Abstracts

Rationale: Refractory epilepsy is a diagnosis of recurrent seizures which requires multiple resources for optimal chronic management. The disease negatively impacts the lives of affected patients and families, and it poses an economic burden to the healthcare system. There are multiple treatment options for patients with refractory epilepsy, including but not limited to the continuation or addition of antiepileptic drugs (AEDs), and vagus nerve stimulation (VNS) involving the implantation of a medical device. This study compared hospital-based costs between pediatric patients treated with AEDs only and AEDs plus VNS.

Methods: Patients aged 0-17 years who were diagnosed with refractory epilepsy between 1st January 2011 and 31st December 2016 were identified from the Children's Hospital Association's Pediatric Health Information System (PHIS) database. Patients treated with AEDs only or AEDs plus VNS were included in the study. Children were followed one year prior and two years after meeting pre-determined criteria for refractory epilepsy. All-cause and epilepsy-related hospital costs were calculated as mean annual costs during the pre-index and post-index periods and included total costs, inpatient costs, outpatient costs, and ED costs. Costs of the implanted device were included in those of the surgical encounter on the index date. The difference-in-difference (DID) approach along with two-part models was used to compare the changes in mean hospital-based costs captured in the PHIS database over time between patients treated with AEDs only and AEDs plus VNS.

Results: The cohort included 3471 patients treated with AEDs only and 1113 patients treated with AEDs plus VNS. The total hospital costs increased in both groups over time, with the AEDs only group incurring the highest costs. At the follow-up time of 2 years after the index date, for the AEDs only cohort, the adjusted all-cause and epilepsy-related mean annual total costs increased by $14,715 (95% CI: $12,375 to $17,055) and $18,437 (95% CI: $15,978 to $20,896), respectively. By comparison, the adjusted all-cause and epilepsy-related mean annual total costs of the VNS cohort increased by $12,838 (95% CI: $8,171 to $17,505) and $15,183 (95% CI: $10,253 to $20,113), respectively. The total difference in hospital-based costs was on average $3,254 for epilepsy-related mean annual costs per year for each of the first 2 years after the index date, with the cost savings in favor of the AEDs plus VNS group over the AEDs only group. Cost savings were higher in the second year after intervention than the first year following the index date.

Conclusions: Compared to AEDs alone, AEDs plus VNS is a treatment modality associated with lower annual hospital-based costs over time. Our study shows VNS is a cost-beneficial treatment for a national U.S. cohort of pediatric patients with refractory epilepsy.

Funding: Please list any funding that was received in support of this abstract.: Sandi Lam is funded by PCORI RD-2020C2-20356 and reports an investigator-initiated study award from LivaNova.