A review of GP interventions for insomnia
Classifying insomnia as chronic or short term isn’t useful, says Professor Kevin Morgan, in this review of traditional and new interventions
Classifying insomnia as chronic or short term isn't useful, says Professor Kevin Morgan, in this review of traditional and new interventions
Insomnia is the most frequently reported psychological symptom in the UK and a significant cause of impaired personal, social, and occupational functioning.
Persistent insomnia also delays recovery and rehabilitation after acute illnesses, increases older patients' risk of falling, and is an independent risk factor for major depression.
The personal and public health benefits of effective insomnia treatment are substantial, and achieving them in primary care is not unrealistic.
What is insomnia?
Insomnia is characterised by a complaint of difficulty initiating or maintaining sleep, or of non-restorative sleep, despite adequate opportunities to sleep. These difficulties occur three or more times a week, persist for at least a month, and are associated with impaired daytime functioning.
Most people with insomnia report daytime fatigue, but only about 25% report symptoms of daytime sleepiness. Other daytime symptoms include mood disturbances and impaired concentration.
Defined in this way, all insomnias may be regarded as ‘chronic' in the sense that their histories equal or exceed one month's duration. Without being able to see into the future, attempting to categorise a sleep disturbance as ‘short-term insomnia' is both unnecessary – since by definition it will improve on its own – and unwise – since it may yet meet criteria for chronic insomnia.
How much sleep do we need?
Duration is not the only parameter along which sleep can vary. Latency, depth and continuity also matter. But it is duration that patients often focus on.
One of the most important determinants of sleep duration is age, with normal sleep becoming shorter, lighter and more fragmented as we grow older. A healthy 60-year-old may sleep at least an hour less per night than 30 years earlier.
So any assumption that ‘ideal' sleep duration can be represented by a single value – say eight hours – throughout adulthood is unhelpful. Added to this are the substantial differences found in subjective sleep times between individuals at any age. Some 90% of the adult population report six to nine hours of sleep per night, with an average of seven.
So how much sleep do we need? Simply put, enough to deliver you refreshed and able to function efficiently throughout the next day. At any point in their lives, most individuals know how much sleep they require. And it is interesting to note that, on functional, physiological and statistical grounds, this value is unlikely to be eight hours.
What causes chronic insomnia?
In a strict aetiological sense, answering this question may deliver little of clinical value. How, for example, can a historical cause inform treatment of a 75-year-old woman who says her insomnia began after the birth of her first child 50 years earlier?
A more useful approach is to assume that chronic insomnia reflects contributions from three sources:
• predisposing factors
• precipitating factors
• perpetuating factors.
Predisposing factors collectively represent an inherent vulnerability to or, in epidemiological terms, risk factors. Common predisposing factors include higher levels of trait anxiety, susceptibility to cognitive intrusions, and a capacity for selective attention.
Precipitating factors are events that provoke or trigger an insomnia episode against a background of vulnerability, for example, the birth of a child.
Perpetuating factors are counterproductive behavioural responses to sleep disturbance, which, over time, help to maintain insomnia as a chronic problem, sometimes long after the precipitating factors cease to be active. Typical perpetuating factors include:
• extending the time spent in bed – on average, people with insomnia spend much longer in bed than people without insomnia
• daytime napping to compensate for poor quality sleep
• the progressive loss of conditioned cues for sleep in bed as the bedroom becomes increasingly associated with wakefulness and frustration.
Approaching insomnia in this way helps to explain why some precipitating events such as acute illnesses, sports injuries, occupational stresses, childbirth and bereavement can disturb sleep in most of us, but produce chronic insomnia in only the predisposed minority.
Research also suggests a similar process in human ageing, where the experience of reduced sleep duration, depth and continuity is universal, but only a minority of those over, say, 65, report insomnia. Epidemiology suggests an insomnia prevalence of 25-30% in this age group.
Insomnia and comorbidity
Until recently most diagnostic systems divided insomnias into primary – occurring in the absence of physical or psychological disorders and secondary – resulting from physical or psychological disorders.
However, the assumption that treating secondary sleep symptoms is unlikely to be successful unless the primary condition is resolved does not stand up to research scrutiny. Similarly, because of perpetuating factors, addressing presumed ‘primary' causes may not resolve the insomnia.
For practical purposes, therefore, ‘comorbid' insomnias – now the preferred term – can often be treated as primary.
Sleep problems can be usefully assessed using daily sleep diaries, where patients record bedtimes, wake times, hours slept, and sleep quality each morning.
Self-monitoring via sleep diaries can be associated with symptom improvements.
Sleep diaries also provide an invaluable insight into the patient's sleeping habits and, if continued during therapy, are a useful index of treatment outcome.
In its review of newer hypnotics NICE recommended that hypnotic drug therapy should be considered only ‘after due consideration of the use of non-pharmacological measures'.
Two evidence-based non-pharmacological approaches have been evaluated in primary care: sleep hygiene and cognitive behaviour therapy.
Sleep hygiene, a prescriptive list of lifestyle dos and don'ts, has proved effective in preventing insomnia from worsening, and in facilitating the benefits of CBT and hypnotic therapy. It provides a useful first step in treatment, and sends the important message that behaviour and lifestyle choices can influence sleep quality. (For suggested advice, see the box.)
CBT for insomnia (typically including sleep restriction, stimulus control and cognitive therapy) produces lasting improvements in sleep quality in 70-80% of treated patients. Recently completed randomised controlled trials have also shown that such approaches work effectively in primary care, and are effective among older patients, cancer patients, those with substantial comorbidity, and long-term hypnotic users1,2.
CBT for insomnia primarily addresses the perpetuating factors by:
• accelerating sleep onset using cognitive therapy to control intrusive and ruminative thoughts
• amplifying the experience of sleepiness in bed using sleep restriction
• substantially reducing the amount of time spent awake in bed, using stimulus control procedures that oblige patients to leave the bed and bedroom if they are not asleep after 15 to 20 minutes, and only returning to bed when they are sleepy.
Effective CBT for insomnia need not be delivered as a stand-alone primary care service. The skills can be learned by a range of healthcare professionals in primary care who can use these skills in routine practice. Successful trials in the NHS have involved health visitors, practice counsellors, psychologists and practice nurses.
What about hypnotics?
The optimal treatment of insomnia should combine all available evidence-based treatments in a broad, flexible response to patient need. This response must include, but need not be dominated by, hypnotic drugs.
Hypnotic drugs have proved effective and safe in the management of short-term sleep disturbances when prescribed within their licence, with an agreed exit strategy, and for conditions that do not result from recreational, occupational or lifestyle abuses of sleep mechanisms. But their value in the longer-term management of insomnia is doubtful.
Extensive systematic reviews of chronic insomnia management have concluded that the clinical benefits of benzodiazepine agonists are almost certainly inflated by reporting bias, and need to be offset against the evidence that these drugs pose a significant risk of harm. Among elderly patients, however, the modest benefits of hypnotics appear to be outweighed by the risk of harm3,4.
It remains the case that most long-term users of hypnotics have sleep profiles indistinguishable from those who have untreated chronic insomnia.
Professor Kevin Morgan is director of the Clinical Sleep Research Unit at the Sleep Research Centre, Loughborough University
Competing interests None declared
Typical sleep hygiene advice for patients Typical sleep hygiene advice for patients
• Products containing caffeine (tea, coffee, chocolate, soft drinks) should be discontinued at least four hours before bedtime. Caffeine is a stimulant, and can keep you awake.
• Avoid nicotine (including nicotine patches or chewing gum) an hour before bedtime and when waking at night. Nicotine is also a stimulant.
• Avoid alcohol around bedtime because although it can help induce sleep, it can disrupt sleep later in
• Avoid eating a large meal just before bedtime, although a light snack may be beneficial.
• Try to do regular physical exercise if you are able, but avoid doing this in the two hours preceding bedtime.
• Keep the bedroom calm and tidy. Select a mattress, sheets and pillows that are comfortable.
• Avoid extreme temperatures in the bedroom.
• Keep the bedroom quiet and darkened.