CPAP therapy is the primary treatment for Obstructive Sleep Apnea (OSA), delivering a steady stream of pressurized air that acts as an “air splint” to keep the airway open during sleep. If snoring persists after introducing a CPAP device, it signals that the therapy is not working optimally. This continued loud breathing requires troubleshooting, as it indicates a return of partial airway collapse or other issues. Finding the source of the noise is necessary for both quiet nights and effective treatment of the underlying sleep disorder.
Improper Mask Fit or Usage
A major reason for continued snoring is a mask that does not fit correctly, creating air leaks that significantly reduce the intended pressure inside the airway. When air escapes through the seal or the mouth, the pressure is no longer sufficient to fully splint the throat tissues open, allowing them to vibrate and produce the characteristic snoring sound. Checking the cushion size and the tightness of the headgear is the first step, ensuring the mask is snug without being overly restrictive.
Mouth breathing is a common form of air leakage, especially when using a nasal mask, as the pressurized air escapes through the open mouth instead of flowing into the lower airway. Switching to a full-face mask that covers both the nose and mouth, or incorporating a chin strap, can often resolve this issue and restore effective pressure delivery. Consistent usage for the entire sleep duration is also important because partial compliance leads to partial treatment, meaning the airway can still collapse and cause snoring during the hours the device is not worn.
Equipment maintenance can also impact the effectiveness of the therapy. Dirty air filters impede the machine’s ability to pull air efficiently, while worn-out mask cushions or tubing can compromise the seal or the overall airflow. Mask cushions lose their ability to seal properly over time and should typically be replaced every three to six months to maintain optimal performance and prevent pressure loss.
Pressure Settings and Calibration Needs
The pressure setting prescribed for a CPAP machine may be too low to effectively keep the upper airway open throughout the night, allowing the throat tissues to partially collapse and generate snoring vibrations. This often occurs if the user has experienced changes in health, such as significant weight gain, since the initial sleep study determined the pressure setting. Weight gain increases the amount of soft tissue around the neck, requiring a higher pressure to maintain airway patency.
A fixed-pressure CPAP machine delivers the same pressure level all night, which may be insufficient during periods of deeper sleep, such as Rapid Eye Movement (REM) sleep, when the throat muscles are most relaxed. Auto-adjusting Positive Airway Pressure (APAP) devices automatically vary the pressure moment-to-moment based on the user’s breathing needs. APAP can be more effective at maintaining airway openness and eliminating snoring across different sleep stages, dynamically responding to subtle airway resistance.
The Ramp Feature
The “ramp” feature allows the pressure to start low for comfort and gradually increase to the prescribed therapeutic level over a set period. If this ramp period is set too long or the starting pressure is too low, the airway may not be adequately supported during the early stages of sleep. This results in snoring until the full pressure is reached. Disabling the ramp feature or shortening the ramp time can sometimes eliminate snoring that occurs just as the user is falling asleep.
Non-Apnea Causes of Residual Snoring
While CPAP is highly effective at treating the airway collapses associated with Obstructive Sleep Apnea, it may not eliminate all sources of snoring, which is simply the vibration of respiratory structures. If the machine’s data indicates that apnea events are successfully suppressed, the residual snoring may be caused by factors unrelated to OSA severity.
Nasal Congestion and Anatomy
Nasal congestion from seasonal allergies, a cold, or anatomical issues like a deviated septum can cause turbulent airflow and loud vibrations high in the nasal passages. Even with the correct pressure, this upper airway congestion forces the air through a narrower space, generating noise that the CPAP is not designed to prevent. Using a heated humidifier or managing congestion with saline rinses or nasal sprays can help open these passages and reduce the vibrational noise.
Positional and Central Issues
Positional snoring is another common cause, as sleeping on the back can cause the tongue and soft palate to fall backward, partially obstructing the airway and creating a vibration. A rare but more complex issue is the development of Central Sleep Apnea (CSA), where the brain temporarily fails to signal the muscles to breathe, which is distinct from the physical obstruction of OSA. Persistent snoring despite optimal pressure settings might be a sign of a complex underlying condition requiring specialized treatment beyond standard CPAP.
When to Consult the Sleep Specialist
Before seeking medical intervention, users should check the CPAP machine’s usage data, often accessible via a smartphone app or an SD card, to confirm the device is being worn for the entire night. The most telling data point is the Apnea-Hypopnea Index (AHI), which measures the number of breathing disturbances per hour. A low AHI, typically below five, suggests the OSA is being treated effectively, and the snoring is likely a residual issue. If the AHI remains high or the user is still experiencing daytime fatigue, the therapy is not working, and professional help is warranted.
If troubleshooting the mask fit and usage compliance does not resolve the persistent snoring, the next step is to consult the sleep specialist to have the pressure settings reviewed. The specialist can remotely access the machine’s detailed data to check for excessive air leaks or periods where the prescribed pressure was insufficient. They can then safely adjust the pressure, or recommend a new titration study to establish a more appropriate setting based on current physiological needs.
For issues related to the physical equipment, contacting the durable medical equipment (DME) supplier is often the fastest way to address mask sizing, try different mask types, or replace worn-out parts that may be causing leaks. However, if the snoring is accompanied by choking, gasping, or a return of daytime sleepiness, it is imperative to schedule a follow-up appointment with the sleep specialist immediately. This is necessary to rule out serious issues like a complex sleep disorder or a significant change in the severity of the Obstructive Sleep Apnea.