Apolipoprotein a2 isoforms in relation to the risk of myocardial infarction: A nested case-control analysis in the jphc study

Aim: The fact that low concentrations of high-density lipoprotein cholesterol are associated with the risk of car-diovascular disease is well known, but high-density lipoprotein metabolism has not been fully understood. Apoli-poprotein A2 (ApoA2) is the second-most dominant apolipoprotein of high-density lipoprotein. We tested the hypothesis that ApoA2 isoforms are inversely associated with myocardial infarction. Methods: We measured the plasma levels of three ApoA2 isoforms (ApoA2-ATQ/ATQ, ApoA2-ATQ/AT, ApoA2-AT/AT) in nested case-control study samples of 1:2 from the Japan Public Health-Center-based Study (JPHC Study): 106 myocardial infarction incidence cases and 212 controls. Results: ApoA2-AT/AT was inversely associated with risk of myocardial infarction, in a matched model (OR, 2.78; 95% Cl, 1.26-6.09 for lowest compared with the highest quartile), but its association was attenuated after adjustment for smoking only (OR=2.13; 95% Cl, 0.91-4.97) or drinking only (OR=2.11; 0.91-4.89), and the multivariable OR was 1.20 (95% Cl, 0.41-3.57). Neither ApoA2-ATQ/ATQ nor ApoA2-ATQ/AT was associ-ated with the risk of myocardial infarction. Conclusions Our nested case-control study did not show a significant association of ApoA2 isoforms with a risk of myocardial infarction.