Rectal evacuation disorders tied to poor bowel preparation in chronic constipation patients

Outlet dysfunction is associated with suboptimal bowel preparation and decreased cecal intubation, among others, in patients with chronic constipation undergoing colonoscopy, reveals a study.

A total of 274 patients with chronic constipation who underwent anorectal manometry and at least one colonoscopy at two tertiary referral centres from 2003 to 2019 were included in this analysis. The authors also identified a subgroup of patients who underwent colonic transit testing through radiopaque marker testing.

Using univariate and multivariate analyses, the authors determined the demographic, medical, and constipation-related factors contributing to poor bowel preparation and their effect on standardized quality metrics.

Suboptimal bowel preparation correlated with both outlet dysfunction (prolonged balloon expulsion) and slow-transit constipation. In addition, outlet dysfunction correlated with reduced cecal intubation rates, adenoma detection rates, and sessile serrated polyp detection rates.

Multivariate analyses controlling for demographic and known factors associated with poor bowel preparation revealed the association of outlet dysfunction with a nearly threefold likelihood of suboptimal bowel preparation (odds ratio [OR], 2.9, 95 percent confidence interval [CI], 1.6‒5.1) and a threefold decrease in cecal intubation rates (OR, 0.3, 95 percent CI, 0.1‒0.8).

In a subgroup of patients with radiopaque marker colonic transit testing available, slow-transit constipation correlated with a twofold likelihood of suboptimal bowel preparation (OR, 2.2, 95 percent CI, 1.1‒4.4).

“Constipated patients with a rectal evacuation disorder may represent a subgroup of patients that could benefit from individualized strategies for better bowel preparation,” the authors said.