Short-term outcome of patients with possible transient ischemic attacks: a prospective study

Patients with transient ischemic attack (TIA) have an increased risk of vascular events. There is scarce data regarding the prognosis of patients with transient neurological symptoms less typical of TIA, in whom a vascular origin cannot be excluded, also known as possible TIA. In this study we aimed to compare the short-term prognosis between TIA and Possible TIA patients.

Patients with transient neurological events consecutively referred to a TIA Clinic during five years were classified as TIA, Possible TIA or mimic. Patients were prospectively followed. We compared the outcome at 30 and 90 days after TIA or Possible TIA. The primary outcome was stroke and the secondary outcome was a combination of vascular events (stroke, TIA, myocardial infarction or vascular death).

Two hundred and fifty eight TIA and 109 Possible TIA patients were included. Possible TIA patients had no stroke 30 and 90 days after the event. In contrast, 3.1 % and 4 % of TIA patients had stroke at the same time points. Combined vascular events occurred in 1.9 % of Possible TIA (myocardial infarction) and 9.8 % of TIA patients (stroke and TIA) after 30 days (OR = 0.18, 95 % CI 0.04 to 0.76, P = 0.02); and in 1.9 % of Possible TIA patients (myocardial infarction) and 11.3 % of TIA patients (stroke and TIA) after 90 days (OR = 0.16, 95 % CI 0.04 to 0.67, P = 0.012).

In this exploratory study, Possible TIA patients had less short-term vascular events than TIA patients.