Abstract
Abstract
Background
Histologic remission appears to be associated with positive outcomes in ulcerative colitis (UC) patients. However, it is not clear whether UC patients in endoscopic remission have additional benefit from achieving histologic remission. The objective of the study was to assess the relationship between time to relapse and histological activity among UC patients who are in endoscopic remission.
Methods
This was a retrospective observational study conducted at McMaster University Medical Centre in Hamilton, ON, Canada and University of Chicago Hospital, Chicago, IL. UC patients from an ongoing observational database who had achieved endoscopic remission (Mayo score 0) were included. Index colonoscopy was the first colonoscopy where Mayo 0 was achieved. These patients were classified based on their histologic activity: normal (no architectural changes or evidence of UC), inactive colitis (architectural changes but absence of acute inflammation), or active colitis (neutrophils in epithelium, crypt destruction, and/or erosions/ulcers). The primary outcome was time to relapse (defined as symptomatic flare with escalation of medical therapy, UC-related hospitalisation, colectomy, or development of colorectal cancer/dysplasia). Secondary outcomes included reasons for relapse and the association between other baseline variables and risk of relapse. A Cox proportional hazards model was used to evaluate the association of baseline factors with the outcome of relapse.
Results
269 patients with UC and endoscopic remission were included in this study. According to a Kaplan–Meier survival curve analysis, there was no significant difference based on histologic activity with regards to time to relapse (log-rank p = 0.96)(See Figure). Patients with active colitis on histology did not have a higher relapse rate compared with those with inactive colitis (hazard ratio 1.11, p = 0.77), after adjustment for covariates. Older age, 5-aminosalicylate use, and disease location (both left-sided and pan-colitis) were found to be significantly associated with a lower rate of relapse. Symptomatic flare with an escalation of medical therapy accounted for the majority of relapses (80.4%).
Conclusion
Histologic remission did not impact time to relapse in UC patients who had achieved endoscopic remission. This suggests against targeting histologic remission in patients who have achieved endoscopic remission.