Breathing-Related Sleep Disorder

Breathing-related sleep disorder is characterized by a clinical complaint of excessive daytime sleepiness or insomnia or both. These symptoms result from periodic cessation of breathing (apnea), diminished amplitude of airflow (hypopnea), or increased work of breathing (upper airway resistance syndrome). These findings can be confirmed only during polysomnographic studies, although clinical history from the patient or bed partner may include breathing pauses or gasps. Other typical clinical symptoms include loud snoring and daytime sleepiness characterized by long, unrefreshing naps, as well as shorter episodes of inadvertent sleep.

Obstructive sleep apnea syndrome typically occurs in overweight, middle-aged men, who frequently have evidence of hypertension or cardiovascular disease. Reduced muscle tone during sleep and reduced airway patency due to obesity or craniofacial abnormalities lead to a collapse of the airway during inspiration. The cessation of breathing and resulting decreases in oxyhemoglobin saturation lead to arousal. This pattern may recur hundreds of times per night. Central sleep apnea syndrome, in which apneas occur with diminished central drive for respiration, occurs more commonly in individuals with congestive heart failure or central nervous system disorders, such as cerebrovascular disease. Although it clearly represents a physical condition, breathing-related sleep disorder is included as an Axis I condition in DSM-IV to facilitate the differential diagnosis of hypersomnia.

Behavioral/psychotherapeutic treatment Behavioral interventions for sleep apnea involve general avoidance measures, sleep position training, and weight loss. Most central nervous system depressant drugs aggravate sleep-related breathing disorders and increase oxyhemoglobin desaturation. Patients with sleep apnea should avoid sedative-hypnotics and alcohol 4-6 hours before bedtime (Guilleminault et al. 1984; Scrima et al. 1982).

Snoring and respiratory disturbances are typically worst when the patient sleeps in the supine position. Some patients, usually those of normal weight, may have sleep apnea that is strictly positional in nature. Interventions aimed at changing sleep posture should benefit these patients. A common home remedy is to sew a tennis ball into the back of a pajama to discourage the patient from sleeping on the back. Training to avoid the supine position can also be achieved with a gravity-sensitive position device that triggers an alarm whenever the patient is in the supine position. In one study, 10 patients with positional sleep apnea reduced their sleep apnea by about half after a single night of sleep position training, and 6 patients completely eliminated their apnea (Cartwright et al. 1985). A similar conditioning procedure was used to train patients with sleep apnea to resume breathing whenever there was a cessation of airflow for more than 5 seconds or a decrease in oxygen saturation below 90% (Badia et al. 1988). This procedure yielded a modest reduction in the duration, but not the frequency, of apneic events and a corresponding improvement in oxyhemoglobin saturation.