Neuromodulation in refractory epilepsy: Brazilian specialists consensus

Effects of vagus nerve stimulation on cognitive function in patients with epilepsy: a systematic review and meta-analysis

Background

Previous studies showed that vagus nerve stimulation (VNS) can improve cognitive function in patients with epilepsy, but there is still great controversy about the effect of VNS on cognitive function in patients with epilepsy.

Objective

To investigate the effect of VNS on the cognitive function of epilepsy patients.

Methods

Clinical trials published in PubMed, The Cochrane Library, and Embase before September 20, 2022, were comprehensively searched. Primary outcomes were overall cognitive performance, executive function, attention, memory; Secondary outcomes were seizure frequency, mood, and quality of life (QOL). Random effects were used to calculate the pooled outcome.

Results

Twenty clinical trials were included. There was no significant improvement in overall cognitive performance in patients with epilepsy after VNS treatment (SMD = 0.07; 95% CI: -0.12 to 0.26; I2 = 0.00%) compared to pre-treatment. Compared to pre-treatment, there was no significant difference in executive function (SMD = -0.50; 95% CI: -1.50 to 0.50; p = 0.32), attention (SMD = -0.17; 95% CI: -0.43 to 0.09; p = 0.21) and memory (SMD = 0.64; 95% CI: -0.11 to 1.39; p = 0.09), but there were significant differences in seizure frequency, mood, and quality of life in patients with epilepsy after VNS.

Conclusion

This meta-analysis did not establish that VNS can significantly improve cognitive function in patients with epilepsy, but it shows that VNS can significantly improve the seizure frequency, mood and quality of life of patients with epilepsy.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42023384059.

Saudi Arabian Consensus Statement on Vagus Nerve Stimulation for Refractory Epilepsy

Vagus nerve stimulation (VNS) is an approved adjunctive therapy for refractory epilepsy and used in patients who are not candidates for resective epilepsy surgery. In Saudi Arabia, VNS device implantation is being performed since 2008 by several comprehensive epilepsy programs, but with variable protocols. Therefore, to standardize the use of VNS, a task force was established to create a national consensus. This group consisted of epileptologists, epilepsy surgeons and a VNS nurse coordinator working in comprehensive epilepsy centers and dealing with refractory epilepsy cases. The group intensively reviewed the literature using Medline, EMBASE, Web of Science and Cochrane Library, in addition to physician's manual. Evidence is reported as three stages: preimplantation and patient selection, a perioperative phase involving all stakeholders and post-operative care with specific programming pathways.