When to Test Lipoprotein(a) in Children
In children with a family history of premature cardiovascular disease or familial hypercholesterolemia, Lp(a) testing should be performed as early as age 2 years when obtaining the initial lipid profile, and repeated at puberty (≥12 years) regardless of previous results. 1, 2
Primary Screening Recommendations
High-Risk Children (Family History Present)
Measure Lp(a) as early as age 2 years in children with a family history of either:
- Early CVD (MI, documented angina, or atherosclerosis by angiography in parents, siblings, grandparents, aunts, or uncles: <55 years for men, <65 years for women) 3
- Significant hypercholesterolemia (total cholesterol ≥240 mg/dL, LDL-C ≥190 mg/dL, non-HDL-C ≥220 mg/dL, or known primary hypercholesterolemia) 3
Repeat Lp(a) testing at puberty (≥12 years) even if previous values were normal, as this represents a critical period for lipid reassessment 2
Rationale for Early Testing
- Lp(a) levels are genetically determined and reach adult levels by age 2 years, remaining stable throughout life 4
- Lp(a) >30 mg/dL in children with FH is independently associated with positive family history of premature CVD (69.9% vs 36.7% in those with Lp(a) ≤30 mg/dL, p<0.0001) 5
- Markedly elevated Lp(a) (>75 nmol/L) combined with elevated LDL-C increases MI risk 10-fold or higher 1
Universal Screening Considerations
While not yet standard practice, emerging evidence supports broader screening:
- Consider Lp(a) measurement during routine universal lipid screening at ages 9-11 years or 17-21 years 4
- This approach would identify at-risk youth and enable family cascade screening for early intervention in affected relatives 4
- Single lifetime measurement is sufficient given the genetic stability of Lp(a) levels 4
Clinical Thresholds and Actions
Risk Stratification
- Lp(a) >30 mg/dL is associated with increased cardiovascular risk and warrants intensive lifestyle modifications 5, 6
- Lp(a) >75 nmol/L represents markedly elevated risk requiring aggressive management 1
When Lp(a) is Elevated
- Intensify LDL-C reduction goals to approximately 50% from baseline, with target <100 mg/dL 1
- Consider statin therapy at age ≥10 years if LDL-C remains ≥160 mg/dL after lifestyle modification, particularly with elevated Lp(a) 1
- Perform cascade screening of first-, second-, and third-degree biological relatives 3, 2
Special Populations
African-American Children
- Higher prevalence of elevated Lp(a) in African-American children (19.3% vs 2.1% in other ethnicities with high Lp(a)) 6
- Maintain heightened clinical suspicion in this population 6
Children with Familial Hypercholesterolemia
- Lp(a) screening is particularly important as it enhances risk assessment beyond LDL-C alone 5
- Children with FH and Lp(a) >30 mg/dL have significantly higher rates of family history of premature CVD 5
Common Pitfalls to Avoid
- Do not delay Lp(a) testing until adolescence in high-risk children—levels are stable from age 2 and early identification enables family screening 4
- Do not assume normal childhood Lp(a) remains normal through puberty—repeat testing at puberty is recommended 2
- Do not rely solely on family history reporting—it has modest predictive value (relative risk 1.6) compared to direct Lp(a) measurement 7
- Do not overlook Lp(a) when LDL-C appears controlled—Lp(a) confers independent cardiovascular risk 1, 5