A Blood Test Can Diagnose Depression
A breakthrough in the mental health field may have been uncovered as a new study from Northwestern University claims a new blood test is the first objective and scientific test able to diagnose major depression in adults.
The test evaluates the levels of nine genetic indicators, known as RNA markers, in the blood. It would not only allow doctors to objectively diagnose depression, but would also make it possible to detect if cognitive behavioral therapy will be effective and identify if the treatment is working after is has begun.
One of the biggest obstacles in the early identification of depression is the gradual onset. Typically this leads to a delay between start of symptoms and diagnosis that often ranges between two months to forty months.
“The longer this delay is, the harder it is on the patient, their family and environment,” said lead researcher Eva Redei, a professor in psychiatry and behavioral sciences and physiology at Northwestern’s Feinberg School of Medicine in Chicago.
“Additionally, if a patient is not able or willing to communicate with the doctor, the diagnosis is difficult to make,” she said. “If the blood test is positive, that would alert the doctor.”
The study, published online in Translational Psychiatry, evaluated the test’s effectiveness with 32 adults who had previously been diagnosed with depression and 32 adults with no history of the condition. All participants were between the ages of 21 and 79 years old.
The researchers administered the blood test to all participants in the study, then those with depression underwent 18 weeks of face-to-face or phone therapy. After the weeks of therapy, 22 participants were retested.
The findings showed that depressed patients who recovered with therapy had noticeable differences in their RNA markers before and after the therapy, while those who remained depressed maintained their original levels. The researchers also noted that three RNA markers remained unique from non-depressed participants after the study, which they believe may indicate susceptibility to depression.
The test’s accuracy in diagnosing depression in testing is approximately equal to standard psychiatric diagnostic interviews, which are about 72 percent to 80 percent effective.