Retention rates and successful treatment with antiseizure medications in newly-diagnosed epilepsy patients: Treatment of epilepsy with new generation ASMs

Purpose: Treatment for epilepsy primarily involves antiseizure medications
(ASMs), which can be characterized using the clinical data warehouse (CDW)
database. In this study, we compared retention rates and time to successful
treatment for various ASMs to reflect both efficacy and adverse effects in
patients with newly-diagnosed epilepsy.
Materials and Methods: We identified newly-diagnosed epilepsy patients with
ASM treatment for more than 12 months using CDW of a tertiary referral
hospital. Clinical characteristics were compared between groups with
successful and unsuccessful treatment. Cox regression analysis was
performed to evaluate independent variables of age, sex, comorbidities, and
attributes of ASM regimens.
Results: Of 2515 eligible participants, 46.2% were successfully treated with
the first ASM regimen, and 74.7% with all ASM regimens with median time-totreatment success of 14 months. Participants with second-generation ASM as
the first ASM were more likely to be successfully treated with the first regimen
compared to first-generation (51.6% vs. 42.3%, p<0.001) and more
successfully treated (HR=1.26, 95% CI: 1.15-1.39). Overall, valproic acid was
the most common ASM across wide range of ages under 65 years, while
levetiracetam in patients over 65 years or lamotrigine in female adult patients.
Clinical factors associated with less favorable treatment outcomes included
renal disease (HR=0.78; 0.66-0.92), liver disease (0.65; 0.52-0.81),
depression (0.70; 0.57-0.84), and mechanical ventilation (0.58; 0.50-0.67).
Discussion: Second-generation ASMs have the advantage of more successful
treatment with fewer ASM regimen changes compared with first-generation
drugs. Various comorbid conditions as well as age and sex should be
considered when selecting ASMs.