Laboratory Assessment

Question 1

Criteria for biomarkers to meet (4)

Answer 1

1. Unique measurement
2. Unique treatment
3. Improves clinical outcomes
4. Cost effective

Question 2

ApoB

Answer 2

• Proxy for non-HDL cholesterol
• B100 marker for whats produced in liver
• Strong correlation of ApoB with LDL particle #

Treatment improves clinical outcomes (lowering ApoB is similar to lowering LDL)

Question 3

ApoA1

Answer 3

Correlated with HDL particle #

Question 4

LDL particle size:
The more cholesterol there is, the (larger/smaller) the particle size?

Answer 4

Larger. Cholesterol does not stack as well as triglycerides.

Question 5

Lipoprotein a/Lp(a)

Answer 5

Acts as an acute phase reactant and marker of inflammation. Seems to be a genetic marker of ASCVD risk in young males.

Unique measurement
Some unique treatments

Question 6

(Increased/Decreased) homocysteine levels associated with genetic defects have been correlated with increased risk for ASCVD.

Answer 6

Increased

Question 7

20% risk reduction of ischemic heart disease and stroke with a 25% reduction in __________ levels.

Answer 7

Homocysteine

Question 8

(T or F) CRP and Fibrinogen are both acute phase reactants that indicate inflammation

Answer 8

True

Question 9

(T or F) CRP and Fibrinogen meet 4/4 biomarkers

Answer 9

True

● Unique measurement (increased CRP increases Framingham risk)
● Treatment is unique (treatments include high antioxidant diet)
● Treatment does improve outcomes (there is regression of atheromas as demonstrated in the REVERSAL trial with statins and there is a reduction in events with statin therapy)
● May be cost effective

Question 10

Lp-PLA2 are secreted by _________ (3 cell types) and are transported by ______________.

Answer 10

Macrophages, T cells, mast cells

Lipoproteins (mainly LDL)

Question 11

How is oxidized LDL formed?

Answer 11

Formed from the peroxidation of polyunsaturated fatty acids in LDL

Question 12

Pomegranate juice reduced oxidized LDL levels by __% at ___ oz daily due to ellagic acid in pom juice that is antioxidant

Answer 12

90%

2oz

Question 13

GGT activity increases when there is an increased demand for reduced _______.

Answer 13

Glutathione

Question 14

Why should we be cautious of labs that assess beta carotene when using it as a biomarker to assess risk for ASCVD?

Answer 14

Beta carotene is not highly correlated with CVD.

Question 15

What are we assessing when we measure carotenoids in patients?

Answer 15

Fruit and vegetable intake, fat absorption rate. Lutein depletion within LDL before LDL is oxidized.

Question 16

What is the problem with measuring serum magnesium levels?

Answer 16

Serum magnesium is tightly regulated, not helpful to measure

Question 17

What is the best method to test for magnesium levels?

Answer 17

Timed urine test

Question 18

What might be the best way to assess magnesium levels?

Answer 18

Food frequency questionnaire

Question 19

How might vitamin D insufficiency be associated with increased risk for cardiovascular disease?

Answer 19

Insufficiency linked with increased inflammatory markers (Tnf-alpha, serum amyloid a, IL-6, IL-10).

Question 20

What were the outcomes of the VITAL study? (Vit D)

Answer 20

No measure of risk of major cardiovascular events with 2000 IUs of D3 per day.

Question 21

What is the omega-3 index? Is it a valid test?

Answer 21

Reports percent EPA and DHA of RBCs, seems to be well validated and corresponds with dietary intake.

Question 22

What about measuring serum free fatty acids? Is it a valid test?

Answer 22

Serum free fatty acids (including w-3) available from most routine clinical labs. Clinical utility unknown.

Question 23

Evidence shows there is a _______ depletion within LDL before LDL is oxidized

Answer 23

Lutein