S1813 Prognostic Significance of Anti-Integrin-αvβ6 Autoantibody Expression for Adverse Clinical Outcomes in Ulcerative Colitis: A Systematic Review and Meta-Analysis

Introduction: Ulcerative colitis (UC) is a chronic inflammatory bowel disease marked by periods of remission and relapse. Reliable biomarkers that predict disease severity, progression, and therapeutic response are crucial for guiding management. Recently, IgG autoantibodies against the epithelial-restricted integrin αvβ6 have been explored as diagnostic biomarkers in UC; however, their prognostic utility remains unclear. This systematic review and meta-analysis aimed to evaluate the prognostic value of anti-integrin αvβ6 autoantibodies in UC-related adverse outcomes. Methods: A systematic search of PubMed and Google Scholar through May 2025, augmented by snowballing, was conducted to identify studies evaluating the link between anti-integrin αvβ6 autoantibodies and UC-related adverse outcomes. These outcomes were defined as the development of pouchitis, escalation of therapy, or non-responsiveness to 2 or more advanced treatments (biologics or Janus kinase inhibitors). Discriminative power of anti-integrin αvβ6 autoantibodies was assessed using pooled area under the curve (AUC) values calculated via a binary random-effects model. Heterogeneity was evaluated using the I² statistic, and leave-one-out sensitivity analysis was performed to assess reliability. Results: Four studies comprising a total of 1,194 patients were included. Pooled AUC for anti-integrin αvβ6 autoantibodies was 0.78 (95% CI: 0.70–0.86; P < 0.01), indicating good discriminatory performance as a prognostic biomarker for UC-related adverse outcomes, with a 78% probability of correctly classifying patient outcomes. Moderate heterogeneity was observed (I² = 56.51%), reflecting variability across studies, likely due to differences in population characteristics or endpoint definitions. Sensitivity analysis confirmed the robustness of the findings, as exclusion of any single study yielded consistent AUC values (0.77–0.79), with all 95% confidence intervals excluding the null value. Conclusion: Anti-integrin αvβ6 autoantibodies exhibit clinically meaningful prognostic performance for adverse outcomes in UC, enabling the identification of high-risk patients who may benefit from early intervention. Despite methodological heterogeneity across studies, the results remained statistically valid. Further analysis in large, prospective multicenter studies is needed to establish standardized protocols for measuring anti-integrin αvβ6 autoantibodies and to confirm their role in personalizing therapy and improving clinical outcomes in UC patients.