Association between colonic diverticulosis and bowel symptoms: A case-control study of 1629 Asian patients

Background It remains unclear whether diverticulosis, absent inflammation, is responsible for chronic bowel symptoms. We examined the association between bowel symptoms and asymptomatic diverticulosis. Method This case-control study included 543 patients with diverticulosis and 1086 age and sex-matched controls (1:2) without diverticulosis on screening colonoscopy. Eleven symptoms (abdominal discomfort, hunger discomfort, borborygmus, abdominal distension, flatus, constipation, diarrhea, loose stools, hard stools, fecal urgency, and incomplete evacuation) were evaluated using a gastrointestinal symptoms rating scale (GSRS) at baseline and second questionnaire. Associations between diverticulosis and symptoms were estimated using odds ratios (ORs) and 95 confidence interval (CI). Results In multivariate analysis, constipation (OR, 0.85 [0.78–0.93]) and hard stools (OR, 0.86 [0.78–0.94]) were negatively associated with diverticulosis. The other nine symptoms showed no association with diverticulosis. Diverticulosis was negatively associated with constipation (OR, 0.93 [0.74–0.93]), hard stools (OR, 0.85 [0.76–0.96]), and incomplete evacuation (OR, 0.88 [0.79–0.99]) in males, and positively associated with diarrhea (OR, 1.39 [1.14–1.69]) and loose stools (OR, 1.28 [1.05–1.55]) in females. No bowel symptoms were positively associated with any of right-sided, left-sided, or bilateral diverticulosis. Test–retest reliability of GSRS (mean interval, 4.4 months) was moderate (Mean Kappa, 0.568) in males and good (Mean Kappa, 0.652) in females. Conclusions This large, colonoscopy-based, case-control study demonstrated that neither constipation nor hard stools were associated with an increased risk of diverticulosis, regardless of diverticulum location. In females, but not males, diarrhea and loose stools were positively associated with diverticulosis. Long-term test–retest reliability suggested that these symptoms remain consistent over a given period.