Classification of Hyperlipidemias

For the purposes of diagnosis and treatment the most convenient classification is that which is based on the type of lipid abnormality (cholesterol, TG, or both).

1. Primary hyperlipidaemias

Hypercholesterolaemia

• Familial
• Polygenic

Hypertriglyceridaemia

• Familial lipoprotein lipase (LPL) deficiency
• Familial apolipoprotein C-II deficiency
• Familial hypertriglyceridaemia                        

Combined hypertriglyceridaemia and hypercholesterolaemia

• Familial combined hyperlipidaemia
• Familial type 3 hyperlipoproteinaemia

2. Secondary hyperlipidaemias 

Hypercholesterolaemia

• Hypothyroidism
• Obstructive jaundice
• Acute porphyria
• Growth hormone deficiency
• Drugs: corticosteroids

Hypertriglyceridaemia

• Diabetes mellitus (DM)
• Alcoholism
• Lipodystrophies
• Renal failure
• Oestrogens (pregnancy,oral contraceptives)
• Glycogen storage disease
• Systemic lupus   erythematosis (SLE)
• Obesity
• Severe stress
• Thiazides

Combined hypertriglyceridaemia and hypercholesterolaemia

• Nephrotic syndrome
• Myelomatosis
• Diabetes mellitus (DM)
• Renal failure

Fredrickson Classification

WHO (Fredrickson) classification of hyperlipidaemias, based on the electrophoeretic pattern of lipoproteins is as follows:

Types /Classification	Seen on Electrophoresis	Which Lipoprotein are increased	Which Lipids increased
I	Increased chylomicrons zone	Chylomicrons	Triglyceride
IIa	Increased beta-lipoproteins zone	LDL-c	Cholesterol
IIb	Increased pre-beta and beta lipoproteins zone	VLDL and IDL-c	Cholesterol and Triglyceride
III	Beta band is broad in beta band zone	IDL-c	Cholesterol and Triglyceride
IV	Increased pre-beta lipoprotein zone	VLDL	Triglyceride
V	Increased pre-beta lipoprotein zone and chylomicrons zone	VLDL and chylomicrons	Cholesterol and Triglyceride