Persistent income-based disparities in clinical outcomes of cardiac surgery across the United States: A contemporary appraisal

Objective

Although national efforts have aimed to improve the safety of inpatient operations, income-based inequities in surgical outcomes persist, and the evolution of such disparities has not been examined in the contemporary setting. We sought to examine the association of community-level household income with acute outcomes of cardiac procedures over the past decade.

Methods

All adult hospitalizations for elective coronary artery bypass grafting/valve operations were tabulated from the 2010-2020 Nationwide Readmissions Database. Patients were stratified into quartiles of income, with records in the 76th to 100th percentile designated as highest and those in the 0 to 25th percentile as lowest. To evaluate the change in adjusted risk of in-hospital mortality, complications, and readmission over the study period, estimates were generated for each income level and year.

Results

Of approximately 1,848,755 hospitalizations, 406,216 patients (22.0%) were classified as highest income and 451,988 patients (24.4%) were classified as lowest income. After risk adjustment, lowest income remained associated with greater likelihood of in-hospital mortality (adjusted odds ratio, 1.61, 95% CI, 1.51-1.72), any postoperative complication (adjusted odds ratio, 1.19, CI, 1.15-1.22), and nonelective readmission within 30 days (adjusted odds ratio, 1.07, CI, 1.05-1.10). Overall adjusted risk of mortality, complications, and nonelective readmission decreased for both groups from 2010 to 2020 (P < .001). Further, the difference in risk of mortality between patients of lowest and highest income decreased by 0.2%, whereas the difference in risk of major complications declined by 0.5% (both P < .001).

Conclusions

Although overall in-hospital mortality and complication rates have declined, low-income patients continue to face greater postoperative risk. Novel interventions are needed to address continued income-based disparities and ensure equitable surgical outcomes.