The Extraordinary Importance of Sleep

The Extraordinary Importance of Sleep
The Detrimental Effects of Inadequate Sleep on Health
and Public Safety Drive an Explosion of Sleep Research
Susan L. Worley
In the inaugural issue of the Journal of Clinical Sleep Medicine
(2005), a feature article1
traced early milestones in the developing field of sleep medicine, which slowly emerged from
the older field of sleep research during the 1970s and 1980s.
Sleep medicine, the article noted, was closely linked with and
made possible by the discovery of electrical
activity in the brain. The examination of electroencephalogram (EEG) patterns that occur
during sleep led to the classification of stages
of sleep, which in turn created an important
foundation for probing human sleep, discerning abnormalities, and discovering significant
relationships between sleep and health. By
2005, scientists and clinicians had not only
identified and clearly defined a large number of
sleep disorders but had discovered that many
of them were highly prevalent.
The pace of research and discovery has only
accelerated since 2005, and the number of peer-reviewed sleep journals has more than tripled.
Today, researchers are more deeply probing the cellular and
subcellular effects of disrupted sleep, as well as the effects of
sleep deprivation on metabolism, hormone regulation, and
gene expression. Newer studies are strengthening known
and suspected relationships between inadequate sleep and a
wide range of disorders, including hypertension,2
obesity and
type- 2 diabetes,3
impaired immune functioning,4
disease and arrhythmias,5,6 mood disorders,7
neurodegeneration and dementia, 8,9 and even loneliness.10
Research findings continue to underscore early concerns
about public safety that was first raised when major industrial
disasters such as the Exxon Valdez oil spill were linked to inadequate sleep.11 Related research sponsored by major organizations, including the U.S. Department of Transportation, the U.S.
Department of Defense, the National Institutes of Health, and
the National Aeronautics and Space Administration (NASA), has
helped to inspire national initiatives aimed at improving public
safety and health. However, despite the astounding acceleration in research during the past few decades, inadequate sleep
due to sleep disorders, work schedules, and chaotic lifestyles
continues to threaten both health and safety.
“Pushing against the wave of accelerated growth in the
the field has been a shoreline of indifference,” says David F.
Dinges, Ph.D., Professor and Chief of the Division of Sleep
and Chronobiology in the Department of Psychiatry at the
University of Pennsylvania Perelman School of Medicine.
“Modern industrial pressures to use time 24 hours a day have
led to shiftwork and a world in which virtually everything––law
Susan L. Worley is a freelance medical writer who resides in Pennsylvania.
enforcement, airports and all kinds of transportation, industrial
operations, and hospitals—operates 24/7. People have come to
value time so much that sleep is often regarded as an annoying
interference, a wasteful state that you enter into when you do
not have enough willpower to work harder and longer.”
It has become increasingly clear, however,
that no matter how hectic our lives may be, we
can no longer afford to ignore what research
is telling us about the importance of sleep for
our safety and mental and physical well-being.
Impact on Attention, Cognition, and Mood
While scientists are still working to identify and clarify all of the functions of sleep,12
decades of studies—many of which have used
the method of disrupting sleep and examining
the consequences—have confirmed that sleep
is necessary for our healthy functioning and
even survival.
“We know for sure that sleep serves multiple functions,” says Dr. Dinges. “Nature tends to be very
parsimonious in that it often uses a single system or biology
in multiple ways to optimize the functioning of an organism.
We know, for example, that sleep is critical for waking cognition––that is, for the ability to think clearly, to be vigilant and
alert, and sustain attention. We also know that memories are
consolidated during sleep, and that sleep serves a key role in
emotional regulation.”
Studies conducted by Dr. Dinges and other scientists have
shown that cognitive performance and vigilant attention begin
to decline fairly quickly after more than 16 hours of continuous
wakefulness, and that sleep deficits from partial sleep deprivation can accumulate over time, resulting in a steady deterioration in alertness. The widely used psychomotor vigilance
test (PVT), a simple neurocognitive test developed by Dr.
Dinges and colleagues that assesses an individual’s ability to
sustain attention and respond to signals in a timely manner,
has proven to be an exceptionally sensitive tool for capturing
dose–response effects of sleep loss on neurobehavioral functioning.13 The PVT also reliably detects sleep deficits caused
by disrupted or fragmented sleep, and/or poorly timed sleep,
which is important because a growing body of evidence suggests that the continuity and timing (or circadian alignment)
of sleep may be as important as the total amount of time spent
“We know that sleep is much more restorative of waking functions and health when it is consolidated and not fragmented,”
explains Dr. Dinges. “That is, when sleep goes through the
appropriate physiological sequences of non-REM (rapid eye
movement) and REM states at night, and occurs when human
sleep is temporally programmed by our circadian clock to occur.
David F. Dinges, PhD
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The Extraordinary Importance of Sleep
Such consolidated sleep is typical of a longer duration and
better sleep quality than sleep taken at other times of the day,
such as that which occurs with nightshift work, jet lag, and
other conditions of circadian misalignment.”
Dr. Dinges and his colleagues have found that people whose
daily sleep duration is inadequate, or repeatedly disrupted
(e.g., by obstructive sleep apnea, restless legs syndrome,
pain or stress, or shiftwork or jet lag), often are not aware of
their accumulating sleep deficits or the toll that these deficits
can take on their waking cognitive functions, including their
performance, working memory, cognitive speed, and accuracy.
Inadequate sleep also can take a toll on psychological wellbeing, significantly affecting our emotional and psychosocial
interpretation of events and exacerbating our stress levels.
Studies have indicated that changes in mood may be due in
part to the effects of sleep deprivation on the processing of
emotional memory––in other words, our tendency to select
and remember negative memories after inadequate sleep.14
In one study conducted by Dr. Dinges and colleagues,
participants’ mood was observed after they were confronted
with “high” and “low” performance demands, following varying
degrees of sleep deprivation.15
“To our surprise, those who were sleep-deprived responded
to low stressors in much the same way that people without
any sleep deprivation tended to respond to high stressors,”
said Dr. Dinges. “In other words, we tend to become much
more sensitive emotionally and socially when we are sleepdeprived. That is what I like to call the ‘who was at my desk
or who touched my coffee cup?’ phenomenon. I think we all
have experienced having an extreme reaction or a very negative emotional response to a mild stressor when we have not
had enough sleep.”
Aiming for the Sweet Spot
How much sleep is enough? After decades of investigation,
it appears that scientists have gathered enough evidence to
begin to answer that question.16
“When duration of sleep drops below seven hours, and
especially when it starts to move toward six and half hours
or less, a number of different disorders begin to increase in
prevalence,” says Dr. Dinges. “Most experts would agree that
there is a kind of sweet spot that most people should aim for,
and for the average healthy adult that zone is ideally somewhere
between 7 and 7 and a half hours. That is what the consensus
evaluations of more than a thousand scientific articles have
yielded––the consensus of evaluations conducted by the AASM
(American Academy of Sleep Medicine) and Sleep Research
Society jointly.”
Numerous large U.S. surveys––beginning with a 1982 survey
by the American Cancer Society—have been used to estimate
the number of hours that most people spend sleeping. Many
surveys have identified a worrisome prevalence of “short”
sleepers (people who sleep 6 hours or less) among respondents, and a general trend toward decreasing sleep duration
between 1975 and 2006. More recently, however, an analysis
of the American Time Use Survey (ATUS), spearheaded by
Mathias Basner, MD, PhD, at the University of Pennsylvania17,
has suggested that there may be cause for optimism.
“The analysis shows that there is a slight but steady increase
in sleep time that stretches back to about 2003 or 2004,” says
Dr. Dinges. “We think this increase, which is modest––at most
a minute or two more per year––is due in part to the development of the field of sleep medicine, and public and scientific
reports in the media about sleep loss contributing to accidents
and catastrophes, and so forth. Ever so slowly, the message that
it is important not to get sleep deprived, and to get help if you
have a sleep disorder, has begun to penetrate to the public.”
The analysis notes that one sign of greater interest in sleep on
the part of the public has been a significant increase in Google
searches containing the word “sleep” since 2004. Data from the
ATUS also suggest that over time, people have been willing to
trade some of their daily activities in exchange for more sleep.
It is important to note, says Dr. Dinges, that self-reports of time
spent sleeping are not always accurate––they can be off by a
half an hour or more, usually with people tending to estimate
that they slept more than they did. He also notes that there is
still a fairly large population sleeping 6 hours or less.
“Although there are signs that sleep time is increasing, it is
not happening at nearly the dramatic rate that most experts
would like to see,” says Dr. Dinges. “This is especially true
for vulnerable populations. There is concern about school
start times and bus times affecting the sleep of children and
adolescents, and about extracurricular activities at the end of
the school day sometimes leading to a delay in bed times for
teenagers. All of this is an ongoing, evolving picture, with more
research results coming out all the time, and with consequent
changes in recommendations, to make sure that at least our
most vulnerable populations are getting adequate sleep.”
Interindividual Differences in Vulnerability to Sleep Loss
While it is well established that the effects of sleep loss
accumulate over time, with repeated exposure to inadequate,
fragmented, or disrupted sleep, the degree to which individuals demonstrate adverse effects of inadequate sleep can vary
“We have learned that there are astonishingly mysterious
phenotypes, or trait-like differences, in how vulnerable people
are to sleep loss,” says Dr. Dinges. “This is still a relatively
new area of research, and it has only been in the past few
years that scientists have begun to replicate early findings
regarding these phenotypic differences in vulnerability to the
negative neurobehavioral effects of sleep loss. The interindividual differences that have been observed so far raise some
extremely provocative scientific questions. We may find that
there is something in waking biology that can substitute for, or
somehow reduce, the impact of sleep loss on waking functioning, but thus far there is no evidence as to what that might be.”
Differences among individuals exist with regard to both the
effects of sleep loss and the ability to recover from the effects of
sleep loss. Differences in performance also have been shown to
be task-dependent, suggesting that people who are vulnerable
to the effects of sleep loss in one or more cognitive or neurobehavioral domains may be resistant to the effects of sleep
loss in others. To better understand interindividual variability,
scientists are investigating possible genetic mechanisms that
may underlie complex interactions between circadian and sleep
homeostatic systems—the systems that affect our drive for
sleep as well as our alertness and performance during waking
760 P&T® • December 2018 • Vol. 43 No. 12
hours. A current goal is to discover biomarkers that may help
predict individual performance after varying degrees of sleep
loss.19 And one hope is that biomarkers––ideally in the form of
a simple “roadside” test such as a breathalyzer––may eventually
be used to detect sleep loss-related impairment in drivers or in
individuals responsible for operating sophisticated equipment
or machinery. To date, no viable candidates have been found.
Investigators also are shedding light on the role that age
may play in resilience to sleep loss. The results of one recent
study indicate that younger adults are more vulnerable to the
adverse effects of chronic sleep loss and recurring circadian
disruption than older adults.20 Although the neurobiological
basis for these age-related differences is not yet understood,
such findings may help to inform new approaches to the prevention of drowsy driving and related motor-vehicle accidents
among young drivers.
Dr. Dinges emphasizes that findings regarding interindividual differences in response to sleep loss and in recovery
from sleep loss should not diminish the message that adequate
sleep is critical for everyone.
“Research has shown us that sleep is not an optional activity,”
says Dr. Dinges. “There is no question that sleep is fundamentally conserved across species and across lifespans, and that
any effort to eliminate it has been unsuccessful. We must plan
our lives in the time domain with a serious consideration for
sleep––planning when to sleep, ensuring that we get adequate
sleep, and making sure that our sleep is not disturbed by
disorders or diseases, whether or not they are sleep-related.”
Addressing Sleep Disorders
As connections between sleep disruption and both disease
and mortality have become more firmly established, accurate
and efficient diagnosis and management of sleep disorders (see
Table 1) have become increasingly critical. Recent directions
in the field of sleep medicine include a move toward patientcentered care, greater collaboration between specialists and
primary care physicians, and the incorporation of new tools––
including home-based diagnostic tests and novel electronic
questionnaires––in the effort to create a comprehensive yet
The Extraordinary Importance of Sleep
more personalized approach to assessment and treatment.
A chief goal is to improve the diagnosis of sleep disorders.
Although approximately 70 million people in the U.S. have at
least one sleep disorder, experts estimate that up to 80% of
sleep disorders may go undetected or undiagnosed. One major
challenge that clinicians face during the initial assessment of
people with sleep disorders is the process of identifying and
sorting out comorbidities. Untangling the causes and effects
in bidirectional comorbidities can be particularly difficult. For
example, insomnia––by far the most common sleep disorder––
often is complicated by the presence of another sleep disorder,
such as sleep apnea or restless legs syndrome.
“Some experts have even suggested that all cases of insomnia
coexist with, or are caused by, another sleep disorder, most
commonly sleep apnea,” says Clete A. Kushida, MD, PhD,
Professor of Psychiatry and Behavioral Sciences at Stanford,
and Division Chief and Medical Director of Stanford Sleep
Medicine. “I’m not sure I would go quite that far, but certainly
bidirectional comorbidities among individuals who experience
sleep disorders are common. For example, pain syndromes––
including back pain and limb pain, especially among older
patients––are common comorbidities in patients with insomnia.
Mood disorders also frequently occur in patients who experience insomnia.”
Comorbidities can complicate treatment and often require
sleep specialists to collaborate with not only primary care
physicians but also specialists in other therapeutic areas.
“If, for example, a person with insomnia also has been diagnosed with depression by a psychiatrist,” says Dr. Kushida,
“our goal is to work hand in hand with the psychiatrist to find
the right medication. There are both sedating and alerting
antidepressants, and a patient may need to try one medication
for a couple of weeks to months, slowly increasing the dose to
a therapeutic level, until the effect on both the depression and
the patient’s sleep can be determined. For some individuals,
an alerting antidepressant can cause poor sleep, which in turn
can exacerbate the depression. The process of achieving the
right dose of the right medication can be complex, and benefits
from a collaboration between specialists.”
Table 1 ICSD-3 Major Diagnostic Sections *
Insomnia Difficulty getting to sleep or staying asleep, with associated daytime consequences.
Sleep-related breathing disorders Obstructive sleep apnea (cessation of breathing due to upper airway obstruction), central sleep apnea
(cessation of breathing due to absent respiratory effort), and hypoventilation disorders (shallow breathing
due to a variety of medical conditions).
Central disorders of hypersomnolence
Excessive daytime sleepiness not due to other sleep disorders. These include narcolepsy, idiopathic hypersomnolence, and insufficient sleep syndrome.
Circadian rhythm sleep–wake
Abnormalities of sleep–wake cycles due to misalignment between the biological clock and customary or
required sleep–wake times. These include delayed or advanced sleep phase, shift work disorder, and jet
Parasomnias Abnormal behaviors or events arising from sleep. These include sleepwalking, sleep terrors, and rapid
eye-movement sleep behavior disorder.
Sleep-related movement disorders Abnormal, usually stereotyped, recurring movements in sleep. Restless legs syndrome, although a waking
sensory disorder, is included, as well as periodic limb movement in sleep and leg cramps.
Other sleep disorders Those sleep–wake disorders not classified elsewhere, most notably environmental sleep disorder.
*Table courtesy of Michael J. Sateia, MD
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The Extraordinary Importance of Sleep
Undetected obstructive sleep apnea (OSA) in patients with
chronic pain, or other serious illnesses, can result in potentially
dangerous comorbidities. Opioids, for example, are known to
have adverse effects on respiration, and can lead to central
sleep apnea (CSA)––shallow and irregular or interrupted
breathing and sustained hypoventilation––a potentially lethal
condition that can intensify the consequences of OSA. These
risks underscore the need to improve methods for identifying
and properly diagnosing the estimated 23.5 million U.S. adults
with OSA. Public education and advocacy efforts are already
helping to improve detection––in part by helping to address
misconceptions about OSA.
“One of the biggest misconceptions is that only people who
are significantly overweight experience sleep
apnea,” says Dr. Kushida. “In fact, only up to
67% of people who have OSA are overweight,
the rest are of normal weight. OSA also can be
caused by craniofacial dysmorphism, or a defect
of the airway that occurs during development.
A narrow airway caused by deficient growth
of the craniofacial skeleton, particularly the
jaws, can become narrower and more prone
to collapse with age, leading to sleep apnea.”
Treating Insomnia: The Value of Cognitive
Behavioral Therapy
Insomnia, the most prevalent sleep disorder,
affects approximately one third of all adults and
is the most common condition that family and primary-care physicians encounter. According to the International Classification
of Sleep Disorders (ICSD-3), chronic insomnia is the inability
to attain sufficient sleep (despite adequate opportunity) for at
least three nights per week for three months or longer, with
negative daytime consequences. For most people, the disorder
is transient, but for approximately 10% to 15% of those who
experience insomnia (around 30 million people) it becomes
chronic. Although pharmacologic treatments for insomnia
(Table 2) can be effective, most experts now recommend
against the long-term use of pharmacotherapy.
“If a person has been diagnosed with chronic insomnia,
the only treatment that has been shown to have long-term
benefit is cognitive behavioral therapy, “says Dr. Kushida.
“Medications really should be considered short-term treatments, because patients tend to develop dependence on, or
tolerance to, hypnotic drugs. In our clinic, we commonly see
that, over time, medications stop having an effect, and that
means that patients may try higher doses of a medication, or
keep switching to different medications. So, medications are a
temporary solution––they just put a Band-Aid on the problem
of insomnia, whereas cognitive behavioral therapy targets one
of the pathways toward success.”
Cognitive behavioral therapy (CBT), which involves techniques that work in part by reducing cognitive and somatic
arousal, is estimated to be effective in approximately 70% to
80% of people who experience chronic insomnia. Dr. Kushida
notes that while drugs can sometimes be useful in the treatment of acute insomnia, they become problematic after acute
insomnia transitions to chronic insomnia.
“A person might be an OK sleeper for several years, and
then suddenly experience a traumatic event, such as the loss
of a job, a divorce, or the death of a loved one, resulting in very
poor sleep,” says Dr. Kushida. “Down the road, that person
might obtain a better job, overcome grief, or find a new relationship, but continue to experience insomnia. We think in some
cases the transition from acute insomnia to chronic insomnia
occurs because the behavioral event triggers something in
the person’s physiology that may lead to long-term changes.
Once they are in a chronic insomnia phase, we tell patients
that CBT is the only truly effective intervention.”
If a patient is already taking hypnotics, Dr. Kushida says
that he will gradually wean the patient off medications while
introducing CBT. He notes that often it is necessary for sleep
specialists to manage the expectations of
chronic sufferers.
“We sometimes have to let patients with
chronic insomnia know that we may never
get them back to where they were when they
had optimal sleep,” Dr. Kushida explains. “The
behavioral methods we use work well, and
usually we can get patients to the point where
the insomnia is having less of an impact on their
quality of life. Our inability to completely restore
the patient’s ability to sleep well may partly
be explained by as yet unidentified changes
in his or her neurophysiology or neurochemistry. Some patients with chronic insomnia
can begin to sleep normally again, but for the
vast majority, we aim to make insomnia less of a burden on a
patient’s daily life.”
Improving Clinical Research
In the field of sleep medicine, as in many other therapeutic
areas, future directions in clinical trial research will place
an emphasis on patient engagement and patient-centered
“Perhaps the most important aim these days when developing and implementing any type of large-scale clinical research
study is to incorporate the patient’s perspective,” says Dr.
Kushida, who is currently analyzing the results of a comparative
effectiveness sleep study sponsored by the Patient-Centered
Outcomes Research Institute (PCORI).22 The study, designed
and conducted by a team at Stanford, introduced a new model
of patient-centered, coordinated care and tested it against
conventional outpatient treatment for sleep disorders.
“The patient’s perspective is so invaluable in guiding the
success of a study that ideally it should be incorporated right at
the inception of a research question or idea,” says Dr. Kushida.
“When you are designing an especially complicated trial, for
example, it is easy to incorporate a lot of tests and measures
without being aware of the burden these can place on the
participants. It’s critical to learn from patients whether they
are overwhelmed by the number of tests, or whether travel
time or the amount of time they need to take off from work
may be impractical.”
Other efforts to improve clinical research include those
focused on correcting for and/or eliminating several confounding variables that tend to plague sleep research. The surprising
power of the placebo effect,23 the related disconnect between
Clete A. Kushida, MD, PhD
762 P&T® • December 2018 • Vol. 43 No. 12
objective and subjective evaluations of sleep loss and recovery
from sleep loss, variable adherence to treatments, and, more
recently, deceptive practices among clinical trial participants,
are a few examples.
The placebo effect, which refers to any outcome that may
be attributable to the expectations of clinical trial participants
rather than to the drug or device being tested, can be especially
problematic in experimental protocols that involve self-reports
of sleep quality.
“Clinical trials involving patients with disorders such as
insomnia or RLS that rely solely on subjective measures, or
ratings of severity based on patient report, are particularly
vulnerable to the placebo effect,” says Dr. Kushida. “It has
been demonstrated that when these patients believe that
they are receiving the study drug or device the likelihood of
their experiencing a positive effect can increase significantly.
There have been efforts to develop or introduce new objective
endpoints in these studies, which may help with this problem.”
Achieving the right balance of subjective and objective
measures of sleep is an important goal in both research and
clinical practice. The current gold standard for objective
assessment of sleep is polysomnography
(PSG), which includes electrophysiological recordings of brain activity (EEG),
muscle activity (EMG), and eye movements (EOG). A valuable, non-invasive
method for determining sleep continuity
and sleep architecture, PSG has been an
indispensable objective endpoint in clinical
trials, but it is expensive and not always
practical. Novel approaches to objective
measurement, including actigraphy, which
may be used to help minimize recall bias
and complement subjective measures of
sleep (e.g., sleep logs or diaries), still have
“The problem with wearable devices
right now,” says Dr. Kushida, “is that they
tend to overestimate sleep, sometimes by
as much as an hour. They also are not yet
capable of accurately detecting different
stages of sleep, such as non-REM and REM
sleep. Because of our proximity to Silicon
Valley, our laboratory tests a lot of these
new devices, and often by the time we
have finished testing one prototype, new
ones have emerged. The product cycles
are rapid, and the companies keep incorporating newer and newer technology.
So, down the road, within about five to
ten years, I think these devices will likely
estimate sleep and detect sleep stages with
Also, objective tools are needed for
addressing problems with adherence to
treatment. One important current aim is to
detect and correct for non-obvious factors
that result in failure to adhere to treatment, whether unintended or deliberate,
to ensure that trial outcomes accurately reflect the efficacy of
a drug, medical device, or behavioral intervention.25 A related
problem is deliberate deception by trial participants. As part of
a National Heart, Lung, and Blood Institute (NHLBI)-supported
study focused on detecting and correcting for adherence problems, Dr. Kushida and colleagues began to explore the prevalence of deceptive practices among clinical trial participants.26
“We found that deception among clinical trial participants
is pretty common and that there is quite a range of deceptive
practices, “says Dr. Kushida. “They include underreported drug
holidays, fabrication or withholding of medical histories, pill
dumping, exaggerated symptoms, and falsification of current
health status. It’s important that we find a way to address these
deceptive practices because both the integrity of research data
and the safety of participants are at risk.”
Dr. Kushida adds that newer tools, such as electronic monitoring of pill dispensing and statistical predictive adherence
models, may uncover and remedy pressing problems related
to adherence and deceptive practices. “It already takes about
12 years for a new drug to be approved, and about three to
five years for a new device to be approved. When deceptive
The Extraordinary Importance of Sleep
Table 2 Selected Pharmaceutical Treatments for Insomnia21, 27
Agent (Generic Name) Dosage Forms Indications/Comments
Eszopiclone 1-mg, 2-mg, and 3-mg
Primarily used for sleep-onset and
maintenance insomnia; intermediateacting; no short-term usage restriction
Zolpidem 5-mg, 10-mg tablets Primarily used for sleep-onset insomnia;
short- to intermediate-acting; primarily
used for sleep-onset and maintenance
insomnia; controlled-release
Zaleplon 5-mg, 10-mg capsules Primarily used for sleep-onset insomnia;
maintenance insomnia as long as a
4-hour period is available for further
sleep; short-acting
Estazolam 1-mg, 2-mg tablets Short- to intermediate-acting
Temazepam 7.5-mg, 15-mg, and
30-mg capsules
Short- to intermediate-acting
Triazolam 0.125-mg, 0.25-mg
Flurazepam 15-mg, 30-mg capsules Long-acting; risk of residual daytime
Melatonin Receptor Agonists (Non-Scheduled)
Ramelteon 8-mg tablet Primarily used for sleep-onset insomnia;
short-acting; no short-term usage
Orexin Receptor Antagonist
Suvorexant 5-mg, 10-mg, 15-mg, and
20-mg tablets
Indicated for the treatment of insomnia
characterized by difficulties with sleep
onset and/or sleep maintenance.
Lowest effective dose should be used.
Vol. 43 No. 12 • December 2018 • P&T® 763
practices are discovered too late, it can lead to the invalidation
of research findings and further delays in approving muchneeded treatments.”
Enhancing clinical research in the field will require a cooperative, international effort focused on advancing knowledge
about sleep, circadian rhythms, and sleep disorders worldwide.
During Dr. Kushida’s tenure as inaugural president of the World
Sleep Society (WSS), he led an initiative to create international
sleep fellowships to prepare physicians and scientists from
various countries for future leadership roles in basic and/or
clinical sleep research. He also oversaw the development of
an International Sleep Research Network, designed to help
sleep scientists and clinicians find collaborators with similar
clinical/research interests. As the WSS continues to offer new
services and expand its programs, it will be with an awareness
of the needs of disadvantaged populations and the importance
of access to appropriate treatment.
“One initiative of the WSS involves reviewing current published guidelines in various countries, to determine whether
they meet international standards,” says Dr. Kushida. “Many
guidelines are region-specific and list only medications approved
in specific countries or regions. As we review the guidelines,
we endorse them with caveats; we may note that particular
treatments for insomnia are recommended, and when these
are not available we recommend acceptable substitutes. The
goal is to ensure that specialists can use practice guidelines
in whichever country they practice sleep medicine, and that
patients are receiving the best possible treatment available.”
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