American Board of Internal Medicine (ABIM) Certification Practice Exam

Which AHI level is indicative of severe obstructive sleep apnea?

1. 5

2. 15

3. 25

4. 30

The correct answer is: 30

Severe obstructive sleep apnea (OSA) is characterized by an Apnea-Hypopnea Index (AHI) of 30 or higher. The AHI is a measure used to quantify the severity of sleep apnea based on the number of apneas (complete stoppages of breathing) and hypopneas (shallow breathing or reduced airflow) that occur during sleep, averaged per hour. An AHI of 30 indicates that on average, a person experiences 30 episodes of apneas or hypopneas each hour of sleep. This level of severity is associated with significant health risks, including cardiovascular complications, daytime fatigue, and impaired quality of life, making it crucial for diagnosis and treatment. In contrast, lower AHI values suggest less severe forms of sleep apnea. For example, an AHI of 5 is generally considered mild, while an AHI of 15 suggests moderate sleep apnea. Understanding these classifications helps guide appropriate interventions and management approaches for patients suffering from varying degrees of OSA.