Impact and risk factors of non-adherence to 5-aminosalicylates in quiescent ulcerative colitis evaluated by an electronic management system

Background and objectiveTo determine the impact of non-adherence to 5-Aminosalicylates (5-ASA) on the risk of flares and to identify risk factors of non-adherence.MethodsObservational, cohort study of ulcerative colitis (UC) patients in clinical remission at least 6months on 5-ASA monotherapy maintenance prescribed by an electronic management program. Adherence was considered when 80% of the prescribed 5-ASA had been dispensed at the pharmacy. The study analyzed the existence and degree of 5-ASA adherence, disease course, UC phenotypic expression, and 5-ASA dose and regimen, and consumption of non-UC chronic drugs during 2-year follow-up.ResultsThe study included 274 patients, 49% males with a median age of 38 (27-49) years old. Overall, 41% of patients were non-adherent to 5-ASA. Risk of flares was reduced in the adherent group (36% vs 54%; OR=0,484; p=0,004), mainly the mild ones (26% vs 38%; OR=0,559; p=0,031). Non-adherence was associated with younger age at diagnosis (32 (26-45) vs 41.5 (21-50), p=0.000) and no-consumption of other chronic treatments (1.1 vs 2.1; OR=1709; p=0,048).ConclusionNon-adherence to 5-ASA evaluated by the pharmaceutical management system was at 41% with a higher risk of relapse. Younger patients and patients who do not receive non-UC chronic treatments showed lower adherence rate.