What you need to know about insomnia
Sleep consultant Dr Irshaad Ebrahim answers GP Dr Sabby Kant’s questions on underlying causes, diagnostic criteria and treatment with medication, behavioural therapy and herbal remedies
Sleep consultant Dr Irshaad Ebrahim answers GP Dr Sabby Kant's questions on underlying causes, diagnostic criteria and treatment with medication, behavioural therapy and herbal remedies
1 Can you define insomnia and outline the different types?
It can be classified according to cause:
• Primary insomnia is insomnia that occurs when no comorbidity is identified. Commonly, the person has conditioned or learned sleep difficulties, with or without heightened arousal in bed. Typically, primary insomnia lasts about a month but accounts for about 15 to 20% of long-term insomnia.
• Comorbid (or secondary) insomnia is when insomnia occurs as a symptom of, or is associated with, other conditions, including medical or psychiatric illness, or drug or substance misuse.
Insomnia can also categorised according to duration. Although there are various definitions of duration in the literature for the purpose of this topic, insomnia is categorised as:
• short-term (acute insomnia) if insomnia lasts between one and four weeks
• long-term (or persistent or chronic) if insomnia lasts for four weeks or longer.
2 What are the key underlying causes and factors for chronic insomnia? Specifically, can you list the really important non-obvious ones?
In terms of primary insomnia:
• Idiopathic insomnia starts early in life and has a persistent, unremitting course.
• Psychosocial insomnia is due to a conditioned response in which the person associates the sleeping environment with heightened arousal. It often starts in response to a stressful event but continues after the event has been resolved.
There are a huge range of factors that can cause secondary insomnia, including:
• psychosocial stressors, which usually cause short-term sleep problems – such as occupational, personal, financial, academic or medical problems, for example
• environmental stress such as noise, or the death or illness of a loved one
• psychiatric comorbidities such as mood disorders (depression, bipolar disorder and dysthymia), anxiety disorders and psychotic disorders.
Major medical comorbidities include:
• cardiovascular: angina, congestive heart failure
• respiratory: COPD, asthma
• neurological: Alzheimer's disease, Parkinson's
• thyroid dysfunction
• rheumatological: fibromyalgia, chronic fatigue syndrome, osteoarthritis, rheumatoid arthritis
• gastrointestinal: gastroesophageal reflux disease, irritable bowel syndrome
• genitourinary: incontinence, benign prostatic hypertrophy, nocturia
• sleep disorders: restless legs syndrome, sleep apnoea, periodic limb movement disorder, circadian rhythm disorders
• chronic pain.
But always remember that prescribed or over-the-counter medications need to be borne in mind as possible causes of insomnia. These include antidepressants (SSRIs, venlafaxine, bupropion, duloxetine and monoamine oxidase inhibitors), the antiepileptics lamotrigine and phenytoin, ß-blockers and calcium channel blockers, NSAIDs, steroids and thyroid hormones, and the sympathomimetics salbutamol, salmeterol, theophylline and pseudoephedrine. Stimulants such as methylphenidate and modafinil can obviously cause problems as can alcohol, recreational drugs, caffeine and nicotine.
3 What diagnostic criteria are helpful in primary care? What's the most useful way to take a sleep history in primary care? Are there any sleep diary templates we could give patients and how do you interpret them?
It's important to explore the patient's beliefs about sleep and what they regard as normal sleep.
Ask about how they function during the day – if there's no impairment they may simply have a reduced need for sleep or an unrealistic expectation of sleep. Ask about the impact it has on their quality of life, ability to drive, employment, relationships and mood.
Ask about recent stressors such as grief, situational stress, illness, mental health problems and occupational factors. If you identify a stressor further evaluation is not usually necessary.
Then determine whether there is an underlying cause of insomnia or an associated comorbid condition. Take a detailed history and, if indicated, any investigations to identify any coexisting physical conditions.
Excessive daytime sleepiness – rather than fatigue or tiredness – may indicate a primary sleep disorder such as obstructive sleep apnoea syndrome. The Epworth Sleepiness Scale (ESS) is invaluable in determining pathological daytime sleepiness.
Take a drug history, including prescription drugs, recreational drugs, caffeine, nicotine and alcohol.
Take a sleep history from the person and – if possible – their partner or caregiver. This should include sleep and wakefulness patterns (including daytime napping) and frequency of symptoms.
Determine the duration of symptoms and the likelihood of their continuing.
Consider asking the person to keep a sleep diary – the American Academy of Sleep Medicine has developed a useful two-week diary that can be downloaded from the link on the right.
4 Are there any useful criteria for what constitutes a ‘normal' sleep pattern?
Patterns of sleep vary with age; the number of awakenings increases and the total sleep time decreases with increasing age, probably because of physiological changes.
A meta-analysis of studies examining normal age-related sleep trends showed a wide variation with age. The average amount of sleep for each age category is given in the table (left)
5 What are best non-pharmacological interventions we can offer the chronic insomniac? We're often told about good ‘sleep hygiene', but what is the best way to get this advice across to patients who, by the time we see them, are often exhausted and convinced they need a prescription?
Sleep hygiene aims to make people more aware of the behavioural, environmental, and temporal factors that may be detrimental or beneficial to sleep.
Advise the person to:
• Establish fixed times for going to bed and waking up – and avoid sleeping in after a poor night's sleep.
• Try to relax before going to bed.
• Maintain a comfortable sleeping environment: not too hot, cold, noisy or bright.
• Avoid napping during the day.
• Avoid caffeine, nicotine, and alcohol within six hours of going to bed.
• Consider complete elimination of caffeine from the diet.
• Avoid exercise within four hours of bedtime – although exercise earlier in the day is beneficial.
• Avoid eating a heavy meal late at night.
• Avoid watching or checking the clock throughout the night.
• Reserve use of the bedroom for sleep and sexual activity.
As for other non-pharmacological treatments, there is no good evidence for the use of complementary therapies – for example, acupuncture, acupressure or herbal remedies such as valerian.
6 What is the role of behavioural therapies – such as CBT, relaxation techniques and so on – and how effective are they?
The following interventions all have evidence backing their use for the treatment of insomnia.
Stimulus-control therapy aims to help the person to re-associate the bed and bedroom with sleep, and to re-establish a consistent sleep-wake pattern.
Sleep restriction therapy involves limiting the amount of time spent in bed to the actual amount of time spent asleep, creating a mild sleep deprivation, and then increasing sleep time as the efficiency of sleep improves.
Relaxation training aims at reducing tension (for example, using progressive muscle relaxation) or minimising intrusive thoughts that may interfere with sleep.
Paradoxical intention involves staying passively awake, avoiding any intention to fall asleep. Its use is limited to people who have trouble getting to sleep – but not maintaining sleep.
Biofeedback provides visual or auditory feedback to help the person control certain physiologic parameters, such as muscle tension.
Cognitive therapy aims to examine and change the person's beliefs and attitudes about insomnia. It is frequently used in combination with a behavioural intervention – such as stimulus control, sleep restriction or relaxation training.
Although it's true that in most clinical trials, cognitive and behavioural interventions have been delivered by psychologists, there is emerging evidence that they can be successfully delivered by appropriately trained community nurses, primary care counsellors and GPs.
7 What is the role of pharmacotherapy? What's the most effective way to use anxiolytics and night sedation? What's not recommended? More specifically, are there any real clinical differences between zaleplon, zolpidem and zopiclone?
If functioning during the daytime is severely impaired, consider a short course of a hypnotic drug.
Hypnotics that are recommended for the treatment of insomnia are:
• Short-acting benzodiazepines — temazepam, loprazolam, lormetazepam.
• Non-benzodiazepines (the ‘z-drugs') — zopiclone, zolpidem and zaleplon (all are short-acting).
Diazepam is not recommended, but it can be useful if insomnia is associated with daytime anxiety.
If there has been no response to one hypnotic, do not prescribe another. But if the patient experiences adverse effects related to a particular hypnotic, consider switching to another hypnotic.
Use the lowest effective dose for the shortest period possible. The exact duration will depend on the underlying cause, but treatment should not continue for longer than two weeks.
Make sure the patient is aware that further prescriptions for hypnotics will not usually be given, ensure that the reasons for this are understood and document this in the notes.
Review after two weeks and consider referral for CBT if symptoms persist – see question 6.
Sedative drugs other than hypnotics – like antidepressants, antihistamines, choral hydrate, clomethiazole and barbiturates – are not recommended.
Current NICE guidelines state that, in terms of efficacy and clinical profiles, there is little evidence to distinguish between zaleplon, zolpidem, zopiclone or the shorter-acting benzodiazepine hypnotics.
8 Have you any advice on helping patients stop using pharmacotherapy? Is tapered withdrawal a useful strategy?
Tapered withdrawal should be part of a comprehensive programme of treatment that includes at its core a CBT approach.
Patients with insomnia who have been using medication for extended periods tend to be anxious about coming off the medication and without providing the support through a sleep CBT programme the likelihood of relapse is high. Unfortunately such programmes do not exist in the NHS presently but are offered in private centres like the ones I practise in and we are able to provide this service to PCTs after approval by exceptional treatment panels.
9 I often see patients who have tried over-the-counter medications such as Nytol. Could you describe the over-the-counter remedies available – including herbal and complementary ones – and comment on their effectiveness and safety?
The role of over-the-counter medication is generally to treat short-term situational insomnia – if a patient has tried these with no success then a more comprehensive treatment approach is needed. This could mean a referral to a local sleep clinic that provides medical and psychological treatment for patients with insomnia.
10 Sufferers often express an interest in treatment with melatonin. How effective is it and what's your opinion as to where it fits in? There is now a prescribable form – is it appropriate for us to use this in primary care and of so in which patients?
Melatonin is important in controlling the circadian rhythm and can shift the timing of sleep-wake cycles. So it follows that where sleep difficulties are due to circadian desynchronisation - for example in jet-lag – melatonin may help.
In the US melatonin is classified as a dietary supplement and is not subject to Food and Drug Administration regulations and it is freely available over the counter. But last year a prolonged-release melatonin tablet called Circadin was licensed in the UK for the short-term treatment of primary insomnia among adults aged 55 and over.
A full list of cautions, contraindications and interactions for this product can be found in the BNF.
There have been two placebo-controlled trials of modified-release melatonin in the dose and indication licensed in the UK. Both had similar study designs – patients with primary insomnia for at least one month, with no underlying cause, randomised to receive Circadin or placebo for three weeks, taken once a day, one to two hours before bedtime.
The quality of sleep was significantly improved with melatonin compared to placebo in both studies, but the clinical significance of both rating scale increases in the studies is not clear.
I am not aware of any studies comparing modified-release melatonin with hypnotics.
From the current evidence I would not recommend melatonin for the treatment of short-term insomnia.
Dr Irshaad Ebrahim is medical director at The London Sleep Centre . The centre and its sister clinic
The centre and its sister clinicThe Edinburgh Sleep Centre offer diagnostic and treatment services for people with sleep disorders and related medical and psychological disorders.
Dr Sabby Kant considers the responses to his questions
The author takes a much-needed logical approach to this common problem in primary care. It is useful to reassure patients with
primary insomnia (where there is an identifiable comorbidity) that it typically lasts only a month. For secondary insomnia it seems a barrel-load of factors can be causal or contributory – including drugs, with some unusual suspects such as calcium antagonists and NSAIDs.
A useful tip when taking a sleep history is to ask the patient how they function during the day and their wakefulness patterns. GPs will find it useful to be aware of circadian rhythm sleep disorders where total sleep time is normal but timing is out of synchrony.
It is also of practical value to know the average sleep required by age category – for example, those over 80 years require on average only 5.8 hours per night.
Dr Sabby Kant is a GP in Hillingdon, Middlesex