What blood markers should be used to screen for cardiovascular disease risk in adult patients, particularly those with a family history of cardiovascular disease or other risk factors?

Blood Markers for Cardiovascular Disease Risk Screening

All adults should have a fasting lipid profile (total cholesterol, LDL-C, HDL-C, and triglycerides) measured starting at age 20 if risk factors are present, or at age 40 for men and age 45 for women without risk factors, repeated at least every 5 years. 1, 2

Core Blood Markers for Standard Screening

Lipid Panel (Primary Screening Tool)

• Fasting lipid profile is the cornerstone blood test and must include: 1, 2, 3

  • Total cholesterol
  • LDL cholesterol (calculated by Friedewald equation if triglycerides <300 mg/dL, or measured directly)
  • HDL cholesterol
  • Triglycerides
  • Non-HDL cholesterol (calculated as total cholesterol minus HDL-C)

• Total cholesterol and HDL can be measured non-fasting if a fasting sample is unavailable, though fasting is preferred for complete assessment 1, 2

• Abnormal results must be confirmed with a repeated sample on a separate occasion, using the average of both results for risk assessment 2

Glucose Markers

• Fasting blood glucose should be measured at the same intervals as lipid screening (every 5 years, or every 2 years if risk factors present) 1, 3

• Hemoglobin A1c should begin at age 40-70 years in adults with BMI ≥25 kg/m², or age 45 in those without risk factors 2

Renal Function Markers

• Serum creatinine with eGFR calculation is essential, as eGFR <60 mL/min/1.73 m² indicates chronic kidney disease and significantly elevated cardiovascular risk 3

• Urinalysis with microalbuminuria assessment should be performed, particularly in patients with diabetes or hypertension 1, 3

Age-Specific Screening Initiation

High-Risk Patients (Start at Age 20)

Begin comprehensive lipid and glucose screening at age 20 if any of these risk factors are present: 1, 2, 4

• Family history of premature CVD (male first-degree relative <55 years; female first-degree relative <65 years)
• Diabetes mellitus
• Current cigarette smoking
• Hypertension (BP ≥140/90 mm Hg or on antihypertensive medication)
• Obesity

Average-Risk Men

• Ages 20-35 without risk factors: Routine lipid screening not recommended 1, 2
• Ages 35 and older: Strongly recommended to begin lipid screening 1

Average-Risk Women

• Ages 20-45 without risk factors: Routine lipid screening not recommended 1
• Ages 45 and older: Strongly recommended to begin lipid screening if at increased risk for CHD 1

All Adults Age 40-75

• Lipid testing is strongly recommended for comprehensive cardiovascular risk assessment 1, 2

Screening Intervals

• Every 5 years is the standard interval for lipid profiles in patients without risk factors 1, 2

• Every 2 years for patients with risk factors present or lipid levels close to treatment thresholds 1, 2

• More frequent testing (within 4-12 weeks) after initiating lipid-lowering therapy to assess response 4

Additional Risk Markers (Selective Use)

The following markers show promise for risk stratification in intermediate-risk patients only (10-year ASCVD risk 5-20%), but are not recommended for routine screening: 1, 5

High-Sensitivity C-Reactive Protein (hs-CRP)

• May provide additional risk stratification in intermediate-risk patients 1, 3
• Independently associated with incident CHD (HR 1.28) 5
• Net reclassification improvement of 0.079 for incident CHD 5

Apolipoprotein B (ApoB)

• Evaluated but not recommended for routine screening beyond standard lipid profile 1

Critical Caveat: Advanced lipoprotein testing beyond a standard fasting lipid profile is not recommended for cardiovascular risk assessment in asymptomatic adults (Class III: No Benefit recommendation) 2

Common Pitfalls to Avoid

• Never rely on a single lipid measurement for diagnosis or treatment decisions; always confirm abnormal results 2

• Do not screen all young adults regardless of risk factors, as this leads to unnecessary testing and cost 1, 2

• Do not order advanced lipoprotein panels routinely, as they do not improve risk assessment beyond standard lipid profiles 2

• Do not forget to integrate results into a global cardiovascular risk score that combines multiple risk factors, rather than treating lipid levels in isolation 2

Integration with Overall Risk Assessment

Once blood markers are obtained, they must be combined with: 1

• Age and sex
• Blood pressure measurements
• Smoking status
• Presence of diabetes
• Family history

These factors are used to calculate 10-year ASCVD risk, with patients having ≥20% risk or diabetes considered CHD risk equivalents requiring aggressive intervention 1