Evaluation of cognitive and language side effects of topiramate in patients with epilepsy, and effectiveness of counseling and speech therapy interventions

Topiramate (TPM) is a highly effective antiepileptic drug. Up to 10% of patients experience TPM-related cognitive side effects, especially on language (impaired word finding and verbal fluency), with a drug discontinuation rate up to 70%. We investigated early cognitive and language deficits in patients on TPM for epilepsy and the possible favorable effect of counseling and speech therapy interventions. Out of 380 outpatients screened, 29 were on TPM and 10 met the study inclusion criteria. All patients showed good participation and increasing engagement in the study, excepting for 1 who discontinued it for personal reasons. At baseline all participants showed normal verbal and total IQ scores. 5 patients (56%) showed frankly pathological verbal fluency, either phonemic or semantic, and improved up to normal values at the end of treatment (p<0.05). This improvement persisted after the 4-month maintenance period. Our results suggest the effectiveness and feasibility of a counseling and speech therapy treatment in patients with TPM-related language involvement, warranting future studies on wider sample and follow-up.