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Definition of AHI


Updated May 22, 2014

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Apnea-hypopnea index, or AHI, is an index used to assess the severity of sleep apnea based on the total number of complete cessations (apnea) and partial obstructions (hypopnea) of breathing occurring per hour of sleep. These pauses in breathing must last for 10 seconds and are associated with a decrease in oxygenation of the blood. In general, the AHI can be used to classify the severity of disease (mild 5-15, moderate 15-30, and severe greater than 30).

Also Known As: Apnea-Hypopnea Index, Respiratory Disturbance Index or RDI
My AHI was quite elevated, but it has greatly improved with treatment.
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