The risk of stroke in patients with rheumatoid arthritis (RA) increases as the auto-immune disease worsens, findings from a large case-control study indicate.
"There is evidence that cardiovascular and cerebrovascular diseases are more common in patients with RA than in patients without RA and two studies have demonstrated an increased risk of stroke among patients with RA," say Frederick Wolfe (National Data Bank for Rheumatic Diseases, Wichita, Kansas, USA) and co-authors.
However, understanding of the links between RA and stroke is incomplete, they point out.
"No studies have addressed the effect of RA severity, RA therapy, or cardiovascular risk factors on the risk of stroke in patients with RA," the team writes.
Accordingly, the researchers used information collected longitudinally from 269 stroke patients, including 41 who had RA, and compared data from each of these patients with data from up to 20 control volunteers who had not suffered stroke and who showed no evidence of auto-immune dysfunction.
Writing in the journal Arthritis Care and Research, the authors explain that this comparison showed that the risk for stroke in those with RA was increased 1.64-times, while the risk for ischemic stroke was increased 2.66-fold.
The researchers found various factors that significantly predicted the increased risk of stroke in RA patients including, the use of low-dose aspirin, previous myocardial infarction, and hypertension, with odds ratios of 3.60, 2.58, and 1.98, respectively.
Interestingly, several traditional cardiovascular risk factors such as diabetes, obesity, and smoking had no bearing on stroke risk in RA patients in the study.
While they demonstrated significant links between stroke and RA severity, the authors caution that the number of actual cerebrovascular events in their study was small, reducing the statistical power of their findings.