Blood Test to diagnose schizophrenia and depression
By Catherine Walker
A great deal of interest has been drawn to a newly developed blood test for schizophrenia and depression. This has been designed to augment the current diagnostic approaches.
Professor Sabine Bahn, MD, PhD, MRCPsych, Director of the Cambridge Centre for Neuropsychiatric Research (CCNR) and Director/Co-founder of Psynova Neurotech Ltd. has described her 15-year search for biomarkers of neuropsychiatric disorders and the development of VeriPsych at this years American Psychiatric Association’s annual meeting in Hawaii. VeriPsych is reportedly the first blood-based diagnostic test to confirm the presence of recent-onset schizophrenia. It is not a genetic test but an automated test that uses a single serum sample to identify 51 protein biomarkers. It’s design is to help mental health professions reach a diagnosis.
The search for biomarkers in psychiatric disorders is a personal quest for Prof Bahn as her father had bipolar disorder. Bahn is also the Chair of Translational Neuroscience at Erasmus Medical Centre in Rotterdam, Netherlands.
Biomarkers have many applications, Bahn explained at the American Psychiatric Association meeting. These include the identification of high-risk individuals and disease subgroups that could serve as target populations or intervention trials, facilitation of ‘objective’ diagnosis, monitoring of patient response to drug treatments, and assessment of patient compliance.
Bahn says that she, and more than 20 scientists at CCNR, are seeking to develop molecular diagnostics for major neuropsychiatric disorders and to determine the cellular mechanisms that regulate the expression of biomarker molecules altered in these states so as to develop novel therapeutic approaches.
Bahn also said that the CCNR laboratory uses advanced molecular profiling techniques (microarrays, proteomics, lipidomics and metabolomics) to globally investigate abnormalities in gene/protein/metabolite/lipid ‘expression’ in postmortem human brain tissue and in blood and other samples derived from patients and matched controls, to establish evidence-based hypotheses.
For example, Bahn told APA attendees that in the team’s examination of postmortem brain tissue of patients with schizophrenia, they found evidence of abnormal glucose utilization. Schizophrenia, she said might be considered ‘diabetes of the brain’.
“Our findings suggest alterations in glucoregulatory processes in CSF of drug-naive patients with first-onset schizophrenia. Short-term treatment with atypical antipsychotic medication resulted in a normalization of the CSF disease signature in half the patients well before a clinical improvement would be expected,” she said.
Bahn’s team discovered a set of 51 biomarkers with linkages to schizophrenia and to various biochemical pathways, including inflammation and metabolism, as well as cell-to-cell signaling.
In a subsequent study, the 51 biomarkers were validated in combination with a mathematical process to separate patients with schizophrenia from normal controls. The study included analysis of more than 800 blood samples. The panel of 51 markers yielded an average sensitivity and specificity of 85% or greater across 5 clinical centres, according to Bahn.
