Risk Factors for Pouchitis After Ileal Pouch-Anal Anastomosis in Ulcerative Colitis Patients

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the surgical gold standard for patients with ulcerative colitis (UC) who require surgery. However, the most common long-term complication, pouchitis, significantly affects postoperative quality of life and often results in recurrent or chronic inflammation. This study systematically summarizes the risk factors for pouchitis after IPAA in patients with UC over the past 2 decades and discusses reliable risk factors and existing controversies.

A comprehensive literature search was conducted in PubMed, Embase, and Cochrane Library for studies published between January 2006 and December 2025. The search terms included "ulcerative colitis," "ileal pouch-anal anastomosis," "IPAA," "pouchitis," and "risk factors." Two reviewers independently screened the literatüre according to the inclusion and exclusion criteria. Meta-analysis was performed using inverse-variance weighting with fixed- or random effects models depending on the degree of heterogeneity.

A total of 49 eligible citations were included. Based on the literature search, risk factors for pouchitis were classified into 6 categories: clinical, endoscopy related, histological, laboratory, genetic, and other factors. Preoperative steroid use and primary sclerosing cholangitis (PSC) were identified as reliable risk factors based on consistent findings from multivariate analysis. Pooled analyses identified 4 factors with consistent evidence: male sex (pooled odds ratio (OR) = 1.34, 95% CI = 1.00-1.79), PSC (pooled OR = 3.52, 95% CI = 2.53-4.90), preoperative steroid use (pooled OR = 1.89, 95% CI = 1.48-2.41), and preoperative antitumor necrosis factor (anti-TNF) therapy (pooled OR = 1.35, 95% CI = 1.17-1.57). Other factors such as extraintestinal manifestations, preoperative anti-TNF therapy, and short J-pouch length demonstrated significant associations in multiple studies, although the findings were inconsistent. Smoking, age, and sex remain controversial risk factors because of conflicting evidence.

Preoperative steroid use and PSC are the most reliable risk factors for pouchitis after IPAA in patients with UC. Many proposed risk factors require further validation in large-scale prospective studies, and standardized diagnosis criteria and unified research methods are essential for evaluating the role of potential risk factors.