Abstracts

Rationale: Limited data are available on the current treatment patterns in women of child bearing age with epilepsy. Teratogenicity risk is associated with polytherapy and the use of certain drugs. These data are important in understanding the current population risk among women of child bearing age. Methods: This retrospective observational study used the US-based Truven Health MarketScan Commercial and Medicare and Medicaid insurance claims database to analyze data from women of child bearing age (15-44 years) with incident or prevalent epilepsy. Cases required an ICD–9-CM-coded epilepsy diagnosis with continuous medical/pharmacy enrollment during the baseline period (Table 1). Incident cases had an index date between Jan 2010-Jun 2013 and a prior baseline of 2 years without an epilepsy diagnosis or AED prescription. Prevalent cases had an index date between Jan 2009-Jun 2013 and a prior 1-year baseline. AED treatment patterns during the follow-up period were described. Treatment was classified as monotherapy (1 AED for ≥90 continuous days) or polytherapy (≥2 AEDs for ≥90 days). Results: 8,003 incident and 38,764 prevalent cases of women aged 15-44 years were identified. The overall number of AED treatment lines for incident cases were 0 (44.3%), 1 (23.8%), 2 (20.1%), 3 (6.6%), and ≥4 (5.2%), respectively. Of the 4,459 incident patients receiving AED treatment, 71.2% received monotherapy and 1.0% received polytherapy for ≥90 days as first-line treatment; 27.8% of treated patients received treatment for < 90 days as first-line treatment. For the 38,764 prevalent patients receiving AED treatment, 49.0% were treated with monotherapy, 23.9% with polytherapy, 2.7% had treatment for < 90 days, and 24.5% did not have any AED treatment. The most commonly prescribed AEDs as monotherapy for incident cases were levetiracetam (28.2%), topiramate (11.0%), lamotrigine (10.9%), gabapentin (4.2%), and valproate (3.4%). For prevalent cases, the most frequently prescribed AEDs as monotherapy were lamotrigine (10.1%), levetiracetam (9.5%), topiramate (6.1%), carbamazepine (5.2%), and valproate (5.0%). There were differences in monotherapy by seizure type comparing focal with generalized both for incident (valproate 2.0% vs 4.3%; phenytoin 1.8% vs 4.1%; oxcarbazepine 6.0% vs 1.7%) and prevalent cases (valproate 2.8% vs 6.8%; carbamazepine 7.1% vs 4.3%; phenytoin 1.6% vs 2.3%; oxcarbazepine 5.1% vs 1.7%). Among all treated patients, monotherapy with newer generation AEDs predominated in incident cases (81.2%) as well as prevalent cases (71.9%). Patients with generalized epilepsy were slightly more likely to be treated with older generation AEDs as monotherapy than those with focal epilepsy both among incident cases (14.7% vs 9.3%) and prevalent cases (14.8% vs. 11.9%). Conclusions: Most women of child bearing age with epilepsy are treated with newer generation AEDs. However, a noticeable proportion of women are still treated with AEDs with known teratogenicity risks, such as valproate, phenobarbital, and topiramate. Valproate is prescribed even for incident cases with focal epilepsy. Funding: UCB Pharma-sponsored.