Abstracts

Rationale: To evaluate the prevalence of catamenial patterns (CP), defined as ≥2-fold average daily seizure frequency (ADSF) in specific menstrual phases, in a heterogenous cohort of women with epilepsy (WWE) on no hormonal therapies. Methods: The 89 WWE enrolled in the prospective, observational study, Women with Epilepsy: Pregnancy Outcomes and Deliveries (WEPOD), were evaluated for entry criterion into this secondary analysis: >1 menstrual cycle prospectively tracked in the electronic diary app and >1 seizure during tracking. Women with focal and generalized-onset seizures were included. Progesterone levels for 1-3 cycles/participant determined if a cycle was an/ovulatory. CP were defined as >2-fold ADSF during menstrual days -3 to +3 compared to follicular/luteal phases (C1); days +10 to -13 compared to follicular/luteal phases (C2), and for anovulatory cycles, days +10 through +3 compared to follicular phase (C3). An arbitrary “B” pattern was used to compare rates of participants falling into a random pattern compared to the CPs. B was defined as >2-fold ADSF during follicular phase (days +4 through +9) compared to all other days.At the time of screening, each WWE was asked about her historical seizure patterns and if she had noted a relationship to her menstrual cycles. Results: Twenty-three WWE were included in this secondary analysis. Twelve of 23 (52.3%) met criteria for at least one CP. Seven of 23 (30.4%) WWE fit a C1 pattern; 3/23 (13%) a C2 pattern,; and 3/5 women with anovulatory cycles fit a C3 pattern. One participant fit both C1 and a C2 CP. One of 23 (4.3%) fit the random B pattern. The women with CP had varied seizure types, epilepsy syndromes, and were taking different anti-seizure medicines. There were no differences in ADSF, days tracked preconception, months with progesterone measurements, or proportion of months anovulatory between the WWE fitting CP and those not fitting CP definitions. Twelve participants reported seizure worsening related to their menstrual cycles historically. Only 6/12 demonstrated a prospective CP; 6/11 of the participants who reported no prior catamenial pattern demonstrated a prospective CP. (Fisher’s Exact Test, p=0.7998). Conclusions: The prevalence of the C1 CP in this heterogenous cohort of WWE tracked prospectively is similar to reports in women with drug resistant temporal lobe epilepsy. Our data suggests no differences in likelihood of having a CP between those who reported a prior CP and those who did not. Larger prospective studies are needed in to confirm these findings and to inform potential therapeutic trial designs for catamenial epilepsy. Funding: Epilepsy Foundation