Supplementary Material for: Rural-Urban Disparities in Acute Stroke Treatments and Outcomes: A Propensity Score-Matched Analysis of a Nationwide Sample.

Purpose
To investigate the rural-urban differences in acute stroke care in a large cohort of patients hospitalized for acute ischemic stroke (AIS), using a nationwide inpatient sample.

Methods
In this retrospective cohort study, the National Inpatient Sample database was investigated for patients admitted with AIS from 2016 to 2022. Socio-demographics and comorbidities were reviewed. Interventions (rtPA and thrombectomy) were investigated. Outcome measures were prolonged length of stay (PLOS) and mortality. PLOS was defined as length of stay exceeding the 75th percentile of the entire cohort. The cohort was divided in rural and urban location Propensity-score matching (PSM) was applied to balance demographics and comorbidities between the two groups, and outcomes were analyzed between the two matched groups. Multivariable logistic models were used to determine the association between each intervention and rural location. Risk ratio was calculated for PLOS and mortality. Subgroup analyses were performed by age, race, and income. P value as set at 0.05 for all analyses.

Results
Of 897,206 AIS patients, 64,640 (7.2%) were cared for in rural location. Rural group was older (74 [64-83] vs. 71 [60-81], p<0.01) years. Rural group had higher rate of females (51.8% vs. 49%), white racial group (79.8% vs. 64.5%), lower median household income (54.3% vs. 29.1%), and lower private insurance (14.3% vs. 19.2%), p<0.01 for all. After PSM 1:1, rural group independently retained lower odds of rtPA (OR: 0.532, 95%CI: 0.505 - 0.561), lower odds of thrombectomy (OR: 0.074, 95%CI: 0.061 – 0.089), lower risk of PLOS (RR: 0.887, 95%CI: 0.882 – 0.892) and higher risk of mortality (RR: 1.149, 95%CI: 1.122 – 1.177), p<0.01 for all. Older patients in rural setting had lowest odds of interventions, whereas younger, Black, and Hispanic rural patients had highest risk of mortality after AIS.

Conclusions
Socio-demographic differences are present between rural and urban acute stroke care. Profound inequalities exist in the use of reperfusion therapy and outcomes. Great effort is needed by the stroke community to fill this gap and provide equality in acute stroke care.