The Nature of Insomnia
Insomnia itself can be difficult to manage and live with it.
An initial complaint of insomnia may refer to a number of different things, such as;
- An inability to get to sleep.
- An inability to stay asleep.
- Waking too early.
- Unsatisfying sleep.
- Tiredness during the day, which individuals assume is caused by inadequate sleep the previous night.
A range of underlying physical conditions can contribute to sleep disturbances, such as coughs, itches, pain, restlessness, frequency or urination and breathlessness. These may lead to any of the above complaints, and they need diagnosis and proper treatment.
There is a particular condition that deserves special notice. This is obstructive sleep apnoea, a condition commonest in middle aged men who are somewhat overweight, but who in particular have large necks. In a serious form, it may affect up to 3% of men. It involves the airway collapsing on attempted inhalation, which typically happens when sleeping at night lying on the back. Collapse of the airway leads to the individual stopping breathing until the respiratory drive becomes so intense that the airway is forced open – usually with a loud snort. The effort is so intense that individuals usually have their sleep disturbed, leading to poor quality sleep and hence tiredness next day. The snort is so dramatic and loud that bed partners are often woken. The diagnosis is therefore commonly made by interviewing the sleeping partner who complains about snoring, and will usually have noticed that their partner often appears to stop breathing for anything from 10-60 seconds. The significance of this condition for our purposes is that, because there is poor sleep and fatigue next day, the individual may come seeking something to improve his sleep, but treatment with hypnotics may be fatal. The condition can be treated very successfully with a method called CPAP (continuous positive airways pressure), which involves wearing a specially constructed device while asleep.
There are two other notable but relatively rare conditions, which are partly physical and partly social – advanced sleep phase insomnia and delayed sleep phase insomnia. These conditions, which stem from the functioning of the circadian clock, arise in individuals who fall asleep too early in the evening and wake too early the next day (advanced sleep phase insomnia) or who fall asleep too late and then unable to get up (delayed sleep phase insomnia). Essentially, we all tend constitutionally to be either ‘larks’ (waking early and at our best early in the day) or ‘owls’ (at our best later in the day or in the evening). Advanced and delayed sleep phase disorders are exaggerations of these tendencies that may require specialist help to set right (1). In brief, the management of delayed sleep phase insomnia involves getting the individual to go to bed even later by 3-4 hours every night for 5-7 nights, until their sleep onset times have come all the way back to normal. The rationale behind this, as anyone who enjoys a sleep in at the weekend knows, is that it is easier for the clock to drift backwards rather than for it to be advanced. This behavioural strategy is more likely to be successful than any efforts to medicate the person to sleep at the correct time (1).
Table of Contents
The Parasomnias
Along with the primary disturbances, there are a group of disturbances called the parasomnias which involve disturbance of arousal / sleep maintenance mechanisms, leading to behaviours associated with (para) sleep. The most common parasomnias are the motor parasomnias, so-called because they involve movement. These include sleep walking, bruxism (tooth grinding), night terrors and restless legs syndrome. These different conditions run in families. The behaviours usually have their onset in association with the deeper strategies of non-REM (rapid-eye movement) sleep, and typically, therefore, start around 2 hours after the onset of sleep, unlike sleep apnoea which leads to disturbances immediately after falling asleep.
Restless leg syndrome may appear first as a distinctly unsettling pre-sleep impatience or twitchiness of the legs. This is a familial condition, which can be treated successfully with clonazepam.
Narcolepsy
As with the parasomnias, narcolepsy involves a disturbance of arousal mechanisms. But where the parasomnias involve the production of behaviour even in someone who is deeply asleep, narcolepsy is a matter of finding a sudden onset of sleep when the individual is wide awake. Starting usually around the age of 19-20, the primary feature of the condition involves falling asleep in company, but there may be other problems such as catalepsy, sleep paralysis and hypnagogic hallucinations.
Catalepsy involves episodes of what seems like a temporary paralysis of the mouth, limbs and sometimes even of the whole body. This can appear unprovoked but it is often triggered by strong emotion. If troublesome, this symptom may respond to an SSRI. Sleep paralysis refers to waking up to find oneself unable to move, or even to speak. The condition usually lasts only a few minutes but it may be sufficiently alarming to lead people to make a will out of fear of being mistakenly thought to be dead and ending up being buried alive. Finally individuals with narcolepsy may have intense visual or auditory hallucinations on falling asleep or waking up. These may sometimes lead to a referral to a psychiatrist with a query of whatever the condition may be an early schizophrenia.
The treatment of narcolepsy is with psychostimulants. The most commonly used drugs are pemoline, methylphenidate, dexamphetamine or the anti-parkinsonian drug, selegiline.
Psychological Causes of Insomnia
Aside from the transient causes of sleep disturbance, such as jet lag or shift work, or the physical causes of sleeplessness, a complaint of poor sleep most commonly stems from a psychological / psychiatric problem. Poor sleep leading to a perception of and complaint of insomnia may be
- Consequent on a shock.
- Part of an anxiety state.
- Occur spontaneously.
- Occur initially either spontaneously or after a shock, or as part of an anxiety state, but subsequently become a matter of habitual inability to get asleep properly and increasing frustration or anxiety at this inability.
- Occur as a symptom of depression.
Depression typically causes early morning wakening with an ability to fall asleep again. It may also cause repeated awakening during the night. The treatment in this case is an antidepressant as the usual benzodiazepine hypnotics may be relatively ineffective. Many clinicians would say that a majority of chronic sleep problems probably stem from an unrecognised depressive disorder, and that early morning wakening in particular should be taken as indicative of depression, until proven otherwise.
Insomnia
The proper management of a complaint of insomnia will eliminate any possible physical causes of poor sleep, as well as recognise and treat any depressive disorder or acute anxiety state. But there will still be a group of individuals left who complain of poor sleep, and probably of having had poor sleep for years. This is a group who are particularly likely to expect drug treatment to solve their problems, but the role of pharmacotherapy here is as uncertain as it is in the management of anxiety states such as hypochondriasis.
The great problem is that current evidence suggests that many people in this group have sleep that is no worse than that of the rest of the population (2, 3). Often complainers are slightly older, in which case the complaint will be justified to the extent that sleep depth does decline with age and naps during the day may lead to less than the former 6-8 hours sleep at night. But the problem remains in that others who are ageing do not complain.
In the non-complaining population there are individuals, who for no apparent reason, at some point during their lives, find themselves unable to sleep or able to get by on 2-3 hours only. This may be highly distressing as they are left wandering around a house while everyone else is sleeping peacefully. Often the only remedial treatment that can be undertaken in such cases is to minimise the frustration that the problem causes, for example, by finding something constructive to do.
In the case of complainers, the problem in many respects seems similar to health anxiety (hypochondriasis – see occasions of anxiety), with a specific focus on sleep. As in health anxiety, individuals become concerned about a symptom, which is made worse by noticing it. The problem may start during a period of stress, which in its own right will cause sleep quality to fall off. All of us faced with stress have a tendency to focus away from the cause and on to something else – this is called displacement. Focusing on to sleep (or stomach problems for instance) means that individuals end up thinking or feeling that everything would be okay, if only their sleep (or their bowels) were okay. This is likely to become a chronic rather than just passing problem, especially if there is either an individual or a family history of sleep problems, or very fixed ideas about sleep.
Unhelpful ideas about sleep may include the idea that it is necessary to get 8 hours sleep a night or else health will suffer. This is similar to the idea that it is necessary to have a bowel motion every day. Temporary constipation is clearly going to be far more worrying to people who have fixed ideas about regular bowel motions, and such ideas in turn are more likely in someone who comes from a home where there were such ideas, or where there were bowel problems of one sort or another.
Another unhelpful idea is the notion that sleep is something that I should be able to control. There is a paradox here in that we all to some extent have the illusion that we control our sleep. When it is disrupted, if attempts to sort the problem out are seen in terms of re-exerting control, they are all too likely to fail.
Studies (2, 3) suggest that the complaint of some insomnia may cover a number of different conditions.
- For some people, the primary concern is with the after-effects of poor sleep on how they are likely to concentrate and operate in general the next day.
- For others, the concern is with the problem of falling asleep – these have a performance anxiety, as it were, where sleep is concerned.
- Yet others have a problem which seems to be one of finding their mind more active just as soon as their head hits the pillow and this activity then interferes with sleep.
- A fourth group have difficulties staying asleep. They find they wake up, and are bothered by doing so in a way that others of us are not, in a way that interferes with being able to get back to sleep – we all awake more often during the night than we suspect but it seems we are, in the main, unaware of such episodes.
- Finally, there is also a group who are simply dissatisfied with the quality of their sleep.
These groups are important to distinguish as the treatment for each group differs.
There is one further problem that needs monitoring, which is the question of perception. Individuals with sleep problems appear to overestimate the amount of time it takes them to fall asleep and the frequency with which they wake up during the night. This perceptual difficulty may in fact be made worse by hypnotics (4). It seems that individuals on sleeping pills underestimate the time it takes them to fall asleep and have an amnesia for their awakenings during the night. This of course only compounds the problem of how adequate or inadequate sleep is perceived to be on withdrawal of sleeping pills. On withdrawal, there appears to a gross overestimate of how long it takes to fall asleep and a hyper-awareness of any wakenings that occur during the night.
References
- Waterhouse JM, Minors DS, Waterhouse ME: Your body clock: how to live with it, not against it: Oxford: Oxford University Press; 1990.
- Coyle K, Watts FN: The factorial structure of sleep dissatisfaction. Behav Res Ther, 1991, 29:513-520.
- Espie C: The psychological treatment of insomnia. Chichester: John Wiley and Sons; 1991.
- Schneider, Helmert D: Why low dose benzodiazepine-dependent insomniacs can’t escape their sleeping pills. Acta Psychiatr Scand 1988, 78:706-711.
