Disorder | Estimated prevalence | Characteristic lipid levels* | Clinical features | Confirmatory studies |
In adults | In children |
Heterozygous familial hypercholesterolemia | 1/200 to 1/300 | - Elevated TC and LDL-C
- LDL-C 190 to 450 mg/dL¶
- TG usually normal
| - Tendon or tuberous xanthomata
- Xanthelasmas
- Corneal arcus
- Premature CHD
| - Subclinical atherosclerosis
| - Exclusion of secondary disorders of cholesterol
|
Homozygous familial hypercholesterolemia | 1/1,000,000 | - Markedly elevated TC and LDL-C
- Untreated LDL-C >500 mg/dL
- TG usually normal
| - Extensive xanthomata
- Severe and progressive atherosclerotic cardiovascular disease
| - Cutaneous or tendon xanthomata often in the first year of life
- Premature CHD occurs in childhood if untreated
| - Genetic testing for mutations in the LDLR, APOB, and PCSK9 genes
|
FCHL | 1 to 2% | - Phenotypically heterogeneous
- Elevated TC and/or TG
- LDL-C/APOB ratio <1.2
| - Xanthelasma
- Corneal arcus
- Premature CHD
| - Clinical manifestations are typically not seen during childhood
| - Similar lipid profile in one first- or two second-degree relatives
|
Familial hyperapobetalipoproteinemia | <1% Likely a variant of FCHL | - APOB >135 mg/dL
- LDL-C <160 mg/dL
- LDL-C/APOB ratio <1.2
| - Xanthelasma
- Premature CHD
- Obesity
| - Clinical manifestations other than obesity are typically not seen during childhood
| - Similar lipid profile in at least two first- or second-degree relatives
|
Polygenic hypercholesterolemia | >25% | - Elevated TC and LDL-C
- TG usually normal
- LDL-C 130-250 mg/dL
| - Premature CHD
- Tendon xanthomata are not seen
| - Clinical manifestations are typically not seen during childhood
| |
Familial dysbetalipoproteinemia | 1/5000 | - Elevated TC and TG
- VLDL/TG ratio >0.3
| - Tuboeruptive xanthomata
- Xanthomata of the palmar creases
- Premature CHD
| - Clinical manifestations are typically not seen during childhood
| |