Biomarkers in psychiatry: drawbacks and potential for misuse

Abstract

For more than 20 years, researchers have attempted to identify diagnostic and prognostic biomarkers for psychiatric disorders including schizophrenia, major (unipolar) depression, and bipolar disorder. Advocates of this research contend that identifying such biomarkers will aid in the diagnosis of these disorders, as well as the possible development of effective psychiatric medications to treat them. Currently, there are no diagnostic tests available. This is largely due to the multi-factorial nature of psychiatric disorders. Biomarker testing of individuals is also prohibitively expensive because significant expertise is required to conduct tests and follow-up counseling for the patient is often necessary. It is cautioned that widespread biomarker testing could lead to negative consequences such as discrimination in health insurance and employment, as well as selective abortion.

Differential expression of microRNA in peripheral blood mononuclear cells as specific biomarker for major depressive disorder patients

“…But diagnosis of MDD is often difficult due to the fact that there is no effective diagnostic biomarker available. Despite decades of efforts on peripheral/ serum growth factors, cytokines, hormones, and metabolic markers, a non-invasive, quantitative clinical test to aid the diagnosis of MDD remains elusive (Lakhan et al, 2010). However, miRNAs in peripheral blood represent a new potential approach for non-invasive and rapid diagnostic screening for many diseases (Ajit, 2012).…”

Discovery of blood transcriptomic markers for depression in animal models and pilot validation in subjects with early-onset major depression

“…17 Two approaches have been used to search for blood biomarkers. The first approach screens candidate markers suggested by current knowledge of MDD etiology, such as serum levels of cortisol 18 or brain-derived neurotrophic factor.…”

Serum Levels of Mature Brain-Derived Neurotrophic Factor (BDNF) and Its Precursor proBDNF in Healthy Subjects

“…Identification of biomarkers in human body fluids such as blood, urine, and cerebral spinal fluid (CSF) would aid both in the diagnosis of neuropsychiatric diseases, and development of effective therapies [1]. Mature brain-derived neurotrophic factor (BDNF) is a 13 kDa polypeptide, known to play an important role in the survival, differentiation, and outgrowth of select peripheral and central neurons during development and adulthood [2,3].…”