Hyperlipidemia

Question 1

Definition of hyperlipidemia

Answer 1

LDL, total cholesterol, triglyceride, or lipoprotein level greater than 90th percentile
OR
HDL level less than 10th percentile

Question 2

Benefit of HDL

Answer 2

regulates cholesterol levels to prevent atherosclerotic vascular disease

Question 3

Primary hyperlipidemia

Answer 3

Familial - due to genetic disorder

Question 4

Secondary hyperlipidemia

Answer 4

Acquired- originates from underlying factor such as diet, medication, hypothyroidism, diabetes

Question 5

What is cholesterol?

Answer 5

circulating fatty substance that causes artherosclerosis

Question 6

How much cholesterol should be obtained exogenously and endogenously?

Answer 6

exogenous: 300-700 mg per day
endogenous (made by liver): 800-1200 mg per day

Question 7

What is hypercolesterolemia?

Answer 7

elevated LDL

Question 8

When does atherososclerosis become symptomatic?

Answer 8

Until the plaque reaches 70-80% of the vessels diameter

Question 9

How does atherosclerosis develop?

Answer 9

Endothelial damage occurs from the loss of nitric oxide in the endothelium, which increases inflammation at the site and allows lipids to accumulate.

Lipids are engulfed by macrophages and encapsulated by smooth muscle, creating a fibrotic plaque

Question 10

What are foam cells?

Answer 10

Foam cells result from the engulfment of lipids by macrophages. Cholesterol builds up in foam cells and causes cell death and necrotic tissue.

Foam cells are encapsulated and protected by muscle, making a plaque

Question 11

What are the 2 ways that plaques evolve?

Answer 11

1. slowm chronic plaque buildup that eventually leads to stenosis
2. Acute onset of rapid obstruction secondary to plaque rupture and thrombosis

Question 12

What kinds of patient information is usesful in assessing hyperlipidemia risk?

Answer 12

• family hx of cardiovascular disease and hyperlipidemia
• diet and exercise
• tobacco and alcohol
• CAD, PAD, or angina history
• other med hx indicating increased risk

Question 13

What is a lipid profile?

Answer 13

LDL, HDL, tryglycerides, and total cholesterol

Question 14

Treatment course for hyperlipidemia

Answer 14

Exercise 30 min daily 5-6X per week
Low-saturated fat, low carb diet
Statins: pravastatin (40 mg), lovastatin (20-40 mg), atorvastatin (10 mg), rosuvastatin (10 mg)

Question 15

How does HDL prevent atherosclerosis?

Answer 15

• transports cholesterol from walls of arteries to the liver
• antioxidant and anti-inflammatory - induces release of nitric oxide

Question 16

Lipoproteins

Answer 16

Lipids are encapuslated by proteins because they are insoluble in plasma

1. chylomicrons
2. very-low-density lipoproteins
3. intermediate-density lipoproteins
4. low-density lipoproteins
5. high-density lipoproteins

Question 17

Which type of lipoprotein carries the most cholesterol?

Answer 17

LDL

Question 18

Which lipoprotein carries the most triglycerides?

Answer 18

VLDLs (mostly tri with a little cholesterol and proteins)

Question 19

What are the 2 pathways of production and transport of lipoproteins?

Answer 19

1. Exogenous intestinal pathway
2. Endogenous hepatic pathway

Question 20

Exogenous pathway of lipoprotein transport

Answer 20

1. Chylomicrons are made in wall of small intestine
2. Chylomicrons transport triglycerides transport dietary triglycerides to peripheral tissues (especially fat and skeletal muscle)
3. Remnant chylomicron particles contain dietary cholesterol and are taken up by liver
4. Cholesterol is used to make VLDL or is excreted in bile

Question 21

Endogenous pathway of lipoprotein transport

Answer 21

1. the liver forms triglycerides, which is used to form VLDL
2. VLDL carries trigylcerides to fat and muscle cells, where they are removed for energy and storage
3. Resulting IDL (less tri and more cholesterol) go to liver
4. IDL recycled to form VLDL with additional triglycerides or converted to LDL, which transfer cholesterol to HDL at peripheral tissues to be taken to liver for removal in the bile

Question 22

Where does LDL go after it is made?

Answer 22

60% goes to liver
40% goes to extrahapatic tissues such as adrenal cortex and gonads (use cholesterol in cell membranes and steroid hormones)

Question 23

How is HDL made?

Answer 23

1. direct secretion by intestine and liver

Question 24

3 stages of atherosclerosis

Answer 24

1. fatty streaks
2. fibrous atheromatous plaques
3. complicated lesions

Question 25

What is complicated atherosclerotic lesions?

Answer 25

Plaque breaks open and produces hemorrhage, ulceration and scar tissue due to slowing and turbulence of blood flow