Racial Differences in Clostridium difficile Infection Rates Are Attributable to Disparities in Health Care Access

Abstract

This study confirms previously reported racial differences in Clostridium difficile infection (CDI) rates in the United States and explores the nature of those differences. We conducted a retrospective study using the 2010 Nationwide Inpatient Sample, the largest all-payer database of hospital discharges in the United States. We identified hospital stays most likely to include antibiotic treatment for infections, based on hospital discharge diagnoses, and we examined how CDI rates varied, in an attempt to distinguish between genotypic and environmental racial differences. Logistic regressions for the survey design were used to test hypotheses. Among patients likely to have received antibiotics, white patients had higher CDI rates than black, Hispanic, Asian, and Native American patients (P < 0.0001). CDI rates increased with higher income levels and were higher for hospitalizations paid by private insurance versus those paid by Medicaid or classified as self-pay or free care (P < 0.0001). Among patients admitted from skilled nursing facilities, where racial bias in health care access is less, racial differences in CDI rates disappeared (P = 1.0). Infected patients did not show racial differences in rates of complicated CDI or death (P = 1.0). Although white patients had greater CDI rates than nonwhite patients, racial differences in CDI rates disappeared in a population for which health care access was presumed to be less racially biased. This provides evidence that apparent racial differences in CDI risks may represent health care access disparities, rather than genotypic differences. CDI represents a deviation from the paradigm that increased health care access is associated with less morbidity.