Soluble CD40 ligand as a predictor of coronary artery disease and long-term clinical outcomes in stable patients undergoing coronary angiography.

BACKGROUND: In patients with acute coronary syndrome (ACS), elevated levels of soluble CD40 ligand (sCD40L) are associated with increased risk of cardiovascular events. We evaluated sCD40L levels and future cardiovascular events in patients not experiencing ACS. METHODS: Serum sCD40L levels were measured in 909 patients undergoing angiography. A three-way matching scheme (age, gender and catheterization time period) identified 303 patients with coronary artery disease (CAD) who experienced a cardiac event within 1 year (CAD/event), 303 patients with CAD free of events (CAD/no event) and 303 patients without CAD and free of events (no CAD). RESULTS: Average age was 64 +/- 11 years; 74% were males. Median (+/- SE) sCD40L levels were higher for no CAD patients (335 +/- 60 pg/ml) compared to CAD (248 +/- 65 pg/ml, p = 0.01) and to CAD/event (233 +/- 63 pg/ml, p < 0.001). There was no significant difference in median sCD40L levels between CAD/no event and CAD/event patients. Higher sCD40L quartiles were associated with a significant decrease in the risk of CAD/event versus no CAD (quartile 4 versus quartile 1: odds ratio = 0.59, p = 0.03). There was a nonsignificant trend towards a decreased risk of CAD as compared to no CAD, and for CAD/event versus CAD. CONCLUSIONS: In non-ACS patients, higher sCD40L levels were associated with a decreased risk of CAD. This novel interaction of sCD40L raises interesting questions for CAD pathogenesis.