Michaela Rand, BA, MA Medical Student University of California, Irvine, School of Medicine Irvine, California
Angela Hu, MD PGY-2 Psychiatry Resident Department of Psychiatry & Human Behavior University of California, Irvine Irvine, California
Jody Rawles, MD Clinical Professor & Executive Vice Chair Department of Psychiatry & Human Behavior University of California, Irvine Irvine, California
Disclosures The authors report no financial relationships with any companies whose products are mentioned in this article, or with manufacturers of competing products.
Finally, patients with TGA are more likely to have psychiatric comorbidities than those without the condition. In a study of 25 patients who experienced TGA triggered by a precipitant, Inzitari et al4 found a strong association of TGA with phobic personality traits, including agoraphobia and simple phobic attitudes (ie, fear of traveling far from home or the sight of blood). Pantoni et al35 replicated these results in 2005 and found that in comparison to patients with TIA, patients with TGA are more likely to have personal and family histories of psychiatric disease. A 2014 study by Dohring et al36 found that compared to healthy controls, patients with TGA are more likely to have maladaptive coping strategies and stress responses. Patients with TGA tended to exhibit increased feelings of guilt, take more medication, and exhibit more anxiety compared to healthy controls.36
Treatment: Benzodiazepines
There are no published treatment guidelines for TGA. However, in case reports, benzodiazepines (specifically lorazepam37) have been shown to have utility in diagnosing and treating DA. The success of benzodiazepines is attributed to its gamma-aminobutyric acid mechanism, which involves inhibiting activity of the N-methyl-D-aspartate (NMDA) receptor, thereby reversing amnesia.37 The NMDA receptor is also implicated in the stress theory of TGA. Though TGA typically resolves on its own within 24 hours, given the distressing nature of this disorder, benzodiazepines may be a suitable option to hasten memory improvement, particularly in patients with psychiatric risk factors.
However, the benzodiazepine midazolam has been identified as a precipitant of TGA. In a case report, Rinehart et al22 identified flumazenil—a benzodiazepine antagonist used primarily to treat retrograde postoperative amnesia—as an antidote. The potentially paradoxical role of benzodiazepines in both the precipitation and treatment of TGA may relate back to the heterogeneity of the etiologies of TGA. Further research comparing the treatment of TGA in patients with stress-induced TGA vs postoperative TGA is needed to better understand the neurochemical basis of TGA and work toward establishing optimal treatment options for different patient demographics.
A generally favorable prognosis
TGA carries a low risk of recurrence. In studies with 3- to 7-year follow-up periods, the recurrence rates ranged from 1.4% to 23.8%.23,35,38
Memory impairments may be present for 5 to 6 months following a TGA episode. The severity of these impairments may range from clinically unnoticeable to the patient meeting the criteria for mild cognitive impairment.23,39 The risk is higher in patients who have had recurrent TGA compared to those patients who have experienced only a single episode.23
