IL-8 Plasma Concentrations and the Risk of Future Coronary Artery Disease in Apparently Healthy Men and Women

OBJECTIVE: To study the role of IL-8 in predicting future coronary artery disease (CAD) in apparently healthy men and women. METHODS AND RESULTS: A nested case-control study was performed in the prospective EPIC-Norfolk population study. We measured baseline IL-8 concentrations among 785 apparently healthy individuals in whom fatal or nonfatal CAD developed during follow-up and 1570 matched controls. Baseline IL-8 concentrations were higher in cases than in matched controls (3.5 pg/mL versus 3.1 pg/mL, P=0.001). The risk of future CAD increased with increasing quartiles of IL-8 (P linearity <0.0001). Among individuals in the highest IL-8 quartile, the unadjusted odds ratio for future CAD was 1.72 (95% CI, 1.34 to 2.21; P<0.0001). The odds ratio for future CAD was still significant after adjustment for traditional risk factors (OR, 1.58; 95%CI, 1.19 to 2.09; P=0.002) and after additional adjustment for C-reactive protein and white cell count (OR, 1.77; 95% CI, 1.21 to 2.60; P=0.001). CONCLUSIONS: We conclude that among apparently healthy men and women, elevated levels of IL-8 are associated with an increased risk of future CAD. These prospective data support a role for IL-8 in the development of CAD events.