apnea-hypopnea index (AHI)

The apnea-hypopnea index (AHI) is a measurement used to assess the severity of sleep apnea. It counts the average number of breathing interruptions—called apneas (complete pauses) and hypopneas (partial reductions in breathing)—that occur per hour of sleep. A higher AHI indicates more frequent breathing disruptions, which can lead to poor sleep quality and health issues. Sleep specialists use this index to diagnose sleep apnea severity: - Mild: 5-15 events/hour - Moderate: 15-30 events/hour - Severe: over 30 events/hour