Prognosis of Patients with Ulcerative Colitis in Sustained Remission After Thiopurines Withdrawal.

BACKGROUND: The ideal length of treatment with thiopurines in patients with ulcerative colitis (UC) in sustained remission remains unknown. It is widely accepted that the drug withdrawal is associated with a worse outcome. The aim of this study was to analyze the outcome after this withdrawal and to identify predictors of relapse. METHODS: A multicenter and retrospective study was designed. A total of 102 patients with UC who discontinued thiopurines in a situation of sustained remission were included. All the patients were followed up until last revision or until relapse (understood as the occurrence of signs and symptoms of UC that required a rescue treatment). RESULTS: After thiopurines withdrawal, overall relapse was recorded in 32.35% of the patients: 18.88% in the first year, 36.48% in the third, and 43.04% in the fifth year after withdrawal. On multivariate analysis, predictors of relapse were the time from diagnosis of UC until the starting of thiopurines (hazard ratio [HR], 1.01; 95% confidence interval [CI], 1.01-1.02; P = 0.039), the number of relapses before the withdrawal (HR, 1.3; 95% CI, 1.01-1.66; P = 0.029), pancolitis (HR, 5.01; 95% CI, 1.95-26.43; P = 0.028), the duration of treatment with thiopurines (HR, 0.15; 95% CI, 0.03-0.66; P = 0.013) and the situation of biological remission at withdrawal (HR, 0.004; 95% CI, 0.0001-0.14; P = 0.002). CONCLUSIONS: The withdrawal of thiopurines in patients with UC, although in sustained remission, is related to a high relapse rate. Clinical variables such as the extent of the disease, the duration of treatment or time from diagnosis to the start of thiopurines should be considered before stopping these drugs.