Novel hypoglossal nerve stimulation device improves OSA
A bilateral hypoglossal nerve stimulation system reduced severity of obstructive sleep apnea and improved quality of life without device-related complications, according to a study published in the European Respiratory Journal.
The researchers enrolled 27 patients (63% men; mean age, 55.9 years; mean BMI, 27.4 kg/m2) in the prospective, open-label, single-arm BLAST OSA study conducted at eight centers in Australia, France and the United Kingdom. Patients qualified for inclusion if they were aged 21 to 75 years, did not tolerate positive airway pressure treatments and had a BMI of 32 kg/m2 or less, an obstructive apnea-hypopnea index (AHI) of 20 to 60 events per hour and combined central and mixed AHI of less than 10 events per hour, no positional OSA and absence of soft palate complete concentric collapse during drug-induced sleep endoscopy.
Of those enrolled, 22 patients were implanted with the novel device that delivers bilateral hypoglossal nerve stimulation (Genio system, Nyxoah).
The system includes a stimulation unit that is surgically implanted in the submental region and positioned over the genioglossus muscles with stimulating electrodes proximate to the left and right hypoglossal nerve branches. The implanted stimulation unit stimulates the nerves by receiving energy pulses transmitted transdermally from an external activation unit that can be attached to an adhesive disposable patch and is placed under the chin before going to sleep. Patient-specific stimulation parameters are preprogrammed into the activation unit and are adjusted wirelessly.
In the study, the device was activated 4 to 6 weeks after implantation and titrated at follow-up visits at 2, 3 and 4 months. The researchers programmed the devices and made adjustments during awake titrations and during in-lab polysomnography studies. Outcomes, including the primary outcomes of the incidence of device-related serious adverse events and change in the AHI, were measured at 6 months.
At 6 months, no device-related serious adverse events occurred. Three participants experienced four procedure-related serious adverse events, including surgical site infections requiring explantation of the device and impaired swallowing leading to a 1-day prolongation of implantation-related hospitalization. All were resolved without further problems, according to the researchers. The most commonly reported procedure-related nonserious adverse events included impairment or painful swallowing, dysarthia, hematoma and swelling or bruising around the incision site. The most commonly reported device-related nonserious adverse event was local skin irritation due to the use of the disposable patch.
Also at 6 months, AHI decreased from 23.7 to 12.9 events per hour (P < .001), with a mean individual percentage decrease of 47.3% and the 4% oxygen desaturation index — the main secondary outcome — decreased from 19.1 to 9.8 events per hour (P < .001). Results also showed improvements in daytime sleepiness, as measured by the Epworth Sleepiness Scale (P = .01), and sleep-related quality of life, as measured by the Functional Outcomes of Sleep Questionnaire (P = .02).
Additionally, the researchers noted that the number of bed partners reporting loud, very intense snoring or leaving the bedroom due to partner snoring decreased from 96% to 35%.
More than 90% of patients reported using the device more than 5 days per week and more than three-quarters reporting using the device for more than 5 hours per night.
“Given the results of this study, the limitations of the existing treatment options, and the negative health and well-being consequences of leaving significant OSA untreated, the Genio system may be considered as a valid treatment option to treat OSAs in a targeted population,” the researchers wrote. – by Melissa Foster
Disclosures: This study was funded by Nyxoah SA. Eastwood reports receiving support for undertaking trials from Nyxoah SA, Oventus Pty Ltd and Zelda Therapeutics. Please see the study for all other authors’ relevant financial disclosures.