Is it recommended to order lipoprotein(a) (Lp(a)) testing for a 17-year-old asymptomatic patient?

Lipoprotein(a) Testing in a 17-Year-Old Patient

Lipoprotein(a) testing is not recommended for routine cardiovascular risk assessment in asymptomatic 17-year-old patients. 1

Rationale for Not Testing Lp(a) in Asymptomatic Adolescents

The American College of Cardiology/American Heart Association guidelines specifically address lipid testing in adolescents and do not recommend measurement of lipoproteins, including Lp(a), beyond a standard fasting lipid profile for cardiovascular risk assessment in asymptomatic individuals 1. This recommendation is classified as Class III: No Benefit, indicating that the procedure/test is not helpful and may be harmful.

Appropriate Lipid Testing for 17-Year-Olds

For a 17-year-old patient, the appropriate approach to lipid assessment includes:

• Universal lipid screening once between ages 17-21 years 1, 2
• The recommended screening method is either:
  • Non-fasting lipid profile (calculating non-HDL cholesterol)
  • OR a fasting lipid panel 1

If the initial screening shows abnormal results (for a 17-19 year old):

• Non-HDL cholesterol ≥145 mg/dL and HDL cholesterol <40 mg/dL, OR
• LDL cholesterol ≥130 mg/dL, non-HDL cholesterol ≥145 mg/dL, HDL cholesterol <40 mg/dL, or triglycerides ≥130 mg/dL

Then a repeat fasting lipid profile should be performed and the results averaged 1.

Exceptions: When Lp(a) Testing May Be Considered

While routine Lp(a) testing is not recommended for asymptomatic 17-year-olds, there are specific circumstances where it might be appropriate:

1. Family history of premature cardiovascular disease (MI, documented angina, or atherosclerosis in parents, siblings, grandparents, aunts, or uncles <55 years for men, <65 years for women) 1

2. Family history of significant hypercholesterolemia or known familial hypercholesterolemia (FH) 1

3. Personal history of other cardiovascular risk factors such as diabetes, hypertension, BMI ≥95th percentile, or cigarette smoking 1

4. Known genetic dyslipidemia in the family 1

Clinical Implications of Lp(a) Testing

If Lp(a) testing is performed and elevated levels (>50 mg/dL) are found, this would primarily impact management by:

1. Potentially reclassifying the patient into a higher risk category 1
2. Leading to more intensive management of treatable risk factors, especially LDL cholesterol 1
3. Prompting cascade screening of family members 3

Key Considerations

• Lp(a) levels are genetically determined and remain relatively stable throughout life, reaching peak levels by age 5 4
• A single lifetime measurement is generally sufficient if normal 3
• There are currently limited specific therapies targeted at lowering Lp(a) in clinical practice 5
• The focus of management for elevated Lp(a) remains aggressive treatment of modifiable cardiovascular risk factors 1

Conclusion

For a typical 17-year-old without specific risk factors, standard lipid screening as recommended by guidelines is appropriate, without the addition of Lp(a) testing. The evidence does not support routine Lp(a) testing in this age group for improving morbidity, mortality, or quality of life outcomes.