Evaluation of persistence and healthcare utilization in patients treated with anti-seizure medications as add-on therapy: A nationwide cohort study in South Korea.

OBJECTIVE

To compare medication adherence and healthcare utilization among patients who were treated with anti-seizure medications (ASMs) as first add-on to monotherapy for epilepsy using the national health insurance claims data.

METHODS

A retrospective observational cohort study was conducted using the Korean National Health Insurance claims data. Patients who received ASM as first add-on to monotherapy during January 2017 to February 2018 were included. The selected patients were followed up for 12 months to evaluate persistence, adherence, and healthcare resource utilization.

RESULTS

In total, 4277 patients who received ASM as first add-on to monotherapy for epilepsy were enrolled. The mean treatment duration of add-on ASM was 296.6 ± 108.6 days during the 1-year follow-up period and 64.3% of the total population were persistent on the add-on ASM at 365 days from the index date. The mean medication possession ratio (MPR) was 90.3 ± 23.7 and the proportion of adherent patients with ≥80% MPR was 79.3%. Lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), and perampanel (PER) groups showed significantly higher persistence and adherence than carbamazepine (CBZ), topiramate (TPM), and valproate (VAL) groups during the 1-year follow-up period. Significant differences in length of stays, total hospitalization cost, outpatient visit cost, and emergency cost were shown between ASM groups and LTG, LEV, OXC, and PER showed relatively low utilization and cost.

CONCLUSIONS

Better adherence was observed in LTG, LEV, OXC, and PER groups than in CBZ, TPM, and VAL groups. Healthcare utilization and related costs showed significant difference between ASM groups.