FOLLOW UP COLONOSCOPY AFTER ADENOMA RESECTION IN PATIENTS WITH DIVERTICULOSIS OF COLON

Aims To compare the prevalence of colonic polyps, in recurrent colonoscopies, in patients with and without diverticulosis.

Methods A retrospective cohort study. All colonoscopies preformed in our department, between 2007–2015 were reviewed. Patients with, at list, two consecutive colonoscopies, were included. Patients with IBD or prior colonic surgery were excluded.

Patient´s demographics, complete medical history and full endoscopic data was documented.

Results A total of 595 patients met the inclusion criteria. 398 in the diverticulosis group (DG) and 197 patients in the non-diverticulosis group (NDG), mean age 67.8 ± 8.7 vs 64.7 ± 10.5 years, respectively (p < 0.0001). 68% of DG were male, 49% in the NDG (p = 0.029). In the NDG, larger polyps were found in the first and second endoscopy (13 ± 12.7 mm vs 9.7 ± 9.2 mm in first colonoscopy, p = 0.002 and 10.4 ± 16.9 mm vs 7.6 ± 7 mm in the second, p = 0.04), with more advanced histology compared to DG (21.8% vs 11.7% respectively, p = 0.003). Multi variate analysis found the absence of diverticular disease, to be the only significant predicting factor for the presence of advanced adenoma. In the second and third colonoscopies the NDG had a higher rate of adenomatous polyps, compared to DG (78.2%, 65.6% respectively, p = 0.043 in the second colonoscopy, 80.1%, 66% respectively, p = 0.041 in the third colonoscopy). No significant difference was found in the time interval between colonoscopies between the two groups.

Conclusions In a prolonged follow up, we found that the presence of diverticulosis may be a protecting factor against the development of large polyps and advanced histology. Our results suggest that the presence of diverticulosis should not change the follow-up interval recommended. The pathophysiology of this protective effect should be further investigated.