Sleepiness or Excessive Daytime Somnolence

Article Outline

• Abstract
• Background
• Sleep Terminology
• Sleep Architecture
• Sleep Stages
• Causes and Treatment of EDS
  • Insomnia
  • Restless Leg Syndrome (RLS)
  • Obstructive Sleep Apnea (OSA)
  • Assessment
• Sleep Hygiene Measures
• Pharmacologic Treatment
• Complementary and Alternative Medicine (CAM)
• Challenges in Assisted Living
• Acknowledgement
• Resources
• References
• Biography
• Copyright

Excessive daytime somnolence (EDS) is associated with age-related changes, environment, circadian rhythm or sleep pattern disorder, insomnia, medications, lifestyle factors, depression, pain, and illness. The notion of “sleep architecture” connotes a structure that describes the sleep cycle (i.e., stages) and wakefulness during a single sleep period—that is, rapid eye movement (REM) and non-REM sleep. Circadian rhythms perform a variety of functions including regulation of the quality and distribution of the stages of sleep. Insomnia includes delayed sleep onset as well as premature wakening; sleep is nonrestorative. Comorbidities associated with insomnia are Alzheimer's disease and other dementias, delirium, depression, congestive heart failure, chronic obstructive pulmonary disease, gastroesophageal reflux disease, pain, degenerative diseases of the neurological system, and sleep apnea. Continuous inadequate sleep affects cognitive function, physical performance, overall well-being, and quality of life. There is a greater risk of falls from insomnia than is the use of hypnotics to manage it. Sleep disruption among older adults is underrecognized and undertreated. Assessment using valid tools can be performed rapidly. There are a variety of treatment options, including sleep hygiene and pharmacological and alternative modalities.

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• Sandi Flores

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• Ethel Mitty

O sleep, O gentle sleep, Nature's soft nurse,

How have I frighted thee,

That thou no more wilt weight my eyelids down

And steep my senses in forgetfulness?

—Wm. Shakespeare, King Henry IV

We spend one third of our lives in sleep, and if we do not get enough of it, we are not only cranky, fatigued, and perhaps inattentive, but prone to error and mishap. Continuous inadequate sleep affects cognitive function, physical performance, overall well-being, and quality of life. Excessive daytime somnolence or “excessive sleepiness” is a common syndrome among older adults and is primarily associated with sleep deprivation. The 3 major causes of excessive daytime somnolence (EDS) are insomnia, restless leg syndrome (RLS), and obstructive sleep apnea (OSA). This article will describe “sleep architecture,” age-related changes in sleep and causes of EDS, sleep assessment, sleep hygiene care for the assisted living resident, and some treatment modalities, including complementary alternative medicine (CAM).

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Background 

EDS is associated with age-related changes, environment, circadian rhythm or sleep pattern disorder, insomnia, medications, lifestyle factors, psychological disorders, and medical illness. Yet many older adults as well as health care professionals regard “daytime sleepiness” as a normal companion of aging about which nothing can be done.¹ This misperception prevents appropriate evaluation and treatment—many of which are quite effective.

At least 20% of all adults in the United States have sleep problems; consider the robust over-the-counter (OTC) market for sleeping aids. Cardiovascular disease (e.g., myocardial infarction, congestive heart failure), particularly among older women, is associated with daytime sleepiness.¹, ² Insomnia occurs in more than 50% of adults aged 65 years or older and ranges from 45% to 75% in nursing homes.²

Older adults need as much sleep as younger adults, but sleep might be distributed between daytime naps and nighttime sleeping. Among 198 randomly selected assisted living residents, 69% reported sleep disturbance, 42% described symptoms of insomnia, and almost 37% described EDS.³ Residents were administered various tests to measure dementia severity and behaviors, depression, activities of daily living (ADLs) function, and general medical health (i.e., comorbidities). A sleep questionnaire (SQ), developed by the Johns Hopkins Alzheimer's Disease Research Center, was also administered. The SQ consists of 11 items arrayed on a 3-point Likert scale: 0 = no problem, 1 = mild-to-moderate problem, and 3 = chronic and severe problem; it addresses sleep maintenance, sleep apnea, EDS, napping, dream content, and so on. Interestingly, the prevalence of insomnia among AL residents is similar to that reported among nursing home residents—that is, 70%. The investigators, to their surprise, found that residents with insomnia did better on the Mini-Mental Status Exam (MMSE) and on physical performance than residents who did not report insomnia. The researchers note that one of the treatments for depression is sleep deprivation and that insomnia has been associated with decreased mortality. However, daytime sleepiness (and “daytime nappers”) have an increased mortality rate over 4 years and demonstrate less robust cognitive performance and functionality compared with those who do not exhibit daytime sleepiness.³ Hypnotics and nonsedating antidepressants were commonly used to treat insomnia.

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Sleep Terminology 

The terms defined in Table 1 can be useful in constructing a sleep profile even before specific measurements are taken and interviews conducted.

Table 1. Sleep Terminology

Data from references 4 and 5.

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Sleep Architecture 

“Sleep architecture” connotes a structure used to describe the sleep cycle (i.e., stages) and wakefulness during a single sleep period—that is, rapid eye movement (REM) and non-REM sleep (discussed later). Circadian rhythms (also known as biorhythms) perform a variety of functions: regulation of body temperature, metabolism, digestive processes, hormone secretion, and the quality and distribution of the stages of sleep. A circadian rhythm has an approximate daily periodicity but tends to be a bit longer than 24 hours and varies between individuals. (These rhythms are present in plants and animals as well.) It is independent of time cues per se but is dependent on light cues for the sleep-wake cycle, which is why the lights are turned down in submarines as well as in intensive care units to mimic and differentiate daytime from nighttime. Many people (normally) feel groggy when they wake up and want to go back to sleep, to “sleep out” until they no longer feel sleepy. This is not recommended because it throws off the circadian clock. Rather, consistent wakeup time helps the circadian rhythm remain “in synch” with the time of day.¹, ⁶, ⁷

Age-related changes in circadian rhythm are subtle and do not result in insomnia. However, older adults may become less responsive to changes in the light of day. As such, they may feel sleepy in the early evening and go to sleep only to wake up around 3 or 4 a.m. and then be unable to go back to sleep. Another older adult with advanced sleep-phase syndrome (ASPS) might catnap in the early evening and then be unable to fall asleep or remain asleep when they go to bed. This speaks to the importance of accurately describing and documenting the wake and sleep patterns of older adults who describe being unable to sleep or are wakeful at night.¹ Overall, older adults have decreased total sleep time and “sleep efficiency.”

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Sleep Stages 

REM differentiates between the 2 stages of sleep: REM and non-REM (NREM). Research indicates that NREM is associated with the integrity and health of the immune and digestive systems. It consists of 4 stages:

REM sleep, also known as “dream sleep” or “S-state sleep,” is only a few minutes long at first, and then lengthens as sleeping continues. It is necessary for emotional well-being and memory retention and accounts for almost 20% of total sleep. Studies have demonstrated that interrupting or denying REM sleep over a prolonged time can cause aberrant behavior, including psychosis. REM sleep is characterized by rapid eye movement (hence, its name), increased heart rate, and irregular respirations. The musculature of the upper airway relaxes; the brain consumes more oxygen, and body temperature regulation disappears. Vivid, active, complex dreams occur in this stage, as can penile erection. REM has 2 phases, both of which are present in every stage:

Sleep cycles last 90–110 minutes and typically consist of 1 NREM and 1 REM stage. The relationship of body temperature, delta sleep, “sleep debt” (i.e., prior wakefulness) and what researchers call a “circadian oscillator” is beyond the scope of this article. However, most sleep researchers feel that REM sleep occurs during the last third of total sleep because of these interacting factors.⁷

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Causes and Treatment of EDS 

Insomnia 

The definition of insomnia includes delayed sleep onset as well as premature wakening or getting up so early that sleep is nonrestorative.¹ Causes can be medical, functional, emotional, neurological, pharmacological, environmental, and psychosocial. Comorbidities in elder adults associated with insomnia are Alzheimer's disease and other dementias, delirium, depression, congestive heart failure (CHF), chronic obstructive pulmonary disease (COPD), gastroesophageal reflux disease (GERD), pain, degenerative diseases of the neurological system, and sleep apnea.² A cautionary note: an older adult with insomnia who appears confused as a result of sleep deprivation might be misdiagnosed as demented.

Insomnia is associated with a greater risk of falls than is the use of hypnotics to manage the condition.¹, ² This finding contradicted previously held beliefs about the use of hypnotics and the likelihood of falls. Comfort with this conclusion (and prediction) is grounded on the observation that insomnia is associated with impaired motor performance, EDS, and ambulation at night. Nevertheless, the debate with regard to use of hypnotics for insomnia continues. At present, a short-acting hypnotic in combination with treatment(s) for the likely causes of insomnia (e.g., pain, depression) together with sleep hygiene measures is recommended. The American Academy of Sleep Medicine and the American Psychological Association have identified and endorsed effective insomnia treatment measures that would be instituted by a sleep therapist or other appropriate clinician. Cognitive-behavioral therapies have demonstrated effectiveness, but their applicability and outcome with regard to older adults has not been reported.

Restless Leg Syndrome (RLS) 

This condition can interfere with getting to sleep and remaining sleep. It affects people of all ages, from children to older adults. Characteristically, RLS is described as a not-to-be-ignored urge to move the lower extremity (1 or both) in response to a “disagreeable sensation” in the limb.¹ Rarely felt while moving about, RLS appears during periods of inactivity. Movement of the leg is purposeful in response to a “creepy crawly” sensation that is relieved by movement. It can be a side effect of some medications (e.g., tricyclic antidepressants, lithium, dopamine blockers) but also caused by certain conditions: anemia, uremia, diabetes mellitus, Parkinson's disease, rheumatoid arthritis.¹ A similar condition, nocturnal myoclonus, (originally known as periodic limb movement disorder) presents as involuntary flexion of the leg and foot the leg “jumps around.” It can but does not always disrupt sleep. The most effective medication is a dopaminergic drug (i.e., dopamine agonist). Sinemet was used at first, but it is not recommended at present because of augmentation of symptoms. Pramipexole (Mirapex) and ropinoso (Requip) are currently the drugs of choice; there is less risk overall and less likely increase in symptoms. Effectiveness of other medications, such as opioids, iron, benzodiazepines, and anticonvulsants for RLS treatment has not been established for older adults.¹

Obstructive Sleep Apnea (OSA) 

This condition is associated with aging, particularly among older adults who are overweight or obese. Normal age-related changes, such as diminished lung capacity and muscular endurance and alteration in sleep architecture are predisposing factors. OSA is defined as intermittent pharyngeal obstruction that prevents air flow for at least 10 seconds.¹ Sleep interruption is usually preceded by snoring and gasping after which airflow in the upper airway is restored. The diagnosis of OSA is made if these events happen more than 5 times in a single hour of sleep and are accompanied by snoring, gasping, and daytime sleepiness.¹ Sufferers also report daytime sleepiness and impaired mental and physical functioning, likely because of insufficient REM sleep time and fragmented sleep.

The gold standard treatment is continuous positive airway pressure (CPAP). Air is blown through a mask into the nose to prevent airway collapse. Variations on CPAP are bilevel positive airway pressure and what is known in the trade as “smart” airway pressure devices. The bilevel mechanism senses if the individual is breathing in and out and varies the pressure level: greater pressure on inspiration to prevent apnea; less pressure or resistance on expiration. The smart devices use sensors to detect flow and pressure being generated in the airway in combination with automatic regulation paradigms.⁸ Other treatments can be surgical intervention (e.g., palatoplasty), oral appliances, and weight loss (if applicable).

Assessment 

The preadmission or admission assessment is a perfect opportunity to obtain a sleep history and assess for EDS. A few simple questions can be asked, after which a more in-depth assessment can be performed to identify and rule out cause(s) of significant sleep disturbance. Following are useful questions to include in the assessment.

A sleep log can be instituted, across all shifts, for 5–7 days. The log describes sleep and awake time in minutes or hours and when each was occurring. The information (data) should be recorded by the staff, not by the resident. The resident's activities during the wake time should be described. Rather than characterizing the activity as “agitation” or “confusion,” it should be described in behavioral terms: walking about, unable to find dining room or own room (even after given directions), persistently asking questions, and so on. Any specific intervention provided during the wake time (and their effect) should also be recorded: analgesic medication, repositioning, food or fluid(s) offered and taken, ambulation assistance on the unit, and so on. The sleep log should also be instituted after initiation of a sleep medication or other kind of intervention to assess effectiveness.

There are several technological sleep pattern assessment methods, some of which are obtrusive and counterproductive for an older adult.² Polysomnography is the gold standard assessment to record sleep stages, but it is expensive and usually done in a sleep lab. An older adult with significant anxiety or moderate to severe dementia is unlikely to cooperate with this kind of examination. Pulse oximetry is noninvasive, not very expensive, and not obtrusive, but for diagnosis of OSA, it must be conducted at night and on a schedule that probably has to be worked out over several nights.

The Epworth Sleepiness Scale (ESS) is one of the most valid and reliable instruments used to assess the severity of EDS and whether further assessment and intervention is necessary. It is easy to administer and score and is available on the Internet.¹, ⁹ Using a Likert-type scale, the respondent indicates whether they would never doze (0), had a slight chance of dozing (1), had a moderate chance of dozing (2), or had a high chance of dozing (3) with regard to 8 very simply stated situations, such as sitting and reading, in a car while stopped in traffic, sitting inactively at a meeting or in the theater, and so on. The numerical results range from getting enough sleep to being dangerously sleepy. Given that this is a subjective report of sleepiness or if the respondent is not sufficiently English-language literate, the results could be inaccurate. However, the items are phrased such that they are not threatening or accusatory.

The Pittsburg Sleep Quality Index (PSQI) measures 7 areas of sleep, including sleep quality, duration, and disturbances. It solicits information regarding medications used for sleep and for inability to function in the daytime over the preceding 30 days.¹⁰ Respondents must address questions about usual bedtime, length of time to fall asleep, usual arising time, and the hours spent actually sleeping (that might be other than the hours spent in bed). Likert-type questions address the frequency in the past month that the individual was unable to get to sleep in 30 minutes, woke in the middle of the night, felt too cold or too hot, had bad dreams, was in pain, and so on. As with the ESS, the PSQI has risks associated with language literacy and is also a subjective report. Nevertheless, both assessments/scales can be used for comparative measurements with older adults in a variety of settings, including community-based living, and to track the efficacy of specific interventions.

A questionnaire for sleep apnea risk, consisting of 5 questions, includes the ESS score, frequency of being told that one's snoring is disturbing others' sleep or that one has stopped breathing during sleep, being overweight, and medical history (including hypertension, heart disease, excessive fatigue, difficulty concentrating, or remaining awake during the day).¹¹ Responding that these events happen 1–3 times each week to all the questionnaire items indicates sleep apnea risk and a recommendation to consult with a primary health care provider (physician, nurse practitioner).

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Sleep Hygiene Measures 

In collaboration with the resident, sleep hygiene measures not only can restore effective sleep but can (re)establish health promoting/maintaining lifestyle practices.¹, ⁷ The assisted living nurse is counselor and clinician for the older adult in advising and monitoring appropriate sleep (and lifestyle) measures. Several cognitive-behavioral theories can frame the approach taken with the resident: self-efficacy theory, motivation theory, the health belief model. Although sleep hygiene measures are commendable, they need affirmation and motivation drawn from the older adult's experience with past challenges and stressors, coping methods, understanding of the approach, desire to restore restful sleep, and willingness to try. Sleep hygiene is somewhat like a multidisciplinary approach; it is certainly resident-centered. Aspects of sleep hygiene for an assisted living resident include the following:

How long should a planned nap be? Less than 30 minutes up to 1 hour is the maximum. The data are inconclusive, and the issue is hotly debated. In general, if the nap does not preclude falling asleep at night, then it is likely beneficial. “Bright-light therapy” is an attempt to reestablish the biological sleep clock, or circadian rhythm. The data are slim with regard to the effectiveness of different kinds of lamps, number of lumens (watts), and length of exposure. There does not appear to be any harmful effect, however, from 30–60 minutes exposure daily. It bears noting that excessive daytime napping could be a sign of boredom, social withdrawal, and depression and needs to be evaluated.

Bright-light therapy is used for circadian rhythm disturbances, especially for what is known as delayed phase sleep disorder (DPSD). The treatment consists of timed exposure to bright light; the amount of time is based on controlled trial-and-error of timed exposure and sleep results. This modality is also used to treat depression and for Seasonal Affective Disorder or SAD.

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Pharmacologic Treatment 

As noted earlier, there is a greater risk of falls from untreated insomnia than from appropriate use of hypnotic medications. Dietary supplements and herbals (e.g., melatonin, valerian) are ineffective for treatment of insomnia, as far as the empiric data indicates.² Pharmacologic treatment seeks to remove or treat the causes of EDS, particularly with regard to the progression of insomnia from an acute or transient status to chronic status. The medication selected varies with the goal of treatment; that is, to reduce arousal, prepare the patient for cognitive-behavioral therapy, or break the cycle of chronic insomnia. The best medication is prescribed by knowing the individual: cognitive abilities, presence of depression, alcohol use, other medications (including OTC), and comorbidities.

Side effects of sleep medications, typically hypnotics, are agitation, ambulation disturbance, headache, sleepiness, disorientation, impaired functionality, risk of falls, mood changes, upsetting dreams, and oversedation, among others.² “Rebound sleepiness” can occur with treatment of insomnia as a result of sleep deprivation; it goes away with time. An ideal sedative-hypnotic would have the properties listed in the following list, but it is unlikely that the medication would simultaneously and effectively treat the underlying cause of the insomnia. The medication should:

Antihistamines are not Food and Drug Administration approved for insomnia management; however, diphenhydramine and doxylamine are prescribed for older adults even though they are not effective in the long term. The anticholinergic properties of antihistamines can cause delirium, confusion, and urinary retention.² It is recommended that sedative antidepressants should be used to treat insomnia only if in the presence of depression. Benzodiazepine receptor agonists (BzRAs) are sedative-hypnotics with significant risks for central nervous system side effects such as amnesia, ataxia, and sedation. Space does not permit a full review of the pharmacological agents reported to effectively treat insomnia. There is a paucity of data with regard to their effectiveness in older adults.

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Complementary and Alternative Medicine (CAM) 

Slightly more than 40% of Americans use some type of CAM, but almost 90% of older adults do so, many of whom do not tell their primary care provider (i.e., physician, nurse practitioner). Defined as the use of products and practices that are not part of Western (allopathic) medicine, CAM is purportedly used for many chronic illnesses and conditions, many of which can cause sleep disturbances: cardiac disease, diabetes mellitus, arthritis, and back pain.⁴ The CAMs of choice for these conditions includes herbal medicines, relaxation techniques, megavitamin therapy, chiropracty, and spiritual or religious ministrations. Herbals such as ginkgo biloba and ginseng are used to improve cognitive function, often in combination with megavitamins, massage, and biofeedback.⁴

Acupuncture, a staple of Chinese medicine, is effective in treatment of insomnia by virtue of its mechanism that moderates stress. Research indicates that dopamine, a neurotransmitter associated with sleep regulation, is released pursuant to the effect of acupuncture on brain circulation.⁴ Pain is reduced with acupuncture because it stimulates release of the body's opioids; thus, sleep disturbance can be reduced. A well-controlled study reported that auricular acupuncture in combination with magnetic pearls improved sleep efficiency and total sleep time over several months' duration.⁴

Music therapy and aroma therapy, particularly lavender, have both demonstrated measurable improvement in sleep quality and duration. There is little objective and robust scientific research that supports the use of herbals to treat sleep disorders. Tai chi in combination with meditation can improve sleep quality and reduce daytime sleepiness.⁴ To date, studies with regard to effectiveness of magnet therapy on sleep disturbances is inconclusive.

The hormone melatonin affects biorhythm and has been used for jet lag. A synthetic version is being tested for insomnia treatment.⁴ Theanine, a component of green tea, peppermint tea, and St. John's wort purportedly improve sleep quality, in part by reducing anxiety.⁴ Given the panoply of CAM options, objective measures of their effectiveness and safety for use with older adults requires further study.

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Challenges in Assisted Living 

The philosophy of assisted living is that of resident autonomy/self-determination and choice: residents are encouraged to set their own routine. In general, evening or night staffing in assisted living residences (ALRs) is less than 50% of daytime staffing. Residents who choose to retire at “unusual” times of day pose challenges to the regulatory requirements that ALRs monitor and supervise the residents. Most ALRs do not offer planned or social activities after 8 p.m.

Resident and family education regarding falls risk and the indiscriminate use of sleep aids/medications (including CAM) is clearly necessary, and assisted living nurses must have the education and skills to provide this. (See the Resources section of this article, which includes useful information for nurses, as well as for residents and families.) Residents (or their families) are not prohibited from purchasing OTC sleep aids. To manage this, many AL residences have a policy that prohibits the use of OTCs (including herbals) without staff knowledge. In some residences, OTCs cannot be stored in the resident's room.

Residents with dementia tend not to maintain regular sleep patterns. Having an activity person in the evening to engage residents provides support not only to the residents but also to the (fewer) staff members at that time of day, who are constantly alert to redirect residents to someplace other than bed. Industry standards may require 2-hour night checks, particularly for residents with dementia, which can be annoying and imposing on many residents, their quality of sleep, and their privacy. Some assisted living providers have sought recourse by using a form that essentially states a resident “refuses night checks.” The document spells out the essential risks of refusal. The accountability that this places on nursing is unknown and untested in the courts.

Technology can assist—and ameliorate—the impositions of sleep monitoring. Devices range from monitoring sleep patterns (that might be useful for OSA) to simple bed alarms. Virtually all states prohibit the use of cameras in resident rooms, except in very unusual circumstances. But can music be piped in?

Given all the likely causes of EDS, it might be most cost-effective to begin with the actual environment, especially at night: the noise level. For urban dwellers, there is nothing quite like the sound of the garbage truck rumbling down the street at 3 in the morning—reassuring to some, surely. But to the person already awake or “rudely” awakened, hardly so; it tells them what time it is. Ask residents what sounds they were accustomed to at night in their previous environment; what sounds jar them awake and keep them so? What about airplane noise? Fire and police sirens? Is their sleep pattern better in the winter when the windows are closed and worse in the summer with open windows? Ask them what “tricks” they used to lull themselves to sleep in the past, and what might be appealing to them now. Some examples include naming the states in alphabetical order, naming 3 cities in alphabetical order, or 3 flowers, or 3 countries. What happened to the sheep? What job or activities made life pleasant for the resident before coming to the ALR, and how can they be rolled into a “sleep mantra”?

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Acknowledgement 

The authors wish to thank Dr. Carolyn Auerhahn, EdD, APRN, FAANP, Clinical Associate Professor and Coordinator, Geriatric and Adult/Geriatric Nurse Practitioner Programs, College of Nursing, New York University for her thoughtful reading of this article.

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Resources 

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References 

1. Chasens ER, Williams LL. Umlauf MG. Excessive sleepiness. In:  Capezuti E,  Zwicker D,  Mezey M editor. Evidence-based geriatric nursing protocols for best practice. 3rd ed. New York: Springer: Publishing Company; 2008;p. 459–476
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