The assessment of the impact of antiepileptic drugs on cognitive functions via N-200/P-300 potentials and neuropsychological measures.

Objective: The effects of antiseizure medications (ASMs) on cognitive functions have not been fully elucidated. The primary aim of this study was to demonstrate potential changes in cognitive functions in patients diagnosed with epilepsy from both neuropsychological and electrophysiological perspectives. Our secondary objective was to assess the effects of administered ASM on cognitive functions by categorizing patients into different monotherapy and polytherapy groups.

Materials and methods: A single-center, prospective patient registry study was conducted between May 2022 and June 2023. The inclusion criteria included epilepsy patients aged 18 to 50 years who were receiving ASM) treatment, either as inpatients or outpatients, and who did not have any syndromic diagnosis that may lead to cognitive disfunciton (such as primary progressive myoclonic epilepsies, Down syndrome and so on), and did not diagnosed previously or during examination that could affect dementia or cognitive functions. Patients who were scheduled to initiate new ASM treatment were evaluated using the Montreal Cognitive Assessment (MoCA) scale and Event-Related Potentials (ERP) assessment both before commencing treatment and three months thereafter.

Results: A total of 320 participants were included in the study; 20 healthy controls and 300 epilepsy patients were included. Statistically significant differences were observed between the healthy control group and the epilepsy group in terms of average Montreal Cognitive Assessment (MoCA) scores and event-related potentials (ERPs) (n200, p300 latencies, n2p3 amplitudes) (p<0.05). Similarly, statistically significant differences were observed between the monotherapy and polytherapy groups in terms of average MoCA and ERP scores (p<0.05).

Conclusion: This study demonstrated the detrimental effects of certain ASMs, particularly topiramate and carbamazepine, on cognitive functions. Furthermore, the negative impact on cognitive performance became more pronounced with an increasing number of concurrently used ASMs (polytherapy), with topiramate showing notable effects.