Abstract 2691: Multicenter, International Study of Stroke in the Young (MISSY): Initial Results on Racial Disparities in Early Outcomes

Abstract

Background&Purpose: Strokes in young adults differ from cerebrovascular events in the general population due to a wider variety of etiopathogenic mechanisms as well as by incidence and outcomes. Limited data exist regarding racial disparities in stroke outcomes in this specific age subgroup. We sought to prospectively evaluate potential racial disparities in early outcomes of young individuals with stroke in a multicenter, international study. Subjects&Methods: We prospectively evaluated consecutive first-ever stroke patients aged 18-45 years old who were admitted in 7 tertiary care stroke centers in North America (n=2), Europe (n=3) and Asia (n=2) over a four-year period (2008-2011). Demographics, vascular risk factors, etiopathogenic mechanism of stroke and stroke severity at hospital admission (assessed using the NIHSS-score) were documented. Early functional outcome at 1 month following stroke onset was evaluated using modified Rankin Scale (mRS) score. Results: A total of 826 young adults (mean age 37±7years; 60% men; 49% Caucasians, 19% African-Americans and 32% Asians; median baseline NIHSS-score 6 points, interquartile range 3-14) have been evaluated during the study period with first-ever ischemic (84%) or hemorrhagic (16%) stroke. Baseline stroke severity differed between Caucasians (median NIHSS-score 4 points, interquartile range 2-10), African-Americans (median NIHSS-score 7 points, interquartile range 3-15) and Asians (median NIHSS-score 9 points, interquartile range 5-14; p<0.0001 by Kruskal-Wallis test). Early favorable functional outcome (defined as a 30-day mRS-score of 0-1) was different among racial subgroups (59% in Caucasians, 38% in African-Americans and 36% in Asians; p<0.0001). Race was independently (p=0.017) associated with functional outcome in multivariate logistic regression models adjusting for age, gender, vascular risk factors, baseline stroke severity and stroke subtype. Asian young adults with stroke were less likely to achieve an early favorable outcome (OR: 0.42, 95%CI: 0.22-0.79; p=0.008) compared to Caucasians. The former association was not significant for African-Americans (OR: 0.93, 95%CI: 0.55-1.55; p=0.767) compared to Caucasians. Conclusions: Racial disparities in early functional outcome following first-ever stroke in young individuals appear to be independent of other known outcome predictor variables. Asian young adults with stroke tend to have a lower likelihood to achieve functional independence at 30 days following stroke onset. The underlying mechanisms of the former association deserve further investigation.