Transient Ischemic Attacks in a Community

Sixty cases of transient cerebral ischemic attack (TIA) were noted during five years of observation of a large retirement community. The incidence of new cases was 1.1/1,000/yr and was 1.8 times greater in men than in women. Electrocardiographic abnormalities were associated with increased risk of TIA development; hypertension and cardiomegaly on chest roentgenograms were not. Most patients were not hospitalized for TIA. Forty-four patients with TIA and without previous cerebrovascular disease were followed up for an average of 27.4 months. Subsequent thromboses developed in eight (18%), confirming the prognosis of TIA reported from hospitals and neurologic clinics. The incidence of subsequent thrombosis was greatest during the first year after the initial TIA. Preliminary studies indicated that women, older patients, and those with attacks of less than one hour's duration were at increased risk of subsequent thrombosis.