Efficacy and safety of using vagus nerve stimulation in patients with pharmacoresistant epilepsy in the Russian Federation: a multi-center retrospective observational program

Objective: to assess efficacy and safety of vagus nerve stimulation (VNS) in patients with pharmacoresistant epilepsy.Material and methods. A multi-center retrospective observational program was applied in patients with pharmacoresistant epilepsy by using vagus nerve stimulation for at least 2 years. There were enrolled 151 subjects, patient age on stimulator implantation varied from 5 to 65 years (24.4±13.1 years). Among them, subjects under 18 or at least 18 years of age comprised 58 (38.4%) and 93 (61.6%), respectively. Changes in rate and severity of major group epileptic seizures (highly disabling type) 24 months after VNS-therapy vs. baseline state as well as during 3-, 6-, 9-, 12-month follow-up were compared. There were assessed stimulator-related effects on VNS-therapy as well as patient quality of life 2 years after therapy. The dynamics of the frequency of all types of epileptic seizures was evaluated according to McHugh Outcome scale.Results. Mean epilepsy duration on stimulator implantation was 170.9±126.8 months, with maximum up to 666 months (55 years). Number of patients with dominant (disabling) seizures on implantation procedure comprised 136 (90.1%). Decline in dominant epileptic seizure rate by 50–99% was recorded in 91 patients (66.9%) 24 months after VNStherapy. Among such subjects were 41 patients (30.15%) featured with disabling seizures including 24 fully seizure free subjects (17.65%). Decreased rate of all group epileptic seizures by more than 50% (responders) was found in 52.9% cases, including subjects under 18 and adults in 63.9% and as few as 46.3% (pConclusion. Vagus nerve stimulation is an effective and safe auxiliary treatment method for therapy of pharmacoresistant epilepsy both in children and adults.