Abstracts

It is still controversial how to reduce or discontinue antiepileptic drugs (AEDs) without a risk of relapses in patients who have no seizure for years. We present the long-term prognosis of epilepsy patients who have had relapses while dose reduction of AEDs and evaluate their subsequent long-term outcome., 18 patients (10 males, 8 females) who had relapse while they had AED dose reduction were collected. We followed them for 12 [sim] 27 years (mean; 18 years) after relapses. Their age ranged between 26 and 59-year-old (mean; 47-year-old), seizure onsets ranged between 10 months and 20 years. Idiopathic generalized epilepsy was diagnosed in 5 patients, symptomatic generalized epilepsy in 1 patient, and localization-related epilepsy in 12 patients. No patient had surgical treatment. Their seizure free period ranged between 21 months and 9 years prior to dose reduction (mean; 5.1 years). We compared the number and dose of AEDs before dose reduction and at present, also examined the clinical course during the follow-up period., The duration between change in AEDs dose and the relapse was [lt]/= 2 month in 7 patients, 3 [sim] 12 months in 4 patients, 13 [sim] 24 months in 5 patients, and 48 months [lt] in 2 patients. The last two patients relapsed after they delivered, and they had fatigues, sleep deprivations, and change in life styles.
On follow up, patients were taking 1[sim]3 types of AEDs (mean 1.33) compare to 1[sim]4 types of AEDs (mean 2.16) prior to dose reduction. 13 (72.2%) of 18 patients were still reduced AEDs compared to what they had taken prior to dose reduction. Three patients had same AEDs. Two patients were taking greater doses of AEDs.
In all patients, AEDs were increased after relapses. After that, 10 (56%) of 18 patients had no subsequent seizures. 5 (28%) of 18 patients had1[sim]3 seizures after relapses, but were seizure free for more than 9 years since then. Of the last three patients, two patients had yearly partial seizures. They reduced their medication from 2[sim]3 kinds of AEDs to one AED, and we did not further change AED because of their requests. The remaining one patient had two seizures in 16 years due to non-compliance., The results suggest the AEDs necessary to prevent relapses can alter during long-term follow up in some patients. Lower dose of AEDs become adequate to control seizures compared to the earlier regimen. Thus, AEDs dose reduction should be considered for patients who have no seizure for years. However, the final decision should be decided based on the their clinical and social-cultural profile.
Our data also suggest that reduction of AEDs has a potential of relapses for the patients with no seizure for long period, however the seizure outcomes and dosage of AEDs were still favorable for long term follow-up, dose reduction did not make their prognosis worse.
Further investigations in a larger population and using EEG could be valuable for clinical practice.,