Outcome of initial antiepileptic drug treatment in elderly patients with newly diagnosed epilepsy.

Purpose: A study was carried out to assess the outcome of initial antiepileptic drug (AED) monotherapy in elderly patients with newly diagnosed epilepsy and to investigate the cumulative probabilities of ≥2- and ≥5-year complete seizure remission and the factors that may have an effect on the outcome of AED treatment and the response to successive AED regimens.

Methods: From the medical records of Kuopio University Hospital, Finland, the researchers identified a community-dwelling cohort of elderly subjects (aged 65 or above at the time of diagnosis; n=529) with newly diagnosed epilepsy. The seizure outcome and the effect of initial prescription of AEDs were retrospectively studied.

Results: All told, 336 (64%) of the patients used the initial AED for the whole follow-up period, while the treatment was changed for 193 (36%) of the patients. In total, 456 (86%) of the 529 patients were treated with monotherapy until the end of follow-up. Four per cent of the patients developed refractory epilepsy. The response to the second monotherapy after failure of the first monotherapy was similar between patients whose treatment failed for reason of intolerable side effects and those showing failure due to inadequate seizure control. The estimated cumulative probability of achieving ≥2 years' remission was 83%, and that for achieving ≥5 years of remission was 79%. Early response to treatment was a statistically significant predictor of remission.

Conclusion: The prognosis of seizures in elderly patients with newly diagnosed epilepsy is good, and most patients can be successfully treated with the first AED. Patients who do not become seizure-free within the first year may be at risk of displaying a drug-resistant seizure disorder.