System Failure: The Spatial Distribution of Black-White Disparities in Septic Mortality and Its Small-Area Correlates

Adam M. Lippert, Pennsylvania State University

Septic mortality, a result of system-wide physiologic dysfunction often resulting from hospital-associated infections, is the tenth leading cause of death in the US. Compared to non-Hispanic Whites, African-Americans are more likely to die from sepsis, though the causes of this disparity are unclear. Regional differences in social disadvantage and consequent inequities in healthcare access may help explain this vexing disparity. Using GIS mapping and methods that account for spatial dependencies, this study reveals several key findings: (1) Rate-ratios of septic mortality cluster across space, such that the ratio of Black-to-White deaths is much higher in some regions than others; (2) Area-based measures of poverty and education are associated with rate-ratios of Black-to-White septic mortality; (3) These associations are attenuated by the availability of hospitals and percent uninsured. The findings suggest that factors associated with social disadvantage and healthcare availability must be augmented to existing explanations for the African-American septic mortality disadvantage.