Abstract Body: Background:
Non-Hispanic Black (NHB) and other minority patients in the United States (US) receive intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) less frequently compared with non-Hispanic White (NHW) patients during acute ischemic stroke (AIS) admission. It remains uncertain how the interaction between race and the income category of patients influences treatment and outcome.
Methods
We identified all primary AIS hospitalizations in the 2006-2021 National Inpatient Sample (NIS) receiving IVT and MT using International Classification of Diseases (ICD) codes. Admissions were categorized into income quartiles (Q1-Q4) using the median household income of the patient’s zip code. Multivariable logistic regression models adjusted for age, sex, clinical and hospitalization factors were used to compare odds of IVT, MT, in-hospital mortality and good outcome (defined as routine home discharge) between race and income groups.
Results
Of 7,476,163 weighted AIS hospitalizations from 2006-2021, 31.1% were in the lowest (Q1) and 19.4% in the highest (Q4) income quartile. 9.3 % of admissions received IVT and 2.7% received MT across the study period. Utilization of both procedures increased in all income groups over time but usage was persistently lower in Q1 admissions compared to Q4 (figure 1). In multivariable-adjusted models restricted to 2015-2021, all minority racial groups including NHB admissions had lower odds of IVT (OR 0.74, 95%CI 0.72-0.76) and MT (OR 0.74, 95%CI 0.71-0.77) vs NHW. Q1, Q2 and Q3 admissions had lower odds of IVT compared to Q4 and Q1 admissions had lower MT odds (OR 0.92, 95%CI 0.90-0.95) vs Q4. Further stratification by income and race, showed that IVT and MT odds increased with income for NHW admissions but notably all quartiles of NHB admissions including Q4 had up to 20% lower odds of IVT and MT compared to Q1 of NHW admissions (Figures 2a and 2c). Among NHB and NHW admissions, odd of in-hospital mortality was significantly lower in Q4 vs Q1, while odds of good outcome was greater in Q4 vs Q1 income categories, but these differences were not consistently seen in Hispanic and Asian hospitalizations (Figure 3).
Conclusion
Racial disparities in IVT and MT use in the US is not explained by income alone. NHB individuals in all income categories receive IVT and MT at rates less than the lowest income category of NHW individuals. Q1 admissions have higher mortality and lower odds of good outcome compared to Q4 admissions.