RISK FACTORS AND ETIOLOGY OF TRANSIENT ISCHEMIC ATTACKS IN PATIENTS WITH BRAIN INFARCTION

  Abstract INTRODUCTION: Transient ischemic attacks (TIA) are warnings of future stroke. There is no difference in risk factors, pathophysiology and prevention between TIA and brain infarction. methods: Consecutive patients with brain infarction admitted to Ghaem Hospital, Mashhad, Northeastern Iran, were enrolled in a prospective study during ۲۰۰۶. Diagnosis of ischemic stroke was established by a neurologist who also obtained history of TIA and vascular risk factors. All of the stroke patients underwent a standard battery of diagnostic investigations and etiology of ischemic stroke was determined by the Practical Iranian Criteria classification. Fisher’s exact test was used for statistical analysis. results: ۳۴۸ stroke patients (۱۸۶ women, ۱۶۲ men) were studied. History of TIA was present in ۴۲ patients (۲۹ women, ۱۳ men), i.e. ۱۲% of the stroke patients. TIA was more common in women (df=۱, P=۰.۰۲). The frequency of hypertension, diabetes and ipsilateral carotid stenosis was not significantly different between patients with history of TIA and other stroke patients (P=۰.۸۷, P=۰.۶۴ and P=۰.۶۱, respectively). Hyper-cholesterolemia and smoking were significantly more frequent in stroke patients with history of TIA (P=۰.۰۱۱ and P=۰.۰۱۴, respectively). The frequency of TIA was not significantly different among patients with lacunar, versus large vessel territory infarcts (df=۱, P=۰.۸۴). There was no significant difference in the frequency of various stroke etiologies in patients with and without history of TIA (df=۴, P=۰.۶۱). CONCLUSIONS: Stroke patients with history of TIA have vascular risk factors similar to other stroke patients. A positive history of TIA does not affirm any specific etiology of ischemic stroke.     Keywords: Risk factors, etiology, transient ischemic attacks.