Association of Diverticulitis with Prolonged Spondyloarthritis: An Analysis of the ASAS-COMOSPA International Cohort

This study examined the relationship between spondyloarthritis (SpA) duration and gastrointestinal comorbidities other than inflammatory bowel disease (IBD). We evaluated the association between SpA duration and upper gastrointestinal ulcers, hepatitis B (HBV), hepatitis C (HCV) and diverticulitis using data from a large international cross-sectional study. Binary regression models were created, adjusted for age, sex, body mass index (BMI), smoking, alcohol, non-steroidal anti-inflammatory drugs (NSAIDs), disease-modifying anti-rheumatic drugs (DMARDs), biologics, steroids, IBD history and country. Subgroup analysis was performed by disease phenotype. The data of 3923 participants were analysed. The prevalence of gastrointestinal conditions were 10.7% upper gastrointestinal ulcers; 4.7% viral hepatitis and 1.5% diverticulitis. While SpA duration was not associated with upper gastrointestinal ulcers, HBV or HCV, longer SpA duration was significantly associated with diverticulitis (odds ratios (OR) = 1.18, 95% confidence interval (CI): 1.03⁻1.34), reflecting an 18% increase for every five years of SpA duration. Other significant associations with diverticulitis were age and high alcohol intake but not medication history. In subgroup analyses, the association was strongest with those with axial SpA. The reasons for this association of increased diverticulitis with disease duration in SpA, especially those with axial disease, are unclear but may reflect shared underlying gut inflammation. Diverticulitis should be considered, in addition to IBD, when SpA patients present with lower gastrointestinal symptoms.