Health disparities attributable to air pollutant exposure in North Carolina: Influence of residential environmental and social factors

Understanding the environmental justice implications of the mortality impacts of air pollution exposure is a public health priority, as some subpopulations may face a disproportionate health burden. We examined which residential environmental and social factors may affect disparities in the air pollution-mortality relationship in North Carolina, US, using a time-stratified case-crossover design. Results indicate that air pollution poses a higher mortality risk for some persons (e.g., elderly) than others. Our findings have implications for environmental justice regarding protection of those who suffer the most from exposure to air pollution and policies to protect their health

Urbanization as a risk factor for aortic stiffness in a cohort in India

<div><p>Urbanization is associated with higher prevalence of cardiovascular disease worldwide. Aortic stiffness, as measured by carotid-femoral pulse wave velocity is a validated predictor of cardiovascular disease. Our objective was to determine the association between urbanization and carotid-femoral pulse wave velocity. The analysis included 6166 participants enrolled in an ongoing population-based study (mean age 42 years; 58% female) who live in an 80 × 80 km region of southern India. Multiple measures of urbanization were used and compared: 1) census designations, 2) satellite derived land cover (crops, grass, shrubs or trees as rural; built-up areas as urban), and 3) distance categories based on proximity to an urban center. The association between urbanization and carotid-femoral pulse wave velocity was tested in sex-stratified linear regression models. People residing in urban areas had significantly (p < 0.05) elevated mean carotid-femoral pulse wave velocity compared to non-urban populations after adjustment for other risk factors. There was also an inverse association between distance from the urban center and mean carotid-femoral pulse wave velocity: each 10 km increase in distance was associated with a decrease in mean carotid-femoral pulse wave velocity of 0.07 m/s (95% CI: -0.09, -0.06 m/s). The association was stronger among older participants, among smokers, and among those with other cardiovascular risk factors. Further research is needed to determine which components in the urban environment are associated with higher carotid-femoral pulse wave velocity.</p></div

Mean unadjusted carotid-femoral pulse wave velocity (m/s) by 20 km distance intervals stratified by cardiovascular disease risk factors and sex.

<p>Lines with lighter symbols and triangle markers represent males and lines with darker symbols and square markers represent females. Solid lines represent groups that have higher levels of cardiovascular disease risk factors (e.g., older, smokers, or higher body mass index) while dashed lines represent groups that have lower levels of cardiovascular disease risk factors. HTN = hypertension; BMI = body mass index; LDL = low density lipoprotein. All tests for trends have p < 0.001 except those indicated by * (p < 0.05 but ≥ 0.001) or ** (p > 0.05).</p

Demographic and health characteristics of PURSE-HIS cohort stratified by sex and community type as defined by census designation (n = 6166).

<p>Demographic and health characteristics of PURSE-HIS cohort stratified by sex and community type as defined by census designation (n = 6166).</p

PURSE-HIS participants, distance categories, and land cover type.

<p>Participant locations are shown as blue dots, the Chennai city center is shown as a green star, the Chennai boundary is shown with a solid black line, and distance from the Chennai city center is noted with dashed lines at 20 km, 40 km, 60 km, and 80 km from the city center.</p

Census designation and land cover classification for mean carotid-femoral pulse wave velocity (cfPWV) by sex.

<p>Bars represent the standard deviation. For census designation, mean cfPWV is shown for urban/semi-urban and rural areas. For land cover classification, mean cfPWV is shown for urban areas, areas with grass/trees, and areas with crops. For all census and land cover comparisons, mean cfPWV is significantly (p < 0.05) higher in men than women. Mean cfPWV is significantly higher for men and women in urban areas than in rural areas as designated by the census or in areas with crops as designated by land cover. Mean cfPWV is also significantly higher for men in areas with grass/trees than in areas with crops.</p

Association between distance in kilometers from urban center and carotid-femoral pulse wave velocity (m/s).

<p>Association between distance in kilometers from urban center and carotid-femoral pulse wave velocity (m/s).</p