Epidemiology

Epidemiological data put the annual incidence of TGA between 3.4 and 10.4/100,000 (1)

• most commonly presents in the seventh decade of life. Across studies, the mean age of an episode ranges from 61 to 67.3 years
• studies show a slight female predominance (1,2)
• study evidence showed a recurrence rate of recurrence rate of 6.3% in a 10 year period

Precipitating events (3):

• A study of 142 cases of TGA found precipitating factors in 131 of these episodes (89.11%)
  • emotional stress (ie, triggered by gastric endoscopy, birth/death announcement, and difficult/exhausting work day), physical effort (ie, gardening, house work, and sawing wood), and water contact/temperature change (ie, hot bath/shower and cold swim) were observed most frequently immediately before an attack and are considered "close events"
  • anxiety triggered by conflict at home or work, health problems, and financial stressors were often reported weeks prior to TGA and are considered "remote events"
  • percentage of emotional stress, physical effort, and water contact/temperature change was 29, 25, and 14%, respectively, compared to 48, 9, and 0% in control groups, respectively

Reference:

• Owen D et al. Classical diseases revisited: transient global amnesia. Postgrad Med J. 2007 Apr; 83(978): 236-239.
• Spiegel DR et al. Transient global amnesia: current perspectives.Neuropsychiatr Dis Treat. 2017; 13: 2691-2703.
• Quinette P, Guillery-Girard B, Dayan J, et al. What does transient global amnesia really mean? Review of the literature and thorough study of 142 cases. Brain. 2006;129(pt 7):1640-1658