American Journal of Epidemiology Advance Access originally published online on October 31, 2006
American Journal of Epidemiology 2007 165(3):279-287; doi:10.1093/aje/kwk005
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ORIGINAL CONTRIBUTIONS |
Neighborhood Environment and Risk of Ischemic Stroke
The Brain Attack Surveillance in Corpus Christi (BASIC) Project
1 Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI
2 Stroke Program, University of Michigan Medical School, Ann Arbor, MI
Reprint requests to Dr. Lewis B. Morgenstern, Stroke Program, University of Michigan Medical School, 1500 East Medical Center Drive, TC 1920/0316, Ann Arbor, MI 48109-0316 (e-mail: Lmorgens{at}umich.edu).
The authors explored whether neighborhood-level characteristics are associated with ischemic stroke and whether the association differs by ethnicity, age, and gender. Using data from the Brain Attack Surveillance in Corpus Christi Project (January 2000–June 2003), they identified cases of ischemic stroke (n = 1,247) from both hospital and out-of-hospital sources. Census tracts served as proxies for neighborhoods, and neighborhood socioeconomic status scores were constructed from census variables (higher scores represented less disadvantage). In Poisson regression analyses comparing the 90th percentile of neighborhood score with the 10th, the relative risk of stroke was 0.49 (95% confidence interval (CI): 0.41, 0.58). After adjustment for age, gender, and ethnicity, this association was attenuated (relative risk (RR) = 0.79, 95% CI: 0.63, 1.00). There was no ethnic difference in the association of score with stroke (p for interaction = 0.79). Significant effect modification was found for age (p for interaction < 0.001) and gender (p for interaction = 0.04), with increasing scores being protective against stroke in men and younger persons. Associations were attenuated after adjustment for education (men: RR = 0.77, 95% CI: 0.55, 1.07; persons aged <65 years: RR = 0.65, 95% CI: 0.41, 1.02). Neighborhood characteristics may influence stroke risk in certain gender and age groups. Mechanisms for these associations should be examined.
cerebrovascular accident; ethnic groups; residence characteristics; social class
Abbreviations: BASIC, Brain Attack Surveillance in Corpus Christi; CI, confidence interval; RR, relative risk; SD, standard deviation; SES, socioeconomic status