Effects of vagus nerve stimulation on sleep-related breathing in epilepsy patients

Epilepsia. 2003 Jul;44(7):930-5. doi: 10.1046/j.1528-1157.2003.56202.x.


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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Airway Resistance / physiology
  • Anticonvulsants / therapeutic use
  • Combined Modality Therapy
  • Electric Stimulation Therapy* / adverse effects
  • Electric Stimulation Therapy* / instrumentation
  • Epilepsy, Complex Partial / physiopathology*
  • Epilepsy, Complex Partial / therapy
  • Epilepsy, Generalized / physiopathology*
  • Epilepsy, Generalized / therapy
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Myoclonic Epilepsy, Juvenile / physiopathology*
  • Myoclonic Epilepsy, Juvenile / therapy
  • Oxygen / blood
  • Polysomnography*
  • Prostheses and Implants
  • Pulmonary Ventilation / physiology*
  • Solitary Nucleus / physiopathology
  • Vagus Nerve / physiopathology*


  • Anticonvulsants
  • Oxygen