Enter the total number of apnea events and hypopnea events, and the total sleep time into the calculator to determine the Apnea Hypopnea Index.

## Apnea Hypopnea Index Formula

The following formula is used to calculate the Apnea Hypopnea Index (AHI).

AHI = (A + H) / T

Variables:

- AHI is the Apnea Hypopnea Index (events per hour)
- A is the total number of apnea events
- H is the total number of hypopnea events
- T is the total sleep time (hours)

To calculate the Apnea Hypopnea Index, add the total number of apnea events to the total number of hypopnea events. Then, divide this sum by the total sleep time in hours. The result is the Apnea Hypopnea Index, which indicates the severity of sleep apnea.

## What is an Apnea Hypopnea Index?

The Apnea Hypopnea Index (AHI) is a standard tool used to measure the severity of sleep apnea. It calculates the average number of times per hour of sleep that a person’s breathing stops (apnea) or becomes dangerously shallow (hypopnea). A higher AHI indicates more severe sleep apnea, with a score of 5-15 indicating mild sleep apnea, 15-30 indicating moderate sleep apnea, and a score over 30 indicating severe sleep apnea.

## How to Calculate Apnea Hypopnea Index?

The following steps outline how to calculate the Apnea Hypopnea Index (AHI).

- First, determine the total number of apnea events (A).
- Next, determine the total number of hypopnea events (H).
- Next, determine the total sleep time in hours (T).
- Next, gather the formula from above: AHI = (A + H) / T.
- Finally, calculate the Apnea Hypopnea Index (AHI).
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem:**

Use the following variables as an example problem to test your knowledge.

total number of apnea events (A) = 10

total number of hypopnea events (H) = 5

total sleep time in hours (T) = 8