Purpose: Aim of this observational case-control study was to assess the prevalence, features, and risk factors of colonic diverticula in patients with ulcerative colitis (UC).
Methods: The data of 896 UC patients aged ≥ 30 years from Brescia IBD database were retrospectively analyzed. Individuals with colonic diverticula were identified and prevalence was compared with that of control patients undergoing screening colonoscopy after gender/age matching. A nested cohort study was then conducted among UC patients in order to define eventual association of diverticula with specific clinico-pathologic parameters.
Results: Prevalence of subjects with diverticula was 11.4% among 465 UC patients aged 49 years and older, significantly lower than 35.1% prevalence in control patients of same age and gender (p < 0.001). Advancing age was a significant risk factor for diverticula development in both groups. Among UC patients, a short duration and a late onset of UC were both significantly associated to the presence of diverticula. Moreover, UC patients with diverticula had a significantly lower frequency of flares per year, even if maximal flare severity and frequency of hospital admission were similar to those of subjects without diverticula. UC patients with diverticula had a trend toward more frequent extension of UC to the left colon, possibly because of their older age. The majority of those patients had few sigmoid diverticula without symptoms.
Conclusions: Development of colonic diverticula is substantially reduced in patients with UC, markedly among those with an early onset, a long history of inflammatory disease, and a high flare frequency. This study reinforces the hypothesis sustaining a protective role of UC against colonic diverticula.
Keywords: Colonic diverticula; Diverticular disease; Natural history of ulcerative colitis; Ulcerative colitis.