Hospitalization Rates and Utilization Among Patients With Rheumatoid Arthritis: A Population-Based Study From 1987 to 2012 in Olmsted County, Minnesota

Objective: To examine whether all-cause hospitalization rates for patients with rheumatoid arthritis (RA) differ from those for patients without RA. Patients and Methods: This was a retrospective population-based cohort study focused on Olmsted County, Minnesota. The RA cohort consisted of patients 18 years and older who first fulfilled 1987 American College of Rheumatology criteria for RA in the 1980 to 2007 period, and was compared with a cohort of similar age, sex, and calendar year without RA. Data on all hospitalizations were retrieved electronically for the 1987 to 2012 period. Analyses used person-year methods and rate ratios (RRs) comparing patients with and without RA. Results: The 799 patients with RA experienced 2968 hospitalizations, and the 797 patients without RA experienced 2069 hospitalizations. Patients with RA were hospitalized at a greater rate than were patients without RA (RR, 1.51; 95% CI, 1.42-1.59). This increased rate of hospitalization was found in both sexes, all age groups, all calendar years studied, and throughout disease duration. Men with RA were hospitalized for depression at a greater rate than were men without RA (RR, 7.16; 95% CI, 2.78-30.67). Patients with RA were hospitalized at a greater rate for diabetes mellitus than were subjects without RA (RR, 2.45; 95% CI, 1.34-4.89). In patients with RA, the indicators of disease severity (eg, seropositivity, erosions, and nodules) in the first year after RA incidence were associated with higher rates of hospitalization. Conclusion: Patients with RA were hospitalized for all causes at a greater rate than were patients without RA. Increased rates of hospitalization were true for several disease categories and patient subgroups. (C) 2015 Mayo Foundation for Medical Education and Research