What You Should Know about High / Very High Lipoprotein (a) 

Lipoprotein(a), AKA "Lp(a)".png

Lipoprotein(a), also known as Lp(a) or “LP little a”, is a type of low-density lipoprotein (LDL) particle with a unique extra protein on the outside surface, apolipoprotein (a). 

Why does measuring Lp(a) matter for cardiovascular and cardiometabolic risk? Elevated Lp(a) is an independent causal risk factor for ASCVD, often underrecognized because it isn’t modified by lifestyle or statins.

📚 Learn more about High ApoB and Lp(a) testing for holistic risk assessment

Lp(a) particles have properties that often indicate a greater cardiovascular risk than other LDL particles.1 Elevated Lp(a) is is a fairly common inherited disorder that affects an estimated 1 in 5 individuals.2 Affected individuals have high Lp(a) levels from birth which increases risk of plaque formation and cardiovascular events beyond risk due to other factors such as high blood pressure (hypertension) or sedentary lifestyle.1 A simple blood test can measure your Lp(a) level; however, it is not included in standard cholesterol or lipid panels.

Lp(a) are reported in different units, either mg/dL or nmol/L (the preferred unit of measure). Lp(a) values are categorized in 3 ranges:

  • Normal Lp(a) level: < 30 mg/dL, or < 75 nmol/L
  • Elevated Lp(a) level: 30-50 mg/dL, or 75-125 nmol/L3
  • Very High Lp(a) level: > 50 mg/dL, or > 125 nmol/L4

An increased Lp(a) value is common in several clinical situations.3

  • Individuals with a family history of premature cardiovascular events (before age 55 in men, or age 65 in women).

  • Individuals diagnosed with cardiovascular disease, or who experience a cardiovascular event such as a heart attack or stroke, without other known risk factors.

  • Individuals with familial hypercholesterolemia (FH).

Very High Lp(a) is considered a “risk enhancing factor” when determining an individual’s cardiovascular risk.4 Although less severe, elevated Lp(a) (values 75 - 125 nmol/L) can also worsen cardiovascular risk.1,3 Your healthcare provider may consider more aggressive treatment to lower LDL levels when he or she identifies you as having elevated Lp(a) levels.3

Occasionally, elevated Lp(a) can be associated with certain medical conditions including hypothyroidism (low thyroid function), kidney disease, or eating increased amounts of trans fats. You should discuss these possibilities with your health care team.

As with other inherited disorders, when someone is diagnosed with elevated Lp(a) it is important to consider testing other relatives such as parents, siblings, and children.

📌 “More to Read” about Lp(a)

Frequently Asked Questions about Lp(a)

  • Lp(a) is a cholesterol-carrying particle like LDL, but it has an added apolipoprotein(a) component. This makes it more atherogenic and pro-inflammatory than LDL alone. Importantly, standard cholesterol panels do not measure Lp(a).

  • Unlike ApoB and LDL cholesterol, diet and exercise have little to no effect on Lp(a) levels. That’s why knowing your Lp(a) is critical to measure as it often requires specific therapeutic considerations and affects overall cardiovascular risk interventions.

  • Guidelines recommend testing if you have a strong family history of premature heart disease, high LDL despite treatment, or unexplained cardiovascular events. Many experts suggest at least one lifetime measurement for all adults. Almost everyone should have their Lp(a) tested at least once since it is not expensive or invasive.

  • Yes. Elevated Lp(a) may influence how aggressively your clinician manages your other risk factors like ApoB, blood pressure, and glucose control. New therapies targeting Lp(a) are also in development but not available (yet).

  • Routine cholesterol panels don’t include Lp(a). Historically, the test wasn’t widely available and wasn’t prioritized in treatment guidelines since there is no specific treatment for high Lp(a). Now Lp(a) testing is readily available and inexpensive and knowing Lp(a) is a critical piece of personalized risk detection.

Interested in getting your Lp(a) lab test or your complete personalized Cardiometabolic Risk Assessment?

Additional Reading if you want to learn more about this important, but often not-tested Lipoprotein(a) biomarker:

References

  1. Tsimikas S, Hall JL. Lipoprotein(a) as a potential causal genetic risk factor of cardiovascular disease: a rationale for increased efforts to understand its pathophysiology and develop targeted therapies. J Am Coll Cardiol 2012;60:716-21.

  2. Varvel S, McConnell JP, Tsimikas S. Prevalence of Elevated Lp(a) Mass Levels and Patient Thresholds in 532 359 Patients in the United States. Arterioscler Thromb Vasc Biol 2016;36:2239-45.

  3. Tsimikas S, Fazio S, Ferdinand KC, et al. NHLBI Working Group Recommendations to Reduce Lipoprotein(a)-Mediated Risk of Cardiovascular Disease and Aortic Stenosis. Journal of the American College of Cardiology 2018;71:177-92.

  4. Grundy SM, Stone NJ, Bailey AL, et al. 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the Management of Blood Cholesterol: Executive Summary. A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines 2019;73:3168-209.