Obstructive sleep apnea (OSA) requires treatment. The first line of therapy for OSA is the use of Continuous Positive Airway Pressure (CPAP) mask. Though effective, CPAP has its problems. The mask can be uncomfortable, the system itself is bulky and makes noise, and using CPAP requires some life adjustments.
Studies have shown that compliance with this therapy has been quite poor, with 15 percent of patients choosing to not even begin therapy once they are diagnosed with sleep apnea. Less than half of those who start therapy are found to maintain it a year later.
There are usually some clues that predict compliance. For example, maintaining treatment was more likely to be found in those who have “severe disease accompanied by symptoms of daytime somnolence (sleepiness).”
Since mask fit and comfort is a big deal, clinicians have wondered if a better mask might improve compliance. A study that aimed to answer this question was published in the Journal of Clinical Sleep Medicine. It compared the use of simple nasal mask to both a nasal mask with the addition of chin strap and an oro-nasal mask which covers the nose and the mouth area completely. The study looked at differences in efficacy, mask leak, patient adherence, and patient preference.
In this particular study there was no difference in adherence but there was a significant difference in the improvement in the Apnea Hypopnea Index (AHI) with both nasal masks over the or-nasal mask. The subjective feelings of comfort were also significantly better with the nasal mask over the oro-nasal masks. Let’s look at elements of each of the current available mask versions:
This mask in the shape of a triangle with the apex at the bridge of the nose and the base edge to the upper lip area covers the nose only.
Advantage: It can deliver higher pressures and it is a good match if someone moves around in their sleep a lot.
Disadvantages: The mask is difficult for those who have chronic sinusitis or nasal problems. The higher the pressure settings, the more likely there’s an associated increased inflammation and resultant closure in the nasal passages due to swelling. Wearing the nasal mask is also difficult for individuals with conditions such as a deviated septum and narrowed or enlarged turbinates inside the nasal mucosa.
The nasal mask is also not a good match for mouth breathers. The air delivered through the nasal mask into the nose encounters resistance in the throat as it tries to keep the airway open and patent. Some of that air gets through because of the pressure and will succeed in opening the obstruction, but in the case of a mouth breather, some air escapes out through the mouth. This creates an unpleasant sensation of (pressured) air going in through the nose and coming out through the mouth. It can be a compliance deal breaker for mouth breathers.
The solution for this last issue is a nasal mask with a chin strap. The strap makes sure that the mouth essentially stays closed during sleep. It can work for some mouth breathers, while others may find it suffocating, especially if they also have abnormal nasal passages.
These are light masks that have small projections that go directly into the nostrils.
Advantage: They are small and do not interfere with vision – allowing the person to even wear glasses since the device doesn’t go over the bridge of the nose. Nasal pillows are good for people with excessive facial hair and beards. They allow easy movement and repositioning while sleeping through the night.
Disadvantage: This version is not a good match for patients requiring delivery of high pressures since the device can allow some air to leak and irritate the eyes.
Mouth breathers may encounter the same problems with this device that occurs with a nasal mask, so nasal pillows can also be used with a chin strap.
It’s important to note that the amount of pressure that an individual needs to eliminate the obstruction that results in their apnea differs from person to person, and it’s determined by titration of pressures during a sleep study.
Full face CPAP mask
This is the mask that encompasses nose and mouth. It is triangular-shaped like the nasal mask but the base ends at the lower jaw covering the mouth as well (hospital versions are a bit different and cover the entire face).
Advantage: This mask works well for mouth breathers and for those individuals who have nasal allergies and nasal obstruction from deformed septum and turbinates. These masks also seem to be well tolerated by patients who require high pressures because the flow of air is less direct to the nose.
Disadvantage: The mask is bulky and with frequent movements during sleep, high pressures may result in leakage of air. That can make it less effective in opening the throat.
This last consideration may explain why, in this particular study, there was a better improvement in the AHI in the group who used the nasal masks compared to those who used the oral full face mask. Compliance is everything, but less leakage is important too.
There are new products on the market made from newer materials that also makes contact with the skin less irritating. There is also a version that offers a connective mechanism that is flexible and easy to disconnect from the machine, when one goes to the bathroom. There are newer straps that go above the head and not through the sides of the mask, allowing people to sleep on their sides – a big consideration for many people who need and use CPAP.
There are two dominant companies that offer OSA and CPAP products:
Phillips-Respironics: Their newer products are DreamWear Gel Pillows and DreamWear Nasal CPAP.
ResMed: They offer AirFit CPAP and their version of nasal pillows and ResMed Mirage Liberty Hybrid Mask.
Each company’s products have their own unique proprietary features.
It’s crucial for people to recognize that OSA cause serious health consequences if left untreated. Compliance remains a serious challenge but must remain a top priority. Consideration of types of masks with patient comfort in mind is important, since sleep comfort is mask-dependent. Ironically, masks are actually the cheapest element in the treatment complex. The findings from the study should help to drive more individualized treatment and hopefully better compliance with treatment.