Short-term effect of a negative colonoscopy in patients with functional constipation

The yield of colonoscopy for neoplasia among patients with chronic constipation is very low. However, a negative colonoscopy may benefit these patients by decreasing anxiety and thereby alleviating constipation symptoms. We performed a prospective study to characterize the effect of a negative colonoscopy in patients with functional constipation. Seventy-five patients with chronic constipation were enrolled, and 69 patients were diagnosed with functional constipation through the Rome III criteria. After excluding patients whose constipation symptoms were affected by medications (e.g., laxatives, prokinetics), 45 patients were included in the study. Among the 45 patients, the average health-related anxiety score decreased from 21.0 to 15.6 at 1 week after colonoscopy (P < 0.01). Sustained improvement was observed in anxiety scores at 1 month (14.0), 2 months (12.4), and 6 months (11.2). Mean constipation symptom score was also decreased at 1 week (8.7), 1 month (8.0), 2 months (7.6), and 6 months (6.8) compared with the precolonoscopy period (11.5; P < 0.01). These results suggest that a negative colonoscopy in patients with functional constipation is associated with a decline in health-related anxiety and constipation symptom scores. (Registration number: ChiCTR-OOh-16008488).