Categories of Biomarkers according to FDA-NIH BEST

BEST (Biomarkers, EndpointS, and other Tools) Resource is a FDA-NIH Joint Leadership Council initiative. The various categories of biomarkers considered include:

Diagnostic Biomarker
Monitoring Biomarker
Multicomponent Biomarker
Predictive Biomarker
Prognostic Biomarker
Response Biomarker
Safety Biomarker
Susceptibility/Risk Biomarker

A discussion of some of those relevant to cardiology with examples follows. There is some deviation from our conventional understanding of biomarkers in this concept by FDA-NIH BEST, initiated in 2016 and last updated January 7, 2025. This has also been cited in Braunwald Textbook of Heart Disease 12th Edition.

Diagnostic biomarker is used to detect or confirm presence of a disease or condition of interest or to identify individuals with a subtype of the disease. Interestingly, according to this, even ejection fraction is a diagnostic biomarker in patients with heart failure! I presume that cardiac troponins and B-type natriuretic peptides will also come under this category as well as under some other categories.

Monitoring biomarker is measured repeatedly for assessing status of a disease or medical condition or for evidence of exposure to (or effect of) a medical product or an environmental agent. International normalized ratio (INR) or prothrombin time (PT) is a monitoring biomarker in this context.

Prognostic biomarker is used to identify likelihood of a clinical event, disease recurrence or progression in patients who have the disease or medical condition of interest. C-reactive protein level may be used as a prognostic biomarker to identify patients with unstable angina or myocardial infarction with a greater likelihood of recurrent coronary artery disease events.

Safety biomarker is measured before or after an exposure to a medical product or an environmental agent to indicate the likelihood, presence, or extent of toxicity as an adverse effect. Serum potassium may be used as a safety biomarker when evaluating patients on diuretics (decreased levels), angiotensin-converting-enzyme inhibitors, angiotensin receptor blockers, or aldosterone antagonists (increased levels). Corrected QT interval (QTc) may be used as a safety biomarker to assess the potential for drugs to induce torsades de pointes.

Susceptibility/Risk Biomarker is one that indicates the potential for developing a disease or medical condition in an individual who does not currently have clinically apparent disease or the medical condition. Factor V Leiden may be used as a susceptibility/risk biomarker to identify individuals with a predisposition to develop deep vein thrombosis. C-reactive protein level may be used as a susceptibility/risk biomarker to identify adult patients with a greater likelihood of incident coronary disease.

Please note that this is not a list of all biomarkers used in cardiology, just a pointer to a relatively new concept.