Colonic stasis and chronic constipation: Demystifying proposed risk factors for colon polyp formation in a spinal cord injury veteran population

Abstract

Background and Aims: Patients with spinal cord injury (SCI) suffer significant morbidity from neurogenic bowel. Chronic constipation has long-been a proposed risk factor for polyp development. We performed a retrospective cohort study in veterans with SCI to assess polyp presence in the setting of colonic stasis. Methods: All consecutive patients at the James A. Haley Veterans Affairs Hospital with SCI and neurogenic bowel who completed screening colonoscopy between January 1, 2004 to June 30, 2013 were included. Colonoscopies were excluded if they were aborted, not completed to the cecum, of less than adequate preparation, or if polypectomy was precluded. Patient data included level, duration, and completeness of SCI. Polyp data included number, location, and histology. Results: 325 patients ultimately met inclusion criteria. Most were male (96%). The average age at screening colonoscopy was 62.8 years. The majority of patients had injury to the cervical spine (41.5%). Colon polyps were detected in 130 patients (40%). Adenomatous change was seen in 95 (73%) of these patients. The adenoma detection rate (ADR) across all patients was 29.2%. Polyp presence and ADR demonstrated no statistically significant correlation with level, degree, or duration of SCI. Only patient age at time of screening colonoscopy had a significant correlation with polyp and adenoma presence (P<0.05). Conclusions: SCI had no statistically significant correlation with polyp or adenoma presence. The ADR in our veteran SCI population with chronic constipation is comparable with that reported in the general population.