One of the most interesting parts of my work is being involved in the development and evaluation of treatments for snoring and obstructive sleep apnea. I have had the opportunity to work with many established and startup companies in their hard work creating and testing new approaches,and I pride myself on being a harsh critic, playing devil’s advocate as I look to identify the potential problems with these ideas and scrutinize data from clinical trials.
Of course, there are many companies with whom I have not worked, and I try to follow their work as closely as possible from a distance. One such company is Apnicure, who has developed a device (sold as Winx) that treats obstructive sleep apnea using suction through a mouthpiece to pull forward structures inside the mouth and throat. The mouthpiece is placed loosely over the upper teeth and has a suction port in the back, next to the soft palate. The mouthpiece does not hold the lower jaw forward like oral appliances–and therefore avoids the potential side effects of TMJ problems, tooth movement, and tooth pain that oral appliances can cause. Instead, a suction pump that rests next to an individual’s bed is connected to the device with a thin tubing (see image below from the company’s website). The idea is creative and clever, as it is almost the opposite of positive airway pressure therapy. If it worked well, this could be a powerful and important addition to sleep apnea treatment.
Does Winx work to treat sleep apnea?
Unfortunately, studies show that it does not work very well for many patients. A 2013 study from Dr. Ian Colrain from SRI Biosciences and colleagues published in the medical journal Sleep Medicine showed that only about 1 in 3 patients (32%, or 20/63) had a substantial improvement in their sleep apnea. The median (somewhat similar to an average) number of times per hour with blockage in breathing (apnea-hypopnea index) improved from 27.5 to about 14; there was an improvement in sleepiness and quality of life, although the quality of life changes were somewhat small. The Winx has some advantages, in that it does not require surgery and has low risks (although some patients cannot tolerate it due to discomfort), but these results are not good enough to recommend it for widespread use.
These results were disappointing and confusing, as it was expected that applying suction to the tongue and soft palate would be more beneficial. This month, an article published in the medical journal Sleep provides an explanation for the less than ideal results. In a series of 15 participants, Dr. Richard Schwab from the University of Pennsylvania and colleagues performed MRI studies of the head and neck before and after placement of the Winx device to learn more about how the device was working. They showed that the device opened the area behind the soft palate (what I call the Palate Region on my website) but actually narrowed the space for breathing behind the tongue (Tongue Region).
The Way Forward for Winx and Sleep Apnea Treatment
With this study, the suboptimal outcomes reported in previous Winx studies makes sense. Everything we know about treating different areas of the nose and throat in snoring and sleep apnea, including my own research on drug-induced sleep endoscopy, suggests that opening the Palate Region but closing the Tongue Region does not work well for most patients with sleep apnea. Apnicure’s next step is to improve the device design, and it is reassuring that Apnicure recently added to their solid team of experts by hiring Dr. David White as Chief Scientific Officer. David is one of the world’s leaders in the factors that cause sleep apnea and has been a gracious, supportive, and invaluable mentor to me (and so many others) over the past decade. I look forward to Apnicure’s efforts to do everything possible as they attempt to improve their approach and achieve better results.