Different risk factor profiles between transient global amnesia and transient ischemic attack: a large case-control study.

BACKGROUND: The pathophysiology of transient global amnesia (TGA) is not fully understood. This study was conducted to identify the cardiovascular risk factors of TGA compared to those of transient ischemic attack (TIA) and normal controls, using a large number of subjects. In addition to the comparison of risk factors, an association between the observed cardiovascular risk factors in the current study and a pathophysiological mechanism recently investigated was speculated upon.
MATERIALS AND METHODS: We performed a retrospective case-control study that compared 293 TGA patients to 632 TIA patients and 293 age- and sex-matched normal controls. Demographic details and cardiovascular risk factors were carefully recorded.
RESULTS: TGA patients had a significantly higher prevalence of ischemic heart disease and hyperlipidemia; however, they had a lower prevalence of hypertension, diabetes mellitus, ischemic stroke and atrial fibrillation when compared to TIA patients. When compared to age- and sex-matched normal controls, TGA patients also had a significantly higher prevalence of hyperlipidemia, previous ischemic stroke and ischemic heart disease.
CONCLUSION: The cardiovascular risk factors identified in TGA patients in this study were different from those of previously reported studies. This disproportionate prevalence of cardiovascular risk factors may constitute possible evidence that TGA and TIA differ in their pathophysiological mechanism. In addition, some cardiovascular risk factors, such as hyperlipidemia and ischemic heart disease, should be regarded as possible risk factors of TGA.