Ongoing research at Cambridge University promises significant breakthroughs to augment subjective clinical assessments of patients with mental illnesses through the use of blood tests.
The Neuro Tech 2023 event which took place in London on December 2023 was focused on the latest advances in the technology and management of neurological conditions. In her lecture “Development of a combined digital and biomarker test for bipolar disorder,” Prof. Sabine Bahn detailed her ongoing research on the use of blood tests to help diagnose psychiatric conditions.
A practicing psychiatrist whose main research is focused on understanding the molecular basis of neuropsychiatric disorders, Sabine Bahn is Chair in Neurotechnology, Director of the Center for Neuropsychiatric Research at Cambridge University and Chair in Translational Neuropsychiatry at the Erasmus Medical Center in Rotterdam.
According to her, diagnosing psychiatric patients presents great difficulty. Currently, this process is fully dependent on the subjective clinical evaluation of symptoms which are self-reported by patients. One of the main disadvantages of this process is the fact that symptoms often overlap between different conditions.
For example, distinguishing depressive episodes in bipolar disorder from those in major depressive disorder is extremely difficult, as patients with bipolar disorder often only seek help during depressive phases and may not fully recognize or report their manic or hypomanic episodes. And this difficulty doesn’t end when a patient finally receives the correct diagnosis.
Treating mental illnesses often involves many adjustments in the prescription of drugs and their dosage before the best, desired outcome is reached. Sabine Bahn explained:
“The hope for blood-based tests in psychiatric practice is to make the diagnostic process more accurate, faster and more objective.
They would complement subjective clinical assessments done through traditional clinical evaluation; and that would result in more personalized treatment plans, and ultimately, better outcomes for patients.”
Identifying Biomarkers of Psychiatric Conditions
The initial aim of her team at Cambridge University was to use molecular profiling techniques to globally investigate abnormalities in gene/protein/metabolite/lipid “expression” in post-mortem human brain, blood and other tissue samples.
Over the last five years, however, the focus has shifted to developing blood-based diagnostic tests for mental disorders. She added:
“The current work in our lab is focused on identifying biomarkers of psychiatric conditions, especially mood disorders such as bipolar disorder and major depressive disorder.
These biomarkers may not only indicate the presence of a disease but could also serve as potential targets for existing or new treatments.
We previously used such biomarkers, identified in patient blood cells, as targets during a drug screening process in schizophrenia. It showed, for example, that drugs used for hypertension and immune conditions were effective on the schizophrenia drug target, suggesting new treatment opportunities for testing in clinical trials.”
Promoting Effective Treatment Sooner
At present, all the drugs are being tested in vitro on patient-derived cells or tissues, to evaluate how they interact with the identified biomarkers.
The research carried out so far indicates several promising directions for the improved treatment of bipolar disorder. Equally important, by facilitating earlier diagnosis, a blood test could promote effective treatment sooner, therefore preventing unnecessary suffering.
Sabine Bahn said:
“This is crucial because about half of the patients with bipolar disorder are initially misdiagnosed and it takes an average of five to seven years to receive a correct diagnosis and appropriate treatment.”
Her group’s experiments point to another advantage of using the tests: monitoring treatment response, as they make it possible to track the biomarkers. And some of these biomarkers can be used as references when testing different drugs.
“For example, consistent with our top biomarker identified for bipolar disorder, the ceramide system [ceramides are a family of waxy lipid molecules] is emerging as a promising target in mood disorders.”
The group’s previous research with post-mortem tissue had already indicated increased ceramide levels in the brains of patients with bipolar disorder. Now this conclusion is being validated by the results involving living patients.
