Prevalence and nature of patient-reported antiseizure medication side effects in a Swedish regional multi-center study

Abstract

PurposeSide effects is one of the major clinical problems in epilepsy care. We assessed the prevalence of ASM side effects in participants in a large regional multicenter observational study in western Sweden and aimed to identify risk factors and inventory the nature of side effects with different ASM regimes. MethodsCross-sectional analysis of survey answers and clinical characteristics of 406 adult participants recruited to a regional observational study between December 2020 and March 2023. Half of the participants had been seizure free for one year. Second-generation or newer ASMs were the most common. ResultsA total of 164 (40 %, 95 %CI: 36–45) patients reported side effects. Patients reporting side effects were younger (median 41 vs 47 years, p = 0.015), had more frequently experienced a seizure in the last year (p = 0.02), and were more often on ASM polytherapy (p < 0.01). ASM polytherapy and age were significant risk factors in regression models, but the explanatory value was low. The most common side effect was tiredness followed by cognitive symptoms. ConclusionsOur findings show that side effects are still common in epilepsy care and suggests that unnecessary polypharmacy should be avoided. Apart from number or ASMs, predicting who will experience side effects is difficult and more research on individual vulnerability is needed.