23 Oct Emerging Research on the Biological Markers of Anxiety and Depression
Editor’s note: This piece discusses mental health issues. If you have experienced suicidal thoughts or have lost someone to suicide and want to seek help, you can contact the Crisis Text Line by texting “START” to 741-741 or call the Suicide Prevention Lifeline at 800-273-8255.
Biomarker research is rapidly evolving and new and important insights are emerging every day. Anxiety and depression are among the most prevalent and debilitating disorders, posing a major global public health burden.
Biological markers are measurable physiological, molecular or anatomical indicators of underlying biological processes. The search for reliable biomarkers holds significant promise for improving the diagnosis of anxiety and depression.
Better information guides customized treatment and helps predict therapeutic outcomes. There are several emerging lines of research. These include neuroendocrine, inflammatory, immune, genetic and neuroimaging systems. These domains are advancing our understanding of these grueling mental health conditions.
Searching for Reliable Biomarkers
Traditional diagnosis of anxiety and depressive disorders relies on symptom checklists and clinical interviews rather than objective biological measures. There is currently no blood test or imaging study that provides objective data leading to a diagnosis. This has given rise to an interest in bridging the gap between psychological symptoms and underlying biomarkers.
Recent research increasingly adopts multidisciplinary approaches, incorporating neuroimaging, genomics and gut brain axis investigations. A 2024 review described these investigations as moving toward “system biomedicine.” Researchers have begun integrating vast datasets to identify a combination of biomarkers that make up an individual patient’s fingerprint.
But the major challenges with identifying reliable biomarkers remain. These include an overlap between disorders, variability in methodologies and a lack of clinical translation.
Neurotransmitters and Hormones
Researchers are paying close attention to the effects neurotransmitters and hormonal markers have on anxiety and depression. The classic monoamine hypothesis has dominated depression and anxiety research for decades.
Newer studies are taking a closer look at how neurotransmitters affect other biological domains such as the immune system or stress hormones.
The hypothalamic pituitary adrenal (HPA) axis also regulates stress responses through cortisol secretion. Dysregulation of the HPA axis has been associated with anxiety and depression. Individuals diagnosed with depression or anxiety have demonstrated elevated or depressed cortisol responses. But these findings remain inconsistent and are likely linked to other biological markers that have not yet been identified.
A recent review of biomarkers and depression noted that neuroendocrine markers, including HPA hormones, are one of the key domains under investigation. Researchers theorize that multiple biomarkers will hold the greatest promise for guiding personalized interventions when you have major depressive disorder. This contrasts with the traditional model of studying single biomarkers in isolation.
Inflammatory and Immune System Biomarkers
Recent research has suggested that immune and inflammatory markers may be strong biomarker candidates for depression and anxiety. However, the research is only preliminary and cannot be used clinically with confidence at this time. In particular, inflammation is not present in all patients and some research suggests that only a subset of individuals with depression show elevated inflammation.
That said, emerging evidence has increasingly linked inflammation and immune dysregulation with mood and anxiety disorders. A 2025 paper indicated that high levels of pro-inflammatory proteins correlate strongly with depressive symptoms and may also predict poor treatment response. Another 2025 study introduced measurement of a multi protein that demonstrated a robust association with depression severity and somatic symptoms in study.
A 2024 study reported higher levels of a pro-inflammatory chemokine and an anti inflammatory cytokine in participants who were diagnosed with anxiety disorders and HIV. This suggested that immune marker differences may also be present in anxiety.
Genetic and Epigenetic Options
Research into genetic and epigenetic biomarkers has gained traction. A 2024 study found common risk loci that may underlie comorbidity across anxiety, depression and schizophrenia. A molecular genetics review in 2025 for anxiety disorders identified 14 risk loci and a 2024 epigenetics review examined stress induced modifications and the links to affective disorders including depression and anxiety.
The findings from these studies when taken together highlight the complex nature of mood disorders. They also inspire hope for further advances leading to more effective treatments in the future.
Brain Structure Biomarkers
Neural imaging studies are continuing to explore the structural and functional brain network alterations that occur in anxiety and depression. A study in 2024 involving 801 participants with anxiety or depression distinguished six biotypes based on brain circuit dysfunctions.
The researchers found that these biotypes differed in both their symptoms and treatment outcomes. A 2025 paper described the structural alterations in the brains of patients with anxious depression. Neural imaging showed differences in gray matter volume and structural connectivity in certain areas of the brain that may predict anxiety severity in patients with depression.
These imaging biomarkers are promising since they offer more direct insight into the brain circuit dysfunction that can occur in mood disorders. However there are significant hurdles, including high cost, variability in scanners and protocols and the need for large normative data sets before brain structure biomarkers can be used in a clinical setting.
Future Directions and Clinical Implications
The emerging research on biological markers of anxiety and depression ensures that the future of mental health care will be delivered with precision and personalization. One promising direction is the integration of multiple biological systems.
Instead of relying on a single marker like a blood test or an imaging study, researchers are exploring how patterns across inflammation, hormones and genetics might reveal distinct subtypes of anxiety and depression. Using a multifaceted approach could help clinicians match patients with treatments that are more likely to have a positive outcome.
Clinically these advancements could transform diagnosis and treatment planning. Biological markers may help identify if you have a higher risk and may reduce the trial and error approach that’s often seen in prescribing medication.
From Research to Real World Impact
The search for biological markers represents one of the most promising frontiers in modern psychiatry. Although discoveries are not yet ready for everyday clinical use they are shaping how providers think about prevention and treatment.
Future care may include a combination of laboratory tests, digital health data and imaging results alongside traditional interviews. The next era of research hopes to bridge the gap between science and practice, ensuring that biological discoveries translate into meaningful benefits.
Ultimately the goal is not to replace clinical expertise or human understanding but to improve it. Understanding the mind’s unconscious processes remains central to that mission. Psychoanalytic therapy takes this deeper look at how past experiences and hidden emotions shape present mental health.
By combining biological insight with psychological and social context, the next generation of mental health care may become more proactive, more personalized and more human than ever before.
—–
The information on MedicalResearch.com is provided for educational purposes only, and is in no way intended to diagnose, cure, or treat any medical or other condition. Some links may be sponsored. Products are not warranted or endorsed.
Always seek the advice of your physician or other qualified health and ask your doctor any questions you may have regarding a medical condition. In addition to all other limitations and disclaimers in this agreement, service provider and its third party providers disclaim any liability or loss in connection with the content provided on this website.
Last Updated on October 23, 2025 by Marie Benz MD FAAD
