Endotoxemia and cardiometabolic biomarkers in patients with acute myocardial infarction. Data from the RICO survey

Abstract

The complex interplay between endotoxemia, inflammation and cardiometabolic diseases including acute myocardial infarction (MI) is poorly understood. From the RICO survey, patients admitted for acute MI were prospectively included (2016 to 2018). Patients with prior coronary artery disease (CAD) or chronic kidney disease were excluded. Blood samples were taken on admission. Endotoxemia was assessed by the LCM-SMS measurement of circulating levels of LPS-derived 3-hydroxymyristate (3HM), a component of the lipid A moiety. Among the 245 patients included, mean age was 62 ± 13 y, most were male (72%), almost half were hypertensive (43%), or current smokers (44%), 38% had hypercholesterolemia, or family history of CAD (31%), median(IQR) BMI was 27(25-29) kg/m 2 and 14% had diabetes. Median LDL-cholesterol was at 132 mg/dL, HDL-cholesterol at 47 mg/dL, total cholesterol at 209 mg/dL and triglycerides (TG) at 116 mg/dL, 3HM levels at 106(83-131) pmol/L. TG levels were the most strongly correlated with LPS levels ( r = 0.201, P = 0.002), beyond HbA 1c ( r = 0.197, P = 0.002), BMI ( r = 0.192, P = 0.003), cholesterol ( r = 0.191, P = 0.003), blood glucose ( r = 0.174, P = 0.006) and age ( r = 0.173, P = 0.007). Inflammatory biomarkers and cytokines (CRP, IL6, IL8, TNFα) did not significantly relate to 3HM levels. When compared with patients without diabetes, patients with diabetes had ≈40% higher levels of 3HM (140 vs. 103 pmol/L, P < 0.001). TG (ß(95%CI) = 0.288(7.757-20.357)) remained an independent determinant of 3HM levels, beyond age (ß(95%CI) = 0.184(0.274-1.374)), and HbA 1c (ß(95%CI) = 0.157(1.764-15.390)). In patients with acute MI, endotoxemia levels related mainly to chronic metabolic disorders including diabetes and hypercholesterolemia. The underlying mechanisms for the LPS-associated TG elevations and its clinical significance at the acute phase of MI remains to be explored.