Laryngeal motility alteration: A missing link between sleep apnea and vagus nerve stimulation for epilepsy

Epilepsia. 2016 Jan;57(1):e24-7. doi: 10.1111/epi.13252. Epub 2015 Nov 20.


This study aimed to evaluate the prevalence and the relationship of sleep breathing disorders (SBDs) and laryngeal motility alterations in patients with drug-resistant epilepsy after vagus nerve stimulator (VNS) implantation. Twenty-three consecutive patients with medically refractory epilepsy underwent out-of-center sleep testing before and after VNS implantation. Eighteen eligible subjects underwent endoscopic laryngeal examination post-VNS implantation. Statistical analysis was carried out to assess an association between laryngeal motility alterations and the onset/worsening of SBDs. After VNS implantation, 11 patients showed a new-onset mild/moderate SBD. Half of the patients already affected by obstructive sleep apnea (OSA) showed worsening of SBD. All of the patients with a new-onset OSA had a laryngeal pattern with left vocal cord adduction (LVCA) during VNS stimulation. The association between VNS-induced LVCA and SBD was statistically significant. This study suggests an association between VNS and SBD, hinting to a pivotal role of laryngeal motility alterations. The relationship between SBD and VNS-induced LVCA supports the need to routinely investigate sleep respiratory and laryngeal motility patterns before and after VNS implantation.

Keywords: Drug-resistant epilepsy; Sleep breathing disorders; Vocal cord dysfunction.

MeSH terms

  • Adult
  • Aged
  • Epilepsy / therapy*
  • Esophageal Motility Disorders / etiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Polysomnography
  • Sleep Apnea, Obstructive / etiology*
  • Statistics, Nonparametric
  • Vagus Nerve Stimulation / adverse effects*
  • Vocal Cords / physiopathology*