We performed a retrospective cohort study of AIS patients aged 19-49 discharged from two Bronx-based academic teaching hospitals from 2013 to 2018. Strokes were subtyped using the TOAST criteria. ANOVA and Mann-Whitney U-tests were used to determine age differences and chi-squared analysis was used to determine differences in subtype.

In the 451 patients that met inclusion criteria, mean age was 41.1 years and 48.2% were woman. We found no differences in subtype by race or ethnicity. In addition, though the median age of AIS was similar by race, it was significantly lower in Hispanic compared to non-Hispanic patients (median_Hispanic = 42; median_non-Hispanic = 45; p = 0.024). Finally, the median ages of patients with cardioembolic (CE), cryptogenic and other subtypes were significantly lower than the median ages of patients with lacunar and large artery atherosclerosis (LAA) subtypes (median_CE = 41yrs; median_cryptogenic = 43 yrs; median_other = 40 yrs; median_lacunar = 47 yrs; median_LAA = 47 yrs; ** p<0.01; *** p<0.001; **** p<0.0001).

The proportion of AIS subtypes in a diverse urban cohort aged 19-49 did not vary by race or ethnicity. Patients with CE and cryptogenic stroke subtypes were significantly younger than those with lacunar and LAA subtypes. More exploration of subtype-specific risk factors is needed to understand drivers of stroke in the young.