The Apnea-Hypopnea Index is a parameter derived from sleep study data, specifically polysomnography or home sleep apnea testing. It quantifies the severity of sleep apnea by measuring the average number of apneas and hypopneas per hour of sleep. It is a key metric used in diagnosing and categorizing the severity of sleep-disordered breathing.

The Apnea-Hypopnea Index (AHI) is a measure used in sleep studies to quantify the severity of sleep-disordered breathing, particularly in conditions such as obstructive sleep apnea (OSA). In sleep studies, data such as airflow, respiratory effort, oxygen saturation, and sleep stages are recorded over the course of a night's sleep. These data are often displayed graphically in polysomnography (PSG) reports or other sleep study reports. The AHI is derived from the number of apneas (complete cessation of airflow) and hypopneas (partial reduction in airflow) observed during these recordings, typically expressed as the average number of events per hour of sleep. Graphs or charts in sleep study reports may show trends in airflow, oxygen levels, and other parameters over time, which can indirectly reflect the severity of sleep-disordered breathing and the AHI. Additionally, treatment efficacy and changes in AHI may be visualized before and after interventions such as continuous positive airway pressure (CPAP) therapy. While the AHI itself may not be directly represented by a picture, visualizations of sleep study data can provide valuable insights into sleep-disordered breathing patterns and treatment outcomes.