Geriatric Sleep Disorder 

Sleep disorders are commonly underdiagnosed and a significant source of concern in the geriatric population.^[1] Several diverse factors may contribute to sleep disturbances in a large proportion of the elderly. These contributing factors include changes associated with aging, such as retirement, health problems, death of spouse/family members, as well as changes in circadian rythym.^[2] Changes in sleep patterns may be part of the normal aging process; however, many of these disturbances may be related to pathological processes that are not considered a normal part of aging.^{[3, 4]}

In addition to affecting quality of life (including excessive daytime sedation, physical, psychological, cognitive problems affecting overall health of the patient^[4] ), sleep disorders have been implicated with an increased mortality rate. Unfortunately, the number of medications increases with age, which in itself can lead to more morbidity, mortality, side effects such as falls^[5] , cognitive impairment, financial stressors, and even sleep disturbances.^[6] Treating insomnia in the elderly can improve the overall health of the patient, but care must be taken when medications are used in this particular population.^[1]

Treatments for sleep disorders include over-the-counter and prescription medications, behavioral treatments, relaxation techniques, sleep hygiene, sleep restriction, light therapy^[7] , cognitive behavioral therapies^{[3, 8]} , valerian, Tai Chi, yoga, meditation, acupuncture, and acupressure^[9] .

See Medscape's Insomnia and Sleep Health Resource Center.

Normal sleep is organized into different stages that cycle throughout the night. Polysomnographic studies have classified the sleep stages into the following categories:

• Rapid eye movement sleep

  • Rapid eye movement (REM) sleep (ie, paradoxical desynchronized sleep) is the stage of sleep during which muscle tone decreases markedly; this stage is associated with bursts of conjugate gaze and dreaming.
  • Relative amounts of REM sleep are maintained until extreme old age, when they show some decline.
• Non-REM sleep

  • Non-REM sleep is subdivided into 4 stages. Stages 1 and 2 constitute light sleep; stages 3 and 4 are called deep sleep or slow-wave sleep (SWS).
  • With aging, an increase in the duration of stage 1 sleep and an increase in the number of shifts into stage 1 sleep occur.
  • Stages 3 and 4 decrease markedly with age, and, in extreme old age (>90 y), stages 3 and 4 may disappear completely. Some studies, however, have found that elderly women tend to have normal or even increased stage 3 sleep, whereas men have normal or reduced stage 3 sleep.

The following definitions are provided:

• Time in bed: Older individuals spend more time lying in bed at night without attempting to sleep or unsuccessfully trying to sleep. They also use the bed for resting and napping during the day.
• Total sleep period: This refers to the time from sleep onset to the final awakening from the main sleep period of the day. Total sleep period increases with age because of the increase in the number of awakenings.
• Total sleep time: This refers to the total sleep period minus the time spent awake during the sleep period. Studies have found the total sleep time to be either reduced or unchanged in the older population compared with younger age groups.
• Sleep latency: This is the time from the decision to sleep to the onset of sleep. Studies have found considerable variability in individuals. In females, sleep latency has been related to age increase in adults and hypnotic drug use, which would decrease sleep latency.
• Wake after sleep onset: This is the time spent awake from sleep onset to final awakening. An increase occurs in the time spent awake after sleep onset in the older population. Webb was able to attribute 38% of nocturnal arousals in a study to physical discomfort (eg, bladder distention, urinary urgency). Pain, restless legs, and dyspnea have also been identified as factors in arousal during sleep.
• Sleep efficiency: This is the ratio of total sleep time to nocturnal time in bed. Most studies have found sleep efficiency to be decreased in the older population.
• Nocturnal penile tumescence (NPT): Studies show that a gradual decline in NPT during REM sleep occurs with age, even though the duration of REM sleep remains fairly constant until extreme old age.
• Other changes: Few data describe cardiovascular changes during sleep in the older population. Zepelin found that auditory awakening thresholds from stage 4 sleep were significantly lower during the first night's sleep in a sleep laboratory in older men than in younger men.^[10]

Older people spend more time in bed to get the same amount of sleep they obtained when they were younger; however, the total sleep time, at most, is only slightly decreased, with an increase in nocturnal awakenings and daytime napping. They often report having earlier bedtimes and an increased sleep latency (time to fall asleep), but excessive daytime somnolence is not part of normal aging. Older subjects have been observed to be more easily aroused from sleep by auditory stimuli, suggesting increased sensitivity to environmental stimuli.

Frequency

United States

Sleep disturbance or insomnia is the third most common patient complaint, ranking behind headaches and the common cold. Approximately 15% of the adult population in the United States has insomnia of significant enough severity to seek medical attention. More than 50% of elderly people have insomnia.^[11] Of the US population, 1.7% receive a hypnotic prescription annually, and another 0.8% purchase nonprescription sleep aids. Fifty million Americans occasionally take some form of sleep medication.

Mortality/Morbidity

In addition to affecting the quality of life, sleep disorders have been implicated with excess mortality. Two primary sleep disorders that increase with age are sleep apnea (SA) and periodic limb movements in sleep (PLMS). Sleep apnea can result in daytime hypersomnolence, systemic hypertension, cardiac arrhythmias, cor pulmonale, and sudden death. Among a random sample of 427 older volunteers, 45% had PLMS, and they each reported dissatisfaction with sleep, sleeping alone, and kicking at night. Yaffe et al suggest older women with sleep-disordered breathing (characterized by recurrent arousals from sleep and intermittent hypoxemia) have an increased risk of developing cognitive impairment compared with those without sleep-disordered breathing.^[12]

In a study of sleep-disordered breathing (SDB) and nocturnal cardiac arrhythmias in older men, Mehra et al found that the likelihood of atrial fibrillation or complex ventricular ectopy (CVE) increased along with the severity of sleep-disordered breathing. In addition, different forms of sleep-disordered breathing were associated with the different types of arrhythmias.

Polysomnography in 2,911 participants showed that the odds of atrial fibrillation (P=0.01) and of complex ventricular ectopy (P < .001) increased with increasing quartiles of the respiratory disturbance index (a major index including all apneas and hypopneas). Central sleep apnea was more strongly associated with atrial fibrillation (odds ratio [OR], 2.69; 95% CI, 1.61-4.47) than with complex ventricular ectopy (OR, 1.27; 95% CI, 0.97-1.66). In contrast, obstructive sleep apnea and hypoxia was associated with complex ventricular ectopy; participants in the highest hypoxia category had an increased odds of CVE (OR, 1.62; 95% CI, 1.23-2.14) compared with the lowest quartile. The results suggest that different sleep-related stresses may contribute to atrial and ventricular arrhythmogenesis in older men.^[13]

Sex

Older women are more likely to experience insomnia than older men. In a large epidemiological study of people older than 70 years, 35% of women reported moderate-to-severe insomnia, compared to only 13% of men.^[14]

Age

More than one half of people older than 64 years who live at home and two thirds of people older than 64 years who reside in a long-term care facility are estimated to have some form of sleep disturbance.