Abstract P161: Drug-Eluting Stent Utilization and Post-Coronary Revascularization Procedure Mortality: Do Racial Disparities Matter?

Abstract

Background: Besides being a major risk factor for coronary artery disease (CAD), diabetes mellitus (DM) also worsens CAD patients’ prognosis. Percutaneous coronary intervention (PCI) with stenting is an effective treatment procedure for certain categories of CAD patients with DM (CAD-DM). Newer drug-eluting stents (DES) were developed to minimize the occurrence of restenosis known to hinder PCI with older non-drug-eluting stents (non-DES). We hypothesized that disparities in DES utilization and post-procedure mortality would exist in CAD-DM patients. Methods: We conducted a retrospective cohort study of in-hospital mortality in 132,934 CAD-DM patients [mean+SD age: 65.3+11.4 years; 62.7% (83,409 of 132,934) males] after PCI with DES and non-DES in the years 2007,2009. Patient race was classified as white, black, or other Asian, Pacific Islander, Native American). Due to short length of stay, in-hospital death was defined as a binary variable (discharged alive vs. deceased). Multivariable logistic regression was used to obtain adjusted odds ratios (ORs) for in-hospital death after DES and non-DES PCI in relation to patients’ race, adjusting for confounders: age, gender, comorbidities, number of stents inserted, number of vessels treated, socio-economic status, emergency department (ED) admission, rural/urban area status. Results: Blacks were less likely to receive newer DES stent than any other racial group: 75.7% blacks, 76.9% whites, 79.0% other (p<0.04). Blacks were more likely to undergo an emergency rather than planned procedure: 45.7% blacks, 39.8% whites, and 42.7% other were ED-admitted (p<0.01). In adjusted multivariable analysis, controlling for the type of stent and confounding factors, post-PCI mortality in blacks was similar to whites (adjusted OR 0.824, 95% CI: 0.672-1.010, p=0.06), but in other was higher than in whites (adjusted OR 1.284, 95% CI: 1.151-1.434, p<0.001). Conclusions: Racial disparities exist in DES utilization by CAD-DM patients and in post-PCI in-hospital mortality: blacks are least likely to receive DES, but patients of other racial groups are more likely to die after PCI. Further studies investigating the mechanisms responsible for these disparities are warranted.