Abstracts

Pharmacological treatment in the elderly is made difficult due to the potential for drug interactions. This patient population is also at risk for adverse events such as impairment of cognition and gait stability. Levetiracetam (LEV) may offer significant improvement as it lacks hepatic metabolism and was generally well tolerated in clinical trials.
We prospectively identified all patients initiated on LEV in our clinic who are older than 60 years of age. For seizures: age of onset, type and frequency were logged. Results of EEG, MRI, prior drug trials and the reason given for initiating LEV treatment were also noted. On LEV, concomitant anti-epileptic drugs (AEDs), adverse events, LEV discontinuation, LEV serum concentrations and serum creatinine were charted.
Eighteen patients between the ages of 60 and 87 (median age 76) have been treated with LEV in our out-patient clinic
Four patients had newly identified epilepsy with LEV as the first treatment. They have been receiving total daily doses of 500 to 1000 mg for 8 to 11 months. The only adverse event was a seizure in one patient at the lower dose but none thus far on 1000mg/day. Two were diagnosed within 6 months of first seizure and received a prior AED. One could not tolerate extended release carbamazepine in terms of cognition or gait. She has received 1000 mg/day of LEV in monotherapy without further seizures or significant side effects. The other with recent onset of seizures and a history of chronic anxiety has not been able to tolerate LEV, or any other drug.
The remaining 12 patients had median seizure duration of 29 years (range 5 to 68 years). Six of these chronic patients received LEV for intractable seizures. Two have been seizure-free (one on monotherapy) for 12 to 16 months at doses of 500 to 1000 mg/day. Three have had 0 to 25% reduction in seizures on polypharmacy with LEV doses of 500 to 4000 mg/day. The remaining patient showed a dose-dependent increase in seizure frequency on LEV. There was a five-fold increase in seizures at 2500 mg/day. Six chronic patients were converted to LEV monotherapy to attempt to improve cognition and gait. Five have been seizure-free for five to 17 months on doses of 500 to 1000 mg/day. One had a seizure after six months on 500 mg/day and his dose has been increased. These patients reported clear improvement in functional status.
LEV serum concentration has been measured in six elderly patients receiving 500 - 1000 mg/day. Individual serum concentrations in ascending order were 9,11,19, 27, 28, and 28.
Our experience with a small population of elderly epilepsy patients suggests that LEV is efficacious and well tolerated in new onset cases and in chronic patients who are no longer tolerating first generation anti-epileptic drugs. Doses of 500 to 1000 mg/day in divided dose were highly effective in the elderly and produced serum concentrations within the range reported in the pivotal clinical trials at much higher doses. Further study of LEV efficacy and tolerability in the elderly should be pursued.