African American patients have a higher probability of cognitive impairment after incident stroke: An analysis of national electronic health record data

Background Cognitive impairment (CI) and stroke are diseases with significant disparities in race and geography. Post stroke cognitive impairment (PSCI) can be as high as 15-70% but few studies have utilized large administrative or electronic health records (EHR) to evaluate trends in PSCI. We utilized an EHR database to evaluate for disparities in PSCI in a large sample of patients after first recorded stroke to evaluate for disparities in race. Methods This is a retrospective cohort analysis of Cerner Health Facts® EHR database, which is comprised of EHR data from hundreds of hospitals/clinics in the US from 2009-2018. We evaluated patients ≥40 years of age with a first time ischemic stroke (IS) diagnosis for PSCI using ICD9/10 codes for both conditions. Patients with first stroke in the Cerner database and no pre-existing cognitive impairment were included, we compared hazard ratios for developing PSCI for patient characteristics Results A total of 150,142 IS patients with follow-up data and no pre-existing evidence of CI were evaluated. Traditional risk factors of age, female sex, kidney injury, hypertension, and hyperlipidemia were associated with PSCI. Only African American stroke survivors had a higher probability of developing PSCI compared to White survivors (HR 1.347, 95% CI (1.270, 1.428)) and this difference was most prominent in the South. Among those to develop PSCI, median time to documentation was 1.8 years in African American survivors. Conclusion In a large national database, African American stroke survivors had a higher probability of PSCI five years after stroke than White survivors.