Supplement
Insomnia: prevalence, consequences and
effective treatment
David Cunnington
MB BS, MMedSc, FRACP,
Sleep Physician and
Director 1
Moira F Junge
BA, BAppSc(Hons), DPsych
(Health),
Psychologist 1
Antonio T Fernando
MD, FRANZCP, Senior
Lecturer 2
1 Melbourne Sleep Disorders
Centre, Melbourne, VIC.
2 Department of
Psychological Medicine,
University of Auckland,
Auckland, NZ.
david.cunnington@
msdc.com.au
MJA 2013; 199: S36–S40
doi: 10.5694/mja13.10718
I
nsomnia is a very common disorder that has significant long-term health consequences. Australian population surveys have shown that 13%–33% of the adult
population have regular difficulty either getting to sleep
or staying asleep.1,2 Insomnia can occur as a primary
disorder or, more commonly, it can be comorbid with
other physical or mental disorders. Around 50% of
patients with depression have comorbid insomnia, and
depression and sleep disturbance are, respectively, the
first and third most common psychological reasons for
patient encounters in general practice.3 Insomnia doubles
the risk of future development of depression, and insomnia symptoms together with shortened sleep are associated with hypertension.4,5
Insomnia is defined in the fifth edition of the Diagnostic
and statistical manual of mental disorders (DSM-5) as difficulty getting to sleep, staying asleep or having nonrestorative sleep despite having adequate opportunity for
sleep, together with associated impairment of daytime
functioning, with symptoms being present for at least 4
weeks.6 Having a sleep experience that does not meet our
expectation, such as with some transient awakenings but
with good daytime functioning, does not constitute
insomnia.
Acute versus chronic insomnia
Acute insomnia is defined as sleep disturbance meeting
the DSM-5 definition of insomnia, but with symptoms
occurring for less than 4 weeks.6 Generally, acute insomnia is triggered by precipitating events such as ill health,
change of medication or circumstances, or stress. Once
the precipitating event passes, sleep settles back to its
usual pattern. Hence, treatment for acute insomnia is
focused on avoiding or withdrawing the precipitant, if
possible, and supporting the acute distress of not sleeping with short-term use of hypnotics if symptoms are
significant. This is the usual approach in primary care,
with 95% of general practitioner consultations for insomnia resulting in the prescription of a hypnotic, usually a
benzodiazepine.7
However, if patients have repeated episodes of acute
insomnia or ongoing comorbidities, insomnia symptoms
can persist and evolve into chronic insomnia, which
requires a different treatment approach. Once people
have had difficulty sleeping for over 4 weeks, they have
usually begun to behave and think about sleep differThe Medical ently,
Journalin of
Australia
ways
that are ISSN:
maladaptive and perpetuate their
0025-729X 21 October
2013 19988The
36-40
sleep difficulties.
long-term course is then generally
©The Medicalone
Journal
of Australia
2013
of relapse
and remission
rather than resolution,9
www.mja.com.au
which continues well after the acute precipitating circumSupplement
stances have passed. Therefore, the treatment approach
needs to match this, with a chronic disease management
model educating and upskilling patients on how best to
Online first 17/10/13
manage their insomnia symptoms over time. Health care
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MJA 199 (8) · 21 October 2013
Summary
• Insomnia is common and can have serious
consequences, such as increased risk of depression and
hypertension.
• Acute and chronic insomnia require different
management approaches.
• Chronic insomnia is unlikely to spontaneously remit, and
over time will be characterised by cycles of relapse and
remission or persistent symptoms.
• Chronic insomnia is best managed using non-drug
strategies such as cognitive behaviour therapy.
• For patients with ongoing symptoms, there may be a
role for adjunctive use of medications such as hypnotics.
providers need to see insomnia as a chronic illness and
emphasise the role of strategies to prevent relapses,
rather than focusing on treatment of acute episodes or
crises.
Assessment and diagnosis of insomnia
The assessment and diagnosis of insomnia is formulated
mainly from a systematic sleep history. To assist in
establishing premorbid baseline sleeping patterns and
formulating treatment goals, clinicians must ask patients
about their typical sleeping pattern before they developed
insomnia.
Insomnia assessment involves understanding the
patient’s typical sleep pattern at night and over a time
frame of weeks to months. Therefore, part of the sleep
assessment is asking for the patient’s narrative of typical
bedtime, time taken to fall asleep after lights out (sleep
latency), frequency and rough duration of awakenings in
the middle of the night, and what time the patient gets
out of bed. Are there times when sleep returns to normal?
Was there an initial trigger or did the symptom arise
spontaneously? Was it related to a period of stress,
anxiety or depression? Did it start during childhood and
continue thereafter? Are there lifestyle factors contributing to insomnia, such as too much caffeine or exercise
late in the day, television or pets in the bedroom, or use of
alcohol or nicotine? Knowing the patient’s cognitions,
beliefs and worries about sleep, which are often apparent
in the language and emotion used when they describe
their sleep, can assist in the formulation of specific
behavioural and calming approaches to assist with sleep.
It is important to assess the effects of poor sleep on the
patient. Common daytime consequences include mood
lowering, irritability, poor memory, fatigue, lack of energy
and general malaise. These can manifest as work absenteeism, with insomnia being one of its leading medical
causes.10 It is also imperative to ask for risky consequences of insomnia, including accidents and sleepiness while driving.
Sleep disorders
Identifying the body clock type of the patient is crucial
in excluding circadian rhythm disorders. A commonly
undiagnosed condition, delayed sleep phase disorder is a
body clock variation where the patient is biologically
inclined to go to sleep much later than usual (typically
after midnight), yet generally sleeps well after sleep
onset, with a natural wake time that is much later than
for most people and is often incompatible with normal
school or work start times.
It is also important to look for comorbid conditions
that can present with insomnia, such as depression and
anxiety, chronic medical conditions, and other sleep
disorders. Comorbid conditions have a bidirectional
relationship with insomnia, with each influencing or
exacerbating the other and requiring concurrent assessment and management. The Auckland Sleep Questionnaire, a validated sleep screening questionnaire in
primary care, is one tool that can assist in identifying
these disorders.11 Other validated questionnaires such as
the Insomnia Severity Index can help to document the
severity of patients’ symptoms and assess their response
to treatment.12
Since many people with insomnia overestimate their
sleep disruption and underestimate actual sleep time, a
2-week sleep diary is a very helpful assessment tool as it
assists the sleep clinician to get a more accurate snapshot
of sleep compared with a pure verbal account.13 For
some, a sleep diary is revealing in that they realise that
they do get some sleep, albeit fragmented or superficial.
This can provide the basis for discussion. There are
several downloadable sleep diaries online — for example,
http://yoursleep.aasmnet.org/pdf/sleepdiary.pdf. If
patients have difficulty completing a sleep diary, or there
is significant misperception of sleep suspected, actigraphy (using a device worn on the wrist to monitor sleep–
wake cycles) can be used to objectively measure sleep.
Although an overnight sleep study or polysomnography is not routinely indicated in diagnosing insomnia, it
can be helpful in diagnosing several conditions, including
obstructive sleep apnoea, sleep-related movement disorders, parasomnias, or insomnias that are treatmentresistant.13 A routine physical and mental status examination can give clues regarding comorbid medical and or
mental health conditions. Other tests including laboratory and radiographic procedures are not routinely indicated in chronic insomnia.13
Non-pharmacological treatment of insomnia
Cognitive behaviour therapy aimed at treating insomnia
(CBT-i) targets maladaptive behaviour and thoughts that
may have developed during insomnia or have contributed
to its development. CBT-i is considered to be the gold
standard in treating insomnia, with effect sizes similar to
or greater than those seen with hypnotic drugs and,
unlike with hypnotics, maintenance of effect after cessation of therapy.14,15 These effects are seen in both primary
and comorbid insomnia.16
The implementation of individual face-to-face CBT-i is
typically delivered by a trained health professional, which
makes it expensive, labour intensive and therefore
beyond the reach of many. Patients with insomnia are
eligible for Medicare rebates for psychological treatment
if they are referred under the Chronic Disease Management or Better Access to Mental Health Care initiatives.
Telephone and online delivery of CBT-i have been shown
in clinical trials to be as effective as face-to-face CBT-i.17,18
While these different treatment delivery models have the
potential to markedly improve access to CBT-i, they need
to be investigated further with respect to their long-term
reliability and effectiveness. They might be best used as
part of a stepped-care approach.19 Some patients may
need little guidance, while others may need more personal treatment and guidance.
CBT-i consists of five major components: stimulus
control, sleep restriction (also known as sleep consolidation or bed restriction), relaxation techniques, cognitive
therapy and sleep hygiene education (Box). Typically,
CBT-i is delivered in four to 10 sessions, either individually or in a group setting, ideally involving four to eight
participants.
Stimulus control is a reconditioning treatment forcing
discrimination between daytime and sleeping environments.20 For the poor sleeper, the bedroom triggers
associations with being awake and aroused. Treatment
involves removing all stimuli that are potentially sleepincompatible (reading, watching television and use of
computers) and excluding sleep from living areas. The
individual is instructed to get up if he or she is not asleep
within 15–20 minutes, or when wakeful during the night
or experiencing increasing distress, and not return to bed
until feeling sleepy.
Sleep restriction relates to better matching the time
spent in bed to the average nightly sleep duration.21
Patients keep a sleep diary to determine average sleep
duration. They are then allowed a period of time in bed
equal to this plus 30 minutes, and set a regular arising
time. As some patients can underperceive the amount of
sleep, the time in bed should never be set at less than 5
hours. As sleep becomes more consolidated, the length of
time in bed can be gradually increased in 15–30 minute
increments. This effective intervention induces natural
sleepiness (reduced time in bed) and gives the individual
a sense of assurance that bed is now a safe place to sleep.
Bed restriction has recently been shown to be an effective
intervention in primary care.22
Relaxation techniques include progressive relaxation,
imagery training, biofeedback, meditation, hypnosis and
autogenic training, with little evidence to indicate superiority for any one approach. Patients are encouraged to
practice relaxation techniques throughout the day and
early evening. Even a few minutes two to four times a day
is useful. A last-minute relaxation attempt minutes before
sleep will not work miracles. Muscular tension and cognitive arousal (eg, a “chattering” mind) are incompatible
with sleep. At the cognitive level, these techniques may
act by distraction. Relaxation reduces physical and mental
arousal but is less effective as a stand-alone treatment
and is better used in combination with other treatment
interventions.
MJA 199 (8) · 21 October 2013
S37
Supplement
Cognitive behaviour therapy for insomnia
Intervention
General description
Specific instructions
Stimulus control
BED = SLEEP. Set of instructions aimed at conditioning the
patient to expect that bed is for sleeping and not other
stimulating activities. Only exception is sexual activity. Aim is
to promote a positive association between bedroom
environment and sleepiness
Go to bed only when sleepy/comfortable and intending to fall asleep. If unable to
sleep within what feels like 15–20 minutes (without watching the clock), leave the
bed and bedroom and go to another room and do non-stimulating activity. Return
to bed only when comfortable enough to sleep again. Do not read, watch television,
talk on phone, pay bills, use electronic social media, worry or plan activities in bed
Sleep-restriction
therapy
Increases sleep drive and reduces time in bed lying awake.
Limits the time in bed to match the patient’s average
reported actual sleep time. Slowly allows more time in bed
as sleep improves
Set strict bedtime and rising schedule, limited to average expected hours of sleep
reported in the average night. Increase time in bed by 15–30 minutes when the time
spent asleep is at least 85% of the allowed time in bed. Keep a fixed wake time,
regardless of actual sleep duration
Relaxation techniques
Various breathing techniques, visual imagery, meditation
Practise progressive muscle relaxation (at least daily). Take shorter relaxation
periods (2 minutes) a number of times per day. Use breathing and self-hypnosis
techniques
Cognitive therapy
Identifies and targets beliefs that may be interfering with
adherence to stimulus control and sleep restriction. Uses
mindfulness to alter approach to sleep
Unhelpful beliefs can include overestimation of hours of sleep required each night
to maintain health; overestimation of the power of sleeping tablets;
underestimation of actual sleep obtained; fear of stimulus control or sleep
restriction for fear of missing the time when sleep will come
Sleep hygiene
education
Emphasises environmental factors, physiological factors,
behaviour, habits that promote sound sleep
Avoid long naps in daytime — short naps (less than half an hour) are acceptable.
Exercise regularly. Maintain regular sleep–wake schedule 7 days per week
(particularly wake times). Avoid stimulants (caffeine and nicotine). Limit alcohol
intake, especially before bed. Avoid visual access to clock when in bed. Keep
bedroom dark, quiet, clean and comfortable
Cognitive therapy involves enabling the patient to
recognise how unhelpful and negative thinking about
sleep increases physiological and psychological arousal
levels. Setting aside 15–20 minutes in the early part of the
evening to write down any worries, make plans for the
following day and address any concerns that might arise
during the night allows the day to be put to rest. It is
helpful to challenge thoughts that arise at night with “I
have already addressed this and now I can let go of it!”.
“Time out” — some form of soothing activity before bed
— can be useful in reducing arousal levels. Thoughtstopping attempts or blocking techniques, such as
repeating the word “the” every 3 seconds, occupy the
short-term memory store (used in processing information), potentially allowing sleep to happen. Cognitive
restructuring challenges unhelpful beliefs, such as “if I
don’t get enough sleep tonight, tomorrow is going to be a
disaster”, which maintain both wakefulness and helplessness. Another cognitive and behavioural technique is
paradoxical intention. Clients are encouraged to put the
effort into remaining wakeful rather than trying to fall
asleep (decatastrophising), thereby strengthening the
sleep drive and reducing performance effort.14
There is limited evidence to suggest that, on its own,
sleep hygiene is efficacious.14 However, it is an essential
component of CBT-i and involves “cleaning up” or
improving an individual’s sleep environment and behaviour to promote better sleep quality and duration.23
Mindfulness and insomnia
In recent years, the technique of mindfulness has become
increasingly popular and is likely to be efficacious in
helping to promote sleep by reducing cognitive and
physiological arousal. Mindfulness treatment interventions have demonstrated statistically and clinically significant improvements in several night-time symptoms of
insomnia, as well as reductions in presleep arousal, sleep
S38
MJA 199 (8) · 21 October 2013
effort and dysfunctional sleep-related cognitions.24 In
many cases, mindfulness is combined with CBT-i.24,25 As
an adjunct to CBT-i, it can be used for psychoeducation to
help the client develop a more functional schematic
model of sleep and for dealing with sleeplessness, including the detrimental role of hyperarousal. Typically, the
chattering mind is focused on past or future events,
whereas mindfulness emphasises being non-judgemental in the present, which potentially can reduce mind
activation.
Bright light exposure (natural or artificial)
Educating the patient about sleep and the importance of
bright light is an important aspect of treating insomnia.
Good objective information about sleep, sleep loss and
the body clock are helpful starting points for self-management. Bright light is a potent synchroniser for human
circadian rhythm. In particular, morning light, which can
be combined with exercise such as walking, can be
helpful in consolidating night-time sleep and reducing
morning sleep inertia.26
Pharmacological treatment of insomnia
Although psychological and behavioural interventions
are indispensable and effective for most insomnia sufferers, some will still need the extra help from pharmacological agents. Current medications and natural products
used for insomnia include benzodiazepine-receptor agonists, melatonin and variants, antidepressants, antipsychotics and antihistamines.
Hypnotic drugs that act on the -aminobutyric acid
receptor include benzodiazepines, such as temazepam, as
well as the benzodiazepine-receptor agonists, such as
zopiclone and zolpidem. Medications of this group have
been studied in randomised controlled trials, with efficacy over 6 months27 and longer in open-label exten-
Sleep disorders
sions.28 Many doctors avoid prescribing medications from
this family, mainly because of concern regarding dependence and tolerance. However, long-term trials of eszopiclone (not available in Australia) and extended-release
zolpidem have shown sustained response with no tolerance and dependence after 6 months of daily use.27-29
Despite these findings, the concern remains that there
are vulnerable patients who may become dependent on
hypnotic drugs. To limit the risk of tolerance and dependence, the prescriber can instruct the patient to use the
medication on a scheduled basis; for example, only on
alternating nights, or three times a week and at the
lowest effective dose possible for a limited time (ie, a
month).27 Zolpidem has been associated with parasomnias, so clinicians need to warn patients about unusual
sleep behaviours as a side effect. Sudden discontinuation
of this class of medications can result in a rebound
insomnia that can be mitigated by a gradual taper.
Despite the similarity in the mode of action and
pharmacokinetics of these agents, patients react differently to each product. Lack of response to one agent does
not mean that others of the same group will not work.
Similarly, an adverse effect of one does not mean that
others will cause the same reaction. The decision whether
or not to prescribe hypnotics should rely on a careful risk–
benefit analysis by both the doctor and the patient. In
addition to the perceived risk of dependence and tolerance, clinicians should consider the risks of untreated
insomnia.
Melatonin has been shown to be effective in treating
insomnia, particularly among people aged over 55
years.30 However, melatonin is more effective as a
chronobiotic for treating body clock conditions like jetlag
and delayed sleep phase disorder than as a treatment for
chronic insomnia.31
Sedating antidepressants (eg, doxepin, amitriptyline,
mirtazapine, trimipramine), sedating antipsychotics (eg,
quetiapine, olanzapine) and antihistamines are used offlabel as sleep medications, despite insufficient evidence.13,32,33 Many clinicians prefer prescribing these
medications over hypnotics, because of perceived concerns regarding the risks of dependence and tolerance
associated with hypnotics, and despite antidepressants,
antipsychotics and antihistamines also having serious
side effects including weight gain, anticholinergic side
effects and diabetes. The decision to prescribe this group
of medications for insomnia should be based on a careful
risk–benefit analysis, not solely on concerns regarding
the risks associated with hypnotics.
Among herbal and alternative medication choices for
treating insomnia, valerian has the most evidence
showing possible mild improvements in sleep latency,
with inconsistent effects on the rest of the objective
sleep parameters.13 Although valerian shows some
promise in improving sleep latency without side effects,
the clinical trials are poorly designed and generally of
short duration.34
Conclusion
Insomnia is complex and usually chronic by the time the
individual consults a health practitioner, with cognitive,
behavioural and social factors involved in its maintenance. Simple instructions, such as avoiding stress, or
short-term use of hypnotics are usually not effective.
CBT-i is an effective intervention with long-term efficacy
that enables patients to better manage and live with their
insomnia symptoms. The development of online delivery
of CBT-i markedly improves access to treatment and can
be readily used in primary care as first-line treatment for
most patients, with specialised sleep services managing
more complex cases, those with ongoing symptoms and
those who require person-to-person care.
Competing interests: David Cunnington has received payment for consultancy work,
lectures and educational presentation development from BioCSL, and for lectures from
Servier and Bayer Healthcare. Antonio Fernando has received educational grants and/
or payment for lectures from BioCSL, Eli Lilly, MSD, Jannsen, Lundbeck and Sanofi.
Provenance: Commissioned by supplement editors; externally peer reviewed.
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