Background: Recent studies showed that lipoprotein(a) [Lp(a)] is a causal risk factor for cardiovascular disease (CVD). However, whether Lp(a) modifies clinical risk assessment was not established.
Objectives: This study was conducted to determine whether Lp(a) improves CVD risk prediction.
Methods: In 1995, Lp(a) was measured in 826 men and women (age range, 45 to 84 years) from the general community. Incidence of CVD was recorded over 15 years of follow-up.
Results: In models adjusted for Framingham Risk Score (FRS) and Reynolds Risk Score (RRS) variables, the hazard ratio (HR) for incident CVD was 1.37 per 1-SD higher Lp(a) level (SD = 32 mg/dl) and 2.37 when comparing the top fifth quintile with other quintiles. The addition of Lp(a) to the RRS increased the C-index by 0.016. Of the 502 subjects who remained free of CVD, 82 were correctly reclassified to a lower risk category and 49 were reclassified to a higher risk category (predicted 15-year categories: <7.5%, 7.5% to <15%, 15% to <30%, ≥30%) (p < 0.001). Of the 148 subjects who developed CVD, 18 were correctly reclassified to a higher risk category and 17 were reclassified to a lower risk category. In subjects at intermediate risk (15% to <30%), the net reclassification improvement afforded by Lp(a) was 22.5% for noncases, 17.1% for cases, and 39.6% overall. Allele-specific Lp(a) levels did not add to the predictive ability of the FRS or RRS or to Lp(a).
Conclusions: Elevated Lp(a) predicts 15-year CVD outcomes and improves CVD risk prediction. These findings suggest that Lp(a) levels may be used in risk assessment of subjects in the general community, particularly in intermediate-risk groups.
Keywords: atherosclerosis; autoantibodies; lipoproteins; oxidation; oxidation-specific epitopes; oxidized phospholipids.
Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.