Environmental justice index and prevalence of asthma and COPD in US neighborhoods- a population-based study

Background: The independent effects of social and environmental factors on asthma and chronic obstructive pulmonary disease (COPD) are well-documented, but less is known about their combined impact across US neighborhoods. This study aimed to determine the combined and individual associations of neighborhood-level social vulnerability and environmental burden with the prevalence of asthma and COPD. Methods: This cross-sectional study analyzed 71,677 US census tracts, linking the 2022 CDC Environmental Justice Index (EJI) rankings and its subcomponents (environmental burden module EBM and social vulnerability module SVM) to the 2023 CDC PLACES dataset. Multivariable quasi-Poisson regression with an offset function was used to compare covariate-adjusted risk ratios of health indicators across quartiles of neighborhood socio-environmental burden. Findings: Among the 71,677 neighborhoods studied, the median proportion of females was 50.90%. The median proportions of individuals aged 18 to 44, 45 to 64, and ≥65 were 30.6%, 26.7%, and 15.3%, respectively, with 22.6% of the Hispanic population. Asthma and COPD prevalence rates increased with increasing EJI and EBM quartiles. Neighborhoods with the highest socio-environmental burden (Q4 EJI) had significantly higher rates of asthma (RR:1.102, 95% CI: 1.087-1.117, p < 0.001) and COPD (RR:1.156, 95% CI:1.141-1.172, p < 0.001) compared to neighborhoods with the lowest burden (Q1 EJI), after adjusting for covariates. Similarly, neighborhoods with the highest environmental burden (Q4 EBM) had higher rates of asthma (RR: 1.091, 95% CI: 1.064-1.118, p < 0.001) and COPD (RR:1.099, 95% CI: 1.070-1.129, p < 0.001) compared with Q1 EBM, after adjusting for SVM and other covariates. Interpretation: A higher prevalence of obstructive lung disease is associated with neighborhoods experiencing high cumulative socio-environmental burden. Environmental burden showed an independent association with asthma and COPD prevalence, even after adjusting for social vulnerability and other factors. Funding: None.