Lipids & Lipoproteins Flashcards
1
Q
A genetic problem causing decreased elimination of VLDL
A
Hyperlipoproteinemia IV (Familial hypertriglyceridemia)
2
Q
A delay in removal of LDL due to a lack of high affinity LDL-Apo B receptors in peripheral tissues
A
Hyperlipoproteinemia IIa (Familial hypercholesterolemia)
3
Q
In the more common form of HLP IIa the people tend to live into their 50’s or so, while in the more rare form they usually don’t make it to 20. ____ occurs in 1/500, while _____ occurs in 1/1 million
A
Heterozygous, homozygous (autosomal dominant)
4
Q
SSx’s of which type of hyperlipoproteinemia?
- Xanthelasmas and xanthomas
- Arcus juvenilis (premature white/gray ring in corneal margin)
- arterial bruits
- claudication (pain, usually in legs, caused by too little blood flow (PAD))
- accelerated atherosclerosis
A
Type IIa
5
Q
Name the 4 SSx’s of HLP IV
A
- Obesity
- Lipemia retinalis (abnormal appearance of retinal arteries and veins)
- Atherosclerosis
- Hepatosplenomegaly
6
Q
Which type of HLP results in increased triglycerides and decreased HDL, along with normal cholesterol and LDL levels?
A
Type IV
7
Q
What are the major lab findings in HLP IIa?
A
- Increased serum cholesterol
- Increased LDL (“bad guy”)
- TG normal
8
Q
In the _____ form of HLP IIa, serum cholesterol is usually increased to levels of 250-500mg/dL, while the _____ form has levels increased to 500-1,200mg/dL
A
Heterozygous, homozygous
9
Q
The protein fraction of lipoproteins is composed predominantly of several polypeptides called _____
A
Apoproteins
10
Q
____ are considered to be an accurate predictor of CHD
A
Lipoproteins
11
Q
___ are proteins in the blood whose main purpose is to transport lipids, triglycerides, and other insoluble fats.
A
Lipoproteins
12
Q
What are the four categories of lipoproteins?
A
- Chylomicrons
- HDL
- LDL
- VLDL
13
Q
Which two lipoproteins are mainly triglycerides?
A
- Chylomicrons
2. VLDLs
14
Q
Which lipoprotein is considered the “bad guy” because it is mainly composed of cholesterol?
A
LDLs
15
Q
HDLs are predominantly composed of _____
A
Protein
16
Q
___ are primarily triglyceride transport vehicles
A
Chylomicrons
17
Q
Where do chylomicrons originate?
A
Intestinal epithelial cells
18
Q
The liver clears chylomicrons from the blood, incorporates the triglycerides into lipoproteins, and releases them back into the bloodstream as ____
A
VLDLs
19
Q
The alpha-lipoprotein
A
HDL
20
Q
This lipoprotein is made in the liver and carries cholesterol in the bloodstream from the tissues TO the liver (reverse cholesterol transport)
A
HDLs
21
Q
The ___/TC ratio should be at least 1:5, with an ideal ratio being 1:3.
A
HDL
22
Q
HDLs are composed of ___% protein, 1-5% TG, ___% cholesterol, and 30% phospholipid
A
50%, 15%
23
Q
Reference values for HDL? Both sexes.
A
Men: >40mg/dL
Women: >46mg/dL
24
Q
What level of HDLs is considered protective against heart disease?
A
> /=60mg/dL
25
Increased HDLs is called?
Hyperalphalipoproteinemia
26
High HDLs is considered a good thing, but in ____ disease they will also be increased.
Chronic liver disease
27
Uncontrolled diabetes, hepatocellular disease, chronic renal failure, nephrosis, uremia, cholestasis are all complications that would ____ HDL levels
Decrease (i.e. bad.)
28
What type of things can increase HDL levels?
Exercise, weight loss, estrogens, insulin, hypothyroidism
29
The beta-lipoprotein
LDL
30
____ carry cholesterol TO the peripheral tissues and their levels are directly proportional to the risk of CHD
LDLs
31
LDLs are composed of ___% cholesterol
45%
32
Friedewald Equation: ___=TC-(HDL + TG/5)
LDL
33
The formula for calculating LDLs is only valid for TG levels
400
34
Reference range for LDLs? (Normal)
<130mg/dL
35
Optimal levels of LDLs?
<100mg/dL
36
LDL levels >/=___ are considered very high
190mg/dL
37
Which type of hyperlipoproteinemia results in increased LDLs?
HLP IIa (familial hypercholesterolemia)
38
Hyperthyroidism and chronic anemia may cause ___ levels of LDL
Decreased
39
The primary carriers of transporting triglycerides from the liver to other organs?
VLDLs
40
VLDL levels in excess of __-__% are associated with an increased risk of coronary disease.
25-50%
41
The target number for Non-HDL cholesterol is __mg/dL HIGHER than LDLc
30
42
Formula for Non-HDLc?
=TC-HDLc
43
The lipoproteins (HDL, LDL, VLDL) test is used to assess the risk of ____
Coronary artery disease
44
How long should a patient fast before a lipid panel?
12-14 hours
45
Cholesterol is a ____, carried in the bloodstream as a lipoprotein.
Steroid
46
The liver can produce ___g/day of cholesterol, while all other tissues can produce .5 g/day combined.
1.5
47
Circulating cholesterol can be eliminated through conversion by the ___ to salts of the bile acids
Liver
48
Most of the cholesterol we eat comes from what food source?
Animal origin
49
Disease of what organ would definitely alter cholesterol levels?
Liver
50
Cholesterol levels tend to gradually increase in men til the age of ___ and women to the age of ___, when they tend to plateau
50, 70
51
Anabolic steroids and oral contraceptives may ___ the level of total cholesterol
Increase
52
Normal desirable level of TC in adults?
125-200 mg/dL
53
Does a patient need to fast for a total cholesterol test?
NO
54
Total cholesterol >/= ___ is considered high and puts a person at twice the risk of CHD
240 mg/dL
55
Name the high end and low end TC levels which are considered to be red flags:
>400 mg/dL
| <90 mg/dL
56
Give three reasons for TC levels below 90 mg/dL
1. Liver disease
2. Hyperthyroidism
3. Anemia
57
An ACUTE biliary obstruction could increase TC levels to ___-___ mg/dL, while a CHRONIC obstruction could increase it to ___-___ mg/dL
400-500, 700-800
58
What are the “3 M’s” that would decrease TC levels?
1. Malabsorption
2. Malnutrition (vegans)
3. Malignancy (cancer)
59
Things like obesity, smoking, alcohol use, and a high saturated fat diet would ____ TC levels
Increase
60
Tell me if the following would increase or decrease TC levels:
- Biliary obstruction
- Pancreatic disease (such as DM)
- Hypothyroidism
- Pregnancy
- Glycogen storage disease (Von Gierke and Werner)
INCREASE
61
The 4 main causes of ___ TC levels:
1. Severe liver cell damage
2. Hyperthyroidism
3. Anemia
4. “3 M’s”
Low (decreased)
62
____ hepatitis will cause hypercholesterolemia due to the release from hepatocytes, while ___ hepatitis will eventually cause low levels of cholesterol due to decreased synthesis by damaged or necrotic cells.
Acute, chronic
63
So why would obstructed bile canaliculi and ducts cause a marked increase in TC levels?
Due to the inability to get rid of it as waste (decreased excretion into intestine)
64
What are the 3 diseases of the endocrine system that will cause increased levels of TC?
1. Hypothyroidism
2. Estrogen problem
3. Diabetes mellitus (pancreas)
65
Renal disease (also known as _____) would cause increased TC levels
Nephrotic syndrome
66
___ are a form of fat and major source on energy for the body. Most are stored in adipose tissue as glycerol. They are insoluble and must be transported in the blood via chylomicrons.
Triglycerides
67
There is roughly an inverse relationship between TG levels and ___ levels
HDL (Example: high TG, low HDL)
68
A common reason for high triglyceride levels? (Preparation issue)
Non-fasting
69
TG levels more than 1,000 mg/dL predispose to or often accompany acute _____
Pancreatitis
70
Normal triglyceride levels should be?
<150 mg/dL
71
TG levels of 150-250 mg/dL are due to?
Poor Diet/exercise
72
TG levels of 250-500 mg/dL are most likely due to?
HLP type IV (alcohol abuse can bring them up to 750)
73
TG levels >750 mg/dL is due to?
HLP types I or V
74
Critical values for TG level? (Low and high)
Low: <40 mg/dL
High: >400 mg/dL
75
List three steps to lower TG levels:
1. Avoid “white” foods (pasta, bread, potatoes, cookies)
2. Lose weight
3. Omega-3’s
76
Elevated levels of TG in the blood are associated with increased risk of?
1. Cardiovascular disease
| 2. Arteriosclerosis
77
List the 5 major risk factors associated with an increased risk of cardiovascular disease:
1. Smoking
2. Hypertension (>140/90mm Hg)
3. Low HDLc (<40mg/dL)
4. Family Hx of premature CHD
5. Age (men >45, women >55)
78
The primary target in hypercholesterolemia therapy is lowering LDLc, unless TG are >____
500 mg/dL
79
Which two lipoproteins are typically calculated (not measured) in a lipoprotein profile?
LDL and non-HDL
80
Other than the 5 major risk factors, others, and lipoprotein profile, cardiac risk can also be ascertained by determination of what ratio?
TC:HDL
81
TC:HDL for AVERAGE risk of CHD? (Both sexes)
```
Men= 1:5
Women= 1:4.5 (pre-menopause)
```
82
____ is an acute-phase reactant produced by hepatocytes and induced by the release of interleukin 1 and 6. It reflects activation of systemic inflammation. It is an independent risk factor for cardiovascular disease, stroke, and peripheral vascular disease (PVD).
High-sensitivity C-reactive protein (hs-CRP or cardiac CRP)
83
Normal range for hs-CRP?
0.3
84
Hyperlipemia
Increased triglycerides
85
Hyperlipidemia
Increase in any plasma lipid
86
Hyperlipoproteinemia
Increase in one or more lipoproteins (HDL, LDL, VLDL)
87
Familial hypercholesterolemia (HLP IIa) requires intervention if HDL ____
30 mg/dL, 160
88
Management of HLP IIa when TC is 200-240 WITHOUT CAD or 2 or more risk factors?
Prudent diet and re-check in one year
89
Management of HLP IIa when TC 200-240 WITH CAD or 2 or more risk factors?
Lipoprotein analysis with further action based on results
90
A cluster of metabolic abnormalities that confer an increased risk factor for type 2 DM, cardiovascular disease, stroke, fatty liver and certain cancers.
Metabolic syndrome (syndrome X, insulin resistance syndrome)
91
Predominant age for metabolic syndrome?
>60 (about 50% of cases)
92
What ethnicity is at the highest risk for metabolic syndrome?
Mexican Americans
93
Metabolic syndrome affects __% of US adults age >20 years old. This number is rising.
34%
94
To diagnose _____, you must have THREE of the following:
1. Abdominal obesity (waist circumference >40 inches in men, >35 in women)
2. TGs >/=150 mg/dL
3. Low HDL cholesterol (<40 men, <50 women)
4. BP >/= 130/85 mm Hg
5. Fasting glucose >/= 100 mg/dL
Metabolic syndrome
95
The fecal fat test measures the fat test in the stool. The total output of fecal fat per 24 hours in a ___ day stool collection provides the most reliable measurement.
3
96
The fecal fat test is done in the work-up of patients for possible _____ (oily, smelly stools)
Steatorrhea
97
Increased lipids (fats) in the urine
Chyluria
98
This occurs in acute starvation or in impaired carbohydrate metabolism. It is the body’s attempt to obtain necessary energy from stored fat in the absence of an adequate supply of carbohydrate metabolites.
Ketosis
99
The cause of ____ is an excessive degradation of fatty acids by beta oxidation in liver cells, resulting from an excessive mobilization of fatty acids from adipose cells. The body either does not have enough carbohydrates or has carbohydrate metabolism impairment (i.e. DM for example)
Ketosis
100
In children, one of the most common causes of steatorrhea is ____
Cystic fibrosis (mucous plugs obstruct the pancreatic ducts which don’t allow pancreatic enzymes to do their job and help absorb fat in the intestines)
