In-Hospital Outcomes of Percutaneous Coronary Intervention in America's Safety Net: Insights From the NCDR Cath-PCI Registry.

Objectives: This study compared risk-adjusted percutaneous coronary intervention (PCI) outcomes of safety-net hospitals (SNHs) and non-SNHs.

Background: Although risk adjustment is used to compare hospitals, SNHs treat a disproportionate share of uninsured and underinsured patients, who may have unmeasured risk factors, limited health care access, and poorer outcomes than patients treated at non-SNHs.

Methods: Using the National Cardiovascular Data Registry CathPCI Registry from 2009 to 2015, we analyzed 3,746,961 patients who underwent PCI at 282 SNHs (hospitals where ≥10% of PCI patients were uninsured) and 1,134 non-SNHs. The relationship between SNH status and risk-adjusted outcomes was assessed.

Results: SNHs were more likely to be lower volume, rural hospitals located in the southern states. Patients treated at SNHs were younger (63 vs. 65 years), more often nonwhite (17% vs. 12%), smokers (33% vs. 26%), and more likely to be admitted through the emergency department (48% vs. 38%) and to have an ST-segment elevation myocardial infarction (20% vs. 14%) than non-SNHs (all p < 0.001). Patients undergoing PCI at SNHs had higher risk-adjusted in-hospital mortality (odds ratio: 1.23; 95% confidence interval: 1.17 to 1.32; p < 0.001), although the absolute risk difference between groups was small (0.4%). Risk-adjusted bleeding (odds ratio: 1.05; 95% confidence interval: 1.00 to 1.12; p = 0.062) and acute kidney injury rates (odds ratio: 1.01; 95% confidence interval: 0.96 to 1.07; p = 0.51) were similar.

Conclusions: Despite treating a higher proportion of uninsured patients with more acute presentations, risk-adjusted PCI-related in-hospital mortality of SNHs is only marginally higher (4 additional deaths per 1,000 PCI cases) than non-SNHs, whereas risk-adjusted bleeding and acute kidney injury rates are comparable.