In Italy, the public National Health System allows direct referral to the ED for any suspected TGA and, as a result, almost all suspected TGA cases were managed at ED or admitted as inpatients. Maria della Misericordia Hospital, Perugia between 20. The NU is a TGA registry including all patients diagnosed with TGA seen in the S. All cases were reviewed by the senior study neurologist (P.M.R.) and only patients with a final diagnosis of TGA from 1 April 2002 to 31 October 2018 were included in the current study. Daily searches of the local emergency department (ED) register and admissions to medical, stroke or neurology wards were also performed to ascertain cases that were admitted. As part of the study methods, all participating general practitioners were asked to refer any patient with suspected transient neurological attacks to the daily rapid‐access transient ischaemic attack/stroke clinic. The study methods have been reported previously 10. The current Oxford cohort (OXVASC) is an ongoing population‐based study of all incident and recurrent vascular events in a population of 92 728 individuals registered with 100 general practitioners in nine general practices in Oxfordshire, UK, which overlaps the general practice population of the Oxfordshire Community Stroke Project. Patients were followed up for a mean duration of 34.8 months 2. The original Oxford cohort consisted of 114 patients diagnosed with TGA either as part of the Oxfordshire Community Stroke Project or at the Department of Neurology in Oxford between 19.

We also extracted data from the original TGA cohort reported by Hodges and Warlow (Oxford cohort) 2. Both studies received ethical approval (OXVASC, OREC A−05/Q1604/70 NU, CEAS‐12976/18) and informed consent was provided.

We also aimed to study the frequency and prognosis of short‐duration TGA.Ĭonsecutive patients with first‐in‐study‐period suspected TGA were prospectively collected from OXVASC and NU. In the absence of any similar study, we aimed to determine whether there has been any evolution of the clinical spectrum of TGA in routine clinical practice since the original report by comparing the clinical features of TGA ascertained in two independent cohort studies in Oxfordshire, UK and by validating the results in another independent contemporary TGA cohort in Italy. Diagnostic certainty about TGA versus TEA will therefore partially depend on the frequency and prognosis of apparent short‐duration TGA cases among patients presenting with a transient amnestic syndrome. More importantly, TGA cases can potentially be of short duration with 9% of the TGA cases reported to be < 1 h in the original 1990 cohort report 1, 2. However, up to 30% of TGA cases also recur 1 and some TGA cases can also present with electroencephalography (EEG) changes 9.

TEA is reported as being shorter than TGA, lasting typically <1 h 4, 5, 6, 7, 8 with higher rates of recurrence over time 4. One diagnostic challenge of TGA is the exclusion of other potential causes of a transient amnestic syndrome, such as transient epileptic amnesia (TEA) 4. However, little is known about the evolution of clinical features of TGA since then. TGA was first reported in 1964 by Fisher and Adams 3 and the current clinical diagnostic criteria for TGA were proposed by Hodges and Warlow in 1990 2. Transient global amnesia (TGA) is characterized by sudden onset of anterograde amnesia lasting up to 24 h 1, 2.

Causes of transient epileptic amnesia