Lipoprotein-associated phospholipase A2 and coronary calcification. The Rotterdam Coronary Calcification Study
Objectives: Although several studies have recently suggested that lipoprotein-associated phospholipase A2 (Lp-PLA2) is an independent predictor of coronary events, only one study has examined the association between Lp-PLA2 and coronary calcification, using young adults. We investigated the association between Lp-PLA2 activity and coronary calcification assessed by electron-beam computed tomography (EBT) in a population of older participants. Methods and results: The Rotterdam Coronary Calcification Study is a population-based study in men and women aged ≥55 years. Coronary calcification assessed by EBT was quantified in a calcium score according to Agatston's method. Lp-PLA2 activity measured in samples collected 7 years before scanning (n = 520) was associated with coronary calcification in men after adjustment for age. The odds ratio per standard deviation of Lp-PLA2 activity of having a total calcium score >1000 was 1.6 (95% confidence interval: 1.1-2.4), as compared to a total calcium score ≤100. After adjustment for non-HDL and HDL-cholesterol, this association disappeared. In women, the association was less consistent. For Lp-PLA2 measured concurrently to scanning (n = 703), no association was found with coronary calcification. Conclusions: Lp-PLA2 activity is moderately associated with coronary calcification after adjustment for age. The effect of Lp-PLA2 on coronary calcification may be exerted through its effect on LDL-cholesterol.