Comparative study of Pre and Post-operative Drug Costs in Patients with Refractory Epilepsy Undergoing Hemispherectomy and Temporal Lobectomy at the National Children’s Hospital Dr. Carlos Sáenz Herrera

Introduction: Refractory epilepsy can be defined as a failure of adequate trials of antiepileptic drug programs tolerated and appropriately chosen and used (either as monotherapy or in combination) to achieve sustained freedom from seizures. Surgical procedures for the control of epileptic seizures have spread throughout the world, however, large medical centers have mainly focused on studying and analyzing the clinical results of their surgical interventions. For this reason, this study aims to analyze the cost of pre and post-surgical anticonvulsant medications in patients. Objective: To analyze the relationship between preoperative cost / postoperative cost of antiepileptic drugs in patients undergoing hemispherectomy or temporary lobectomy at the National Children’s Hospital (Hospital Nacional de Niños-HNN). Materials and methods: This study is a retrospective, descriptive, quantitative and longitudinal type of a series of patients who were operated in the Epilepsy Monitoring and Surgery Unit (UMCE) of Costa Rica, between November 2000 and December 2018. Information on the history of medications is obtained from patients before and after having undergone hemispherectomy or temporal lobectomy to assess whether or not there is an economic saving in this aspect when comparing both periods of time. Results: 69 patients have undergone hemispherectomy and temporal lobectomy since the creation of the UMCE in November 2000. Of these, 18 (26%) underwent hemispherectomy and 51 (74%) underwent temporary lobectomy. A sample of 31 patients (45%) were obtained, which met the inclusion criteria. The average age of initiation of treatment at the HNN was 5.5 years old (66 months) and the average age at which they underwent surgery was 10.8 years old (130 months). There was one patient in the sample who received 9 anticonvulsant medications before undergoing the surgical procedure and the average number of medications used pre-surgically was 4.45 anticovulsivants per patient. The average postoperative medication was 2.35 anticonvulsivants per patient. The average monthly preoperative cost was $50.17, while the postoperative period was $31.26, with a difference of $18.91. A total of 9 patients in the sample increased the monthly postoperative cost. The total savings per month in the patients included in the sample was $586.36 and extrapolated to the population of 69 patients resulting in a saving of $1,305.14 per month. The projection according to the life expectancy of the patients in the sample translates into a saving of $409,188.59 while the projection to the 69 patients would result in a saving of $910,774.60 for the Caja Costarricense del Seguro Social (CCSS - Costa Rican Social Security Fund). Discussion: The effectiveness of these two surgeries in suitably selected patients is reflected in the economic savings represented by antiepileptic drugs administered after these surgical procedures. Conclusion: we consider that in this center the patients who have been operated have meant a saving for the Caja Costarricense del Seguro Social (CCSS) since they have diminished or completely eliminated the anti-epileptic medical treatment