To estimate the incidence and risk factors for gastrointestinal (GI) perforation among patients with rheumatoid arthritis (RA).
Claims from employer health insurance plans were used to identify RA patients and those hospitalized for upper or lower GI perforation. GI perforation cases were identified using both a sensitive and specific definition. A Cox model using fixed and time-varying covariates was used to evaluate risk of GI perforation.
Among 143,433 RA patients, and using a maximally sensitive GI perforation definition, 696 hospitalizations with perforation were identified. The rate of perforation was 1.70 per 1000 person years (PYs) [95% CI, 1.58–1.83] and most perforations (83%) occurred in the lower GI tract. The rate of perforation was lower when a more specific GI perforation definition was used (0.87, 95% CI, 0.78–0.96 per 1,000 PYs). Age and diverticulitis were among the strongest risk factors for perforation (diverticulitis hazard ratio=14.5 [95% CI, 11.8–17.7] for more sensitive definition, hazard ratio=3.9 [95% CI, 2.5–5.9] for more specific definition). Among various RA medication groups, and compared to methotrexate, the risk of GI perforation was highest among patients with exposure to concomitant non-biologic disease-modifying antirheumatic drugs and glucocorticoids. Biologics without glucocorticoid exposure was not a risk factor for perforation.
GI perforation is a rare but serious condition that affects patients with RA, most frequently in the lower GI tract. Clinicians should be aware of risk factors for GI perforation when managing RA patients, including age, history of diverticulitis, and use of glucocorticoids or NSAIDs.