Sleep

One of the most common sleep disorders is sleep apnea—the cessation of breathing during sleep for periods from seconds to minutes. Apnea may result from a loss of respiratory effort (central sleep apnea) or, more commonly, by an upper airway obstruction (obstructive sleep apnea), usually accompanied by loud snoring. An apneic episode usually ends with arousal to wakefulness and a gasping intake of breath. The resulting sleep disruptions lead to poor sleep and excessive daytime sleepiness (EDS). The incidence of apnea increases with age in both sexes, but it is more common in men, especially if they are overweight. Among people over age sixty-five, 24 percent have sleep apnea.

Sleep apnea and snoring have been implicated as secondary causes of morbidity and mortality in patients with cardiac and cerebrovascular disease, probably because of increased hypertension, lowered brain oxygen levels, and irregular heartbeats. EDS secondary to sleep apnea may be a serious and important risk factor for motor vehicle and other accidents. Use of sedative or hypnotic agents in undiagnosed apnea patients may exacerbate breathing problems and may even be fatal. Treatments for sleep apnea include continuous positive airway pressure (CPAP) to open up collapsed airways, weight loss, reduction of alcohol and sedative use, surgery, and dental devices.

Behavioral disorders associated with sleep are common, but increase further with age. A major concern is that these disorders disrupt sleep and lead to EDS, as well as decrements in daytime performance, social interactions, and physical and psychological health. Restless legs syndrome (RLS), is a disorder marked by a restless, ‘‘crawling’’ sensation in the legs that creates an irresistible urge to move them. Walking, massage, leg movements, or cold-water immersion may temporarily relieve the symptoms, but these are incompatible with sleep. Most RLS patients also have periodic limb movement (PLM) disorder, though this disorder can also occur independently. While PLM disorder is rare in those under thirty years of age, it occurs in approximately 45 percent of those over age sixty-five. PLM disorder involves repetitive movements of the feet and legs in bouts lasting several minutes. These occur frequently in stage 2 and often disrupt sleep. PLMs have been observed in patients with medical conditions such as uremia or diabetes, in patients with sleep apnea and narcolepsy, and in relation to the use or withdrawal of some drugs.

REM-sleep behavior disorder involves agitated movements during sleep in response to vivid dreams, resulting from a lack of the normal inhibition of muscle tone during REM. Trigger dreams often include themes of fleeing or fighting, resulting in the sleeper showing vigorous punching, kicking, and other movements, which may lead to injury to the sleeper or bed partner. While this condition is relatively rare, it increases in prevalence in males over age sixty. Pharmacological treatments may reduce but not eliminate these behavioral disorders of sleep.

Insomnia, or insufficient sleep, is characterized by self-reports of unsatisfactory sleep, daytime fatigue, and social or work impairment. Many factors (medical, psychological, environmental) contribute to insomnia, and it takes several different forms. Women complain more often of insomnia than men, especially during and after menopause. While younger adults typically show initial insomnia (difficulty falling asleep), older people tend to have difficulty with early awakening and sleep maintenance during the night. Among adults over sixty-five, 29 percent complain of problems maintaining sleep.