Apolipoprotein E genotype and outcome in aneurysmal subarachnoid hemorrhage

Abstract

Background and Purpose - Active management of ruptured intracranial aneurysm in subarachnoid hemorrhage is indicated in patients with favorable prognosis. Outcome prediction is based on patient characteristics and clinical and radiological factors. Current clinical grading scales are imprecise, with low interobserver reproducibility. Therefore, outcome prediction remains inconsistent and decision making becomes difficult, especially for patients with poor clinical grade. Methods - The possible relationship between apolipoprotein E genotype and the outcome of patients suffering spontaneous subarachnoid hemorrhage was investigated. A prospective study was conducted on all patients with spontaneous aneurysmal subarachnoid hemorrhage admitted to our unit during a 2-year period. All patients were managed according to standard protocol, and treatments were given according to their clinical grading. Patient characteristics, clinical grade, radiological grade, and apolipoprotein E genotype were documented. The focus of the study was the 6-month neurological outcome for this group of patients after they were discharged. Results - Seventy-two patients with aneurysmal subarachnoid hemorrhage were admitted to the Prince of Wales Hospital in Shatin, Hong Kong, China, from February 1998 to February 2000. Their ages ranged from 24 to 95 years of age, with a mean (SD) age of 58.3 (15.0) years. Apolipoprotein Eε4 was found in 15 patients (21%). At 6 months, Glasgow Outcome Scale score ≤3 was found in 29 patients (40%). Univariate analysis showed that older patients (odds ratio [OR], 1.03; 95% CI, 1.00 to 1.07; P=0.07) and patients with poor Fisher's grade (OR, 4.5; 95% CI, 1.3 to 15.2; P=0.01), poor World Federation of Neurological Surgeons grade (OR, 5.8; 95% CI, 1.9 to 17.8; P=0.002), or apolipoprotein Eε4 (OR, 6.0; 95% CI, 1.7 to 21.3; P=0.006) were more likely to attain unfavorable outcome at 6 months. The additional effect of apolipoprotein Eε4 remained significant in the multiple logistic regression model (OR, 11.3; 95% CI, 2.2 to 57.0; P=0.003); the gain in predictive performance was not significant (P=0.26). Conclusions - Apolipoprotein Eε4 genotype is related to poor outcome in patients with subarachnoid hemorrhage.