Long-Term Risk of Stroke, Seizures and Cognitive Impairment After Transient Global Amnesia: A Case-Control, Population-Based Study with Long Term Follow Up (P1.114)

Objective: To study long term risk of stroke, seizures and cognitive impairment after Transient Global Amnesia (TGA). Background: TGA is generally considered to be a benign condition. However, there are limited data available regarding the long-term incidence of stroke, seizures and cognitive impairment after an episode of TGA. Methods: All patients diagnosed with TGA in Olmsted County, Minnesota between 1985 and 2010 were ascertained from the Rochester Epidemiology Project database. TGA was defined clinically. Medical records were reviewed to assess premorbid conditions and events during follow up. Age- and sex-matched controls without TGA at baseline and with similar length of follow up were randomly selected from the same population. Categorical variables were compared using Fisher’s exact test and continuous variables using Wilcoxon rank sum test. Events of interest were studied using Kaplan Meier survival plots and log rank test. Results: 221 cases of TGA and 221 age- and sex-matched controls were included in the analysis. Mean duration of follow up was 12 years in both groups. Baseline prevalence of vascular risk factors was similar between both groups. There was no difference in history of seizures. Prior migraine was significantly more common in the TGA group (14.0[percnt] vs 5.4[percnt]; p<0.0001). No significant differences between cases and controls were found in the incidence of stroke, seizure and cognitive impairment during follow up. There was also no difference in modified Rankin scale at last follow up, nor was there any difference in mortality. When stroke, seizure or cognitive impairment occurred during follow up, there was no significant difference between cases and controls on their time of occurrence. Conclusions: The long-term risk of stroke, seizure and cognitive impairment is not increased after TGA. Migraine appears to be a risk factor for presenting TGA. Disclosure: Dr. Arena has nothing to disclose. Dr. Mandrekar has nothing to disclose. Dr. Singh has nothing to disclose. Dr. Brown has nothing to disclose. Dr. Rabinstein has received royalty payments from Elsevier and Oxford University Press. Dr. Rabinstein has received research support from DJO Global.