A Clinician's Perspective on Biomarkers

Abstract

Psychiatrists and mental health professionals regularly perform various clinical tasks (e.g., detection, differential diagnosis, prognostication, treatment selection and implementation). How well they perform each of these tasks has a direct impact on patient outcomes. Measurement-based care has brought greater precision to these tasks and has improved outcomes. This article provides an overview of the types of biomeasures and biomarkers, the clinical uses of biomarkers, and the challenges in their development and clinical use. Although still in their infancy, biomarkers hold the promise of bringing even greater precision and even better outcomes in mental health. Biomeasures that could become biomarkers include genetic, proteomic, metabolomic, and immunologic measures, as well as physiological, functional, and brain structural measures. Mechanistic markers reflect and are based on the specific pathobiological processes that are involved in the development of a clinically defined condition. Some clinically relevant biomarkers may rely on this mechanistic understanding while others may not. Clinical biomarkers serve three broadly defined goals. Diagnostic markers define what is wrong. Prognostic markers define what will happen in the natural course of the condition, although they may also predict the course of illness during treatment. Theranostic markers address issues pertinent to treatment by defining whether, when, whom, and how to treat. Other biomarkers may be used to monitor the overall effect of treatment regardless of the therapeutic effects or to monitor the specific therapeutic effects of the intervention on the disorder itself. Biomarkers can also be used to estimate susceptibility/risk of developing the condition or the biological consequences of having had the disorder.

Keywords: bio-measures; biomarker; prognostication. diagnosis; psychiatry; treatment selection.

FIGURE 1.

Antecedents, Concomitants, and Consequences of Illness Episodes^{a a}Copyright 2018 Curbstone Consultant LLC. Reprinted with permission

FIGURE 2.

Molecular Biomeasures: The Personal Omics Profile^{a a}Adapted from Chen and Snyder (27). Reprinted from Current Opinion in Psychiatry. Copyright 2012. Reprinted with permission

FIGURE 3.

Biomarker Categories^{a a}Copyright 2018 Curbstone Consultant LLC. Reprinted with permission

FIGURE 4.

Baseline C-Reactive Protein (CRP) Levels Moderate Remission in Depression^{a a}CO-MED, Combining Medications to Enhance Depression Outcomes; SSRI, selective serotonin reuptake inhibitor. Source, Jha et al. (77). Reprinted from Psychoneuroendocrinology. Copyright 2017. Reprinted with permission

FIGURE 5.

Personalized Care Indicator^{a a}SCL-90, Symptom Checklist–90. Source, Judd et al. (86). Copyright 2016 American Psychiatric Association. Reprinted with permission