Objective: To investigate the association between the number of fast food restaurants and ischemic stroke in neighborhoods.
Methods: This work was a prespecified part of the Brain Attack in Corpus Christi (BASIC) project. Ischemic stroke cases were prospectively ascertained in Nueces County, Texas. Home addresses were geocoded and used to establish the census tract for each stroke case. Census tracts were used as proxies for neighborhoods (n = 64). Using a standard definition, fast food restaurants were identified from a commercial list. Poisson regression was used to study the association between the number of fast food restaurants in the neighborhood, using a 1-mile buffer around each census tract, and the risk of stroke in the neighborhood. Models were adjusted for demographics and neighborhood socioeconomic status (SES).
Results: There were 1,247 completed ischemic strokes from January 2000 through June 2003 and 262 fast food restaurants. The median number of fast food restaurants per census tract including buffer was 22 (interquartile range, 12-33). Adjusting for neighborhood demographics and SES, the association of fast food restaurants with stroke was significant (p = 0.02). The association suggested that the risk of stroke in a neighborhood increased by 1% for every fast food restaurant (relative risk, 1.01; 95% confidence interval [CI], 1.00-1.01). The relative risk of stroke comparing neighborhoods in the 75th to the 25th percentile of the distribution of fast food restaurants was 1.13 (95% CI, 1.02-1.25).
Interpretation: Controlling for demographic and SES factors, there was a significant association between fast food restaurants and stroke risk in neighborhoods in this community-based study.