BACKGROUND AND PURPOSE: Twin and family history studies support a role for genetic factors in @entity64 risk. Because the etiology of @entity385 is heterogeneous, genetic factors may vary by etiologic subtype. We determined the familial aggregation of @entity64 risk in different @entity64 phenotypes and used the results to model estimated sample size requirements for case-control studies. METHODS: One thousand consecutive white subjects with @entity385 and 800 white controls matched for age and sex were recruited. A first-degree family history of @entity64 and @entity583 was obtained by structured interview. @entity64 subtype was determined with the use of modified Trial of @entity10269 in Acute @entity64 Treatment (TOAST) criteria. RESULTS: A family history of @entity64 at < or =65 years was a significant risk factor for @entity66 (odds ratio [OR], 2.24; 95% CI, 1.49 to 3.36; P<0.001) and for @entity6249 (OR, 1.93; 95% CI, 1.25 to 2.97; P=0.003). When only cases aged <or =65 years were considered, these ORs increased to 2.93 (95% CI, 1.68 to 5.13) (P<0.001) and 3.15 (95% CI, 1.81 to 5.50) (P<0.001), respectively. No significant associations were seen for @entity64 or @entity64 of undetermined etiology. CONCLUSIONS: A family history of @entity455 is an independent risk factor for both large-vessel @entity731 and @entity6249 , especially in cases presenting before age 65 years. The estimated sample sizes for case-control studies illustrate how candidate gene studies for @entity385 might be made more effective by focusing on these specific phenotypes, in which the genetic component of the disease appears to be strongest.

Evaluating the genetic component of XXXX subtypes: a family history study.

@entity64 :: ('MESH:D020521', 'Disease') :: ['cardioembolic stroke', 'stroke', 'Stroke'] @entity455 :: ('MESH:D014652', 'Disease') :: ['vascular disease'] @entity66 :: ('MESH:D004194', 'Disease') :: ['large-vessel disease'] @entity6249 :: ('MESH:D059345', 'Disease') :: ['small-vessel disease'] @entity731 :: ('MESH:D050197', 'Disease') :: ['atherosclerosis'] @entity583 :: ('MESH:D009203', 'Disease') :: ['myocardial infarction'] @entity10269 :: ('MESH:C035838', 'Chemical') :: ['Org 10172'] @entity385 :: ('MESH:D002544', 'Disease') :: ['ischemic stroke']
@entity385 :: (MESH:D002544,Disease) :: ['ischemic stroke']
