Coronary revascularization outcomes in relation to skilled nursing facility use following hospital discharge

Background: Observational analyses comparing coronary artery bypass surgery (CABG) and percutaneous coronary intervention (PCI) among elderly or frail patients are likely biased by treatment selection. PCI is typically chosen for frail patients, while CABG is more common for patients with good recovery potential. Hypothesis: We hypothesized that skilled nursing facility (SNF) use after revascularization is a measure of relative frailty associated with outcomes following coronary revascularization. Methods: We used a 20 percent sample of Medicare beneficiaries aged 65 years or older who received inpatient PCI or CABG between 2007–2014. Key explanatory variables were the revascularization strategy and SNF use after revascularization. We used Cox regression to evaluate death and repeat revascularization within one year and logistic regression to evaluate SNF use and 30-day readmissions/death. Results: CABG patients were 25.1 percentage points [95% confidence interval: 24.7, 25.5] more likely to use SNF following revascularization than inpatient PCI patients. SNF use was associated with a higher death rate (hazard ratio (HR): 3.19 [3.02, 3.37]) and a 16.2 percentage point (15.5, 16.9) increase in 30-day readmissions/death. Among patients with SNF use, CABG was associated with a decrease in 30-day readmissions/death compared to PCI. Conclusions: While CABG was associated with higher rates of SNF use and 30-day readmission/death overall, CABG was associated with significantly lower rates of 30-day readmissions/death among patients with SNF use. The findings suggest that caution is needed in treatment selection for patients at high-risk for SNF use and that selection of inpatient PCI over CABG may be associated with frailty and worse outcomes for some patients.