Socioeconomic Disparities in Patients With Cardiogenic Shock Treated With Extracorporeal Support.

Abstract

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a resource-intensive therapy that can be used in severe cardiogenic shock (CS). Socioeconomic factors are known determinants of cardiovascular outcomes, yet their association with mortality among patients receiving mechanical circulatory support remains unclear. We conducted a retrospective cohort study using the Healthcare Cost and Utilization Project National Inpatient Sample, including adult hospitalizations with CS receiving VA-ECMO between 2018 and 2022. Exposure was Zone Improvement Plan (ZIP) code-level median household income quartile. The primary outcome was in-hospital mortality. We used multivariable regression to estimate risk ratios and Cox-proportional hazards for time-to-event analyses, adjusting for confounders. The 3,032 hospitalizations were evenly distributed across income quartiles. Compared with the lowest-income quartile, the adjusted mortality risk ratio of the second (adjusted risk ratio [aRR], 0.97; 95% confidence interval [CI], 0.86-1.09) and third quartiles (aRR, 0.94; 95% CI, 0.84-1.05) had no significant difference. The highest-income quartile had a significantly lower risk of in-hospital mortality (aRR, 0.83; 95% CI, 0.74-0.94). Time-to-event analyses showed a lower adjusted hazard of death for the fourth versus first quartile (adjusted hazard ratio [aHR], 0.76; 95% CI, 0.64-0.89), whereas second and third quartiles were not significantly different. These findings suggest that disparities persist among patients receiving resource-intensive life-support therapies, highlighting the need to measure socioeconomic variables and address structural factors influencing outcomes in critical care.