Lipoprotein and apolipoprotein profile in men with ischemic stroke. Role of lipoprotein(a), triglyceride-rich lipoproteins, and apolipoprotein E polymorphism.

Abstract

The role of lipoprotein abnormalities in the development of ischemic cerebrovascular disease has not been sufficiently clarified. The aim of this study was to identify the lipoprotein profile in ischemic cerebrovascular disease and the possible role of apolipoprotein E polymorphism. The relation between the concentrations of lipoprotein(a), intermediate density lipoproteins, apolipoprotein A-I, apolipoprotein B, apolipoprotein E, and other lipoproteins was studied in 100 men with ischemic cerebrovascular disease (48 atherothrombotic, 28 lacunar, and 24 of unknown type) and in 100 healthy age-matched men as a control group. Patients with ischemic cerebrovascular disease had significantly higher levels of lipoprotein(a), lipids carried by intermediate density lipoproteins, and low density lipoprotein cholesterol and lower levels of high density lipoproteins than control subjects. Patients with atherothrombotic infarction had higher total serum cholesterol and low density lipoprotein cholesterol concentrations than patients with lacunar infarction. To assess lipoprotein abnormalities in normolipidemic subjects, a subgroup of 38 patients with ischemic cerebrovascular disease and 53 control subjects, both with serum cholesterol levels < 5.2 mmol/l (200 mg/dl) and triglycerides < 2.3 mmol/l (200 mg/dl), was analyzed. Serum lipoprotein(a), lipids carried by very low density lipoproteins and intermediate density lipoproteins, and low density lipoprotein triglycerides were significantly higher in normolipidemic patients compared with normolipidemic control subjects, whereas high density lipoprotein cholesterol levels were lower. Apolipoprotein E polymorphism in our ischemic cerebrovascular patients differed from that of the control group, with the epsilon 4 allele being more prevalent. Increased serum lipoprotein(a) levels and intermediate density lipoprotein abnormalities together with decreased high density lipoprotein levels are major risk factors for ischemic cerebrovascular disease, even in normocholesterolemic and normotriglyceridemic subjects. Finally, the epsilon 4 allele could probably be a predisposing genetic marker for ischemic cerebrovascular disease.