Racial Disparities in Longitudinal Functional Outcome after Ischemic Stroke
TL;DR
AIS functional outcomes are worse among Black individuals starting at discharge and persisting out to 12 months, significantly attenuated by clinical factors and social determinants; future studies should explore whether the social determinants can be intervened upon in the recovery period.
Abstract
Background: The burden of stroke is unequally distributed in the US, with Black individuals experiencing more incident stroke. It remains unclear whether Black individuals also experience worse stroke recovery. We sought to study disparities in longitudinal functional outcome after acute ischemic stroke (AIS) in a population-based study. Methods: We conducted a retrospective cohort study in the Greater Cincinnati Northern Kentucky region over an 18-month period (7/2019–12/2020). All AIS events were captured. Modified Rankin Scale (mRS) scores were determined at discharge, 3, 6, and 12 months for patients who survived the index event. We studied the association between Black race and longitudinal mRS (across all timepoints) with mixed effects ordinal regression, initially adjusting for age, sex, and time since stroke. Hierarchical regression was used to sequentially adjust for stroke severity/management, premorbid health, and social determinants. Results: Among 2796 patients with AIS (mean age 69.0, 31% Black, 52% female), 2537 survived and were included (mean age 68.4, 32% Black, 52% female). Black race was associated with a worse longitudinal mRS (cOR 2.61, 95% CI 1.89–3.60). Excluding patients with recurrent events did not change this association (cOR 2.69, 95% CI 1.92–3.78). Adding variables reflecting initial stroke severity/management partly attenuated the association (cOR of 1.92 with a 95% CI of 1.43–2.60). Adding variables reflecting premorbid health further attenuated the association (cOR decreased to 1.43 with 95% CI 1.09–1.87). The remaining association between Black race and mRS was fully attenuated by social determinants, with cOR 1.09 (95% CI 0.80–1.47). There was no interaction between race and time since stroke. Conclusion: Starting at discharge and persisting out to 12 months, AIS functional outcomes are worse among Black individuals. These disparities are significantly attenuated by clinical factors and social determinants; future studies should explore whether the social determinants can be intervened upon in the recovery period.