Major depressive disorder is one of the most common mental health conditions in the world. It affects hundreds of millions of people and can deeply disrupt daily life.
People living with depression often feel persistent sadness, low energy, loss of interest in activities they once enjoyed, trouble sleeping, changes in appetite, and difficulty concentrating. For many, even simple tasks can feel overwhelming.
Doctors have several ways to treat depression, including counseling and medications. The most widely prescribed medicines are called selective serotonin reuptake inhibitors, or SSRIs. These drugs work by increasing levels of serotonin, a chemical in the brain that helps regulate mood, sleep, and emotions.
While SSRIs can be very effective, they do not work for everyone. Many patients must try different medications over weeks or months before finding one that helps. This trial-and-error process can be frustrating and exhausting, especially when symptoms remain severe.
Scientists have long searched for a way to predict which medication will work best for each person. Now, researchers from several institutions, including Circular Genomics and the University of New Mexico, have discovered a possible clue in the blood.
They identified a biological marker that may help doctors know in advance whether a patient will respond well to a specific antidepressant.
The marker is a type of genetic material called circular RNA, specifically one known as CDR1as. Unlike the genes that produce proteins, this material does not create proteins but still plays an important role in controlling how cells function.
Circular RNAs are especially active in the brain and are involved in brain development and communication between nerve cells. They are also very stable, meaning they can be measured reliably in blood samples.
In the study, researchers collected blood samples from people diagnosed with major depression before they began treatment. They measured the levels of CDR1as and then followed the patients as they took a commonly prescribed SSRI called sertraline.
The scientists found that people who later improved on the medication had different levels of this marker compared to those who did not benefit from the drug.
Even more interesting, the levels of CDR1as changed after successful treatment, and these changes were linked to long-term recovery. This suggests that the marker not only predicts response but may also reflect how the brain adapts during treatment.
The research team also studied brain cells and animal models to better understand how this molecule interacts with serotonin and another important brain factor related to nerve growth and resilience.
The findings raise the possibility of a future where a simple blood test could guide treatment decisions for depression. Instead of guessing which medication might work, doctors could choose a drug based on a patient’s biological profile.
This approach, often called personalized medicine, aims to tailor treatment to each individual rather than using the same method for everyone.
However, the study has limitations. It focused mainly on one medication, sertraline, so more research is needed to see whether the marker predicts response to other antidepressants.
Larger studies are also required before the test can be used in everyday medical practice. Mental health is complex, and many factors, including life experiences, stress, and physical health, influence how someone responds to treatment.
In analyzing the findings, the research represents an important step toward more precise and compassionate care for people with depression. The current trial-and-error approach can delay recovery and increase suffering.
If confirmed by future studies, this discovery could shorten the time it takes for patients to find relief and reduce the burden on healthcare systems.
Overall, the study highlights the growing role of biology in understanding mental health. It shows that depression is not simply a matter of feelings but involves measurable changes in the body and brain. By learning more about these changes, scientists hope to improve treatment and help people return to fulfilling lives more quickly.
If you care about mental health, please read studies about how dairy foods may influence depression risk, and 6 foods you can eat to improve mental health.
For more mental health information, please see recent studies about top foods to tame your stress, and Omega-3 fats may help reduce depression.
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