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Apnoea-hypopnoea index

Breathing tests · also printed as AHI, Apnoea hypopnoea index, Apnea-hypopnea index, AHI (/hr), Apnoea/hypopnoea index

Typical UK adult rangebelow 5 /hr

Below 5 per hour is typical; 5 to 15, 15 to 30 and above 30 are the bands sleep clinics print.

What this test measures

The AHI counts how many times per hour breathing stops or becomes very shallow during sleep. It is the main measure from a sleep study.

Why doctors request it

Used to assess sleep apnoea and to follow treatment with a mask (CPAP) or a mouthpiece.

What commonly pushes it up

Obstructive sleep apnoea
Sleeping on the back, alcohol and sedatives
Being overweight
Nasal blockage on the night

What commonly pushes it down

Weight loss
Effective CPAP or mouthpiece treatment
Sleeping on the side

Everyday reasons for a value outside the range

A single night can be unrepresentative
Home and hospital studies score slightly differently

About the sample

Overnight recording at home or in hospital.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.

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This is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.