Inflammation, Statin Therapy, and Risk of Stroke After an Acute Coronary Syndrome in the MIRACL Study

Abstract

Patients with acute coronary syndromes have an increased risk of stroke. We measured markers of inflammation in the MIRACL study, a randomized trial of atorvastatin versus placebo in acute coronary syndromes, to assess the relationship of inflammation to stroke. Baseline C-reactive protein (CRP), serum amyloid A (SAA), and interleukin-6 (IL-6) were collected in 2926 (95%) subjects. Baseline markers were related to stroke risk over the 16 weeks of the study. Subjects who subsequently experienced a stroke had higher CRP (27.5 versus 10.2 mg/L, P=0.0032), SAA (30.5 versus 16.0 mg/L, P=0.031), IL-6 (11 231 versus 6841 pg/L, P=0.004), and troponin (6.03 versus 3.19 ng/mL P=0.0032). The risk of stroke was related to greater CRP, SAA, and IL-6 in the placebo group only. Similarly, there was a graded increase in risk of stroke across quartiles of inflammatory markers in the placebo patients only. In acute coronary syndromes, the early risk of stroke relates to both heightened inflammation and size of myocardial necrosis. Treatment with atorvastatin abrogated the risk associated with elevated markers of inflammation in this study, a finding that provides a novel rationale for the use of statins in acute coronary syndromes.