← All explanationsApnoea–hypopnoea index

What does AHI mean on a sleep report?

AHI is the average number of apnoeas and hypopnoeas recorded per hour of sleep. It helps classify sleep-disordered breathing. It does not fully describe how a person feels or determine treatment on its own.

For training & practice ↓

Fictional person with an airflow sensor, chest belt and finger sensor illustrating respiratory testing; no measurement result or patient finding. — Fictional testing example · no AHI value depicted

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Count defined events

Apnoea means near-complete interruption of airflow; hypopnoea is a relevant reduction according to scoring rules.

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Check the time denominator

A laboratory study measures sleep time. Home tests without sleep staging often use a different reference period, so numbers are not freely interchangeable.

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Read the whole report

Oxygen drops, daytime sleepiness, other conditions and symptoms also matter. A number alone does not select an oral appliance.

Watch the short explanation ↓

At a glance

Where found?

In an interpreted sleep report.

Enough alone?

No; symptoms and other measurements matter.

Dental relevance?

When considering a mandibular advancement appliance.

Knowledge in motion

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Silent educational film with German on-screen text and simplified teaching images. Not a patient case or a promised treatment outcome. The full English explanation is available below.

Read the film text in English

Count defined events
Apnoea means near-complete interruption of airflow; hypopnoea is a relevant reduction according to scoring rules.
Check the time denominator
A laboratory study measures sleep time. Home tests without sleep staging often use a different reference period, so numbers are not freely interchangeable.
Read the whole report
Oxygen drops, daytime sleepiness, other conditions and symptoms also matter. A number alone does not select an oral appliance.

Often confused

AHI versus oxygen saturation

AHI counts defined breathing events. Oxygen saturation is a different measurement that contributes to assessment.

Quick answers

Can my watch reliably determine AHI?

A consumer watch does not replace medically interpreted sleep testing.

Is a low value always reassuring?

No. Testing method, actual sleep and persistent symptoms need consideration.

Can I choose treatment from the number?

No. A sleep clinician interprets the findings; dental examination may then assess suitability for an appliance.

At the practice

For a personal discussion

Editorially suggested question to discuss with Dr Niusha Barahmand Pour:

Which information from my sleep report is needed to assess an appliance?

An existing sleep report helps discussions about a possible dental appliance.

Discuss an appliance questionAppointment selection at Doctolib

Meet Dr. Niusha Barahmand Pour ↗

Learning layer for training & practiceUnderstand terminology and deepen knowledge

Apnoea: Near-complete airflow interruption.
Hypopnoea: Reduced airflow meeting scoring criteria.
Index: A measure relative to a unit of time.

Make the distinction

AHI counts defined breathing events. Oxygen saturation is a different measurement that contributes to assessment.

Knowledge questionWhat does AHI count?

For learning, not for assessing personal symptoms. Your answer is not stored or sent.

Breathing events per hour of sleep.
Only snoring loudness.
The number of dental appliances.

View answer

Breathing events per hour of sleep.

Interpretation also requires the testing method and other findings.

Sources and context

Editorial research: 2026-11-02. General information, not an individual diagnosis or treatment recommendation. Teaching illustrations are simplified and do not depict a patient case.