Formal Education, Socioeconomic Status, and the Severity of Aphasia After Stroke

Objective: To determine the role of education and socioeconomic status on the severity of aphasia after stroke. Design: Cross-sectional study. Setting: Stroke units of 2 affiliated medical centers. Participants: Stroke patients (n=173) within 24 hours of symptom development and hospitalized controls (n=62) matched for age, education, and socioeconomic status (SES) with normative brain magnetic resonance imaging. Interventions: Not applicable. Main Outcome Measures: Percent error on 9 language tasks (auditory and written comprehension, naming [oral, written, and tactile], oral reading, oral spelling, written spelling, and repetition). Education was recorded in years and dichotomized as less than 12 years or 12 years and above for data analysis. Demographic characteristics (age, sex, race) and stroke volume were recorded for adjustment. SES was obtained from census tract data as 2 variables: mean neighborhood household income and family income. Results: The percentage of errors for participants with 12 or more years of education was significantly lower for auditory and written comprehension, written naming, oral reading, oral spelling, and written spelling of fifth grade vocabulary words, even after adjusting for age, sex, stroke volume, and SES. Conclusions: These findings suggest that even once learned, access to written word forms may become less vulnerable to disruption by stroke with increasing years of education.