Protocol of the Stroke in Korean Young Adults Study: A Multicenter Case-Control Study and Prospective Cohort Study

BackgroundThe incidence of ischemic stroke in young adults has been rising over recent decades, but there is still limited information on its risk factors, etiologies, and outcomes. Because these patients generally participate in social life, risk factors associated with lifestyle may have a great impact and need to be identified.MethodsThe SKY (Stroke in Korean Young Adults) study is a multicenter case-control study and a prospective cohort study in 8 tertiary medical centers in the Republic of Korea. The case subjects are patients aged 18-44 years with first-ever ischemic stroke occurring within 1 month of stroke onset, and the control subjects are age- and gender-matched community controls. Our aim is to include 470 cases and 470 controls. The main objective of our study is to determine the risk factors and the causes of ischemic stroke in Korean young adults. Both well-documented risk factors and little-known lifestyle-related risk factors such as lifestyle habits and psychological distress including job strain will be evaluated by comparing cases and controls using a structured questionnaire. Secondary objectives are to determine the risks of mortality, recurrent vascular events, and poststroke epilepsy in these patients. Conditional logistic regression analysis will be used to estimate odds ratios and 95% confidence intervals.ConclusionsThe SKY study is designed to obtain more insights into relatively little-known risk factors in young Korean adults with ischemic stroke. The results may also help identify the frequencies of uncommon etiologies and outcomes in these patients.