Incidence of familial intracranial aneurysms in 200 patients: comparison among Caucasian, African-American, and Hispanic populations.

OBJECTIVE: Although the cause of cerebral aneurysms remains unclear, there is clear evidence that genetic predisposition plays a role. Ten percent of patients report an aneurysm in a first-degree family member. However, studies to date have largely involved Caucasian populations. Our goal was to characterize the familial aggregation of intracranial aneurysms in different ethnic groups.
METHODS: We began a prospective, single-center study on patients treated for intracranial aneurysms. Consenting subjects completed a detailed questionnaire regarding the medical history of family members. In families with two or more affected members, asymptomatic first-degree relatives were screened using computed tomographic or magnetic resonance angiography.
RESULTS: In a 2-year period, 292 patients with intracranial aneurysms were treated and 200 were enrolled; these included 124 Caucasians (62%), 34 African-Americans (17%), 38 Hispanics (19%), and 4 Asian-Americans (2%). Forty patients had a family history (20%). The incidence of family history among the different ethnic groups was similar; it was 19.4% in Caucasians, 20.6% in African-Americans, and 21.6% in Hispanics. One Asian-American patient had a family history. Visual inspection of the pedigrees supported autosomal-dominant inheritance with variable penetrance in all ethnic groups.
CONCLUSION: This study examined the incidence of familial cerebral aneurysms in three ethnic groups common to the United States: Caucasian, African-American, and Hispanic. We noted an equivalent rate of familial aneurysms, a finding that has immediate clinical implications. In families that have two or more members with cerebral aneurysms, screening of asymptomatic members should be recommended, regardless of ethnic background.