Distribution of etiologies in patients above and below age 45 with first-ever ischemic stroke.

BACKGROUND: There is limited information about distribution of etiologies of ischemic stroke in different age groups.
MATERIALS AND METHODS: In this study, we applied the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification in 87 patients aged < or = 45, and in 347 patients aged 46-60 years with first-ever ischemic stroke in order to follow the distribution of stroke etiologies in different age groups.
RESULTS: Traditional risk factors, except smoking and atrial fibrillation, were more frequent in older patients. The most frequent etiologies in the younger stroke patients (aged < or = 45) were 'other' than routine causes (26.4%), cardioembolism (22.4%) and 'idiopathic' strokes (20.7%), when no cause was found. In older patients (aged 46-60), small vessel disease (25.1%) and cardioembolism (22.2%) were the most frequent etiologies of stroke.
CONCLUSIONS: In stroke patients below the age of 45, the TOAST classification should be expanded to better classify the wide diversity of stroke etiologies. The relatively low frequency of routine stroke etiologies in patients aged < or = 45 can be explained by the significantly lower prevalence of traditional risk factors in these patients. In patients 46-60 years old, the TOAST classification is adequate in the characterization of ischemic stroke etiologies.