Depression causes permanent biological impairments in the brain

How long-term depression affects the brain?

Researchers have now found that untreated depression causes lasting biological changes in the brain. If depression is not treated in time, it leads to increased inflammation of the brain.

Researchers at the University of Toronto found that years of untreated depression caused a significant increase in inflammation in the brain. The experts published the results of their study in the English-language journal "The Lancet Psychiatry".

Depression does not just have immediate effects

In today's performance society more and more people suffer from depression. If these are not treated in time, they can lead to changes in the brain and thereby increase the likelihood of inflammation, say the authors. This shows that depression is not just a biological disorder with immediate effects. Over time, depression changes the brain in ways that require other forms of treatment that are not yet available, the doctors add.

Study had 80 participants

This was a relatively small study with only 80 participants. Twenty-five subjects suffered from untreated depression for a period of more than ten years. 30 participants were never diagnosed with depression. All participants were screened with so-called positron emission tomography scans (PET scans) to locate a specific type of protein resulting from the brain's inflammatory response to injury or disease.

Inflammation can protect the body

The right amount of inflammation throughout the body, including the brain, protects against disease and helps the body heal injuries, the researchers explain. However, too many inflammations lead to chronic diseases, including heart disease and possibly neurodegenerative diseases such as Alzheimer's and Parkinson's, say the experts.

Where do most inflammations occur??

Assuming that long-term depression leads to more inflammation, the researchers expect their study to find more protein in the brain of those who have suffered the most from untreated depression. And this assumption was finally confirmed. Most notable were increased inflammation in a handful of brain areas, including the prefrontal cortex, the brain area important for thinking.

Further research is needed

If the results can be confirmed by other larger studies, this is an important finding that depression has similarities to degenerative diseases like Alzheimer's and changes the brain in a way that research has not fully understood until now. Increased inflammation in the brain is a common reaction in degenerative brain diseases such as Alzheimer's and Parkinson's, explains the researchers.

People with depression have 30 percent higher CRP levels

These results build on a study published in 2016. This showed that patients with depression have a higher proportion of C-reactive protein (CRP) to non-diseased persons, which is another biological marker of inflammation. Overall, people with depression had 30 percent higher CRP levels than healthy people.

Depression is a biological disorder of the brain

We may need to change our thinking about depression and its effects, scientists say. The study confirms that depression is truly a biological disorder of the brain that uncontrollably degenerates to damage brain tissue - possibly in a way that resembles other neurodegenerative diseases. The findings underscore the need to develop more effective treatments, the researchers concluded. (As)