Lipoprotein(a) is an independent risk factor for myocardial infarction at a young age

We quantified lipoprotein(a) [Lp(a)] immunochemically in young (less than 46 y) male survivors of myocardial infarction and in age-matched controls recruited from participants of the Prospective Cardiovascular Münster (PROCAM) study. We further determined apolipoprotein E polymorphism and measured triglycerides, total cholesterol, high- and low-density lipoprotein cholesterol (HDL and LDL), and apolipoproteins AI, AII, and B in the serum of these subjects. Lp(a) concentrations in serum were not correlated with other well-recognized risk factors for early myocardial infarction such as apolipoproteins AI and B, LDL cholesterol, and HDL cholesterol. Apolipoprotein E polymorphism did not affect Lp(a) concentrations, but had a major influence on apolipoprotein B concentration. Lp(a) concentrations were not influenced by age. Our data suggest that (a) an increased concentration of Lp(a) constitutes an independent risk factor for early myocardial infarction and (b) the concentrations of Lp(a) and LDL cholesterol (apolipoprotein B) in serum are under separate metabolic control.