Describe and evaluate explanations of insomnia

Short term insomnia is where some people suffer difficulties in sleeping for a short period of time, and example is days or a few weeks. Short term insomnia tends to be caused by immediate worries, such as an exam or a death in the family, noises at night, jet lag or a temporary medical condition, such as a cold.

Long term insomnia which is known as chronic insomnia describes sleep difficulties lasting more than four weeks. A distinction is then made between secondary and primary insomnia. Secondary insomnia is much more common.

Primary insomnia occurs when a person is having sleep problems that are not directly associated with any other health condition or physical cause such as drug abuse or medications. A person may be feeling stressed or depressed but such psychological states that are not the cause of the insomnia. It may be that the individual has developed bad sleep habits and this causes insomnia, but insomnia is the only problem. Sometimes insomnia may have had a identifiable cause but this has disappeared, yet the insomnia persists because of an exception of sleep difficulty - in their own words, the individual has come to expect that they will have sleep difficulties and these expectations lead to anxiety which then continue to cause insomnia.

Secondary insomnia is when a person is having sleep problems because of something else. There is a single, underlying medical, psychiatric or environmental cause. In such cases insomnia is a symptom of the main disorder, i.e. it comes second, after the main disorder.

It is important to distinguish between primary and secondary insomnia because of the implications for treatment. If insomnia is a symptom of another disorder then it is important to treat the disorder rather then the insomnia. So, for example, if insomnia is the result of chronic depression it would be unhelpful to simply treat the symptom. However, it may not be that simple to work out the cause of a person’s insomnia - does depression cause insomnia or does insomnia cause depression? A study of almost 15,000 Europeans found that insomnia more often preceded rather than followed cases of mood disorders, such as depression. This means that, in some cases, it might be helpful to read insomnia regardless of whether it is a primary or secondary effect.

The importance of understanding and being able to find ways to deal with insomnia is shown in the potentially serious, and even fatal, consequences of the disorder. Cognitive impairment may also be a consequence, for example memory loss and poor concentration during the day. Zammit et al found that patients with insomnia scored lower on the Medical Outcomes Study Cognitive Scale than control participants, demonstrating problems with concentration, memory, reasoning and problem solving.

Sleeping and cognitive difficulties obviously create a risk for safe driving. One study compared the performance of adults who had been deprived of one nights sleep with adults given alcohol. They found that even keeping people awake for three more hours than usual led to impairments equivalent to modest levels of alcohol. They found that even keeping people awake for three more hours than usual led to impairment equivalent to modest levels of alcohol. The National Traffic Safety Administration estimates that 1500 deaths annually are related to sleepiness/fatigue. The effects of tiredness have also been linked to industrial accidents as a result of shit work.

As discussed above it is also possible that insomnia is actually a cause of psychological problems, such as depression and anxiety disorders, rather than an effect. Breslau et al found that insomnia was also associated with increased risks for drug and alcohol abuse.

A Canadian study found fewer immune cells in the bodies of people with chronic insomnia compared with good sleepers. This would make insomniacs more vulnerable to physical illness. However, here again there is a problem with cause and effect because it could be that stress was the initial cause of insomnia.

Spielman and Glovinsky propose a useful distinction between predisposing, precipitating and perpetuating components in their 3P model of insomnia.

Predisposing factors include a genetic vulnerability for insomnia. Evidence for a genetic link comes from twin studies. For example, in one study Watson et al found that 50% of the variance in the risks for insomnia could be attributed to genetic factors. Research also suggests that psychological factors may be attributed ti genetic factors. Research also suggests that physiological factors may predispose a person to develop insomnia. For example, it has been found that insomniacs are more likely to experience hyperarousal (high physical arousal) both when awake and asleep. Hyperarousal would make it more difficult to get sleep. Such factors explain why only some people develop insomnia, for example in response to stress or jet lag.

Precipitating factors are the events that trigger the disorder in a vulnerable individual. Two individuals may experience the same stressors but only one develops insomnia as a consequence because of predisposing factors. Environment triggers for insomnia include stress at work, exams and shit work.

Perpetuating factors are also important, i.e factors that maintain insomnia when the original causes have disappeared or been treated. Perpetuating factors include being tense when going to bed because of previous sleep problems. Essie suggests that such perpetuating factors are key to chronic insomnia.