Dr. Bobba has received consulting fees, speaking fees, and/or honoraria from Abbott, Bristol-Myers Squibb, Schering-Plough, and UCB (less than $10,000 each).
Systemic Lupus Erythematosus
The protective effect of antimalarial drugs on thrombovascular events in systemic lupus erythematosus
Version of Record online: 7 JAN 2010
Copyright © 2010 by the American College of Rheumatology
Arthritis & Rheumatism
Volume 62, Issue 3, pages 863–868, March 2010
How to Cite
Jung, H., Bobba, R., Su, J., Shariati-Sarabi, Z., Gladman, D. D., Urowitz, M., Lou, W. and Fortin, P. R. (2010), The protective effect of antimalarial drugs on thrombovascular events in systemic lupus erythematosus. Arthritis & Rheumatism, 62: 863–868. doi: 10.1002/art.27289
- Issue online: 25 FEB 2010
- Version of Record online: 7 JAN 2010
- Accepted manuscript online: 7 JAN 2010 12:00AM EST
- Manuscript Accepted: 25 NOV 2009
- Manuscript Received: 5 JUN 2009
- Arthritis Society. Grant Number: 97/0007
- Canadian Institutes of Health Research. Grant Numbers: MOP-49509, MOP-64336
- Arthritis Centre of Excellence, University of Toronto
- The Canadian Network for Improved Outcomes in Systemic Lupus is supported in part by Lupus Canada
- Lupus Ontario
- Lupus Foundation of Ontario
- BC Lupus
- Arthritis and Autoimmune Research Centre Foundation
- The Centre for Prognostic Studies in Rheumatic Disease–University of Toronto Lupus Clinic is supported in part by the Smythe Foundation
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The antimalarial medication hydroxychloroquine has been proposed as a thromboprotective agent in systemic lupus erythematosus (SLE), but studies thus far have been limited by the possibility of confounding by indication. This study was conducted to assess whether exposure to antimalarial drugs is associated with a decrease in thrombovascular events (TEs) in patients with SLE.
The study was designed as a nested case–control study embedded in an inception cohort of patients with SLE, which allowed adjustments for possible confounding by calendar year, duration of disease, duration of observation, and severity of lupus. After controlling for the possible confounding variables in conditional logistic regression models, the use of antimalarial drugs was assessed for its effects on the development of TEs in lupus patients.
Fifty-four cases of TE were identified, and these were matched with 108 control subjects (lupus patients without TEs). Univariate analyses identified older age (odds ratio [OR] 1.04, 95% confidence interval [95%CI] 1.01–1.07) or being older than age 50 years (OR 3.5, 95% CI 1.4–8.6) and ever having hypertension (OR 2.5, 95% CI 1.0–5.8) as being associated with an increased risk of TEs, whereas use of antimalarial drugs (OR 0.31, 95% CI 0.13–0.71) was associated with a decreased risk of TEs. Separate analyses were done for arterial and venous TEs, which yielded similar results. In multivariate analyses, use of antimalarial drugs (OR 0.32, 95% CI 0.14–0.74) and older age (OR 1.04, 95% CI 1.01–1.07) were the only 2 variables that remained significant.
The results from this nested case–control study demonstrate that, after accounting for the effects of disease severity, disease duration, and calendar year, antimalarial drugs were found to be thromboprotective, being associated with a 68% reduction in the risk of all TEs, with a range of risk reduction of at least 26% up to as high as 86%.