George Papakostas, MD. Director, Treatment-Resistant Depression Studies, Depression Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital
An estimated 19 million Americans are battling depression. Those affected complain of feeling sad or unhappy. They could be irritable, not sleeping, or sleeping far too much. They could complain that they’re unable to concentrate, they could have unexplained physical symptoms, or have a change in appetite. Right now, doctors diagnose depression based on patients' reported symptoms. However, the accuracy of that process varies. All that could change, though, if there were a concrete way to identify depression. New research out of Massachusetts General Hospital (MGH) is giving hope that there could eventually be a clinical tool to do just that.
A small, pilot study shows a new blood test accurately distinguishes patients diagnosed with depression from control participants. In a paper published in the journal Molecular Psychiatry, a team including MGH researchers reports a test of nine biological measures, or "biomarkers," in a patient’s blood could determine whether they are depressed. The biomarkers are associated with factors such as inflammation, neuron development and stress response in the brain structure.
The study, which was funded by Ridge Diagnostics, the firm that developed the blood test, included 36 adults who had been diagnosed with major depression, and 43 healthy control study subjects. They all took the blood test, and then the biomarker results were scored on a scale that researchers created for the study. The test accurately pinpointed depression in 90 percent of previously diagnosed depressed patients.
"Since diagnosing depression currently depends on the experience and resources of the clinician conducting the assessment, this test could help doctors who aren't as experienced in psychiatric disorders make an accurate diagnosis," says George Papakostas, MD, of the MGH Department of Psychiatry, lead and corresponding author of the report. "This test could also help verify that a patient has depression, and therefore help him or her accept the diagnosis."
"It can be difficult to convince patients of the need for treatment based on the sort of questionnaire now used to rank their reported symptoms," says study co-author John Bilello, PhD, chief scientific officer of Ridge Diagnostics. "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."
Papakostas adds, "The next step is to follow this small research study with larger trials in clinical settings, to gauge how effective it is in the real world. Eventually, this blood test may also become a tool to help us track individual patients' response to treatment."
Additional co-authors of the Molecular Psychiatry report are Brianna Bakow and Samuel Lipkin, MGH Psychiatry; Richard Shelton, MD, Vanderbilt University; Gustavo Kinrys, MD, Cambridge Health Alliance; Michael Henry, MD, St. Elizabeth's Medical Center; and Linda Thurmond, PhD, Ridge Diagnostics.