County Poverty Concentration and Disparities in Unintentional Injury Deaths: A Fourteen-Year Analysis of 1.6 Million U.S. Fatalities.

Unintentional injury is the fourth leading cause of death in the United States, and mortality due to injury has risen over the past decade. The social determinants behind these rising trends have not been well documented. This study examines the relationship between county-level poverty and unintentional injury mortality in the United States from 1999-2012. Complete annual compressed mortality and population data for 1999-2012 were obtained from the National Center for Health Statistics and linked with census yearly county poverty measures. The outcomes examined were unintentional injury fatalities, overall and by six specific mechanisms: motor vehicle collisions, falls, accidental discharge of firearms, drowning, exposure to smoke or fire, and unintentional poisoning. Age-adjusted mortality rates and time trends for county poverty categories were calculated, and multivariate negative binomial regression was used to determine changes over time in both the relative risk of living in high poverty concentration areas and the population attributable fraction. Age-adjusted mortality rates for counties with > 20% poverty were 66% higher mortality in 1999 compared with counties with < 5% poverty (45.25 vs. 27.24 per 100,000; 95% CI for rate difference 15.57,20.46), and that gap widened in 2012 to 79% (44.54 vs. 24.93; 95% CI for rate difference 17.13,22.09). The relative risk of living in the highest poverty counties has increased for all injury mechanisms with the exception of accidental discharge of firearms. The population attributable fraction for all unintentional injuries rose from 0.22 (95% CI 0.13,0.30) in 1999 to 0.35 (95% CI 0.22,0.45) in 2012. This is the first study that uses comprehensive mortality data to document the associations between county poverty and injury mortality rates for the entire US population over a 14 year period. This study suggests that injury reduction interventions should focus on areas of high or increasing poverty.

Neighborhood-level stressors, social support, and diurnal patterns of cortisol: the Chicago Community Adult Health Study.

Neighborhood disadvantage has consistently been linked to increased rates of morbidity and mortality, but the mechanisms through which neighborhood environments may get "under the skin" remain largely unknown. Differential exposure to chronic environmental stressors has been identified as a potential pathway linking neighborhood disadvantage and poor health, particularly through the dysregulation of stress-related biological pathways such as cortisol secretion, but the majority of existing observational studies on stress and neuroendocrine functioning have focused exclusively on individual-level stressors and psychosocial characteristics. This paper aims to fill that gap by examining the association between features of the neighborhood environment and the diurnal cortisol patterns of 308 individuals from Chicago, Illinois, USA. We found that respondents in neighborhoods with high levels of perceived and observed stressors or low levels of social support experienced a flatter rate of cortisol decline throughout the day. In addition, overall mean cortisol levels were found to be lower in higher stress, lower support neighborhoods. This study adds to the growing evidence of hypocortisolism among chronically stressed adult populations and suggests hypocortisolism rather than hypercortisolism as a potential mechanism linking social disadvantage to poor health.