VNS for Partial Seizures
(1998)Objective
To evaluate the efficacy and safety of vagus nerve stimulation (VNS) as adjunctive therapy in patients with medically refractory partial-onset seizures.
Study Summary
• In this multicenter, randomized active-control trial, high-frequency VNS significantly reduced seizure frequency and improved global well-being compared to low-frequency stimulation.
Intervention
High vs. low stimulation VNS delivered via implanted neurostimulator in patients with stable AED regimens.
Inclusion Criteria
Patients aged 12–65 with ≥6 partial-onset seizures/month, on 1–3 AEDs, and no recent status epilepticus or epilepsy surgery.
Study Design
Arms: High-Stimulation VNS vs. Low-Stimulation VNS
Patients per Arm: High: 94; Low: 102
Outcome
• Seizure reduction: High −27.9%, Low −15.2% (p=0.04). • Partial seizures with awareness alteration: High −26.6%, Low −13.4% (p=0.03). • ≥75% reduction: High 10.6%, Low 2.0% (p=0.015). • Global well-being scores significantly higher in high-VNS group (mean diff by interviewer rating: 4.0 mm, p=0.02). • Adverse events: Voice alteration (66.3% vs. 30.1%), dyspnea (25.3% vs. 10.7%), pharyngitis (34.7% vs. 25.2%). • No significant impact on autonomic, cardiac, or pulmonary function.