Study Finds Hope For a Blood Test to Diagnose Depression
One of the biggest trials for people suffering depression is being told to “just cheer up” or “stop faking it.” When you a struggling with an invisible disease with no objective method of diagnosis, it can be difficult for some to believe there is any biologic problem. But, a new study from the Medical University of Vienna may offer hope for a future scientific diagnosis method for depression.
The study, published n PLOS ONE, indicates that it may be possible for depression to one day be detected with a simple blood test.
The researchers, under the supervision of Lukas Pezawas, used functional magnetic resonance (fMRI) images of the brain, combined with pharmacological investigations, to show a close tie between the speed of serotonin uptake within blood platelets and the function of a depression network in the brain.
Lack of serotonin is commonly believed to facilitate depression, and the transport of the neurotransmitter into a cell is assisted by a protein in the cell membrane called the serotonin transporter. (SERT).
SERT is found in the brain, but it can also be seen in large quantities throughout organs such as the intestines, as well as the blood. The SERT found in blood ensures that platelets maintain the proper level of serotonin in the blood plasma. The ability of SERT to transport serotonin regulates neural depression networks.
The specific network focused on in the study is known as the “default mode network” because it is mostly active at rest and processes content with strong self-reference. Previous research has shown that the network is actively supressed during mental activities that require a lot of thought processes, which allows for concentration. It is also true that many people with depression experience difficulties with thinking and concentration, due to an inability to suppress the default mode network.
“This is the first study that has been able to predict the activity of a major depression network in the brain using a blood test. While blood tests for mental illnesses have until recently been regarded as impossible, this study clearly shows that a blood test is possible in principle for diagnosing depression and could become reality in the not too distant future,” explained Pezawas.
If the processes of the depression network can be measured in the blood, it could mean depression may be able to be diagnosed through blood tests in the close future.