Association Between Race, Illness Severity, and Mortality in Children Undergoing Cardiac Surgery

Thesis (Master's)--University of Washington, 2018Background: Prior studies have demonstrated that non-white race/ethnicity and insurance status are associated with mortality after congenital heart surgery. It remains unknown whether non-white children have a higher mortality due to limited access to care, resulting in higher illness severity scores on admission. We hypothesize that non-white children undergoing congenital heart surgery have a higher severity of illness score on admission and, in turn, have higher odds of mortality than their white counterparts. Methods: We performed a retrospective analysis of registry data from the Virtual Pediatric Systems dataset from 2009-2016. All children (less than 18 years of age) undergoing congenital cardiac surgery and admitted to an intensive care unit (ICU) in one of the 81 participating institutions were included (n= 37,056). Results: In a univariate analysis, there was significant variation in severity of illness scores across race/ethnicity groups. Multivariate regression models demonstrated a small but significant association between black race and higher severity of illness scores compared with white race, after adjustment for insurance status and other covariates. In multivariate models that examined ICU mortality, black patients remained at increased odds of mortality (Odds Ratio: 1.31, 95% Confidence Interval: 1.07-1.61) when compared with white children, adjusting for illness severity, age, gender, prematurity, weight, operating room (OR) status, number of complex chronic conditions, Risk Adjustment for Congenital Heart Surgery (RACHS) category, and type of insurance. Conclusions: Black children undergoing cardiac surgery have higher odds of death compared with white children, despite adjustment for illness severity on admission to the ICU. These results suggest that severity of illness may not be the main driver of health disparities in children undergoing congenital heart surgery