Association of LpPLA2 with coronary artery disease a hospital-based case control study

Abstract

Coronary artery disease (CAD) in Asian-Indians is characterised by an earlier onset and more severe disease when compared to Western populations. It is estimated that about 20% of patients presenting with an acute coronary syndrome do not have any of the conventional risk factors for CAD. To assess the risk posed by each of the newer risk factors; alongside conventional risk factors namely diabetes, hypertension, dyslipidaemia for coronary artery disease and to compare the relative risk in a case-control design. Department of Cardiology, XXX Institute of Medical sciences (XXX). Case control study design. Cases are as any individual with coronary artery disease and controls included patients with non-coronary conditions. Dependant variable: coronary artery disease (CAD); Independent variables: Lp PLA2, Lp(a), Apo(a), Apo(b), Ratio (Apo B/Apo A); Other predictors- diabetes mellitus, hypertension, dyslipidaemia, tobacco use Categorical variables were presented as frequencies and percentages. Chi-square test and binary logistic regression analysis was used to study the comparison and association of the categorical risk factors with the disease status, respectively. Software used was SPSS version 20.0. A total of 253 participants aged between 19 and 90 years; 140 cases and 113 controls were enrolled in this study. Except for the hs-CRP level, alcohol consumption and LDL, all the other risk factors were seen significantly associated with the coronary artery disease; dyslipidaemia (10.8, 95% CI 3.29-35.37), gender- male (4.68, 95% CI 2.12-10.30), diabetes mellitus (3.3, 95% CI 1.6 -6.77), lipoprotein(a) more than 30mg% (2.34, 95% CI 1.06-5.15) and hypertension (2.48, 95% CI 1.14-5.39). Conventional risk factors namely diabetes, hypertension and dyslipdaemia showed a statistically significant association with CAD while from among the biochemical markers the association was statistically significant only for Lp(a) when compared both between cases and controls and also in cases < age 50 years. The other biochemical risk factors namely Lp-PLA2, Apo(A1) and Apo(b) showed a weak degree of association with CAD. In the present study we analyse the role of inflammatory mediators of CAD (hs-CRP, Lp-PLA2), pro-thrombotic markers [Lp(a)] alongside the lipid fractions apoB, apo A and their ratio to assess which of these biochemical markers predisposed one to CAD through assessment of the relative risk.