Blood markers offer hope for early detection of teen depression

Using a novel lab method they developed, McGill University researchers have identified nine molecules in the blood that were elevated in teens diagnosed with depression. These molecules also predicted how symptoms might progress over time.

The findings of the clinical study could pave the way for earlier detection, before symptoms worsen and become hard to treat.

Alarmingly, more and more adolescents are being diagnosed with depression, and when it starts early, the effects can be long-lasting and severe. Teens with depression are more likely to struggle with substance use, social isolation and experience symptoms that often don't respond well to treatment."

Cecilia Flores, senior author, James McGill Professor in McGill's Department of Psychiatry, researcher at the Douglas Research Centre and principal investigator at the Ludmer Centre

Notably, the nine molecules – known as microRNAs – have not been linked to adult depression, suggesting they reflect biological processes unique to teens.

A minimally invasive and scalable approach

The study, conducted in collaboration with colleagues at the University of California, Los Angeles and Stanford University, focused on 62 teenagers: 34 with depression and 28 without. Researchers collected small volumes of blood samples, let them dry, and then froze the samples to preserve molecular integrity over time. Such samples are taken with a simple finger prick and are easy to store and transport, making the approach practical and scalable for broader use.

The McGill team developed the lab method used to extract and analyze microRNAs from the samples.

"Our findings pave the way for using dried blood spots as a practical tool in psychiatric research, allowing us to track early biological changes linked to mental health using a minimally invasive method," said first author Alice Morgunova, postdoctoral fellow at McGill.

Diagnosing depression mostly relies on self-reported symptoms. The authors say this could delay care, especially if teens don't recognize the signs or aren't ready to talk about them. A blood-based screening tool could provide an additional and more objective metric to identify teens at risk.

The researchers plan to validate their findings in larger groups of adolescents and to study how these microRNAs interact with genetic and environmental risk factors.

About the study

"Peripheral microRNA signatures in adolescent depression" by Alice Morgunova and Cecilia Flores et al., was published in Biological Psychiatry Global Open Science.

The study was funded by the Douglas Foundation and Bombardier Fund grant, the National Institute on Drug Abuse of NIH, the Canadian Institutes of Health Research, the Natural Sciences and Engineering Research Council of Canada, a Healthy Brains for Healthy Lives Graduate Student Fellowship, an Integrated Program in Neuroscience Internal Award, and Postdoctoral Fellowship from the McGill-Douglas Max Planck Institute of Psychiatry International Collaborative Initiative in Adversity and Mental Health, an international partnership funded by the Canada First Research Excellence Fund, awarded to McGill University for the Healthy Brains for Healthy Lives initiative.