Reduced HDL2 levels in myocardial infarction patients without risk factors for atherosclerosis

Out of a total of 170 patients with a first myocardial infarction, aged below 65 years, consecutively admitted to the Coronary Care Unit of a large urban hospital, only 14 did not present with any risk factor(s) for atherosclerosis (smoking, hypertension, diabetes and obesity). None of these 14 patients showed significant hyperlipidemia. Compared to a control series of normal individuals of the same age (50.0 +/- 5.8 years for males and 61.6 +/- 3.0 years for females), they showed a significant reduction of high-density lipoprotein (HDL)-cholesterol and of apolipoprotein A-I (respectively -18.2 and -9.5%). However, the most striking abnormality was a 30% decrease of the HDL2 mass and of HDL2 cholesterol; both HDL2 and HDL3 had a reduced cholesteryl ester content in the patients. Reduced HDL2 mass and cholesterol levels in plasma, accompanied by significant alterations in HDL subfraction composition, are consistent with a defective cholesterol esterification in HDL. HDL2 deficiency may be a primary alteration in myocardial infarction patients without other significant risk factors.