Increased Incidence and Impact of Upper and Lower Gastrointestinal Events in Patients with Rheumatoid Arthritis in Olmsted County, Minnesota: A Longitudinal Population-based Study

Abstract

Objective.To assess the incidence and mortality impact of upper and lower gastrointestinal (GI) events in rheumatoid arthritis (RA) compared to non-RA subjects.Methods.We identified incident upper and lower GI events and estimated their incidence rates using person-year methods in a population-based incident RA cohort of residents of Olmsted County, Minnesota, USA (1987 American College of Rheumatology criteria first fulfilled between January 1, 1980, and January 1, 2008) and non-RA subjects from the same population.Results.The study included 813 patients with RA and 813 non-RA subjects (mean followup 10.3 and 10.8 yrs, respectively); 68% women; mean age 55.9 yrs in both cohorts. The rate of upper GI events/100 person-years was 2.9 in RA versus 1.7 in the non-RA cohort (rate ratio 1.7, 95% CI 1.4, 2.2); for lower GI events, the rates were 2.1 in RA versus 1.4 in the non-RA cohort (rate ratio 1.5, 95% CI 1.1, 1.9). The incidence of upper GI bleed, perforation, ulcer, obstruction, and any upper GI event in RA declined over calendar time; the incidence of lower GI events remained unchanged. Exposure to glucocorticoids, prior upper GI disease, abdominal surgery, and smoking were associated with lower GI events in RA. Both upper and lower GI events were associated with increased mortality risk in RA.Conclusion.There is increased risk of serious upper and lower GI events in RA compared to non-RA subjects, and increased GI-related mortality in RA. Prominent declines in incidence of upper, but not lower GI events in RA highlight the need for studies investigating lower GI disease in patients with RA.