Catamenial Epilepsy and Menopause

Abstract

To the Editor: We read with interest the analysis of the impact of menopause on epilepsy recently reported by Harden et al. 1. I would like to comment on their findings in patients who reported having had a catamenial seizure pattern before menopause. The study was done retrospectively, and patients were asked to report the course of their epilepsy over time. The definition of catamenial epilepsy was adapted from Herzog et al. 2. As a result, a history of catamenial seizure pattern was significantly associated with a decrease in seizures at menopause. The authors concluded that a catamenial seizure pattern may be an endogenous factor influencing the course of epilepsy. However, the method applied is not appropriate to draw such a conclusion: women with epilepsy often believe that their seizures are related to their menstrual cycle. Not surprisingly, the number of patients with catamenial seizures varies in different studies and may be as low as 12.5%3 and as high as 72%4. In my own prospective study of 21 women who reported having increased seizures related to their menstrual cycle, catamenial seizures could be documented in only 24%5. Therefore, a retrospective study not based on the analysis of seizure diaries will overestimate the number of patients with catamenial seizures. Therefore, I advise not drawing final conclusions from the reported data with respect to the correlation between catamenial seizures and menopause 1.