Abstracts

RATIONALE: Catamenial epilepsy is a condition in which seizures are increased or occur exclusively during a certain phase of the menstrual cycle. Approximately 30% of women with epilepsy have catamenial tendencies. Acetazolamide (AZ) has been used for catamenial epilepsy based on reports of small groups of patients. The drug has a broad spectrum of action and a relatively favorable safety profile. However, efficacy in this group of patients has not been studied. The purpose of this study is to retrospectively analyze the efficacy and safety profile of AZ in women with poorly controlled catamenial seizures to determine the feasibility of a prospective trial. METHODS :Women with catamenial epilepsy admitted to the Epilepsy Monitoring Unit (EMU) at the CCF from 1990 through Dec 1999 were identified. Subjects were invited to participate in a retrospective telephone questionnaire addressing the relationship of seizures and the menstrual cycle and the use, efficacy, and adverse effects of AZ. Seizure outcome was classified as: seizure freedom, >75% reduction, 50-74% reduction and <50% reduction in seizure frequency. Seizure and menstrual calendars were reviewed when available. Responses to AZ were compared in women with different types of epilepsy using Fisher's exact tests for categorical data and 2-tailed t-tests for continuous variables. RESULTS: 71 women with catamenial epilepsy were identified and 30 (42%) had received or were currently taking AZ. 11% of patients were rendered seizure free, 7% had >75% reduction, 18% had 50-74% reduction and the remainder had <50% reduction in seizure frequency or were unchanged. Therefore 36% had at least a 50% or greater decrease in the frequency of seizures which is comparable to the efficacy of the newer antiepileptic drugs (AEDs). Response rates were similar in women with different epilepsy syndromes. Nearly 11% of treated women recalled a loss of efficacy over 6-24 months. No serious adverse effects were reported. CONCLUSIONS: Despite the small sample size and retrospective nature of this study, AZ appears to demonstrate some efficacy in the treatment of catamenial epilepsy. Based on these findings, plans for a prospective study are under consideration.