Depression is one of the most common mental diseases worldwide. It affects up to 16% of the population worldwide. At present, up to 3.1 million people in Germany alone suffer from depression requiring treatment; that is up to 10% of all GP patients. However, only less than 50% ultimately consult a doctor. But what are the causes of such an important and frequent disease?
Causes
Depression is usually caused by the interaction of many different factors, it is multifactorial, so to speak. The role played by genetic (hereditary) and environmental factors often varies from individual to individual. There are people who survive high emotional stress and crises with ease after a short time, and there are people who fall into a deep hole after losing their job or being separated; who withdraw more and more, who isolate themselves from the world and ultimately think about suicide.
These affected persons are often – in comparison to “healthy” people – more sensitive to mental stress, i.e. they often have to endure and process life events that shake their tolerance. This vulnerability (= increased sensitivity) plays an important role in the development and maintenance of depression. In summary, it can be said that the basis for the development of depression is ultimately based on genetic factors and a formative life event, such as the death of a close person.
Genetic predisposition
Both twin studies and studies with families show that genetic factors are important in depression. A hereditary predisposition plays a major role in the development of depression. Studies have shown that in more than 50% of those affected, at least one parent was depressed.
In other words, if one parent is ill, the risk of developing depression is as high as 15%. In the case of identical twins, the risk that both will develop depression is up to 65%. This shows that hereditary factors play an important role in the development of depression. However, a hereditary predisposition alone does not necessarily mean that one must also suffer from depression. Ultimately, environmental factors – whether shocking events occur or not, or how well, for example, someone learns to deal with difficult situations – play an important role.
Metabolic disorders
Many studies show that depression in particular is often characterized by changes in the neurotransmitter balance. Neurotransmitters are messenger substances that trigger certain reactions in the body such as pain or anxiety. and The role of serotonin/neurotransmitters in depression In a depression, neurotransmitters such as serotonin, noradrenalin and dopamine in particular lose their balance.
Changes can also occur at their receptors (docking sites where messenger substances can act). For example, they can become less sensitive to their messengers, which in turn leads to a weakened effect of the neurotransmitters. It is assumed that the reduced serotonin and noradrenalin concentrations lead to a depressed mood and lack of drive. Today, this deficiency can be compensated and stabilised by special medication (“antidepressants”).
All articles in this series:
