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AHI — the Apnea-Hypopnea Index — is the average number of breathing events per hour of use. It’s the headline number your machine reports each night and the one clinicians watch most. Apnealytics charts it over time and breaks it down so you can see not just how many events, but what kind.
Machine-estimated AHI is not the same as a diagnostic sleep study. It’s excellent for tracking trends over time, not for diagnosing or grading disease. Bring the trends to your clinician rather than self-diagnosing from them. Apnealytics is a tracking and coaching tool, not a medical device.

The bands

On therapy, most people aim for an AHI under 5. Apnealytics bands each night so a glance tells you where it sits:
A single high night is usually just noise. A sustained shift over many nights is what’s worth a conversation with your clinician.

The event types behind the number

Your machine estimates several kinds of event and adds them up into AHI. Apnealytics splits them out so two nights with the same AHI but different make-ups look different:
The airway physically collapses and blocks airflow. The obstructive apnea index (OAI) counts these per hour.
The brain briefly stops sending the signal to breathe, so there’s no effort to breathe at all. The central apnea index (CAI) counts these per hour.
Partial narrowings that reduce — but don’t fully stop — airflow. The hypopnea index (HI) counts these per hour.
Events the machine couldn’t confidently sort into the categories above. The unclassified apnea index (UAI) captures these.
Apnealytics breaks AHI into these components on the Explore views, so you can see whether a change in your number is coming from obstructive events, central events, or hypopneas.

Read leak first

Before reading events on any night, glance at the leak. A high-leak stretch makes AHI unreliable, because air escaping the mask distorts what the machine can measure. If a night’s AHI looks surprising, check whether leak was high that night — see Metrics explained.
The in-app Knowledge Hub article “Understanding Your AHI” covers this in a three-minute read, and every page that interprets numbers carries the not-a-diagnosis reminder.