Introduction: Racial residential segregation results in increased exposure to adverse neighborhood environments for African Americans; however, the impact of segregation on ideal cardiovascular health (CVH) has not been examined in large, socioeconomically diverse African American samples. Using a novel spatial measure of neighborhood-level racial residential segregation, we examined the association between segregation and ideal CVH in the Jackson Heart Study (JHS).
Hypothesis: Racial residential segregation will be associated with worse cardiovascular health among African American adults.
Methods: The sample included 4,354 men and women ages 21-93 from the baseline exam of the JHS (2000-2004). Racial residential segregation was assessed at the census-tract level. Data on racial composition (% African American) from the 2000 US Census was used to calculate the local Gi* statistic- a spatially-weighted z-score that represents how much a neighborhood’s racial/ethnic composition deviates from the larger metropolitan area. Ideal CVH was assessed using the AHA Life’s Simple Seven (LS7) index which includes 3 behavioral (nutrition, physical activity, and smoking) and 4 biological (systolic BP, glucose, BMI, and cholesterol) metrics of CVH. Multivariable regression models were used to test associations between segregation and the LS7 index continuously (range: 0-14) and categorically (Inadequate: 0-4; Average: 5-9; and Optimal: 10-14). Covariates included age, sex, income, education, and insurance status.
Results: The average LS7 summary score was 7.03 (±2.1) and was lowest in the most racially segregated neighborhood environments (High Segregation: 6.88 ±2.1 vs. Low Segregation: 7.55 ±2.1). The prevalence of inadequate CVH was higher in racially segregated neighborhoods (12.3%) compared to neighborhoods that were the least segregated (6.9%). After adjusting for key socio-demographic characteristics, racial residential segregation was inversely associated with ideal CVH (B=-0.041 ±0.02, p=0.0146). Moreover, a 1-SD unit increase in segregation was associated with a 6% increased odds of having inadequate CVH (OR: 1.06, 95% CI: 1.00-1.12, p=0.0461).
Conclusion: In conclusion, African Americans in racially segregated neighborhoods are less likely to achieve ideal CVH even after accounting for individual-level factors. Policies aimed at restricting housing segregation/discrimination and/or structural interventions designed to improve neighborhood environments may be viable strategies to improving CVH in this at-risk population.