Feb. 3, 2012 -- Researchers say they have developed a blood test that may reliably detect depression.
If the test continues to perform well in studies, experts say it could become one of the first objective ways to look for depression, which affects nearly 1 in 10 American adults.
“Psychiatry is a field that is begging for tests because all of our diagnoses, for the most part, are based on clinical assessments, and clinical assessments are very subjective and can be biased,” says Jennifer L. Payne, MD, a psychiatrist and co-director of the Mood Disorders Center at Johns Hopkins Hospital in Baltimore.
Payne reviewed the study for WebMD but was not involved in the research, which is published in the journal Molecular Psychiatry.
“We’d love to have tests that tell us if someone has a particular illness or not,” she says. “This is a very nice step in that direction, but there’s a heck of a lot more work to be done before this is used as a clinical test for major depression.”
The new test, called MDDScore, was developed by a company called Ridge Diagnostics. And it’s not the only objective test for depression under study.
In 2010, the company Rules-Based Medicine, which is headquartered in Austin, Texas, began offering a blood test that checks for recent-onset schizophrenia. The company is reportedly tweaking that test to make a version that looks for depression.
MDDScore measures nine indicators in blood called biomarkers that are thought to be altered in adults with major depressive disorder.
“A large number of the markers that constitute the test come from the inflammation family,” says researcher George Papakostas, MD, a psychiatrist and director of treatment-resistant depression studies at Massachusetts General Hospital.
“Chronic inflammation [is] part of a risk factor or part of the process of depression itself,” says Papakostas, who is also an associate professor of psychiatry at Harvard Medical School and a consultant for Ridge Diagnostics.
Additional indicators include hormones, growth factors, enzymes, and other proteins that act as chemical messengers.
In two studies that involved 70 people with depression and 43 people who were not depressed for comparison, the test correctly identified depression about 91% of the time and correctly ruled it out about 81% of the time.