Prevalence of apolipoprotein E phenotypes in ischemic cerebrovascular disease: A case-control study

Abstract

Background and Purpose: Apolipoprotein E polymorphism may influence the early development of coronary artery disease. We investigated the putative role of apolipoprotein E phenotypes in cerebral infarction. Methods: The apolipoprotein E phenotypes of 69 patients (mean�±SD age, 72�±11 years) who had suffered completed stroke or a transient ischemic attack and 68 sex- and age-matched control subjects free of cerebrovascular disease were determined by isoelectric focusing. The relative frequency of the apolipoprotein E phenotypes in the general population was estimated in 498 healthy blood donors (mean age, 37 years). Results: The prevalences of hypertension, diabetes mellitus, obesity, and intermittent claudication were significantly higher in patients than in control subjects. Serum lipid and apolipoprotein B concentrations and the composition of very low density lipoproteins were not significantly different between patients and control subjects. Apolipoprotein A-I and E levels were significantly lower in patients. Cholesterol levels were higher in male patients than in male control subjects (5.10�±1.46 versus 4.41 �±0.80 mmol/L; p=0.036), and the ratio of apolipoprotein A-I to B was lower (0.77�±0.29 versus 1.03�±0.37; p<0.001). The E3/E3 phenotype was more frequent in control subjects (85%) than in patients (72.5%; p<0.05) and healthy blood donors (64%;p<0.02). The E3/E2 phenotype was more frequent in patients (10.1%) than in control subjects (1.4%; p<0.05). A stepwise logistic regression showed that the presence of stroke was significantly related to high blood pressure (p<0.0001), low apo E levels (p<0.008), obesity (p<0.041), the apo E phenotype (p<0.05), and diabetes mellitus (p<0.05). Conclusions: The E3/E3 phenotype may protect against early vascular morbidity, and the ∈2 gene may be a risk factor for cerebrovascular morbidity, possibly related to diabetes, hypertension, and/or obesity. © 1993 American Heart Association, Inc.