Cumulative risk of perianal Crohn’s disease in population-based cohorts: a systematic review and meta-analysis of twenty-year follow-up

Crohn’s disease (CD) is an immunologically mediated inflammatory condition affecting the gastrointestinal tract, with pathology involving the entire thickness of the bowel wall. Herein, we reported the cumulative risk of perianal CD (pCD) in population-cased cohorts in a systematic review and meta-analysis of a twenty-year follow-up. A thorough investigation was carried out using the Cochrane Library, PubMed, Scopus, Web of Science, and CNKI databases up to November 14, 2024, with restrictions to study design. The Comprehensive Meta-Analysis version 3.0 software was used to compute the event rate/cumulative risk and 95% confidence interval (CI). A total of 2741 records were identified through the database and other sources, and ultimately, 22 articles were included in the meta-analysis. The overall cumulative risk of pCD was 20.1% (95%CI: 15.2%, 26%) with I 2 = 99.5%. The 1-year cumulative risk of pCD after diagnosis was 10.8% (95%CI: 6.9%, 16.6%), 3-year was 13.5% (95%CI: 8.6%, 20.5%), 5-year was 16% (95%CI: 10.9%, 22.9%), 10-year was 18.5% (95%CI: 15.4%, 22%), 15-year was 22.3% (95%CI: 16.3%, 29.8%), and 20-year was 26.2% (95%CI: 16.3%, 39.3%). The cumulative risk of pCD analysis found that 20.1% of CD patients had pCD. The risk of developing perianal disease increased over time, with higher rates at 1, 3, 5, 10, 15, and 20 years. The cumulative risk varied by continent, with Asia having the highest rate at 25.9% and Europe the lowest at 16.8%.