Long-term follow-up of 37 patients with refractory partial seizures treated with vagus nerve stimulation

Stimulation of the vagus nerve for the treatment of refractory seizures of partial onset has been studied in two pilot studies and one randomized, blinded, parallel study. Results from the controlled study have been promising, but more information is required regarding the long-term safety and efficacy of vagus nerve stimulation. A cohort of the first 37 patients to finish the controlled study was examined on a long-term basis. The response of patients at 1 year and 18 months of stimulation revealed that efficacy does not decrease over time. The system is well-tolerated, and no major adverse events occurred with long-term exposure to the stimulation. Normal device end of service occurred in a majority of the patients, with most choosing to have their generators replaced. This analysis demonstrates that stimulation of the vagus nerve for the treatment of refractory epilepsy manifested by seizures of partial onset continues to be safe and effective over extended periods of time.