Chronic idiopathic constipation: more than a simple colonic transit disorder

Constipation affects up to 28% of Americans in 4 pathophysiologic patterns: slow transit constipation, dyssynergic defecation, a combination of both, and normal colon transit with normal pelvic floor function. Constipation may be a part of a generalized gastrointestinal (GI) tract transit disorder. The purposes of this study were to determine the percentage of constipated patients with the different pathophysiologic subtypes and and to evaluate what percentage of constipated patients has a diffuse GI tract transit disorder.

This was a retrospective analysis of 212 patients who underwent anorectal manometry for intractable constipation. Results of anorectal manometry, electromyography, balloon expulsion testing, defecography, and whole-gut transit scintigraphy were reviewed.

Of 212 patients included in the analysis, 91 (42%) had slow transit constipation, 25 (12%) had dyssynergic defecation, 53 (25%) had both, and 43 (20%) had neither. Of patients (91) with slow transit constipation alone, 31 (34%) had delayed gastric emptying, 9 (10%) had delayed small bowel transit, 7 (8%) had a delay in both, and 41 (48%) had normal upper GI tract transit. A similar distribution of upper GI tract transit disorders was observed for patients with dyssynergic defecation, slow transit constipation and dyssynergic defecation, and normal colon transit with normal pelvic floor function.

Patients with chronic idiopathic constipation have a range of colonic motor disorders. The majority (80%) had slow transit constipation, dyssynergic defecation, or a combination of slow transit constipation and dyssynergic defecation. In addition, many patients (51%) with chronic idiopathic constipation have a concurrent upper GI tract transit disorder.