Which condition could lead to the need for polysomnography?

The correct answer is the condition associated with consistent low SpO2 levels, as this suggests a potential issue with oxygenation during sleep. Polysomnography, commonly known as a sleep study, is performed to monitor various physiological parameters while a patient sleeps. This includes brain activity, eye movements, heart rate, and oxygen levels in the blood.

When a patient exhibits consistently low levels of oxygen saturation, it may indicate sleep apnea or another sleep-related respiratory disorder. Conditions such as sleep apnea can lead to significant drops in oxygen saturation during sleep, and polysomnography is a critical diagnostic tool to identify and evaluate such disorders. This helps in determining the need for interventions like continuous positive airway pressure (CPAP) therapy or other treatments.

Other conditions mentioned, such as unexplained headaches, shortness of breath during exercise, and a persistent cough, may require different diagnostic approaches and do not necessarily relate directly to sleep disturbances or the need for a sleep study. While they can be serious, they are not specifically indicative of sleep-related issues requiring polysomnography.