The AHI is measured during a sleep study and can help determine which treatments are best suited for you.
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What Is the Apnea-Hypopnea Index (AHI)?
When these happen, your blood oxygen will drop, leading tohypoxia.
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What Is an AHI Used For?
They also can detect changes in the blood oxygen levels and when hypoxia occurs.
The test begins the moment you fall asleep until the time you wake up the next morning.
Verywell / Laura Porter
Associated Tests
A test similar to the AHI is the respiratory-disturbance index (RDI).
Verywell / Laura Porter
What’s a Good Goal for AHI?
The AHI score indicates the average number of apnea and hypopnea events per hour.
Lower scores are better than higher scores.
With that said, the goals and interpretations can differ for adults and children.
Kids with an AHI of 2 or greater are typically referred for treatment.
Target AHI Goals
An ideal AHI for adults is fewer than five events per hour.
Some sleep specialists aim for one or two events per hour as the “safe zone.”
Childrens sleep is analyzed with stricter criteria.
More than one event per hour of sleep is considered abnormal.
Can You Have Sleep Apnea When Using CPAP?
The AHI is most commonly used to determine if CPAP is needed and how effectively it is working.
However, a CPAP machine may not prevent sleep apnea entirely.
It depends, in part, on the pressure set by your sleep specialist.
Modern CPAP machines are designed to track the number of breathing events you have each night.
Some can even be set up to share the results with your healthcare provider.
Make note of anything that may have happened or anything you may have taken the night before.
Over time, a pattern may emerge that reveals the underlying cause.
Simply changing the CPAP pressure without investigation can hurt more than it helps.
If you turn the pressure up too high, for example,central sleep apneacan occur.
This happens when your brain doesn’t tell you to breathe during sleep.
During your initial sleep study, you’ll receive a baseline AHI score.
That score will be used along with other tests to find the best treatment options for you.
Modern CPAP machines are able to calculate your AHI on a nightly basis.
This can inform you if sleep apnea is still occurring.
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