NEW ORLEANS—The prevalence of epilepsy does not differ among patients with different types of dementia, researchers reported at the 2013 Annual Meeting of the American Neurological Association. However, cognitive decline in patients with dementia-related epilepsy occurs more rapidly than in patients who are seizure-free, and patients with vascular dementia develop epilepsy earlier than do patients with Alzheimer’s disease.
Tyler Webb, MD, and colleagues sought to determine whether epilepsy was more common in vascular dementia, Alzheimer’s disease, or other types of dementia. The researchers also wanted to determine whether dementia-related epilepsy leads to faster cognitive decline and whether epilepsy develops earlier in those with vascular dementia.
“Seizures have a well-known and well-documented association with Alzheimer’s disease when compared to age-matched controls,” stated Dr. Webb, a senior resident in the Department of Neurology, University of Oklahoma College of Medicine in Oklahoma City. “However, the association, or lack thereof, between seizures and other neurodegenerative disease has not been as clearly elucidated.”
Dr. Webb and colleagues based their findings on a retrospective chart review of 195 patients with dementia (ages 50 to 90), including those who were also diagnosed with epilepsy within five years of dementia onset. The investigators used two Mini-Mental Status Examination (MMSE) scores that were separated by more than nine months to estimate the progression of dementia, and the study authors adjusted the estimate for time from dementia diagnosis.
“The prevalence of epilepsy in vascular dementia did not differ significantly from Alzheimer’s disease,” reported Dr. Webb. “Patients with dementia-related epilepsy exhibited a significantly more rapid decline of MMSE scores—1.75 points per year—than the seizure-free group.
“The decline of MMSE scores after a minimum of nine-month follow-up among those with and without epilepsy revealed a significantly more rapid decline in the epilepsy group,” Dr. Webb continued. “Time-to-event curves show a shorter time course of dementing illness before the development of seizures among those patients with vascular dementia compared with those who had Alzheimer’s disease.”
—Colby Stong