Do You Ever Take a Sleep History?

Obstructive sleep apnea is a condition in which the pharynx repeatedly collapses during sleep. The patient with obstructive sleep apnea struggles to breathe against a closed airway, resulting in hypoxemia and hypercapnia. Eventually the patient awakes from sleep, the pharyngeal muscles contract, the airway opens, and air rushes in under pressure, creating a loud snorting or gasping sound; in general, this process is subconscious. The patient then drifts into deeper sleep, and the cycle repeats itself. The combination of sleep fragmentation and arterial blood gas alterations can lead to excessive daytime sleepiness, problems with memory, problems with attention and concentration, and personality changes. Blood pressure typically increases in association with apneas during the night, and there is a strong interaction between daytime hypertension and obstructive sleep apnea.

The true prevalence of obstructive sleep apnea is unknown, in part because of disagreement about its definition. An obstructive apnea is an event during which the throat closes off for 10 seconds or more and there is no air flow. An obstructive hypopnea is typically an event involving a decrease in air flow associated with either electroencephalographic arousal from sleep or oxygen desaturation. Using the definition of an apnea-hypopnea index of 5 episodes or more of apnea-hypopnea per hour of sleep in association with daytime sleepiness, Young and colleagues (1) found …