RESUMO
BACKGROUND AND OBJECTIVE: To determine the impact of non-adherence to 5-Aminosalicylates (5-ASA) on the risk of flares and to identify risk factors of non-adherence. METHODS: Observational, cohort study of ulcerative colitis (UC) patients in clinical remission at least 6 months 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. RESULTS: The 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). CONCLUSION: Non-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.