Plasma lipid concentrations: the concept of "normality" and its implications for detection of high cardiovascular...

Area of Science:

• Cardiology
• Epidemiology
• Biochemistry

Background:

• The relationship between serum cholesterol and coronary heart disease (CHD) incidence is continuous and curvilinear.
• No epidemiological or biological evidence supports a threshold for serum cholesterol levels.
• Raised cholesterol is causally linked to atherosclerotic heart disease, necessitating clinical action limits.

Purpose of the Study:

• To establish clinically relevant action limits and desirable ranges for serum cholesterol.
• To guide clinicians in managing patients at risk of coronary heart disease.
• To address the need for defining treatment thresholds in the absence of a biological safety limit.

Main Methods:

• Review of epidemiological and biological evidence on cholesterol and heart disease.
• Analysis of proposed cutoff points by the European Atherosclerosis Society.
• Consideration of population cholesterol distribution in the United Kingdom.

Main Results:

• Serum cholesterol and CHD incidence show a continuous, curvilinear relationship without a threshold.
• European Atherosclerosis Society proposed cutoff points aid in treatment decisions, considering other risk factors.
• Age-adjusted limits are unnecessary as cholesterol changes in adulthood appear unphysiological.

Conclusions:

• Clinical action limits for serum cholesterol are essential for managing atherosclerotic heart disease risk.
• A case-finding strategy is needed in the UK to identify individuals at very high risk.
• While informative, measurements of triglycerides, HDL, apolipoproteins, and hyperlipoproteinemia investigation are less critical than cholesterol levels.