gastroenterologists are often asked whether constipation is a risk factor for colorectal cancer. In the current meta-analysis, investigators analyzed data from cross-sectional surveys, cohort studies, and case-control studies that evaluated the possible association between constipation and colorectal cancer.

Twenty-eight studies were considered eligible, including 8 cross-sectional, 3 cohort, and 17 case-control studies. In the cross-sectional surveys comprising 8866 patients who underwent diagnostic colonoscopy for symptoms, a primary indication of constipation versus other indications for colonoscopy was associated with a lower prevalence of colorectal cancer (pooled odds ratio, 0.56; 95% confidence interval, 0.36–0.89). In the three cohor…