Time Trends, Clinical Characteristics, and Risk Factors of Chronic Anal Fissure Among a National Cohort of Patients with Inflammatory Bowel Disease.

BACKGROUND: Chronic anal fissure (CAF) is a common problem that causes significant morbidity. Little is known about the risk factors of CAF among patients with inflammatory bowel disease (IBD).

AIM: To study the clinical characteristics and prevalence of CAF among a cohort of IBD patients.

METHODS: We performed a population-based study on IBD patients from the National Veterans Affairs administrative datasets from 1998 to 2011. IBD and AF were identified by ICD-9 diagnosis codes.

RESULTS: We identified 60,376 patients with IBD between the ages of 18-90 years, 94% males, 59% diagnosed with ulcerative colitis (UC), and 88% were Caucasians. The overall prevalence of CAF was 4% for both males and females. African Americans (AA) were two times more likely to have CAF compared to Caucasians (8 vs. 4%; OR 2.0, 95% CI 1.6-20.2, p = 0.0001) or Hispanics (8 vs. 4.8%; OR 2.1, 95% CI 1.4-25.2, p = 0.0001). The prevalence of CAF significantly dropped with age from 7% at age group 20-50 to 1.5% at 60-90 (p = 0.0001). CD patients were two times more likely to have CAF than UC patients (6 vs. 3%; OR 1.9, 95% CI 1.5-18.2, p = 0.0001). The initial diagnosis of CAF occurred within 14 years after the initial diagnosis of IBD in 74.5% patients.

CONCLUSIONS: CAF is more prevalent among IBD than what is reported in the general population and diagnosed after the diagnosis of IBD. CAF is more prevalent among patients with CD, younger patients, and AA. The current results lay the groundwork for further outcome studies relate to anal fissure such as utilization, hospitalization, and cost.