What You Need to Know About High / Very High LDL Cholesterol Levels 

Many factors can influence cholesterol and triglyceride levels. Individuals with high LDL cholesterol values should be evaluated for potential secondary causes, including hypothyroidism, diabetes, liver disease, chronic kidney disease, and medications such as estrogens, progestins, anabolic steroids/androgens, corticosteroids, cyclosporine, retinoids, certain antipsychotic medications, and antiretrovirals (particularly protease inhibitors).¹

Additionally, genetic abnormalities can cause significant cholesterol elevations. More commonly, several genes cluster together to increase LDL-C. This is called “polygenic” high cholesterol.²

In many cases, a single dominant gene runs in families and causes very high LDL-C levels from birth. This is known as familial hypercholesterolemia, or “FH”.

• FH is a common, life-threatening genetic disorder present in 1 in 250 people of all races and ethnicities.³

• If one parent carries an FH gene, each child born has a 50% chance of inheriting FH.

• Because FH causes high LDL levels from birth, people with FH have a 5-7 fold higher risk of heart attack versus someone without FH at the same LDL level.⁴

• If left untreated, men have a 50% risk of having a heart attack by age 50. Untreated women have a 30% risk of having a heart attack by age 60.^4,5

• FH related cardiovascular risk can be reduced.⁶ When LDL is lowered and maintainedat appropriate levels, FH patients have significantly less cardiovascular risk over time.

Most commonly, FH is diagnosed clinically using a validated scoring system based on the following factors in the patient and close relatives (mother, father, siblings, and children).⁴

• LDL-C levels > 190 mg/dL in adults or > 160 mg/dL in children < 18 years of age

• History of premature vascular disease (men < 55 years old, women < 65 years old)

• Selected physical manifestations including:

  Presence of Achilles tendon thickening,

• Xanthomas (cholesterol deposits in skin or tendons), or

• Corneal Arcus (white ring around the colored part of the eye before the age of 45)

• Confirmatory genetic testing (if available)

Scoring systems used identify FH include the Dutch Lipid Clinic Network (DLCN) score, the Simone-Broom score, and the American Heart Association score.

Overall, the more criteria present, the greater the clinical likelihood of FH.⁷

The DLCN score classifies an individual’s likelihood of FH as follows:⁷

• Definite FH: >8 Points

• Probable FH: 6 to 7 Points

• Possible FH: 3 to 5 Points

• Unlikely FH: < 3 Points

• For more information visit The FH Foundation.