Continuous Positive Airway Pressure (CPAP) therapy effectively manages sleep apnea, but users sometimes observe an increase in their “events per hour,” also known as the Apnea-Hypopnea Index (AHI). The AHI represents the average number of times per hour that breathing partially or completely stops during sleep. An increase in this number indicates the therapy might be less effective, pointing to potential issues with equipment, lifestyle, or underlying health conditions.
Checking Your CPAP Equipment
One common reason for an increase in AHI is issues with the CPAP equipment itself. A poorly fitting mask can cause air leaks, which reduce the effective pressure delivered by the machine and can lead to more breathing events. A mask that is too loose, has worn-out cushions, or is the incorrect size for your face can result in air escaping, especially during sleep position changes. Regularly checking the mask seal, replacing cushions every 2-4 weeks, and replacing the entire mask every three months can help maintain an effective seal.
Proper machine maintenance also plays a role in consistent therapy. Clogged filters can restrict pressure delivery, and dirty or damaged tubing (e.g., kinks, cracks) can impede airflow. Regular cleaning of the mask cushion daily, humidifier water tub daily, and tubing weekly with mild soap and water is recommended. Users should also examine tubing every three months for wear or damage.
Incorrect settings for the humidifier and heated tubing can cause condensation, often referred to as “rainout,” which might disrupt sleep or lead users to adjust their mask, potentially breaking the seal. Adjusting humidity levels or using heated tubing can help prevent this discomfort. While pressure settings might need adjustment, this is typically a change made by a healthcare professional rather than a user.
Lifestyle and Health Considerations
Personal habits and health changes can also influence CPAP effectiveness and lead to a higher AHI. Significant weight gain can increase the severity of sleep apnea by adding tissue around the airway, which may necessitate a change in CPAP pressure to maintain an open airway. Conversely, weight loss can sometimes reduce the severity of sleep apnea and may lead to a need for lower CPAP pressure.
Sleeping position can affect breathing patterns during sleep. For many individuals, sleeping on the back can worsen sleep apnea because gravity allows the tongue and soft tissues to fall backward, obstructing the airway. Side sleeping is often recommended as it helps keep the airway clearer.
Substances like alcohol and sedatives relax throat muscles, making airway collapse more likely and increasing the frequency of breathing events. It is generally advised to limit alcohol intake, especially in the hours leading up to bedtime, to minimize its impact on airway muscle tone. Nasal congestion from allergies, colds, or other respiratory illnesses can make it difficult to breathe through the nose, potentially leading to mouth breathing and reducing CPAP effectiveness, especially with nasal masks. Using saline sprays or a humidifier can help manage nasal congestion.
Certain medications, particularly those with sedative effects, can also relax upper airway muscles and worsen sleep apnea. It is advisable to discuss all medications with a healthcare provider to understand their potential impact on sleep and breathing. As people age, changes in the body can also affect sleep apnea severity, and older adults may experience a natural increase in AHI.
Understanding Your Data and Seeking Support
CPAP machines record data that can provide valuable insights into therapy effectiveness. It is beneficial to monitor trends in AHI over time rather than focusing on isolated nightly fluctuations, as some variability is normal. Reviewing data points such as usage time, leak rates, and the number of apnea and hypopnea events can help identify patterns or potential issues with therapy. Many machines offer detailed reports through their displays or associated apps.
When a persistent increase in AHI occurs despite troubleshooting equipment or adjusting lifestyle factors, it is appropriate to contact a sleep specialist. Professional intervention is necessary for scenarios such as consistently high AHI readings above the acceptable range (typically over 5 events per hour), significant changes in overall health, or experiencing new or returning symptoms of sleep apnea.
CPAP therapy often requires ongoing monitoring and adjustments by a healthcare provider to ensure its continued effectiveness. Regular follow-up appointments allow a specialist to evaluate your data, make necessary pressure changes, and address any new health or lifestyle factors that could be impacting your sleep apnea. This collaborative approach helps maintain optimal therapy and improve overall sleep quality.