Risk Factors for Ischemic Stroke in Younger Adults

A Focused Update

Mary G. George, MD, MSPH, FACS


Stroke. 2020;51(3):729-735. 

In This Article

Abstract and Introduction


Ischemic stroke in younger adults is far less common than that among older adults, yet the underlying pathogeneses and risk factors are more diverse. Approximately 10% to 15% of all strokes occur in adults aged 18 to 50 years.[1–4] In part, because of this, the diagnosis of stroke in younger adults can be challenging to differentiate from stroke mimics and to identify the cause or underlying pathogenesis. The TOAST (Trial of ORG 10172 in Acute Stroke Treatment) classification system[5] (Table 1) is parsimonious, yet many younger stroke patients have pathogeneses that are more likely to fall under cardioembolism, other determined pathogenesis, or undetermined pathogenesis rather than large artery atherosclerosis or small-vessel occlusion.[1,6] Recent studies, both in the United States and Europe, have suggested that ischemic stroke in younger adults is increasing and have demonstrated increases in traditional stroke risk factors that are typically common among older adults (hypertension, dyslipidemia, diabetes mellitus, tobacco use, and obesity) to also be common among younger acute stroke patients.[1,7–13] Among younger adults presenting with acute stroke, in whom there has been an increasing prevalence of comorbid traditional cardiovascular disease risk factors, there is debate about whether or how much those traditional risk factors contribute to the cause of stroke,[4,14] particularly for those <40 years of age. This review examines some of the common and rarer pathogeneses of ischemic stroke in younger adults (Table 2).