An AHI greater than 30 episodes per hour indicates which level of sleep apnea?

• A. Mild sleep apnea
• B. Severe sleep apnea
• C. Normal sleep
• D. Moderate sleep apnea

Answer: (B)

The main idea is that sleep apnea severity is classified by how many breathing interruptions occur per hour of sleep, called the apnea-hypopnea index (AHI). When the AHI exceeds 30 events per hour, it is placed in the severe category, indicating a high frequency of apneas and hypopneas and significant sleep disruption. For context, normal is typically fewer than about 5 events per hour, mild ranges roughly from 5 to 15, and moderate is about 15 to 30. Crossing the 30-per-hour threshold signals severe sleep apnea, which carries greater health risks and usually requires more intensive management.