FACTS CLINICAL What you need to know about... TRANSIENT GLOBAL AMNESIA There is no treatment for the spontaneously occurring disorder TGA Alamy WHAT IS IT? CAUSES SYMPTOMS DIFFERENTIAL DIAGNOSIS ● Transient global amnesia (TGA) is Precipitating factors include: A patient with TGA: ● Toxin-induced memory loss tends a temporary and isolated disorder of ● Sexual intercourse; ● Is acutely confused; to include inattention and an the memory. ● Heavy physical exercise (usually ● Is neurologically intact except for inability to sustain coherent thought. ● An episode of this disorder swimming in cold water); absent memory (for example, ● In complex partial seizures, consists of a loss of recent and ● There is a small correlation remains alert, remembers identity, repetitive questioning is not a feature. new memories. between TGA and patients who remembers past experiences); ● Psychogenic amnesia tends to ● An episode of TGA usually suffer from migraines, epileptic fits, ● Asks relevant questions repeatedly occur at a younger age and the occurs spontaneously. and cerebrovascular disease; because she or he does not patient is more likely to have ● The syndrome is largely benign ● Physical or emotional stress; remember the answer; personality changes and not in nature due to the fact that the ● Driving a car. ● Is unable to recall the episode remember personal details. episode is temporary. once she or he has recovered; ● The patient is usually otherwise PATHOPHYSIOLOGY ● Usually maintains her or his REFERENCES healthy and middle aged or older. ● The precise pathophysiology of semantic memory (long-term Hodges, J., Simons, J. (2000) ● An attack may last several hours. TGA is not clear. memory responsible for retaining Neurocase 2000. Volume 6. 211– ● Blood flow to specific brain areas knowledge about the world, including 230. Available from: HISTORY that involve memory including the the meaning of words and objects) www.icn.ucl.ac.uk/jsimons/pubs/ ● TGA was first described in 1956 thalamus and/or mesial temporal and meta memory (the awareness of ncasetga.pdf by Morris Bender. structures appears to be disrupted what one should know); ● Since then, TGA has become a transiently during TGA. ● Anterograde amnesia must Sucholeiki, R. (2004) Transient well-explained syndrome but its be present. Global Amnesia Emedicine. cause is still not totally understood. INCIDENCE Available from: www.emedicine.com/ ● TGA affects memory function. ● Three people per 100,000 of the TREATMENT NEURO/ Although many mechanisms have population per year are affected ● There is no treatment. topic380.htm been proposed, no single cause can with TGA. ● TGA is short-lived. fully explain all the features of TGA. ● The condition affects 50 per cent ● Patients with recurrent episodes WEBSITE ● Some authors have stated that more men than women. usually do not experience any Transient Global Amnesia (GP notes): patients with TGA have age and risk ● Less than 25 per cent of patients increased morbidity. www.gpnotebook.co.uk/cache/ factor profiles similar to those of experience repeated episodes. 1557135375.htm patients who experience stroke or ● Less than three per cent of patients transient ischaemic attack (TIA). experience three or more episodes. ● Permanent memory loss is rare. NT 6 July 2004 Vol 100 No 27 www.nursingtimes.net 33.