CIGARETTE-SMOKING AS A DETERMINANT OF HIGH-GRADE CAROTID-ARTERY STENOSIS IN HISPANIC, BLACK, AND WHITE PATIENTS WITH STROKE OR TRANSIENT ISCHEMIC ATTACK

Background and Purpose-We sought to investigate the association of cig arette smoking with high-grade carotid artery stenosis in Hispanic, bl ack, and white patients with cerebral ischemia in two independent samp les. Methods-Prospectively collected data from the Northern Manhattan Stroke Study (NOMASS) (n=431) and the Berlin Cerebral Ischemia Databan k (BCID) (n=483) were used separately for a cross-sectional study esti mating the association between cigarette smoking and high-grade caroti d stenosis (defined as a luminal narrowing of greater than or equal to 60%, diagnosed by duplex and/or Doppler ultrasound). In both studies, cerebral ischemia patients with normal sonographic findings or nonste nosing plaques of their carotid arteries served as a comparison group. Multivariate logistic regression models were used for statistical tes ts to determine the association between smoking and the dependent vari able for high-grade carotid stenosis. Age, sex, hypertension, diabetes , hypercholesterolemia, and race/ethnicity were considered potential c onfounders. Further analyses of the NOMASS data estimated the effect o f the amount of cigarette use and the impact of race/ethnicity. Result s-High-grade carotid stenoses were found in 14% of the NOMASS and in 2 1% of the Berlin patients. In Berlin the entire sample was white, wher eas in New York only 19% of the cohort were white. In both samples, sm oking was independently associated with severe carotid stenosis (NOMAS S: odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1 to 2.0; BCI D: OR, 3.9; 95% CI, 2.4 to 6.4). Patients smoking 20 pack-years or mor e showed a significant association (OR, 2.0; 95% CI, 1.1 to 3.9), wher eas no significant effect was found for lower amounts of cigarette use . In NOMASS, white smokers displayed a significant (OR, 3.2; 95% CI, 1 .1 to 8.9) association with high-grade carotid stenosis, the associati on for black smokers was less strong, and no association was found amo ng Hispanics. Conclusions-Smoking is an independent determinant of sev ere carotid artery stenosis in patients with focal cerebral ischemia. The association differs by race/ethnicity, with the greatest effect ob served among whites.