Article

Racial/Ethnic differences in longitudinal risk of intracranial hemorrhage in brain arteriovenous malformation patients.

Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94115, USA.
Stroke (impact factor: 5.73). 09/2007; 38(9):2430-7. DOI:10.1161/STROKEAHA.107.485573
Source: PubMed

ABSTRACT Race/ethnicity is associated with overall incidence of intracranial hemorrhage (ICH), but its impact in patients with brain arteriovenous malformation is unknown. We evaluated whether race/ethnicity was a risk factor for ICH in the natural course in a large, multiethnic cohort of patients with brain arteriovenous malformation followed longitudinally.
Data were collected prospectively for patients with brain arteriovenous malformation evaluated at the University of California, San Francisco (n=436) and retrospectively through databases and chart review in the 20 hospitals of the Kaiser Permanente Medical Care Program (n=1028). Multivariate Cox regression was performed to assess the influence of race/ethnicity on subsequent ICH, adjusting for risk factors. Cases were censored at first treatment, loss to follow-up, or death.
Average follow up was 4.7+/-8.0 years for Kaiser Permanente Medical Care Program patients and 2.8+/-7.3 years for University of California, San Francisco patients with no difference in time to ICH between cohorts (log rank P=0.57). The annualized 5-year ICH rate was 2.1% (3.7% for ruptured at presentation; 1.4% for unruptured). Initial ICH presentation (hazard ratio: 3.0, 95% CI: 1.9 to 4.9, P<0.001) and Hispanic race/ethnicity (hazard ratio: 1.9, 95% CI: 1.1 to 3.3, P=0.02) were independent predictors of ICH, adjusting for age, gender, cohort, and a cohort-age interaction. The ICH risk for Hispanics versus whites increased to 3.1 (95% CI: 1.3 to 7.4, P=0.013) after further adjusting for arteriovenous malformation size and deep venous drainage in a subset of cases with complete data. Similar trends were observed for blacks (hazard ratio: 2.1, 95% CI: 0.9 to 4.8, P=0.09) and Asians (hazard ratio: 2.4, 95% CI: 0.8 to 7.1, P=0.11), although nonsignificant.
This study reports the first description of race/ethnic differences in brain arteriovenous malformation, with Hispanics at an increased risk of subsequent ICH compared with whites.

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Keywords

20 hospitals
 
annualized 5-year ICH rate
 
arteriovenous malformation size
 
brain arteriovenous malformation
 
Cases
 
complete data
 
first description
 
hazard ratio
 
Hispanic race/ethnicity
 
Hispanics
 
Initial ICH presentation
 
intracranial hemorrhage
 
Kaiser Permanente Medical Care Program
 
Kaiser Permanente Medical Care Program patients
 
Multivariate Cox regression
 
San Francisco
 
San Francisco patients
 
Similar trends
 
subsequent ICH
 
venous drainage