Which condition is typically diagnosed using polysomnography?

Polysomnography is commonly used to diagnose sleep disorders, making it a key diagnostic tool for chronic insomnia. This condition is characterized by difficulties in sleeping, including problems with falling asleep, staying asleep, or waking up too early and not being able to return to sleep. Polysomnography records various physiological data during sleep, such as brain wave activity, oxygen levels, heart rate, and breathing patterns, providing comprehensive insights into the sleep cycle and identifying any abnormalities that may contribute to insomnia.

Conditions like depression, COPD, and diabetes do not primarily rely on polysomnography for diagnosis. While sleep disturbances can occur in individuals with depression or other health issues, they are typically assessed through clinical interviews and questionnaires rather than through sleep studies. COPD is primarily evaluated using pulmonary function tests, and diabetes diagnosis is based on blood glucose levels and other metabolic indicators. Thus, polysomnography is most relevant for diagnosing chronic insomnia among the options provided.