Plasma levels of apolipoproteins C-III, A-IV, and E are independently associated with stable atherosclerotic cardiovascular disease

BACKGROUND AND AIMS Dyslipidemia is a major risk factor for atherosclerotic cardiovascular disease (ASCVD). As key regulators of lipoprotein metabolism, apolipoproteins (apos) are discussed as vascular risk factors. This study aimed to analyze associations of major plasma apos with coronary artery disease (CAD), peripheral artery disease (PAD) and carotid artery plaque (CAP) to elucidate their diagnostic potential in risk assessment. METHODS ApoA-I, apoA-II, apoA-IV, apoB-100, apoC-I, apoC-III, apoE, and apoJ were simultaneously quantified in 3 \textgreekmL EDTA-plasma by LC-MS/MS in a case-control subgroup of the Leipziger LIFE-Heart Study (N = 911). Confounder analysis with demographic, clinical covariates and serum lipids, cardiac, inflammatory, and hepatic markers were performed. Apos were associated with CAD, CAP, and PAD in a multivariate regression model. RESULTS Fasting and statin therapy showed strongest effects on apo concentrations. Inverse correlations of HDL-related apos A-I, A-II, A-IV, and C-I were observed for troponin T and interleukin 6. Concentrations of apos A-II, B-100, C-I, and E were decreased under statin therapy. After adjustment for influencing factors and related lipids, only apoB-100 (odds ratio per one SD [OR], 1.39; 95% confidence interval [CI], 1.05-1.84) was independently associated with CAD while apoA-IV (OR, 0.74; 95% CI 0.58-0.95) indicated PAD. ApoB-100 (OR, 1.55; 95% CI, 1.18-2.04), apoC-III (OR, 1.30; 95% CI, 1.06-1.58), and apoE (OR, 1.34; 95% CI, 1.13-1.58) were associated with CAP. CONCLUSIONS Triglyceride rich lipoproteins (TRLs) associated apos A-IV, B-100, C-III, and E are independently associated with stable ASCVD, providing further evidence for a potential role of TRLs in atherogenesis.