April 20, 2012

Breakthrough Test Identifies Depression

(Ivanhoe Newswire)–A Northwestern Medicine scientist has developed the first blood test to diagnose major depression in teens. A breakthrough approach that allows an objective diagnosis by measuring a specific set of genetic markers found in a patient's blood.

Untreated teens with major depression experience increases in substance abuse, social maladjustment, physical illness and suicide. Their normal development is derailed, and the disease persists into adulthood.

"Right now depression is treated with a blunt instrument," said Eva Redei, a professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine and lead investigator of the study, published in Translational Psychiatry. "It's like treating type 1 diabetes and type 2 diabetes exactly the same way. We need to do better for these kids."

"This is the first significant step for us to understand which treatment will be most effective for an individual patient," added Redei. "Without an objective diagnosis, it's very difficult to make that assessment. The early diagnosis and specific classification of early major depression could lead to a larger repertoire of more effective treatments and enhanced individualized care."

The study subjects included 14 adolescents with major depression who had not been clinically treated and 14 non-depressed adolescents, all between 15 to 19 years old. The depressed and control subjects were matched by sex and race.

Redei's lab tested the adolescents' blood for 26 genetic blood markers she had identified in previous research. She discovered 11 of the markers were able to differentiate between depressed and non-depressed adolescents. In addition, 18 of the 26 markers distinguished between patients that had only major depression and those who had major depression combined with anxiety disorder.

"These 11 genes are probably the tip of the iceberg because depression is a complex illness," Redei said. "But it's an entry into a much bigger phenomenon that has to be explored. It clearly indicates we can diagnose from blood and create a blood diagnosis test for depression."

Further indicating the challenge in working with depressed adolescents, none of the teens who were diagnosed with depression opted for treatment.

"Everybody, including parents, are wary of treatment, and there remains a social stigma around depression, which in the peer-pressured world of teenagers is even more devastating," Redei said. "Once you can objectively diagnose depression as you would hypertension or diabetes, the stigma will likely disappear."

SOURCE: Northwestern University, April, 2012