15 - Biomarkers in vascular disease

Summary

INTRODUCTION

Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in the developed world. These diseases encompass the consequences of localized atherosclerosis and aneurysmal arterial degeneration. Evolution of risk factors contributes to the onset of subclinical disease; subclinical disease progresses to overt and often catastrophic clinical sequelae. Primary and secondary prevention strategies for CVD are public health priorities.

Whilst clinical assessment and crosssectional imaging remain the cornerstones of patient management, they have limitations. There is increasing interest in the use of novel markers of cardiovascular disease as screening and risk-assessment tools to enhance the ability to identify the ‘vulnerable’ patients. Biomarkers are one tool to aid clinical assessment and identify high risk individuals, to ensure prompt and accurate disease diagnosis and to aid prognostic scoring of individuals with disease.

WHAT IS A BIOMARKER?

Initially described as a ‘measurable and quantifiable biological parameter that could serve as an index for health assessment’, the definition of a biomarker has since been standardized.

‘A characteristic that is objectively measured as an indicator of normal biological pro cesses, pathogenic processes, or pharmacological responses to a therapeutic intervention’

Biomarkers are indicators of disease trait (risk factor or risk marker), disease state (preclinical or clinical), or disease rate (progression). They may also serve as surrogate end points used as an outcome measure to assess efficacy of therapy. A biomarker may be a recording taken from an individual (e.g. blood pressure), it may be an imaging test (CT / PET scan), or it may be a biosample (blood, serum, urine).