Transient global amnesia: clinical features and prognostic factors suggesting recurrence

Abstract

The risk of recurrence of new amnesia events in patients having previously experienced transient global amnesia (TGA) ranges between 2.9-23.8%. Objective: Our objective was to search for recurrence predictors in TGA patients. Methods: Retrospective analysis to identify recurrence predictors in a cohort of 203 TGA patients from a single center in Buenos Aires, Argentina, diagnosed between January 2011 and March 2017 Clinical features and complementary studies (laboratory results, jugular vein Doppler ultrasound and brain MRI) were analyzed. Comparison between patients with recurrent versus single episode TGA was performed, applying a multivariate logistic regression model. Results: Mean age at presentation was 65 years (20-84); 52% were female. Median time elapsed between symptom onset and ER visit was two hours, with the average episode duration lasting four hours. Mean follow-up was 22 months. Sixty-six percent of patients referred to an identifiable trigger. Jugular reflux was present in 66% of patients; and 22% showed images with hippocampus restriction on diffusion-weighted MRI. Eight percent of patients had TGA recurrence. Patients with recurrent TGA had a more frequent history of migraine than patients without recurrence (37.5% vs. 14%; p = 0.03). None of the other clinical characteristics and complementary studies were predictors of increased risk of recurrence. Conclusions: Patients with migraine may have a higher risk of recurrent TGA. None of the other clinical characteristics evaluated allowed us to predict an increased risk of recurrence. Although the complementary studies allowed us to guide the diagnosis, they did not appear to have a significant impact on the prediction of recurrence risk.

Transient global amnesia: an intriguing yet benign disturbance

“…Of note, this difference was statistically significant but, by looking at the actual figures (migraine was present in 37.5% of patients with recurrence and in 14% of those without recurrence), one can recognize that this factor did not play a crucial role in pathogenic terms, being present in only one-third of patients with recurrent TGA. None of the other many clinical characteristics and complementary studies looked at, including MRI and venous Doppler studies, were predictors of an increased risk of recurrence 1 .…”

“…Overall, about one-quarter of TGA patients will experience a second attack in their lifetime, with very few experiencing more than two 3 . The authors found that patients with recurrent TGA more frequently had a history of migraine than TGA patients without recurrence 1 . Of note, this difference was statistically significant but, by looking at the actual figures (migraine was present in 37.5% of patients with recurrence and in 14% of those without recurrence), one can recognize that this factor did not play a crucial role in pathogenic terms, being present in only one-third of patients with recurrent TGA.…”

“…T he paper by Alessandro et al, published in this issue of Arquivos de Neuro-Psiquiatria 1 , reports on the results of a study aimed at identifying possible predictors of episode recurrence in a group of 203 transient global amnesia (TGA) patients seen in one center over a relatively short time period. As in previous studies, only a minority of patients had a recurrence over the two-year follow up; the low rate of recurrence (8%) was comparable to that reported in other studies with longer follow ups 2 .…”

“…The association of some TGA episodes with Valsalva-like maneuvers has more recently generated a fourth hypothesis, i.e., a role for internal jugular valve insufficiency 8 , but this hypothesis has also not been confirmed 9. A large number of studies, such as the one by Alessandro et al 1 , have reported a remarkable temporal association between TGA episodes and what have been defined as precipitating events, such as exertion, hot or cold baths, quarrels, and Valsalva-like maneuvers such as coughing. Most surprising is the occurrence of a considerable number of TGA episodes soon after sexual intercourse.…”

For how long is memory lost in transient global amnesia?

“…Although transient global amnesia (TGA) was first described more than 50 years ago , the disorder still has several unrevealed aspects, particularly related to its pathophysiology. Three main pathophysiological mechanisms have been proposed to account for the clinical syndrome of TGA, namely transient ischaemic attacks, venous congestion and migraine . Psychogenic factors, such as emotionally stressful situations and phobic personality traits, are also associated with TGA .…”