A Blood Test for Depression

Biomarkers in blood tests may help physicians diagnose major depressive disorder

(RxWiki News) A blood test to identify depression is on the horizon, and could represent a major breakthrough in the diagnosis of depressive disorder.

By analyzing nine biomarkers, patients with depression could be accurately distinguished from people not suffering from depression.

"As your doctor about new blood tests for depression."

A team of researchers led by George Papakostas, MD, of Massachusetts General Hospital (MGH) enrolled 36 adults who had already been diagnosed with major depression, along with 43 control participants who were not depressed.

Using a blood test developed by Ridge Diagnostics, which sponsored the study, researchers measured the levels of nine biomarkers associated with such things as inflammation, stress response and the development and maintenance of neurons.

Using a specific formula to arrive at the patients' MDDScore - a number between one and 100 that indicates the likelihood of an individual having major depression - researchers found scores that indicated depression in 33 out of the 36 depressed subjects. Only eight of the 43 non-depressed control subjects gave a positive test result for depression.

The average MDDScore for the depressed group was 85, while the average for controls was 33. The research team followed that study up with a second replication phase using an additional 34 patients. The combination of both study groups indicated that the new test could accurately diagnose major depression with a detection rate of around 90 percent, and a specificity (ability to rule out the condition) of 80 percent.

"Traditionally, diagnosis of major depression and other mental disorders has been made based on patients' reported symptoms, but the accuracy of that process varies a great deal, often depending on the experience and resources of the clinician conducting the assessment," said Dr. Papakostas.

"Adding an objective biological test could improve diagnostic accuracy and may also help us track individual patients' response to treatment."

There have been previous efforts to develop biomarker tests for depression, but they failed to produce results with enough sensitivity to detect the condition.

"We expect that the biological basis of this test may provide patients with insight into their depression as a treatable disease rather than a source of self-doubt and stigma," said study co-author John Bilello, PhD, chief scientific officer of Ridge Diagnostics.

The results were published in a recent issue of Molecular Psychiatry. 

Review Date: 
February 7, 2012