P581 Age-related patterns in biological therapy use and surgery among patients with IBD: Insights from the Belgian PANTHER cohort

Abstract

Abstract Background Inflammatory bowel diseases (IBD) are predominantly diagnosed during the second to third life decade. However, the disease may manifest itself at any age and current understanding of differences in clinical presentation and therapy use among age groups is still limited. We aimed to analyse age-related patterns in biological and surgical treatment among patients with IBD. Methods This study utilized data from the PANTHER cohort, a prospective Belgian inception cohort including 473 adult patients with IBD from 3 Belgian referral centres. Patient inclusion took place from 2015 to 2023. Patients were categorized into groups based on the age at diagnosis: 'young adult-onset' (18-39 years), 'adult-onset' (40-59 years), and ‘elderly-onset’ (³60 years). Baseline characteristics and treatments were analysed using Chi square, Mann-Whitney U tests, log-rank tests and/or Cox regression in SPSS. Results Baseline characteristics are shown in Table 1. No significant differences were found between age groups in terms of IBD diagnosis, gender, median follow-up duration, and smoking status. Use of biologics differed significantly across age groups with highest uptake in young-adult onset patients (65.8%, P<0.001). Significant differences were found in selection of first biologic with vedolizumab as most frequently selected option in the elderly compared to anti-TNF in the youngest age group (P=0.002). Time to initiation of a biological was earlier in the youngest cohort (P=0.002, Figure 1). Cox regression analysis revealed that older age at diagnosis (HR 0.987, 95%CI [0.98;0.996], P=0.006), UC (HR 0.495, 95%CI [0.50;0.39], P<0.001) and centre of follow-up (Brussels vs Leuven: HR 0.663, 95%CI [0.4;1], P=0.048) were associated with a lower risk of biological initiation. When analysing CD separately, independent risk factors associated with biological use were perianal disease (HR 2.26, 95%CI [1.6;3.2], P<0.001), L3 (HR 1.85, 95%CI [1.3;2.6], P<0.001,) and L4 (HR 12.7, 95%CI [1.6;98.7], P=0.015,) location (compared to L1 location). In UC patients, E2 (HR 7.9, 95%CI [2.8;22.4], P<0.001) and E3 (HR 6.9, 95%CI [2.4;19.3], P<0.001) were related to earlier use of biologics. During follow-up, 19% of CD and 5.1% of UC patients required IBD-related surgery. Univariate analysis showed a higher need for surgery in younger patients (P=0.042), however, this difference was no longer significant when analysing CD (P=0.272) and UC (P=0.09) patients as separate groups. Conclusion Analysis of the PANTHER Biobank reveals significant age-related variation in the administration of biological therapies among IBD patients.