Outcome of newly-diagnosed epilepsy in older patients

Abstract

Introduction: The annual incidence of seizure disorders rises sharply after the age of 60. Treatment is complicated by the normal physiological changes of aging, comorbid diseases, and polypharmacy. Despite this, approximately 80% of the patients become seizure-free.

Objectives: The objectives of this study were to (1) analyze the outcome of a cohort of patients with newly-diagnosed epilepsy over the age of 65, (2) describe epilepsy etiology and seizure type, and (3) classify the outcome according to the latest ILAE classification proposal for drug-resistant epilepsy (2010).

Methods: All patients with newly-diagnosed epilepsy over the age of 65 who were evaluated in two different institutions were included. Seizures and epilepsy syndromes were classified according to the International League Against Epilepsy proposal (2010). Epilepsy outcomes were also analyzed according to the proposal of the ILAE Commission on Therapeutic Strategies (2010).

Results: One hundred and twenty-two patients were included with a median follow-up time of 15 months. Median age of diagnosis was 78 years. Seventy-seven patients (55%) had epilepsy of unknown cause, and 55 (45%) had structural-metabolic epilepsy. The proportions of seizure-free patients at 6, 12, 18, and 24 months were 90%, 77%, 74%, and 67%, respectively. Thirty percent of patients experienced adverse effects (AEs). We found a statistically significant trend toward a higher frequency of AEs as the number of concomitant medications rose and in younger patients. According to the 2010 ILAE classification proposal for drug-resistant epilepsy criteria, 55.8% of the patients were seizure-free, 12.3% had treatment failure, and 32% had undetermined seizure outcome.

Conclusion: Patients with newly-diagnosed epilepsy after the age of 65 have very good chances of achieving seizure control with AED treatment. It seems that fulfilling the ILAE classification proposal for drug-resistant epilepsy (2010) criteria for seizure freedom was more difficult in our cohort. Older patients also seem to be more prone to suffering from AEs.