Transient ischaemic attacks in young patients: a thromboembolic or migrainous manifestation? A 10 year follow up study of 46 patients. Forty six patients aged 18-39 years with transient ischaemic attacks (TIA) were studied; two thirds were women. Twenty five patients had attacks accompanied by headache, and seven gave a history of common migraine. Only four of 27 angiograms were abnormal; no operable carotid lesion was demonstrated. Over a mean follow up period of 10 years stroke or myocardial infarction (AMI) occurred in all four patients who presented major cerebrovascular risk factors, but in only two of the remaining 42 patients. Thus irrespective of age thromboembolic TIA is a harbinger of stroke or AMI. However, most TIAs under the age of 40 years are caused by a non-embolic benign vascular disorder. The clinical characteristics, long-term prognosis, and possible pathogenesis, for such attacks are often indistinguishable from those of classical migraine. In the absence of cardiovascular risk factors, arteriography does not provide much diagnostic and prognostic information. 