Characterization of Inflammatory Bowel Disease in the Elderly According to Age of Onset

<b>Background/Objectives</b>: Elderly populations are under-represented in inflammatory bowel disease (IBD) clinical trials, with limited data on phenotype, treatment patterns, outcomes, and comorbidities. The main objective of this study was to evaluate, in an elderly cohort with IBD, demographic and disease characteristics, comorbidity, polypharmacy, and treatment patterns according to the development of IBD at or before old age. Secondarily, the same analysis was performed based on the type of IBD: ulcerative colitis (UC) or Crohn's disease (CD). <b>Materials and Methods</b>: Observational, single-center, retrospective study including patients diagnosed with IBD and aged 65 years or older seen at the IBD office of the Regional University Hospital of Malaga between September and November 2022. Data were recorded on demographic, disease-related, and IBD treatment-related variables, comorbidities, and polypharmacy. A descriptive and analytical study was undertaken according to the age of IBD onset and type of IBD. <b>Results</b>: Of the patients included, 50.8% were male, 55.1% had CD, and 44.9% UC. IBD onset was before age 65 years in 69.5% and ≥65 years in 30.5%. Elderly with IBD who debuted <65 presented longer disease duration (19.67 ± 9.82 years) and required more IBD-related surgeries (37.8%); elderly with IBD who debuted ≥65 were older (77.69 ± 6.26 years), with no differences in the other variables. According to the type of IBD, elderly UC patients were older (74.55 ± 6.9 years), used more aminosalicylates (77.4%), and had higher rates of polypharmacy (90.6%). Elderly patients with CD had higher IBD activity (moderate/severe in 72.3%), used more biologic drugs (58.5%), and required more IBD-related surgeries (44.6%). <b>Conclusions</b>: Elderly patients who develop IBD before or after the age of 65 years are overall very similar in baseline and disease-related characteristics. Elderly with CD have higher IBD activity and require more biologic drugs and IBD-related surgeries. Elderly with UC are older and have higher rates of polypharmacy and aminosalicylate use.