Cardiovascular Disease (Traditional Risk Markers) - Risk Markers - CVD (Traditional)

Diagnosis

Indications for Testing

• ATP III guidelines
  • Adults >20 years – obtain baseline lipid testing and repeat testing every 5 years

Criteria for Diagnosis

• Identify risk factors present for CVD 
  • Elevated LDL-C – current gold standard diagnostic risk marker
  • Tobacco use
  • Hypertension – blood pressure >140/90 mmHg or on medication for hypertension
  • Low HDL-C – <40 mg/dL
    • HDL-C ≥60 mg/dL is considered beneficial and removes one risk factor from the total count
  • Family history of early CVD – <55 years in first-degree male relative or <65 years in first-degree female relative
  • Increased age – men ≥45 years; women ≥55 years
• If >2 risk factors are present, assess Framingham criteria projections for 10-year CVD risk
  • A 20% risk is considered equivalent to one CVD risk factor
  • Refer to the Framingham criteria-based National Cholesterol Education Program calculator to estimate the patient's 10-year risk of developing CVD 
    • This simplified calculator provides quick assessment and may overestimate CVD risk 
    • See the NIH-NACEP ATP III Guidelines At-A-Glance Quick Desk Reference for further guideline information
• Treatment goals are determined by final risk category

  Source	Risk	Target LDL-C
  American Diabetes Association (ADA)/ American College of Cardiology (ACC) Consensus (2008)	Highest Known CVD DM plus ≥1 risk factor(s) for CVD	<70 mg/dL
  	High ≥2 risk factors for CVD DM (no other CVD risk factors)	<100 mg/dL
  ADA Practice  Guidelines (2012)	DM	<100 mg/dL
  	Known CVD plus DM	<70 mg/dL
  ATP III  Guidelines (2004)	Very high Known CVD plus DM or metabolic syndrome	<70 mg/dL
  	High Known CVD DM CVD risk factor	<100 mg/dL
  	Intermediate	<130 mg/dL
  	Low	<160 mg/dL

  • Initiate lifestyle modifications and/or drug therapy to reduce LDL-C to target concentrations
  • High TG (>150 mg/dL)
    • Lifestyle modifications
    • If TG ≥200 mg/dL, non-HDL-C target is set 30 mg/dL higher than LDL-C target

Laboratory Testing 

• Determine lipoprotein concentrations using fasting lipid testing 
  • LDL-C, HDL-C and TG are the minimum recommendation
  • No consensus guidelines support use of LDL-C subclasses

Screening

Monitoring

Clinical Background

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in the U.S.

Epidemiology

• Prevalence – 1.2 million myocardial infarctions annually in U.S.
• Age – risk increases with age
• Sex – M>F

Risk Factors for CVD

• Elevated low-density lipoprotein cholesterol (LDL-C) – ≥130 mg/dL
  • For detection, evaluation, and treatment of high blood cholesterol in adults, refer to National Heart, Lung and Blood Institute Guidelines
• Tobacco smoking
• Hypertension – 140/90 mmHg or on medication for hypertension
• Low levels of high-density lipoprotein cholesterol (HDL-C) – <40 mg/dL
• Family history of early CVD – <55 years in first-degree male relative or <65 years in first-degree female relative
• Increasing age – men ≥45 years; women ≥55 years
• Diabetes mellitus (DM)

Basis of Risk Assessment

• Statins shown to reduce LDL-C concentrations and to reduce cardiovascular mortality in numerous trials
  • Identifying patients who will benefit from drug therapy is important for early prevention and intervention
• Adult Treatment Panel (ATP) III guidelines (Framingham Heart Study)
  • Identify patients at risk for development of CVD
  • Develop plan of action for at-risk patients, including target goals for LDL-C and triglycerides (TG)

Pediatrics

Clinical Background

Epidemiology

• Prevalence – in last 10 years, increasing prevalence of hyperlipidemia in children, which mirrors increasing level of obesity
  • ~20% of youth 12-19 years have abnormal cholesterol values

Diagnosis

Indications for Testing

• Obesity
• Family history of early hyperlipidemia
• Diabetes mellitus

Laboratory Testing

• Lipid profile

  	Cholesterol	LDL
  Acceptable	<170 mg/dL	<110 mg/dL
  Borderline	170-199 mg/dL	110-129 mg/dL
  Elevated	≥200 mg/dL	≥130 mg/dL

Screening

• U.S. Preventive Services Task Force (USPSTF, 2007) – insufficient evidence to recommend screening
• American Academy of Pediatrics (2008) – screen children and adults (fasting lipid profile)
  • Recommended if family history of CVD or other CVD risk factors 
  • No definitive data exists to show which cholesterol level predicts risk of adult CVD
  • If levels acceptable, repeat every 3-5 years

Indications for Laboratory Testing

• Tests generally appear in the order most useful for common clinical situations
• Click on number for test-specific information in the ARUP Laboratory Test Directory

Click the plus sign to expand the table of additional tests.

Test Name and Number	Comments
Triglycerides, Serum or Plasma 0020040 Method: Quantitative Enzymatic
LDL Subclasses 0050021 Method: Quantitative Electrophoresis	Not validated to assess CVD risk
HDL Cholesterol 0020053 Method: Detergent Solubilization/Enzymatic
Cholesterol, Serum or Plasma 0020031 Method: Quantitative Enzymatic
Glucose Tolerance Test 0020542 Method: Quantitative Enzymatic	Diagnose DM and establish criteria for metabolic syndrome Patient must be fasting Components include fasting glucose and 2-hr glucose
Apolipoprotein B 0050029 Method: Quantitative Nephelometry