�鶹��

By Henrik Larsen

This discovery advances our understanding of the causes of major depressive disorder and indicates the need to target novel therapies. “These could include a combination of psychedelic compounds and psychotherapy,” says head of the Danish research project, Professor Vibe Frøkjær.

A Danish research team is the first to demonstrate that healthy individuals with a specific brain chemistry and psychological profile have a long-term risk for developing major depressive disorder.

This discovery has just been published in Nature Mental Health, one of the world’s most important scientific journals. The study was conducted by researchers from Rigshospitalet, University of Copenhagen and Mental Health Services in the Capital Region of Denmark.

The Nature article reveals that otherwise healthy individuals, oblivious to the existence of this threat to their mental health, are at high risk for depression stemming from an interaction between two factors:

Psychologically, a personality profile characterised by high neuroticism, including pronounced anxiety, self-consciousness and a low threshold for enduring stress.

Brain chemistry, involving receptors which mediate the brain’s internal communication by means of serotonin (serotoni n2A receptor type in particular), a signalling substance.

“When these personality and brain chemistry factors are present at the same time in an individual, their long-term risk for major depression increases. This is what we have been able to demonstrate,” explains Frøkjær, Professor in Neuropsychiatry at the Neurobiology Research Unit (NRU) at Rigshospitalet and Mental Health Services, Capital Region of Denmark. Frøkjær headed up the team that published the Nature article, and received research funding from the Lundbeck Foundation and Innovation Fund Denmark.

This discovery advances our understanding of major depressive disorder, which is very promising,” says Professor Frøkjær, adding: 

“Anyone can develop depression, and in some cases, it appears to come on with no warning. But the better we understand the complex interactions of psychological and brain chemistry factors underlying depression, the better we’ll be able to treat and prevent this mental disorder. Our discovery also points to the necessity in some cases of being open to 

using new modes of treatment for depression. These could include a combination of psychotherapy and psychedelic compounds such as psilocybin. This is another important finding we made,” explains Frøkjær.

WHO ARE AT RISK?

The distinct depression-risk link between personality traits and brain chemistry discovered by the Danish research team raises the question: How many people have this profile?

“The study does not set out to estimate this number in the Danish population, but it offers important insights into a specific profile that is associated with heightened risk for depression- a finding we hope will take us one step closer to understanding the disorder’s complex pathophysiology.” says Anjali Sankar, from the Neurobiology Research Unit (NRU) at Rigshospitalet. Sankar who holds a PhD in psychology and neuroscience, is the first author of the Nature article, and spearheaded the analyses that resulted in discovery of the special risk profile.

“We studied a total of 131 healthy individuals who underwent brain scans and psychometric testing, with a subsequent 19 years of follow up in Danish health registries. In addition to the specific risk profile that is associated with developing a future depressive episode, we found that the risk for depression measured over the entire period was 24 percent in women as opposed to seven percent in men. This reflects the reality we’re already familiar with from depression studies: that women are far more likely than men to be diagnosed with major depressive disorder,” says Sankar. 

But now that the risk profile among healthy individuals for being diagnosed with severe depression has been established, it should be possible to put that knowledge to use in devising a form of screening test, as a kind of early warning of future depression.

Although that is an interesting idea, it is not exactly possible to do in practice, as Professor Frøkjær explains:

“As I see it, the best thing is to try to live naturally, making the most of life without harm to our mental health. And the aim should be to concentrate on stress management, and coming to terms with the inevitability and necessity of occasional adversity in life.”