Abstract W P308: Racial Disparities in IV rt-PA Use Persist at Primary Stroke Centers

Abstract

Background: Primary Stroke Centers (PSCs) utilize more recombinant tissue plasminogen activator (rt-PA) than non-PSCs. The impact of PSCs on racial and ethnic disparities in rt-PA usage is unknown. We sought to evaluate for differential access to PSCs and disparities in rt-PA use using an administrative database. Methods: The Nationwide Inpatient Sample was used from 2004-2010, limited to states that publicly reported both hospital identity and race/ethnicity. Patients ≥18 years with a primary ICD9 diagnosis of ischemic stroke (433.x1, 434.x1, 436) were included. Data from The Joint Commission was used to identify PSCs and determine if evaluating hospitals were certified at admission. Rt-PA was defined by ICD9 code 99.10. Multivariable models were constructed, additionally adjusting for year, age, sex, insurance, medical comorbidities, a DRG-based mortality risk indicator, ZIP code median income, and hospital characteristics. Results: Data from 26 states met eligibility criteria, including 304,152 discharges of which there were 71.5% White, 15.0% Black, 7.9% Hispanic, and 5.6% Other (Asian/Pacific Islander, Native American, or other). Overall, 24.7% of White, 27.4% of Black, 16.2% of Hispanic, and 29.8% of Other patients presented to PSCs. A higher proportion received rt-PA at PSCs than non-PSCs in all racial/ethnic groups (White 7.6% vs 2.6%, Black 4.8% vs 2.0%, Hispanic 7.1% vs 2.4%, Other 7.2% vs 2.5%). In the fully adjusted model Blacks were less likely to receive rt-PA than Whites at non-PSCs (OR=0.58, 95% CI 0.50-0.67) and PSCs (OR=0.63, 95% CI 0.54-0.74). This disparity was consistent across all subgroups (Figure 1). Conclusions: Black patients were less likely to receive rt-PA than White patients at both non-PSCs and PSCs. Relatively fewer Hispanic patients were evaluated at PSCs, though they received rt-PA at a rate similar to White patients. More research is necessary to understand the patient and provider factors underlying these disparities.