EPIDEMIOLOGICAL AND CLINICAL PROFILE OF CROHN'S DISEASE IN A BRAZILIAN REFERRAL CENTER IN 30 YEARS OF FOLLOW-UP.

Background: Crohn's disease (CD) is a chronic inflammatory disease, with a heterogeneous clinical course, which can affect any segment of the gastrointestinal tract. Data on the natural history of CD in developing countries are rare.

Objective: to delineate the clinical, epidemiological, and longitudinal characteristics of CD patients at a Brazilian referral center.

Methods: this is an observational, cohort, retrospective study, carried out from the collection of data obtained from the medical records of individuals diagnosed with CD followed up in the period between 1991 and 2021.

Results: A total of 328 participants were included, 54.3% female. The median age at diagnosis was 31 years [interquartile range (IQR)=14-45]. At diagnosis, there was a predominance of the stricturing form (38.7%) and ileocolonic location (53.7%). Among the patients with the inflammatory form, 10.8% evolved to the stricturing or penetrating forms, and the time they remained with uncomplicated disease had a median of 6 years (IQR=0-13). Aminosalicylates were used in 70.7% of the patients, but there has been a reduction in their use in the last 15 years (P=0.04). Corticosteroids were used in 90.2% of the participants, with a median time of use of 12 months (IQR=0-36). Immunosuppressants were used in 93.9% of participants. Two hundred and ten patients (64%) received treatment with immunobiological. The median interval between diagnosis and initiation of biological therapy was 24 months (IQR=12-60). One hundred and eighty-nine patients (57.6%) were hospitalized during follow-up, and the median hospital stay was 20 days (IQR=11-36). In the last 15 years, there was a decrease in the hospitalization rate (P<0.001), but there was no change in the number of hospitalizations per patient (P=0.62). One hundred and fifty-two patients (46.3%) underwent surgical treatment during the period evaluated and the most frequently performed surgeries were enterectomies (26.8%) and perianal procedures (25%). In the last 15 years, there has been a decrease in the rate of surgeries (P=0.04) and in the number of surgeries per patient (P<0.001).

Conclusion: The data presented indicate a high prevalence of complicated CD at the onset of follow-up, alongside a significant percentage of corticosteroid use and hospitalization. However, over the past 15 years, there has been a notable reduction in hospitalization rates, surgical rates, and the number of surgeries per patient.