Abstracts

Rationale: Antiepileptic drug (AED) treatment and outcomes of patients with newly diagnosed epilepsy were analyzed to provide an understanding of the proportion and characteristics of patients who attain treatment stability. Potential predictors of treatment stability, including age, etiology, seizure type, and comorbidity were also examined.Methods: This retrospective cohort study was conducted using a US-based Truven Health MarketScan claims database covering over 100 million insured lives. Incident epilepsy cases were identified using ICD-9-CM codes (Table) and required a 2-year pre-index period (1 year for those aged 1 to <2 years; no enrollment period for those <1 year) and ≥1 year of follow up. The index date was the date of 1st treatment after epilepsy diagnosis. Treatment stability was defined as having no epilepsy-related hospital claims (ie, no emergency department or inpatient encounters with a principal diagnosis of epilepsy or seizure [ICD-9-CM codes of 345.xx or 780.3x]) and no changes in AED treatment (including discontinuing or adding or switching another AED) over a 365-day period. Outcomes included the proportion of patients attaining treatment stability.Results: Of a total of 36,035 new epilepsy cases, 17,106 patients had documented AED treatment with ≥1 year of follow up. Overall, 8,835 (51.6%) patients attained treatment stability, 48.4% with monotherapy and 3.2% with polytherapy; 54.7%, 55.9%, and 48.4% of those with focal, generalized, or undefined epilepsy, respectively, achieved treatment stability. Treatment stability with 1st-line therapy was reached by 41.6% of patients (N=7,111): 41.2% with monotherapy and 0.4% with polytherapy. Treatment stability with 2nd-line therapy was reached by 6.1% of patients (N=1,052): 4.2% with monotherapy and 1.9% with polytherapy. The percentage of patients attaining treatment stability decreased with successive lines of treatment across etiologies (Figure).Conclusions: About half of patients newly diagnosed with epilepsy achieved treatment stability after at least 1 year, with the majority reaching stability on 1st-line treatment. Monotherapy was associated with a higher proportion of patients reaching treatment stability than polytherapy. This observation was consistent across epilepsy etiologies and 1st- to 3rd-line treatments. UCB Pharma-sponsored.