Accepted March 1, 2003.
Effects of Vagus Nerve Stimulation on Sleep-related Breathing in Epilepsy Patients
Article first published online: 19 JUN 2003
Volume 44, Issue 7, pages 930–935, July 2003
How to Cite
Marzec, M., Edwards, J., Sagher, O., Fromes, G. and Malow, B. A. (2003), Effects of Vagus Nerve Stimulation on Sleep-related Breathing in Epilepsy Patients. Epilepsia, 44: 930–935. doi: 10.1046/j.1528-1157.2003.56202.x
- Issue published online: 19 JUN 2003
- Article first published online: 19 JUN 2003
- Vagus nerve stimulator;
- Obstructive sleep apnea.
Summary: Purpose: To describe the effects of vagus nerve stimulation (VNS) on sleep-related breathing in a sample of 16 epilepsy patients.
Methods: Sixteen adults with medically refractory epilepsy (nine men, seven women, ages 21–58 years) underwent baseline polysomnograms (PSGs). Three months after VNS therapy was initiated, PSGs were repeated. In addition, patient 7 had a study with esophageal pressure monitoring, and patient 1 had a continuous positive airway pressure (CPAP) trial.
Results: Baseline PSGs: One of 16 patients had an apnea–hypopnea index (AHI) >5 (6.8). Treatment PSGs: Five of 16 patients had treatment AHIs >5. Respiratory events were more frequent during periods with VNS activation (on-time) than without VNS activation (off-time; p = 0.016). Follow-up studies: Esophageal pressure monitoring in patient 7 showed crescendos in esophageal pressure during VNS activation, supporting an obstructive pattern. The CPAP trial of patient 1 showed that all respiratory events were associated with VNS stimulation at low CPAP levels. They were resolved at higher CPAP levels.
Conclusions: Treatment with VNS affects respiration during sleep and should be used with care, particularly in patients with preexisting obstructive sleep apnea. The AHI after VNS treatment remained <5 in the majority of patients and was only mildly elevated (<12) in five patients. In one patient, CPAP resolved VNS-related respiratory events.