Using serum cholesterol to identify high risk and stimulate behavior change: will it work?

Area of Science:

• Cardiovascular Medicine
• Preventive Cardiology
• Biostatistics

Background:

• Serum cholesterol measurement aims to identify high-risk individuals for coronary heart disease (CHD) and motivate behavior change.
• Previous research confirmed the motivational impact of cholesterol testing.

Purpose of the Study:

• To evaluate the discriminative ability of serum cholesterol levels in identifying men at high risk of death from CHD.
• To assess the accuracy of serum cholesterol as a predictor of CHD mortality in middle-aged men.

Main Methods:

• Analysis of a US male cohort aged 40-59 at entry.
• Evaluation of serum cholesterol's ability to discriminate between individuals who died from CHD and those who did not.
• Receiver operating curve (ROC) analysis and Monte Carlo simulations were employed.

Main Results:

• Increasing serum cholesterol correlated with increased CHD death risk, but significant overlap existed between diseased and non-diseased groups.
• Test accuracy decreased as the definition of "high risk" expanded; 5% high-risk definition yielded 92% accuracy, 50% yielded 55%.
• ROC analysis showed a 5% false positive rate with an 8% true positive rate when defining 5% as high risk; 50% high risk increased true positives to 75% but false positives to over 50%.

Conclusions:

• Serum cholesterol effectively discriminates high-risk individuals but with limitations in accuracy depending on the threshold.
• Population-wide cholesterol reduction of 0.78 mmol/l could decrease CHD deaths by 28%.
• Targeted reduction in the top 20% of cholesterol distribution could achieve similar mortality benefits.