Cerebral hemorrhage and apoE

The epsilon 4 allele of apolipoprotein E (apoE) is found more commonly amon g patients with Alzheimer's disease (AD) than in the normal population. Apo E is associated with brain amyloid, a component of cerebral amyloid angiopa thy (CAA), which is both a pathological feature of AD and a frequent cause of lobar intracerebral hemorrhage (ICH). We hypothesized that the frequency of epsilon 4 allele is higher in patients with CAA-related ICH than in hyp ertensive ICH and in the normal population. To test this hypothesis we comp ared the frequency of apoE alleles in four populations: 24 patients with lo bar ICH, 24 matched patients with hypertensive ICH, 24 matched normal contr ols, and 173 population controls. Although there was a tendency to a higher frequency of apoE epsilon 4 in lobar ICH patients, we found no significant differences in the frequency of this allele between the four studied popul ations. In addition we did not confirm the finding of some authors of a hig her frequency of apoE epsilon 2 in patients with lobar ICH than in the norm al population. Previous studies on the subject are discussed. The relations hip between apoE polymorphism and lobar CAA-related ICH remains to be clear ly defined.