Object-Approximately 20% of patients with an intracranial saccular aneurysm report a family history of intracranial aneurysm (IA) or subarachnoid hemorrhage. A better understanding of predictors of aneurysm detection in familial IA may allow more targeted aneurysm screening strategies.
Methods-TheFamilial Intracranial Aneurysm (FIA) study is a multicenter study, in which the primary objective is to define the susceptibility genes related to the formation of IA. First-degree relatives (FDRs) of those affected with IA are offered screening with magnetic resonance (MR) angiography if they were previously unaffected, are ≥ 30 years of age, and have a history of smoking and/or hypertension. Independent predictors of aneurysm detection on MR angiography were determined using the generalized estimating equation version of logistic regression.Results-Among the first 303 patients screened with MR angiography, 58 (19.1%) had at least 1 IA, including 24% of women and 11.7% of men. Ten (17.2%) of 58 affected patients had multiple aneurysms. Independent predictors of aneurysm detection included female sex (odds ratio [OR] 2.46, p = 0.001), pack-years of cigarette smoking (OR 3.24 for 20 pack-years of cigarette smoking compared with never having smoked, p < 0.001), and duration of hypertension (OR 1.26 comparing those with 10 years of hypertension to those with no hypertension, p = 0.006).Conclusions-In the FIA study, among the affected patients' FDRs who are > 30 years of age, those who are women or who have a history of smoking or hypertension are at increased risk of suffering an IA and should be strongly considered for screening. To clarify further the occurrence of IA detection on brain MR angiography studies in families with several members affected, we report the initial results of MR angiography screening of FDRs-siblings, parents, and children-of those affected with an IA in a multicenter study of familial IA. We also report the predictors of IA detection on brain MR angiography among these FDRs.
Clinical Materials and MethodsThe FIA study is an international, multicenter study including 26 clinical centers, which represents 41 recruitment sites in North America, New Zealand, and Australia. 2 The study was approved by the institutional review board/ethics committee at each of the study centers and recruitment sites.Families with multiple members in whom IAs were diagnosed were enrolled to identify the chromosomal regions associated with an increased risk of IA and to determine the effects of environmental factors on the expression of genes within these regions. Individuals with either ruptured or unruptured IAs were considered to have the phenotype. Patients were excluded if they had a fusiform IA; an intranidal aneurysm with an arteriovenous malformation; a family history of polycystic kidney disease, Ehlers-Danlos syndrome, Marfan syndrome, fibromuscular dysplasia, or moyamoya syndrome; or if informed consent could not be obtained from the patient or family members.Detailed medical records and the informa...