The long-term prognosis of Transient Global Amnesia: a systematic review

Abstract

Transient Global Amnesia (TGA) constitutes an enigmatic amnestic condition. In view of the admittedly limited knowledge regarding the nature of TGA, we decided to systematically review existing evidence for the generally regarded benign course of the disease. MEDLINE, EMBASE, CENTRAL and PsycINFO were searched for relevant articles. Observational (case-control, cross-sectional and cohort) controlled studies were retrieved. TGA diagnosis was made according to the diagnostic criteria of Caplan, validated by Hodges and Warlow. The TGA group was compared with either healthy controls (HC) or/and individuals with transient ischaemic attacks (TIA). The long-term risks of dementia, epilepsy, psychological-emotional disturbances, as well as long-term vascular and (vascular or nonvascular) mortality risks, were evaluated. Quality assessment was based on the Newcastle–Ottawa Scale. Literature search provided 12 eligible articles. Retrospective, prospective or mixed cohort designs were implemented in every study. Five articles registered a high quality, five registered a moderate quality, while two articles were assessed as part of the grey literature (conference abstract, abstract in English-article in Spanish). Overall, retrieved evidence was suggestive of similar vascular and mortality risks in TGA patients and HC, while TIA individuals exhibited elevated risks. Moreover, psychological disturbances were comparable between TGA and healthy individuals. On the other hand, studies for dementia and epilepsy obtained contradictory results, indicating both a similar and an increased risk in the TGA group compared to the HC group. Therefore, additional high-quality studies are warranted for the acquisition of more determining conclusions regarding the long-term risk of dementia and epilepsy in TGA.

Transient Global Amnesia (TGA): Sex-Specific Differences in Blood Pressure and Cerebral Microangiopathy in Patients with TGA

“…This correlated to less severe cerebral microangiopathy and less septal hypertrophy in transthoracic echocardiography. These observations are supported by evidence of a lower vascular mortality risk in TGA patients compared to TIA patients [ 37 ]. We hypothesised that acute hypertensive peaks may trigger TGA episodes, especially in patients not adapted to chronic hypertension [ 21 ].…”

Transient Global Amnesia (TGA): Younger Age and Absence of Cerebral Microangiopathy Are Potentially Predisposing Factors for TGA Recurrence

“…TGA patients showed a lower extent of cerebral microangiopathy and less frequent septal hypertrophy in transthoracic echocardiography compared with stroke patients, thus presenting less sequelae of hypertensive heart and brain damage. These observations were supported by a recent review with evidence of similar vascular and mortality risk in TGA patients compared to healthy controls, whereas TIA patients have an increased risk ( 11 ).…”

“…This was reflected by lower levels of consecutive hypertensive disorders, such as the extent of cerebral microangiopathy and septal hypertrophy in transthoracic echocardiography. These observations are substantiated by evidence of a lower vascular mortality risk in TGA patients compared with TIA patients (11). It was hypothesized that acute hypertensive peaks may trigger TGA episodes, especially in patients who are not adapted to chronic hypertension (10).…”

Glymphatic System Function in Patients with Transient Global Amnesia

“…A previous systematic review, which assessed the long-term prognosis of TGA, found a benign prognosis with respect to the vascular sequelae, but a lack of relevant evidence supporting an overall favorable prognosis, especially when considering the outcomes of dementia and epilepsy. Further researches are needed [38]. The second possibility is that although there could be glymphatic system dysfunction in patients with TGA, our study failed to find it.…”