Lipoprotein-associated phospholipase A2 and carotid intima-media thickness in individuals classified as low-risk according to Framingham.

BACKGROUND: The Framingham risk score (FRS) has long been used as a global tool to estimate coronary heart disease (CHD) risk, but data has shown that subclinical CHD may exist in those classified as low risk by FRS, and as a result, there is potential for misclassification. Lipoprotein-associated phospholipase A2 (Lp-PLA2) and carotid intima-media thickness (CIMT) are two emerging risk markers that are predictive of future CHD events. PURPOSE: To examine Lp-PLA2 and CIMT values in low risk individuals, and to explore the relationship between Lp-PLA2 and CIMT. METHODS: A total of 229 men and women (age =53±7 years) underwent body composition analysis, objective physical activity measurement, fasting blood draw to determine standard lipid values and Lp-PLA2 mass, and CIMT measurement through ultrasound. RESULTS: For all subjects, mean CIMT was 0.61±0.1 mm, mean Lp-PLA2 mass was 197±45 ng/dL. A total of 19.5% and 34.6% of women and 4.6% and 73.8% of men were considered at elevated risk for CHD by CIMT (>75(th) percentile for age) and Lp-PLA2 mass (>200 ng/dL) standards, respectively. Both CIMT and Lp-PLA2 mass were significant independent predictors of each other, whereas traditional risk markers (lipids, glucose) were not. CONCLUSIONS: Results suggest that in those classified as low risk by FRS, evidence of increased CHD risk may exist through the use of newer risk markers like CIMT and Lp-PLA2. These emerging markers may aid in the earlier detection and intervention of subclinical CHD.