The document discusses cholesterol, its functions, and metabolism, highlighting its origins from both diet and liver synthesis. It details the importance of cholesterol testing, how the tests are conducted, and the interpretation of results, including recommended age for screening. Additionally, it outlines dietary recommendations, potential medications for managing cholesterol levels, and clinical implications of abnormal cholesterol levels.

1. TOTAL
CHOLESTEROL
Dhurgadharshini,
Pharm D – 1st Yr.

2. INTRODUCTION
Cholesterol is a type of fat, found in our blood.
It is found in our body and also come from the food we
eat(animal products).
It is made by liver and is also used by the liver to make
bile, which helps in the digestion of foods.
Cholesterol is also needed to make certain hormones and
to produce vitamin D.

3. STRUCTURE OF CHOLESTEROL

4. FUNCTIONS OF CHOLESTEROL
Its main function is to maintain the integrity and fluidity of cell
membranes.
To serve as a precursor for the synthesis of substances that are vital
for the organism including steroid hormones, bile acids, and vitamin
D.

5. METABOLISM OF CHOLESTEROL
Biosynthesis of cholesterol generally takes place in the endoplasmic
reticulum of hepatic cells and begins with acetyl- CoA, which is mainly
derived from an oxidation reaction in the mitochondria.
Triglycerides and cholesterol combine to form chylomicrons. Chylomicrons
enter the circulation and travel to peripheral sites. In peripheral tissues, free
fatty acids are released from the chylomicrons to be used as energy,
converted to triglyceride or stored in adipose.

6. WHY IT’S DONE
High cholesterol usually causes no signs or symptoms. A complete cholesterol
test is done to determine whether your cholesterol is high and to estimate your
risk of heart attacks and other forms of heart disease and diseases of the blood
vessels.
Cholesterol testing evaluates the risk for artherosclerosis, myocardial occlusion,
and coronary artherial occlusion.
It is a part of lipid profiles.
Elevated levels are major component in the hereditary hyperlipoprotenemias.

7. Cholesterol determinations are also frequently a part of thyroid function, liver
function, renal function, and diabetes mellitus studies.
It is also used to monitor effectiveness of diet, medications, lifestyle changes and
stress management.
A complete cholesterol test includes the calculation of four types of fats in your
blood:
 Total Cholesterol - This is a sum of your blood's cholesterol content.
 HDL - As we know earlier.
 LDL – As we know earlier.
 Tryglycerides - As we know earlier.

8. WHO SHOULD GET CHOLESTEROL TEST?
According to the National Heart, Lung and Blood Institute (NHLBI), a person's first
cholesterol screening should occur between the ages of 9 and 11 and then be
repeated every five years after that.
The NHLBI recommends that cholesterol screenings occur every 1 to 2 years from
men ages 45 to 65 and women ages 55 to 65. People over 65 should receive
cholesterol test annually.
More-frequent testing might be needed if your initial test results were abnormal
or if you already have coronary artery disease.

9. VALUES FOR CHOLESTEROL
Normal : less than 200 mg/dL.
Boderline : 200 to 239 mg/dL.
High : at or above 240 mg/dL.

10. PRE-TEST INSTRUCTIONS
You're generally required to fast, consuming no food or liquids
other than water, for nine to 12 hours before the test. Some
cholesterol tests don't require fasting.
A normal diet should be consumed for 7 days.
The patient should abstain from alcohol for 48 hours before testing.
Drugs like contraceptive pills should be avoided prior to test as
they alter the cholesterol levels.

11. DURING THE PROCEDURE
A cholesterol test is a blood test, usually done in the morning if you fast
overnight. Blood is drawn from a vein, usually from your arm.
Before the needle is inserted, the puncture site is cleaned with antiseptic and an
elastic band is wrapped around your upper arm. This causes the veins in your arm
to fill with blood.
After the needle is inserted, a small amount of blood is collected into a vial or
syringe. The band is then removed to restore circulation, and blood continues to
flow into the vial. Once enough blood is collected, the needle is removed and the
puncture site is covered with a bandage.

12. HOW DO YOU CALCULATE TC?
HDL + LDL + 20% triglycerides = total
cholesterol.
LDL = 100
HDL = 70
Triglycerides = 150
100+70+(150/5)
100+70+30 = 200mg/dL

13. AFTER THE PROCEDURE
Cholesterol levels >200mg/dL should be retested and the results averaged. If the
two results differ by >10%, a third test should be done.
Once hypercholesterolemia has been established, the diet should be lower in
animal fats and should replace saturated fats with polyunsaturated fats.
Fruits, vegetables and whole-grain products should be increased.
Atleast 6months of dietary therapy should be tried before intiating cholesterol-
reducing drug therapy.
Drug therapy involves statins(lovastatin, simvastatin, fluvastatin), clofibrate,etc.

14. Lovastatin – Adults(20mg/day).
Childrens(10mg/day).
Simvastatin – Usual dose range(5-40mg/day).
Initial(10-20mg/day).
Patients at high CHD risk(start 40mg/day).
Fluvastatin - Adults—80 milligrams (mg) once a day.
Children 10 to 16 years of age—80 mg once a day.
Clofibrate - Adults—1.5 to 2 grams a day. This is divided into two to four
doses.
Children—Dose must be determined by your doctor.

15.  Once low level of cholesterol has been established, the following alterations has to be
taken,
 Eat heart-healthy foods(Reduce saturated fats, Eliminate trans fats, Eat foods rich in
fatty acids, Increase soluble fiber, Add whey protein).
 Exercise on most days of the week and increase your physical activity
 Quit smoking
 Drink alcohol only in moderation.
 Drugs to increase the cholesterol levels are :
• Beta Blockers.
• Prednisone.
• Amiodarone.
• Cyclosporine.
• Anabolic Steroids.
• Protease Inhibitors.
• Diuretics.

16. CLINICAL IMPLICATIONS
Elevated cholesterol levels occur with the following conditions:
 Hyperlipoprotenemia, cholestasis, hepatocellular disease, nephrotic syndrome, chronic renal
failure, hyperthyroidism, poorly controlled diabetes mellitus, alcoholism, glycogen storage
disease(von gierke’s disease), werner’s syndrome, diet high in cholesterol and fats, obesity.
Decreased cholesterol levels occur in the following conditions:
 Severe hepatocellular disease, malabsorption syndrome, malnutrition, hyperthyroidism,
chronic anemias, conditions of acute illness, severe burns, chronic obstructive lung disease
and mental retardation.