Background: Poorer socioeconomic status (SES) is associated with higher stroke incidence. Less is known about SES and stroke recurrence. We sought to obtain updated estimates of stroke incidence stratified by aggregate measures of SES, and to explore the association between SES and stroke recurrence. Methods: The Greater Cincinnati/Northern Kentucky region includes a population of 1.3 million, representative of the US population in terms of sociodemographics and percent black race. We ascertained all hospitalized strokes in the region in 2015 by screening ICD-9 codes 430-437 and ICD-10 codes I60-69, G45-46. Recurrent strokes were ascertained from 1/1/2015-12/31/2018. Patients’ home addresses were geocoded using DeGAUSS. Population estimates were obtained from the US Census Bureau using the 2015 5-year American Community Survey. Aggregate SES was estimated by percentage below poverty in each census tract. Regional incidence and recurrence rates were adjusted for age, sex, and race and calculated both with and without SES adjustment using Poisson regression models. Results: Stroke incidence and recurrence rates stratified by SES are shown in the Table. Poorer SES was associated with greater stroke incidence (p<0.01) and recurrence (p<0.01) across races. The relative risk (95% CI) for first-ever stroke among black compared with nonblack individuals was 2.06 (1.79-2.38) before adjusting for SES, and 1.79 (1.54-2.08) after adjusting for SES. The relative risk (95% CI) for recurrent stroke among black compared with nonblack individuals was 2.54 (1.91-3.37) before adjusting for SES, and 2.00 (1.47-2.74) after adjusting for SES. There was no race by SES interaction. Conclusions: Poorer SES was associated with increased risk for both incident and recurrent stroke across races. Of the excess risk for stroke incidence among black individuals, 25.5% was accounted for by SES, while 35.1% of the excess risk for recurrence was accounted for by SES.
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