Hypoglossal Nerve Stimulation Improves Sleep Apnea in CPAP-Intolerant Patients

By Marilynn Larkin

October 04, 2019

NEW YORK (Reuters Health) - For patients with moderate-to-severe obstructive sleep apnea (OSA) who can't tolerate a continuous positive airway pressure (CPAP) device, hypoglossal nerve stimulation may offer significant benefits, a pooled analysis found.

"Hypoglossal nerve stimulation is a relatively new therapy option for patients with OSA who cannot tolerate CPAP," Dr. David Kent of Vanderbilt University Medical Center in Nashville told Reuters Health by email. "This study is the first to pool data across multiple cohorts, and the results support the significant clinical improvements previously observed in measures of disease severity, daytime sleepiness, and quality of life."

"Older and lighter individuals seem to derive the greatest benefit from treatment," he said, "but younger and heavier patients can experience significant clinical improvements as well, when appropriately selected. The mechanisms underlying these differences deserve further study."

Dr. Kent and colleagues pooled data from three prospective cohorts and one retrospective observational cohort comprising 584 adults (mean age, 58.5; 81% men) with moderate-to-severe obstructive sleep apnea who could not tolerate CPAP.

As reported online September 26 in JAMA Otolaryngology-Head and Neck Surgery, the mean preoperative apnea-hypoxia index (AHI) was 33.8 events/h; the mean Epworth Sleepiness Score (ESS) was 11.8 on a scale of 0 to 24 (with higher scores indicating greater sleepiness); and the mean Functional Outcomes of Sleep Questionnaire (FOSQ) score was 13.9 on a scale of 5 to 20 (with lower scores indicating greater dysfunction).

Overall, postoperatively, the AHI decreased by a mean of 25.2 events/h at six months and by 16.5 events/h at 12 months.

Surgical success, defined as a decrease in AHI by at least 50%, and to below 20 events/hour at their last evaluation, was achieved in 450 patients (77.1%).

The ESS score decreased by a mean of 4.6 points at six months and 5.2 points at 12 months. At their last evaluation, 437 patients (75.3%) had an ESS score less than 10, i.e., in the normal range.

Further, FOSQ scores increased by a mean of 3.7 points at six months, and 3.4 points at 12 months. At the final evaluation, 55.9% reported an FOSQ score greater than 17.9.

Greater improvement in postoperative AHI was associated with a higher preoperative AHI, older age, and lower body mass index.

Summing up, the authors state, "Hypoglossal nerve stimulation demonstrated clinically significant improvements in obstructive sleep apnea severity, daytime sleepiness, and sleep-related quality of life."

Dr. Kent noted, "Patient preference is (also) a consideration in treating OSA, as there are a variety of different therapy options available for those unable to tolerate CPAP. Each medical and surgical option comes with its own odds of success and potential for side effects. Hypoglossal nerve stimulation appears to strike a reasonable balance between the two for many patients."

"Comorbid conditions such as significant cardiac or lung disease may affect eligibility if severe enough, so patients should consult closely with their sleep medicine physician and surgeon to determine what options may be appropriate for them," he concluded.

The study findings are "certainly true," commented Dr. Deborah Cappell, Director of Sleep Medicine at NewYork-Presbyterian Lawrence Hospital.in Bronxville, New York. "However... there are weight restrictions on patients who can be considered for this treatment - generally, a BMI less than 32."

"Given that it involves implanting a nerve stimulator into the body, it is not a first-line therapy," she told Reuters Health by email. "A drug-induced sleep endoscopy (is required) to evaluate the type and site of airway collapse to see if the patient is a candidate. It (also) requires turning the device on at bedtime and off in the morning."

One coauthor received funds from Inspire Medical Systems, which produces a hypoglossal nerve stimulator and contributed data for the study at no charge.

SOURCE: http://bit.ly/2nJonbm

Otolaryngol Head Neck Surg 2019.