New research suggests a link between biological aging and depression, pointing to a potential blood biomarker for the mood disorder. The study, published in The Journals of Gerontology, examined the relationship between the aging of white blood cells and depressive symptoms.
Researchers analyzed data from 261 women with HIV and 179 without HIV, all participants in the Women’s Interagency HIV Study. Depression levels were measured using the Center for Epidemiologic Studies Depression Scale, while blood tests assessed the biological age of white blood cells, particularly monocytes. Monocytes play a key role in HIV infection and are often elevated in people with depression.
The results showed that monocyte aging was a biomarker for non-somatic depression symptoms, such as hopelessness, loss of joy, and feelings of failure, in both groups of women. Study co-author Nicole Beaulieu Perez, Ph.D., noted that people with HIV often have physical symptoms like fatigue that are attributed to their chronic illness rather than depression. “But this flips that on its head because we found that these measures are associated with mood and cognitive symptoms, not somatic symptoms,” she said in a news release.
Identifying a biological marker for depression is significant because the condition is almost always diagnosed based on self-reported symptoms. “Depression is not a one-size-fits-all disorder—it can look really different from person to person, which is why it’s so important to consider varied presentations and not just a clinical label,” Beaulieu Perez said. She added that the study reveals “unique biological underpinnings of mental health that are often obscured by broad diagnostic categories.”
The study authors said more research is needed to fully understand the connection between biological aging and mood disorders. However, the findings offer promise for future diagnostic and treatment approaches. “I think about the adage, ‘What gets measured gets managed.’ An aspirational goal in mental health would be to combine subjective experience with objective biological testing,” Beaulieu Perez said.
Depression and other mood disorders take a major toll on those affected, making accurate diagnosis and effective treatment essential. This study points to a new way of understanding the connection between the body and mind. Beaulieu Perez said the findings “bring us a step closer to this goal of precision mental health care, especially for high-risk populations, by providing a biological framework that could guide future diagnosis and treatment.” The research was published in The Journals of Gerontology.
