Vagal Nerve Stimulation in Developmental Encephalopathies and Epilepsy: A Narrative Review - Abstract
Purpose: Developmental epileptic encephalopathies (DEE) are a group of conditions featuring drug-resistant epilepsies and a large spectrum of comorbidities, which result in an enormous psychosocial burden. In the last decade, the use of vagus nerve stimulation (VNS) as adjuvant therapy for seizure control has been implemented. The purpose of this article is to collect evidence on the effectiveness of the use of VNS as adjuvant therapy in DEE Methods: PUBMED, EMBASE, and Cochrane databases were searched through April 2022 for original articles on VNS in DEE, without restriction on language or year of publication. Results: A total of 251 articles. All retrospective, including the following pathologies: CDKL5, Rett, tuberous sclerosis, progressive myoclonic epilepsies, non ketotic hyperglycinemia,Berardinelli-Seip syndrome, Gaucher III and Unverricht Lundborg were retrieved. These articles reported on a total of 116 patients, of which 12% presented an improvement of seizures between 80-100 %, 62% between 50-79%, 19% less than 50%. And only 7% showed no improvement.
Additionally, improvement of behavior, alertness, concentration, quality of life, and communication skills were reported. Conclusion: Of the total 116 patients, seizure reduction of more than 50% respect to the baseline was reported in 73% of them, associated with improvement of alertness, behavior, and neurodevelopment. Although VNS had mainly palliative effects our findings may suggest a favorable impact of this non-pharmacological therapy in this very difficult-to-treat group of epilepsies. Prospective studies are required to evaluate not only the reduction in seizure frequency but also these other qualities of life parameters.