Excessive Daytime Sleepiness

Daytime sleepiness is excessive if it interferes with functioning and persists despite efforts to obtain adequate nocturnal sleep.

Geriatric Essentials

• Excessive daytime sleepiness is common among the elderly; it can noticeably impair cognition and functioning and predispose to automobile and other accidents.
• The cause should be identified; sleep apnea, which can lead to serious cardiopulmonary problems, must be excluded as the cause.
• Drugs are a common cause, and the resulting daytime sleepiness is often unrelated to the length or quality of nocturnal sleep.
• Hypothyroidism, which is common among the elderly, may cause daytime sleepiness.
• Because obstructive sleep apnea is a common cause of excessive daytime sleepiness, elderly patients with excessive daytime sleepiness of unknown cause should not be treated with sedative-hypnotics.

Occasional daytime sleepiness is normal. Many elderly people become tired during the day, especially if they have a disorder that causes nocturnal symptoms or if they take many mildly sedating drugs. Daytime sleepiness is especially common among people temporarily deprived of nocturnal sleep. However, if daytime sleepiness persists and interferes with functioning, it is abnormal.

Causes include chronically inadequate or poor-quality nocturnal sleep (which may result from chronic insomnia), sleep apnea (obstructive sleep apnea is a common cause in the elderly), periodic limb movement disorder, and sedating drugs. These drugs include antihistamines, some antihypertensives such as -blockers and clonidine, sedating antidepressants, antipsychotics, anticonvulsants, and some analgesics. Hypothyroidism causes excessive daytime sleepiness and significantly decreases stages 3 and 4 NREM sleep time.

Excessive daytime sleepiness may cause fatigue, lethargy, and impaired memory and concentration. The effects may be more noticeable in elderly patients, who may have less physical or cognitive reserve than younger patients. The degree of sleepiness can be quantified using a standard, validated scale such as the Epworth Sleepiness Scale (see Table 47-4).

Patients are evaluated for treatable causes. The patient's bed partner should be asked to describe the patient's snoring and breathing patterns and behaviors during sleep, which may suggest another sleep disorder (eg, obstructive sleep apnea, a parasomnia). A 30- to 60-min daytime nap helps some patients. Because obstructive sleep apnea is a common cause of excessive daytime sleepiness in the elderly and sedative-hypnotics are contraindicated in patients with obstructive sleep apnea, sedative-hypnotics should not be prescribed for elderly patients with excessive daytime sleepiness unless obstructive sleep apnea has been excluded.

This topic was last updated March 2006.