Stages of Sleep Apnea

Obstructive sleep apnea can range from mild to severe, based on a measurement system called the apnea-hypopnea index (AHI). The AHI measures the number of breathing pauses that you experience per hour that you sleep.
Obstructive sleep apnea is classified by severity:
- Severe obstructive sleep: apnea means that your AHI is greater than 30 (more than 30 episodes per hour)
- Moderate obstructive sleep apnea: means that your AHI is between 15 and 30
- Mild obstructive sleep apnea: means that your AHI is between 5 and 15