Study Why depression is associated with permanent stress

New stress-causing mechanisms discovered in depression

When sufferers suffer from depression, they also increase their brain area, which is responsible for stress control. As a result, the increased level of the stress hormone cortisol resulting in permanent tension could often suffer from the depressive. These findings come from a German research team from the Max Planck Institute.

Researchers from the Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) in Leipzig and the Leipzig University Hospital have recently discovered in an investigation that patients with affective disorder have an average of five percent loss on the left side of the hypothalamic brain region is enlarged. The scientists see this as the reason why people with depression are more exposed to stress. The study results were recently published in the journal "Acta Psychiatrica Scandinavica".

People with depression often feel stressed and tense, though there is no obvious reason. Researchers at the Max Planck Institute have now discovered that enlargement in the hypothalamic brain region could be responsible for the increased stress hormones. (Image: hikrcn / fotolia.com)

Widespread depression

Depression is one of the most common mental illnesses worldwide. The World Health Organization (WHO) states that in 2015, around 322 million people were affected by the mental illness. This corresponds to 4.4 percent of the world population. Despite the frequent occurrence, the exact causes of depression are still unclear.

The search for the triggers

As the MPI researchers report, past research has increasingly come to the realization that the disease is probably caused by a combination of genetic predisposition and stressors from the environment. It is already known that in people with a higher genetic predisposition to depression, the body's stress system does not work properly.

How the stress system works in the body

The stress system is referred to as the hypothalamic-pituitary-adrenocortical axis (HPA axis). This is usually activated when we are in a stressful situation, such as a dangerous situation or a challenge that requires more energy from the body. The HPA axis ensures an increased release of the stress hormone cortisol, which provides a short-term increase in performance. Afterwards, the HPA axis normally ensures that the payout is reduced again.

How the stress system reacts to depressives

"But in people with depression or an increased risk of this is not the case," write the MPI scientists in a press release on the study results. Here, the feedback mechanism does not work. The stress system would remain in the high performance mode, although there is no apparent stress situation.

In depressed individuals, the hypothalamus is enlarged

"We have observed that this brain region is enlarged in both people with depression and bipolar disorder," reports Stephanie Schindler, the lead author of the study. Both are forms of an affective disorder. The researchers were able to prove in 84 subjects that in people with an affective disorder, the left hypothalamus by an average of five percent greater than in healthy people.

The heavier the disease the bigger the brain area

In addition, the researchers were able to show that the brain region, which is about the size of a one-cent piece, is greater, the more severe the affective disorders are. Furthermore, the MPI scientists were able to document that medication with antidepressants did not affect the size of the hypothalamus.

Ambiguities despite new findings

"We do not yet know what role the larger hypothalamus plays in depression or bipolar disorder," summarizes Stefan Geyer, one of the study leaders. Scientists believe that the increased activity of the hypothalamus may induce plastic changes, resulting in greater volume. (Vb)