Implanted Device Reduces Sleep Apnea Episodes

Patients with obstructive sleep apnea (OSA) that used a new implanted device had an approximately 70% reduction in OSA severity, according to a new study.

Researchers at the University of Pittsburgh (Pitt, PA, USA), the University of Mannheim (Germany), and other institutions participating in the multicenter prospective stimulation therapy for apnea reduction (STAR) trial surgically implanted the device in 126 patients (83% men, mean age 54.5 years, mean body-mass index (BMI) 28.4) with OSA who had difficulty either accepting or adhering to continuous positive airway pressure (CPAP) therapy. The primary outcome measures were apnea-hypopnea index (AHI) and oxygen desaturation index (ODI).

For the study, the researchers used the Inspire upper airway stimulation (UAS) device, which was implanted in three areas: a stimulation electrode was placed on the hypoglossal nerve, which provides innervation to the muscles of the tongue; a sensing lead placed between rib muscles to detect breathing effort; and a neurostimulator implanted in the upper right chest, just below the clavicle bone. The device is designed to sense breathing patterns and deliver mild stimulation to a patient’s airway muscles to keep the airway open during sleep. The patients used a controller to turn on the device at night just before sleep.

The results showed that median AHI score at 12 months decreased by 68%, and the ODI score decreased by 70%; secondary outcome measures showed a reduction in the effects of OSA and improved quality of life; 86% of patients were still using the device every night at the one year mark. The AHI score was significantly higher (indicating more severe apnea) among the 23 participants in the therapy-withdrawal group, with ODI results showing a similar pattern. The rate of procedure-related serious adverse events was less than 2%. The results of the study were published on January 9, 2014, in the New England Journal of Medicine (NEJM).

“Inspire UAS therapy differs from other traditional sleep apnea devices and surgical procedures in that it targets the muscle tone of the throat rather than just the anatomy,” said coauthor assistant professor Ryan Soose, MD, of the Penn department of otolaryngology. “Two thirds of patients using the Inspire UAS therapy device had successful control of their OSA although even more reported improvement in snoring, daytime sleepiness and quality of life measures.”
The Inspire UAS device is a product of Inspire Medical Systems (Maple Grove, MN, USA), and is European Community (CE) marked.

Related Links:
University of Pittsburgh
University of Mannheim
Inspire Medical Systems