Dr. Abrahamowicz is a James McGill Professor at McGill University.
Use of nonbiologic disease-modifying antirheumatic drugs and risk of infection in patients with rheumatoid arthritis
Version of Record online: 30 JUL 2008
Copyright © 2008 by the American College of Rheumatology
Arthritis Care & Research
Volume 59, Issue 8, pages 1074–1081, 15 August 2008
How to Cite
Lacaille, D., Guh, D. P., Abrahamowicz, M., Anis, A. H. and Esdaile, J. M. (2008), Use of nonbiologic disease-modifying antirheumatic drugs and risk of infection in patients with rheumatoid arthritis. Arthritis & Rheumatism, 59: 1074–1081. doi: 10.1002/art.23913
- Issue online: 30 JUL 2008
- Version of Record online: 30 JUL 2008
- Manuscript Accepted: 10 APR 2008
- Manuscript Received: 26 JUL 2007
- Bristol-Myers Squibb
- Canadian Arthritis Network, one of the Federal Networks of Centres of Excellence. Grant Number: 03-MNO-03R
- Investigator Salary award from The Arthritis Society of Canada
Rheumatoid arthritis (RA) is associated with increased frequency of and mortality from infections, which may be related to host factors, RA itself, inflammation, or medication side effects. This study was undertaken to determine the effect of nonbiologic disease-modifying antirheumatic drugs (DMARDs) on infection risk in RA.
We performed a retrospective, longitudinal study of a population-based RA cohort in British Columbia, Canada, followed from January 1996 to March 2003 using administrative data. We evaluated mild infections (requiring a physician visit or antibiotics) and serious infections (requiring or complicating hospitalization). Adjusted risk of mild and serious infections associated with DMARD exposure was estimated using generalized estimating equation extension of multivariate Poisson regression models, after adjusting for baseline covariates (age, sex, RA duration, socioeconomic status) and time-dependent covariates (corticosteroids, comorbidity, prior infections).
A total of 27,710 individuals with RA provided 162,710 person-years of followup. Of these, 25,608 (92%) had at least 1 mild infection and 4,941 (18%) had at least 1 serious infection. Use of DMARDs without corticosteroids was associated with a small decrease in mild infection risk of statistical significance but unclear clinical significance (adjusted rate ratio [RR] 0.90, 95% confidence interval [95% CI] 0.88–0.93 relative to no corticosteroid or DMARD use). Use of DMARDs without corticosteroids was not associated with increased serious infection risk (adjusted RR 0.92, 95% CI 0.85–1.0). Use of corticosteroids increased the risk of mild and serious infections.
Our results indicate that use of nonbiologic DMARDs, including methotrexate, does not increase the risk of infection in RA, whereas use of corticosteroids does. This has important implications for counseling individuals with RA concerning risks and benefits of DMARDs.