Intestinal complications in Brazilian patients with ulcerative colitis treated with conventional therapy between 2011 and 2020

This was an observational, descriptive, and retrospective study from 2011 to 2020 from the Department of Informatics of the Brazilian Healthcare System database.To describe the intestinal complications (IC) of patients with ulcerative colitis (UC) who started conventional therapies in Brazil´s public Healthcare system.Patients ≥ 18 years of age who had at least one claim related to UC 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) code and at least 2 claims for conventional therapies were included. IC was defined as at least one claim of: UC-related hospitalization, procedures code for rectum or intestinal surgeries, and/or associated disease defined by ICD-10 codes (malignant neoplasia of colon, stenosis, hemorrhage, ulcer and other rectum or anus disease, megacolon, functional diarrhea volvulus, intussusception and erythema nodosum). Descriptive statistics, annual incidence, and incidence rate (IR) [per 100 patient-years (PY)] over the available follow-up period were cal-culated.In total, 41229 UC patients were included (median age, 48 years; 65% women) and the median (interquartile range) follow-up period was 3.3 (1.8-5.3) years. Conventional therapy used during follow-up period included: mesalazine (87%), sulfasalazine (15%), azathioprine (16%) or methotrexate (1%) with a median duration of 1.9 (0.8-4.0) years. Overall IR of IC was 3.2 cases per 100 PY. Among the IC claims, 54% were related to associated diseases, 20% to procedures and 26% to hospitalizations. The overall annual incidence of IC was 2.9%, 2.6% and 2.5% in the first, second and third year after the first claim for therapy (index date), respectively. Over the first 3 years, the annual IR of UC-related hospitalizations ranged from 0.8% to 1.1%; associated diseases from 0.9% to 1.2% - in which anus or rectum disease, and malignant neoplasia of colon were the most frequently reported; and procedure events from 0.6% to 0.7%, being intestinal resection and polyp removal the most frequent ones.Study shows that UC patients under conventional therapy seem to present progression of disease developing some IC, which may have a negative impact on patients and the burden on the health system.