Abstract TP333: Differential Trajectories of Mobility Recovery by Race in the Subacute Phase Post-Stroke

Introduction: Improved mobility is among the top targets for rehabilitation after stroke. However, little is known about the non-medical factors, including social determinants of health, that likely play an important role in mobility recovery post-stroke, as racial disparities in mobility arise in the weeks following discharge from acute care. We explored the impacts of race, insurance status, and area deprivation index (ADI, a neighborhood-level measure of socioeconomic disadvantage) on mobility outcomes over the first 90 days following acute care discharge in patients with first stroke. Hypothesis: We hypothesized that 1) race, insurance status, and ADI would interact to predict trajectories of mobility over time, as measured by the Activity Measure for Post-Acute Care (AM-PAC) mobility scores; and 2) Black patients with Medicaid would experience less improvement than White patients. Methods: We extracted data from patients seen for first stroke within the Johns Hopkins Medicine acute care hospital system. In addition to diagnosis, eligibility criteria included at least one AM-PAC mobility score within 48 hours of discharge and one 60-90 days after, and completeness of primary study variables. We ran linear mixed effects models using maximum likelihood estimation to assess the roles of race, insurance status, and ADI on AM-PAC mobility t-scores from acute care discharge and the following 90 days while controlling for age, sex, treating facility, length of stay, discharge location, marital status, employment status, and presence of relevant comorbidities. Results: Our study included 450 patients (age 65±15yrs; race: 53% White, 47% Black; sex: 53% male). Our best fit linear model included a random effect of patient and fixed effects of time, race, insurance status, ADI, and the interactions of these three variables with time (AIC=11854, BIC=12011). AM-PAC mobility scores generally improved over time (β=2.01points/month), and there was a significant race*time interaction (Black patients improving more than White patients, β=1.09, p=0.04). Conclusions: Black patients tended to improve more than White patients over the first 90 days following acute care discharge. This may be because they were significantly younger (mean=7yrs) than White patients. These findings warrant further study into the rehabilitation services provided by government-issued insurance and continued emphasis on early stroke prevention, especially within the Black community.