Body Mass and Atherogenic Dyslipidemia as Major Determinants of Blood Levels of B-Type Natriuretic Peptides in Arab Subjects With Acute Coronary Syndromes

Abstract

The plasma B-type natriuretic peptide (BNP) level is elevated in cardiac ischemia and may be useful in assessing prognosis in acute coronary syndromes (ACS). This study aimed to: (1) establish BNP levels and its determinants in a healthy Gulf Arab population and in a group of patients with acute myocardial infarction and (2) investigate associations between BNP levels and markers of myocardial damage (ejection fractions, cardiac troponin I [cTnI] levels) and inflammation (serum C-reactive protein [CRP]). We studied 2 groups of Arab subjects: (1) Healthy control (HC), 142 healthy control subjects; (2) Coronary heart disease (CHD), 257 patients with proven acute myocardial infarction within 1 day of admission. Each subject was assessed clinically, and ejection fractions (left ventricular ejection fraction [LVEF]) were determined by echocardiography in those with CHD. Fasting blood samples were processed for full blood counts and serum glucose, urea, creatinine, uric acid, and lipids (total cholesterol [TC], triglycerides [TG], high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein [LDL], and apolipoprotein B [apoB]), cTnI, BNP, and high-sensitivity (hs) CRP levels. The results were compared between groups, and the associations of BNP with other parameters were explored. In comparison to HC, the CHD group had a greater waist-hip ratio (WHR) (P < 0.01), worse atherogenic profile, worse renal function, and higher values for CRP and BNP (all P < 0.001). There were no significant differences in values for BNP related to age, diabetes, hypertension, WHR, and hematocrit, although there was a consistent trend in both HC and CHD groups toward a negative relationship of BNP with body mass, TG, and apoB levels, and a positive relationship with HDL, independent only for HDL and apoB on multiple logistic regression. No correlations could be established with cTnI, CRP, and LVEF. The patterns of cross-correlations did not differ significantly with diabetic status. In an Arab population with CHD, blood levels of BNP are higher than in a healthy control population and appear correlated to body mass and atherogenic lipids but not CRP, troponin, or ejection fraction. BNP levels did not appear to be influenced by the classical CHD risk factors of diabetes, hypertension, cigarette smoking, hematocrit, or WHR. The independent link with atherogenic dyslipidemia suggests that BNP is important in atherogenesis and may not be just an index of cardiac contractile dysfunction.