Researchers develop blood test that could help gauge depression, bipolar disorder

A new study from researchers in Indiana found a way to test someone’s blood to gauge depression, opening the door for changes in diagnosing and treating mental illness.  

The study was done by researchers from the Indiana University School of Medicine, who found a way to distinguish from a blood test how severe a patient’s depression is, the risk of them developing severe depression in the future and the risk of future bipolar disorder.

The study took place over four years and included more than 300 participants. 

Researchers tracked when the participants were in high and low moods, and noted changes in their blood between the two states.

Researchers looked at these biological markers - or biomarkers - in the blood and cross-referenced them with those in a different group of clinically severe people with depression or mania. Commonalities were found as a way to predict who is ill, and who could become ill in the future.  

"Blood biomarkers are emerging as important tools in disorders where subjective self-report by an individual, or a clinical impression of a health care professional, are not always reliable. These blood tests can open the door to precise, personalized matching with medications, and objective monitoring of response to treatment," said Dr. Alexander B. Niculescu, who led the study and is a professor of psychiatry at the school. 

"Through this work, we wanted to develop blood tests for depression and for bipolar disorder, to distinguish between the two, and to match people to the right treatments," he continued.

Niculescu said the research opens doors to more precise diagnoses as well as helping with new drug development. 

"This is part of our effort to bring psychiatry from the 19th century into the 21st century. To help it become like other contemporary fields such as oncology. Ultimately, the mission is to save and improve lives," he said.

More than 19 million adults in the United States - or about 8% of the population - had at least one major depressive episode in the past year, the National Alliance on Mental Illness reports. 

The study was published in the journal Molecular Psychiatry.

Niculescu and his colleagues have also researched blood biomarkers that track suicidality as well as pain, post-traumatic stress disorder and Alzheimer’s disease.