Trends and Racial Differences in First Hospitalization for Stroke and 30-Day Mortality in the US Medicare Population From 1988 to 2013.

Abstract

The main purpose of this study was to determine whether there were temporal differences in the rates of first stroke hospitalizations and 30-day mortality after stroke between black and white Medicare enrollees. We used a 20% sample of Medicare beneficiaries aged 65 years or older and described the annual rate of first hospitalization for ischemic and hemorrhagic strokes from years 1988 to 2013, as well as 30-day mortality after stroke hospitalization. We used linear tests of trend to determine whether stroke rates changed over time, and tested the interaction term between race and year to determine whether trends differed by race. We identified 1,009,057 incident hospitalizations for ischemic strokes and 147,817 for hemorrhagic strokes. Annual stroke hospitalizations decreased significantly over time for both blacks and whites, and in both stroke subtypes (P-values for all trend <0.001). Reductions in stroke rates were comparable between blacks and whites: among men, the odds ratio for the interaction term for race by year was 1.008 [95% confidence interval (CI), 1.004-1.012] for ischemic and 1.002 (95% CI, 0.999-1.004) for hemorrhagic; for women, it was 1.000 (95% CI, 0.997-1.004) for ischemic and 1.003 (95% CI, 1.001-1.006) for hemorrhagic. Both black men and women experienced greater improvements over time in terms of 30-day mortality after strokes. Rates of incident hospitalizations for ischemic and hemorrhagic strokes fell significantly over a 25-year period for both black and white Medicare enrollees. Black men and women experienced greater improvements in 30-day mortality after both ischemic and hemorrhagic stroke.