Abstracts

The Neurophysiology and Cognitive Profile of Late-onset Unexplained Epilepsy

Abstract number : 1.351
Submission category : 11. Behavior/Neuropsychology/Language / 11A. Adult
Year : 2022
Submission ID : 2203959
Source : www.aesnet.org
Presentation date : 12/3/2022 12:00:00 PM
Published date : Nov 22, 2022, 05:22 AM

Authors :
rani sarkis, MD, MSc. – Brigham and Women's Hospital, Harvard Medical School; Janet Orozco, BS – Brigham and Women's Hospital; Steven Stufflebeam, MD, PhD – Massachusetts General Hospital; Anand Viswanathan, MD – Massachusetts General Hospital; Rebecca Amariglio, PhD – Massachusetts General Hospital; Malika Purandare, BS – Brigham and Women's Hospital; Patrick Trouten, BS – Brigham and Women's Hospital; page Pennell, MD – University of Pittsburgh Medical Center; Gad Marshall, MD – Brigham and Women's Hospital

Rationale: Late-onset unexplained epilepsy (LOUE) has been associated with a higher risk of dementia. The reasons for this elevated risk are unclear, and there is a need to understand its pathophysiology and whether neurodegenerative and cerebrovascular pathologies contribute to its etiology. The goal of the study was to characterize the cognitive profile, EEG, and MRI findings of patients with LOUE.

Methods: A total of 37 participants were prospectively recruited from Brigham and Women’s Hospital and affiliated hospitals. Inclusion criteria: new-onset seizures within 3 years, age ≥60 years, absence of cortical lesions on MRI and provoking factors. Subjects underwent the Clinical Dementia Rating (CDR) Scale and a neuropsychological battery to assess 4 cognitive domains: Preclinical Alzheimer Cognitive Composite (PACC), delayed verbal recall (Free and Cued Selective Reminding Test and Logical Memory), processing speed (Trailmaking Test A, Digit Symbol Substitution Test), and executive function (Trailmaking Test B and Controlled Oral Word Association Test).
_x000D_ A 24-hour EEG was obtained within 1 year of cognitive assessment and evaluated for the presence of abnormalities. Additionally, MRI volumetric analysis of hippocampal (HV), amygdala (AV), and white matter hyperintensity volumes (WMV) was performed, and a hippocampal asymmetry index was calculated. The control group consisted of participants from the Harvard Aging Brain Study (73.3 ± 5.5 years, 59% female) who underwent the same MRI protocol and cognitive battery.

Results: Mean (±SD) age was 69.4 ± 6.1 years and 46% were female. Global CDR (n=35) scores were 0.0 (n=22), 0.5 (n=12), and 1 (n=1). Ambulatory EEG findings included focal slowing (n=22), bi-temporal (n=6), left-temporal (n=8), right-temporal (n=4), and right frontal+parietal (1) epileptiform abnormalities. Twenty-six subjects were on antiseizure medication (ASM) monotherapy, 10 on polytherapy. The mean z-score, compared to controls, for PACC was −0.58 (range, -3.75, 1.01), delayed verbal recall −0.81 (−3.72, 1.20), processing speed −0.49 (−5.89, 1.60), and executive function −0.32 (range, −3.51, 1.63). When controlling for age, gender, and education, the LOUE group exhibited worse performance on PACC (p< 0.0001) and delayed verbal recall (p< 0.0001).
Behavior