Continuous positive airway pressure, or CPAP, is the most common treatment prescribed for obstructive sleep apnea. CPAP involves wearing a mask that fits into the nostrils, underneath or over the nose, or over the nose and mouth, through which pressurized air is delivered via tubing from a machine to keep the upper airway open during sleep.
CPAP is recommended by the American Academy of Sleep Medicine (AASM) as the initial treatment for moderate or severe obstructive sleep apnea, and in mild cases of obstructive sleep apnea when associated with insomnia, disrupted sleep, or excessive daytime sleepiness. When used consistently, and when treatment is effective, CPAP improves daytime sleepiness, quality of life, and it can have positive impacts on cardiac and metabolic health.
The effectiveness depends on using the device correctly and consistently, since obstructive sleep apnea is a chronic disease that requires long-term treatment. Most sleep doctors, myself included, recommend that patients with sleep apnea use their treatment whenever they sleep, in order to derive optimal benefit.
While there are many patients who love their CPAP machines and report the treatment to be life-changing, and are unable to sleep without CPAP, there are others who learn to accept and tolerate CPAP because they appreciate either the functional benefits (such as better mood and less daytime sleepiness) or medical improvements they get from using the device. However, many patients struggle with CPAP.
CPAP is not easy and there are common complaints
Despite the many potential benefits, CPAP adherence estimates from clinical data and insurance groups suggest that about 50% of CPAP users either do not reach minimum adherence criteria or discontinue the treatment. Each patient is unique and may have individual struggles with CPAP; however, there tend to be similar themes among users.
Some of the common complaints I hear from patients who have trouble tolerating CPAP include:
- Mask issues, including mask discomfort, skin irritation or marks, feelings of claustrophobia, or discomfort with the appearance of wearing a mask.
- Dryness, especially waking with a dry mouth.
- Removing the mask during sleep.
- Pressure intolerance, from either too much pressure or not enough pressure; trouble exhaling against the CPAP pressure; or swallowing air (aerophagia).
- Breathing that feels out of sync.
- Noise from the machine bothering the patient or their bed partner.
Troubleshooting issues with CPAP tolerance
First and foremost, patients should partner with their doctor and healthcare team. obstructive sleep apnea is a serious disease that warrants treatment. Before starting treatment, patients should be educated about obstructive sleep apnea, learn about all treatment options and new technologies, and know what to expect with CPAP.
Patients benefit from close clinical follow-up, including a review of data from their CPAP device (which may also be important for continued insurance coverage). Family and/or partner support is also important, as friends or family can help encourage and support CPAP use.
Other tips to improve adherence
- Behavioral and medication interventions. Cognitive behavioral therapy or short-term use of sleep medications can help people adjust to CPAP.
- The right mask. If the mask does not fit, the treatment may not work well. There are many mask sizes and types, including nasal masks that fit over or under the nose, nasal pillows that fit in the nostrils, full face masks that cover the mouth and nose, hybrid masks that sit under the nose and cover the mouth, and even helmet masks that cover the face. A mask fitting is advised when patients start treatment, and several fittings may be needed.
- Mouth breathing is another mask-related factor to consider. When a patient sleeps with their mouth open, the pressure from the CPAP leaks out the mouth. This causes dryness, and also prevents CPAP from keeping the upper airway open. Mask leak can also result in noise and mask removals during sleep. A mask that covers the mouth will probably be needed, though sometimes adding a chinstrap can keep the jaw closed and prevent mouth breathing.
- The right pressure. Some people require vastly different pressure when on their back vs. on their side, or in one sleep stage vs. another. While a pressure range can be helpful, if the range is too wide, the machine cannot adjust rapidly enough to meet the pressure requirements. Weight changes may also impact pressure requirements. Following device data and/or evaluating with a treatment sleep study in a sleep lab can help identify the best pressure.
- Address coexisting conditions. Some people use CPAP consistently, tolerate it, but are still sleepy. CPAP is not a substitute for inadequate sleep. Sleep apnea can coexist with other sleep problems that might contribute to daytime sleepiness. Sometimes CPAP is not tolerated because sleep is poor or fragmented due to other issues such as anxiety, PTSD, insomnia, poor sleep habits, or circadian disorders. These other problems need to be addressed.
- Consider alternative treatments. CPAP is the first-line treatment, but not the only treatment for obstructive sleep apnea. Consider combining treatments or pursuing an alternative treatment if CPAP is not tolerated or is not desired.
New CPAP innovations can help
A variety of technological advances may improve CPAP comfort and adherence. Some of these include:
- Heated humidification, a comfort intervention that can help with nasal congestion and dryness.
- Ramp-up features that allow the machine to start off at a low or minimal pressure as the patient adjusts and falls asleep.
- Expiratory pressure relief, where the pressure from the machine decreases slightly during exhalation, which is especially helpful when a higher pressure setting is needed to keep the airway open.
- Auto-titrating CPAP machines, which allow for a range of pressures to be set; the machine self-adjusts the pressure when it senses that more or less pressure is needed to keep the airway open. This is helpful for those who require higher pressures in one body position (back vs. side) or sleep stage (dream/REM sleep vs. nondream/NREM).
- Modems that allow the machine to transmit data (either cellular or by Wi-Fi), so both the patient and their doctor can determine the effectiveness of the treatment.
The bottom line
CPAP is an effective treatment for obstructive sleep apnea. If you are struggling with CPAP tolerance, do not give up, but rather talk to your clinician. Proper education, support, personalized troubleshooting, new technologies, and close clinical follow-up can improve adherence and optimize treatment outcomes.
(Melanie Pogach, MD, is a contributor to Harvard Health Publications.)