Secular Trends for Etiologies of Acute Ischemic Stroke in Young Adults

Background Ischemic stroke is not rare among young adults. Understanding secular trends in the mechanism of ischemic stroke in young adults may help guide evaluation and secondary prevention. This study compares the mechanism of ischemic stroke and diagnostic studies in two groups of young adults treated at the University of Iowa 20 years apart. Methods We retrospectively reviewed all patients aged 15-45 who presented to the University of Iowa Hospitals between 1/2010-11/2016 with ischemic stroke confirmed by imaging. Diagnostic studies and stroke etiologies for each patient using the TOAST criteria were reviewed and compared to a historic sample of young patients of the same age who presented to our center in 1977-1993. Results We identified 322 young adults, 165 (51.2%) were women. The mean age was 36.3 ± 7.2 years. Vessel imaging was performed in 317 (95.2%) cases vs. 68.9% in the historic sample. Of these, 259 (80.4%) had magnetic resonance angiography (MRA), while diagnostic angiogram was the sole modality used for vessel imaging in the historic sample. Transthoracic echocardiography (TTE) was performed in 101 (31.4%) and transesophageal echocardiography (TEE) was performed in 169 (52.5%) cases compared to 67.1% who underwent TTE in the historic sample. In comparison with the historic sample, there was a significant decline in strokes due to small vessel disease [odds ratio (OR) 0.49, 95% confidence intervals (CI) 0.25-0.97]. The most common etiology of stroke in our sample was cervical artery dissection in 79 (24.5%) patients, whereas this was found in only 6.0% of patients in the historic sample [OR 5.0 and CI (2.99-8.44). Conclusions Using the TOAST classification, cryptogenic stroke remained the most common subtype in young adults. While the most common cause for ischemic stroke was cervical artery dissection. Disclosures Enrique Leira receive salary support from the National Institute of Health.