Which factors correlate with memory difficulties in epilepsy?

Certain older adults with epilepsy have worse 24-hour memory retention, particularly those with greater frequency of interictal epileptiform activity (IEA), reduced slow wave activity (SWA) power during nonrapid eye movement (non-REM) sleep, and higher burden of antiseizure medications, according to a study.

The study included 55 adults with epilepsy who were over 50 years of age. They completed a declarative memory task involving the recall of the positions of 15 card pairs on a computer screen before a 24-hour ambulatory electroencephalogram (EEG).

Researchers evaluated the percentage of encoded card pairs that were correctly recalled after 24 hours (24-hour retention rate) and calculated global SWA power during non-REM sleep. EEG results were also examined for the presence and frequency of scalp IEA and scored for total sleep.

A total of 44 participants completed the memory task successfully. Of these, two were subsequently excluded due to seizures recorded on EEG. The final cohort comprised 42 participants (mean age 64.3 years, 52 percent women), and their average 24-hour memory retention rate was 70.9 percent.

On multivariate regression analysis, several factors significantly predicted 24-hour memory retention. These factors included number of antiseizure medications (p=0.013), IEA frequency (p=0.0094), and SWA power (p=0.02).

The present data may have important implications, with the factors representing potential treatment targets to improve memory in older adults with epilepsy.