Understand Your Sleep Apnea Numbers & the Reading on Your CPAP Machine

Sleep Apnea Numbers at a Glance

According to the American Sleep Association, around 70 million Americans suffer from a sleep disorder, and approximately 95 percent of those affected remain undiagnosed and untreated. Obstructive sleep apnea (OSA) is one of the most common sleep disorders, yet it’s also one of the most underdiagnosed. In the US, just under half (48%) of the people surveyed reported snoring problems—the biggest indicator of obstructive sleep apnea. More than 50 percent of the diagnosed cases of sleep apnea occur in adults 40 and over. 

Sleep apnea numbers show that around 25 million US adults have been diagnosed with OSA. However, many people remain undiagnosed, putting their health at risk. Sleep deprivation lowers productivity, negatively impacts mood, and increases risk for accidents while driving. Over time, chronic sleep deprivation increases your risk of stroke and other serious health conditions

Your sleep apnea numbers will help your sleep specialist determine the most effective treatment for you. Sleep apnea is most commonly treated by prescribing a CPAP machine—Continuous Positive Airway Pressure or another device to help patients maintain normal airflow during sleep. Sleep apnea numbers are usually determined during a sleep study to measure the number of sleep apnea events per hour. The numbers help the sleep specialist customize the treatment program and average CPAP pressure for each individual.

AHI Meaning: What It Is & It’s Importance

Sleep apnea and hypopnea are both sleep breathing disorders. The Apnea-Hypopnea Index, or AHI, measures the number and severity of sleep apnea events per hour. Apneas indicate a blockage of air. Apneas are often due to a severe narrowing or total collapse of the sleeper’s throat that causes an obstruction in airflow to the lungs. The apnea results in sleep disruptions as the sleeper wakes intermittently to gasp for air. Hypopneas are incidents of shallow breathing that indicate a partial blockage of the airflow. Each apnea and hypopnea event must have a duration of at least 10 seconds to be counted in the index. AHI is calculated by dividing the number of events by the number of hours of sleep to determine whether a patient will require CPAP therapy.

The AHI Sleep Apnea Scale

<5 = normal sleep function

5-15 = mild sleep apnea

15-30 = moderate sleep apnea

>30 = severe sleep apnea

Common CPAP Machine Readings

Most CPAP machines measure:

  • AHI
  • Pressure
  • Leak
  • Usage

Pressure Reading

CPAP therapy offers different pressure settings. Newly diagnosed OSA patients will require a titration study in order to find the ideal level of pressure required to maintain an open airway during sleep. For most people, CPAP pressure is set between 6 and 14 cmH2O, with an average of 10 cmH2O. The majority of CPAP devices have pressure settings that max out at 20 cmH2O. Your sleep specialist will help you determine what specific level is right for you during your titration study. Over time, your CPAP device pressure may require adjusting, so consult your doctor or sleep specialist at Valley Sleep Center for guidance.

Leak Reading

A small amount of air leaking from the mask is perfectly normal and is determined by the manufacturer of the mask. It’s called the “intentional link” value. If your mask is 6-9 months old and begins leaking, you should consider replacing it. When a new mask is leaking, it’s often due to an incorrect fit. Your sleep specialist can help you find the right mask and fit to maximize your comfort during sleep. To replace your current mask, have your mask fitted, or any other CPAP machine needs, look no further than Valley Sleep Therapy.

Usage Reading

If you have OSA, using your CPAP machine nightly is essential. Your usage threshold is the minimum amount of time you must use your CPAP device in order to be compliant with your prescribed treatment plan. The usage measurement is a factor that insurance companies track to assess treatment compliance for coverage. For instance, Medicare mandates that all durable medical equipment providers show that the equipment was used for the set minimum number of hours, so all Medicare patients would need to use a CPAP machine that tracks compliance.

CPAP usage is determined by how long you wear your CPAP mask each night. One important note: most CPAP devices can tell the difference when the mask is actually on the person versus just turning it on but not wearing it, so don’t be tempted to cheat! If your CPAP mask is uncomfortable or leaks too much, consult with your sleep specialist for a proper fitting.

Whether you’re just beginning CPAP therapy or you’re a seasoned veteran, understanding your sleep apnea numbers and finding the right CPAP device, mask, cleaning supplies, and accessories for you is a critical component of treatment. If you’re not comfortable, you’re less likely to maintain compliance with your therapy, putting your health at risk and the possibility of increased sleep apnea events per hour. Contact Valley Sleep Therapy for expert fitting and guidance. Call us at 480-361-0124, or send an email to info@valleysleeptherapy.com.