Insomnia, chronic pain and depression are common disorders and a lot of people are likely to experience one or more of these during their lifetime. In this article, I will explain why these three disorders tend to occur within the same people, and how having one of them may lead to an increased risk of getting one or both of the other disorders. Finally, I will discuss why this is important to be aware of.
A vicious circle
A very important fact that a lot of people and even medical professionals do not consider very often is that having either depression, insomnia or chronic pain increases the risk of also experiencing the other disorders [1, 2]. For example, a Norwegian study found that about half of all people with chronic pain suffer from insomnia . Also, most of the people who have a clinical depression (over 50%) experience sleep disturbances .
In addition to increasing the risk of other disorders, it has been found that people feel worse (have more severe symptoms) when they also have other disorders. For example, the experience of pain has been found to be is worse for people who experience little or low quality sleep , and depressive symptoms have been found to be worse among pain patients who sleep poorly, compared to those with normal sleep patterns . Patients with multiple disorders are therefore likely to be experiencing a very poor quality of life and to suffer tremendously.
What causes the vicious circles?
There are several potentially complimentary explanations for why insomnia, depression and chronic pain tend to appear in the same individuals. The first explanation is simple, and suggests that having one type of disorder increases the likelihood of developing other disorders. For example, it is quite plausible that individuals who experience chronic pain or depression may eventually also develop sleeping problems because the pain is making it difficult to relax. Similarly, it is also plausible that people who experience sleeping difficulties may develop a negative mood simply because they are tired and they find it difficult to solve everyday challenges when they are not rested. Consequently, a vicious circle of experiencing increasing levels of ill health, and multiple disorders may arise from simply having one single untreated disorder.
A common cause
A slightly more complicated explanation is that insomnia, chronic pain and depression may have a common underlying cause. Several researchers have proposed this idea, and suggests that stress could be one of the factors which could trigger both pain, depression and insomnia [1, 2]. We know that stress is related to the type of brain chemistry (dopamine regulation) which is important for whether we feel sleepy or awake, cheerful or sad, and it is also related to how well we tolerate pain. According to this hypothesis of a common cause, we are likely to become more susceptible for developing insomnia, depression or chronic pain, if we experience severe stress over longer periods of time. The vicious circle may therefore escalate because experiencing stress, which could lead to sleeplessness, or other symptoms, which in turn could further increase the experience of stress, which finally could lead to the development of severe disorders, which then could lead to vulnerability for other disorders. It is important to note that high stress levels is likely to influence health only to the extent to which it lasts for a relatively long period of time. Common stressful experiences could be many different things, such as: being bullied at work, high levels of conflict in personal relationships, or simply having many obligations and not enough time.
Why is this important?
The knowledge of how insomnia, depression and chronic pain interact is important for people because it is very common to treat our physical and mental problems as separate and independent problems. A very practical and important problem related to this, is that many people feel ashamed of being depressed, and are therefore less likely to seek help. There are also studies which have shown that depressed people who also have pain, are less likely to seek help for their depression, than those who only have depression. In fact, people with both pain and depression are more likely to seek help for their pain only, and this is likely to lead to many cases of untreated depression [6, 7]. As we have learned, untreated disorders are likely to experience more stress, worse symptoms of pain and increased risk of insomnia. Untreated symptoms or disorders are therefore likely to contribute to the vicious circle where health and quality of life gradually becomes worse over time.
What to do?
There is no easy fix for this problem, but it appears that there are two important measures that can and should be taken to avoid that more people are caught up on the vicious circles of depression, chronic pain and insomnia. The first is to try to prevent long term stress, and the second one is to make it easy and accessible for people to report and receive help for their health complaints. It appears to be particularly important to make it easy to seek help for mental health problems, as these often are underreported, and therefore remain untreated. While these are very complicated problems to solve on a large scale, we can all put this new knowledge to use by being more aware of the vicious circles in our own lives and when looking after our family, friends and colleagues.
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