The current method of diagnosing depression is subjective. It relies on the patient’s ability to recount his symptoms and the physician’s ability and training to interpret them.
Diagnosing teens is an urgent concern because they are highly vulnerable to depression and difficult to accurately diagnose due to normal mood changes during this age period.
The test also is the first to identify subtypes of depression. It distinguished between teens with major depression and those with major depression combined with anxiety disorder. This is the first evidence that it’s possible to diagnose subtypes of depression from blood, raising the hope for tailoring care to the different types.
“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, also the David Lawrence Stein Professor of Psychiatric Diseases Affecting Children and Adolescents. “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 estimated rates of major depressive disorder jump from 2 to 4 percent in pre-adolescent children to 10 to 20 percent by late adolescence. Early onset of major depression in teens has a poorer prognosis than when it starts in adulthood. Untreated teens with this disease experience increases in substance abuse, social maladjustment, physical illness and suicide. Their normal development is derailed, and the disease persists into adulthood.