Soluble CD40L and Cardiovascular Risk in Women

BACKGROUND: The immune-signaling dyad CD40/CD40L promotes atherogenesis, and patients with unstable angina have elevated plasma levels of soluble CD40L (sCD40L) and membrane-bound CD40L. It is unknown, however, whether elevations of circulating sCD40L precede the onset of acute cardiovascular symptoms. METHODS AND RESULTS: In a prospective, nested case-control evaluation of healthy middle-aged women, mean concentrations of sCD40L at baseline were significantly higher among 130 participants who subsequently developed myocardial infarction, stroke, or cardiovascular death (cases), compared with 130 age- and smoking-matched women who remained free of cardiovascular disease (controls) during a 4-year follow-up (2.86 ng/mL for cases versus 2.09 ng/mL for controls; P=0.02). Women with concentrations above the 95th percentile of the control distribution (>3.71 ng/mL) had a significantly increased relative risk (RR) of developing future cardiovascular events (RR, 3.3; 95% CI, 1.2 to 8.6; P=0.01) that remained after adjustment for usual cardiovascular risk factors (multivariate RR, 2.8; 95% CI, 0.9 to 8.0; P=0.05). CONCLUSIONS: High plasma concentrations of sCD40L may be associated with increased vascular risk in apparently healthy women.