E151 The impact of biologic therapy on uveitis rates in an ankylosing spondylarthritis cohort

Joshy, Neha and Sahu, Viraat (2026) E151 The impact of biologic therapy on uveitis rates in an ankylosing spondylarthritis cohort. Rheumatology, 65 (Supple). ISSN 1462-0324

Abstract

Background/Aims Ankylosing spondylarthritis (axSpA) is a chronic inflammatory condition associated with extra-articular manifestations. Predominantly anterior uveitis (AU) affects up to 47% of patients. Ongoing research supports biologics suppressing AU, but there are limited real-world data, which this study addresses. Aims: Retrospectively investigate AU incidence and prevalence, and to determine biologic treatment impact. Using uveitis rates throughout biologic therapy (pre/post) and comparing to a control group using NSAIDS/DMARDs/nothing. Methods Retrospective data were collected from electronic hospital records of Morecambe Bay Trust’s axSpA population. Specifically, demographics, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), HLA-B27 status, treatment and ophthalmic diagnoses. Incomplete records were excluded as part of the criteria. Prevalence was defined as AU episodes ≥ 1. Incidence was defined as (AU episodes/100 person years [PY]) calculated to June 2025 in (i) AU cases (n = 32), (ii) all patients with >1 PY follow-up (n = 78). Poisson Regression performed for AU predictors. Results Of 125 patients, 101 met the criteria. Mean age of 52 years; 68% male. Biologic group had lower HLA-B27 positivity (23% vs 43%) but higher BASDAI (4.8 vs 3.2). AU had 32.7% prevalence overall, higher in non-biologics than biologics (46.4% vs 27.3%) (p = 0.068). Among AU population, incidence was 14.9/100 PY pre-biologic, 15.3/100 PY post-biologic, and 17.2/100 PY non-biologic. The wider cohort had incidence 7.3/100 PY vs 15.1/100 PY (IRR 0.49) for biologics vs non-biologics.Poisson Regression showed biologics were protective (IRR 0.23, p= 0.002) and higher BASDAI lowered risk (IRR 0.77, p=0.002). AU reduced with age, around 5% per year (IRR 0.95, p = 0.001). Sex and HLA-B27 were insignificant. Conclusion AU prevalence did not differ significantly between groups but trended higher in controls. Biologics were associated with a 50% reduction in AU incidence in the wider cohort, though only 11% in the smaller AU cohort. The apparent 3% increase post-biologics likely reflects surveillance bias and disease progression. Regression confirmed biologics and older age reduced AU risk, while the BASDAI finding probably reflected treatment selection. Data support that biologics reduce AU and emphasise the benefits of early initiation with ophthalmic surveillance. Disclosure N. Joshy: None. V. Sahu: None.