14 DAY TRIAL // A researcher from the Psychoimmunology Unit at Lund University discovered that depressed and suicidal people have low levels of cortisol in their blood and saliva, and he also found substances in their spinal fluid which suggest an increased inflammation in the brain.
The finding of these two anomalies could lead to the development of new ways of diagnosing and treating suicidal individuals.
In Doctor Daniel Lindqvist's PhD thesis, he presents studies which conclude that depressed patients, with a serious intention of committing suicide have low levels of the stress hormone cortisol in their blood.
In addition to that, in the saliva of individuals who attempted suicide, cortisol levels were found to be low even several years after the attempt.
This could only mean that the depression led to some kind of 'breakdown' in the stress system, thus the low level of stress hormones, the researchers concluded .
In an article of the thesis, Lindqvist writes that suicidal patients had abnormally high levels of cytokines (substances related to inflammation) in their spinal fluid.
Patients who have been diagnosed with major depression, or those who have made violent suicide attempts (like trying to hang themselves), had the highest levels of cytokines.
This theory had got the attention of the research group at the Division of Psychiatry in Lund, who are now preparing a treatment study based on it – they will administrate depressed patients an anti-inflammatory medication, hoping it will reduce the symptoms.
The cause of the inflammation that starts the process is uncertain: the researchers hypothesize that it could be serious influenza, or a severe allergy, or even an auto-immune disease like rheumatism, that leads to inflammation in the body.
They speculate that a certain genetic weakness might be involved, like some gene variants that make more people more sensitive than others.
Dr Lindqvist is a member of the research team led by Dr Lena Brundin, who believes that there is a strong connection between inflammation in the brain and depression.
Their belief actually opposes the general opinion, according to which depression is only caused by a lack of serotonin and noradrenaline.
“However, current serotonin-based medication cures far from all of the patients treated,” Daniel Lindqvis said.
“We believe that inflammation is the first step in the development of depression and that this in turn affects serotonin and noradrenaline.”
And because there is nothing difficult in taking and analyzing blood and saliva samples, “cortisol and inflammation substances could therefore be used as markers for suicide risk and depth of depression.”