Biochemistry and Clinical Pathology (S.Y. D.Pharm) 12.

22 Organ Function Tests

12.7 LIPID PROFILE TESTS AND THEIR CLINICAL SIGNIFICANCES

The lipid profile means total lipids present in blood. The lipid profile generally affects the
health of the coronary system. Therefore, any abnormal lipid protile causes diseases of the
circulatorysystem especially atherosclerosis, heart diseases, pancreatitis etc. The lipid profile
is the group of tests that is carried out to determine the risk of coronary heart disease. These
tests are good indicators to know before about the heart attack or stroke caused by
atherosclerosis.
The Lipid Profile includes:
Total cholesterol (TC), High density lipoprotein cholesterol (HDL-C), Low density
lipoprotein cholesterol (LDL-C), Triglycerides (TGs) and very low density lipoprotein
cholesterol (VLDL-C).
Cholesterol is awaxy substance. It is essential for bodily functions at normal levels for
contributing to the structure of cell walls, allowing the body to produce vitamin D, making up
digestive bile acids in the intestine and enabling the body to make certain hormones. But
sometimes excess of cholesterol is also deposited in the body and create many health
problems. The main causes of high levels of cholesterol are:
Genetics: If high cholesterol persists in family, then one might be at a greater risk than
others.
Current Lifestyle: Lifestyles that entail junk food, alcohol, heavily processed meats and
dairy on a daily basis, smoking and not being physically active could increase cholesterol
levels in body.
Diet: It is important to eat healthy food. Trans fat (packaged and fried foods) and
saturated fat (cheese, butter, egg yolks, whole milk and meats) can cause high
cholesterol.
Weight: Overweight human may generally get the chances of having problems with high
cholesterol.
Medical History: If anyone in his family had a history of heart disease, high cholesterol
levels, then next generations are more prone to have heart disease.
Total Cholesterol (TC): TC is the overall amount of cholesterol found in the blood.
It consists of low-density lipoproteins (LDLs), high-density lipoproteins (HDLS) and
triglycerides.
High-density Lipoproteins (HDL): HDL-C is known the good cholesterol because it acts
as a shield and removes harmful bad cholesterol. It scavenges cholesterol from the
bloodstream, from LDL, and from artery walls and carry it back to the liver for disposal. As a
high level of HDL in body, protects against heart attack and stroke.
Low-density Lipoproteins (LDL): LDL-C carries cholesterol from the liver to the rest of
the body. Cells latch onto these particles and extract fat and cholesterol from them. In the
blood these LDL particles can form deposits in the walls of the coronary arteries and other
arteries throughout the body, when there is to0 much LDL cholesterol. These deposits are
known as plaque which can narrow arteries and limit blood flow. When plaque breaks apart,
it can cause a heart attack or stroke. Hence, it is often known as 'bad' cholesterol or harmtul
cholesterol due to increase their risk of many fatal diseases such as atherosclerosis (blocking
of arteries), which can lead to cardiovascular diseases.
Biochemistry and Clinical Pathology (S.Y. D.Pharm) 12.23 Organ Function Tests

Triglycerides (TGs): TGs act as storing of energy in adipocytes and muscle cels. They are
lipids or tats. Most ofthe fats we eat, including butter, margarines, and oils, are in triglyceride
form. Excess calories, alcohol or sugar in the body turn into triglycerides and are storedin tat
cells throughout the body.
Very Low Density Lipoprotein Cholesterol (VLDL-C): VLDL-C secrets from liver and
released intothe bloodstream to supply body tissues with a type of fat (triglycerides). Ihis 15
also known as bad cholesterol because it helps in formation of plaque in arteries that results
atherosclerosis. This limits the flow of oxygen-rich bloodto body.
All lipid profile tests are performed through blood test. A small sample of blood is taken
from human arm and then analyzed in a laboratory. The total cholesterol, HDL, LDL, and
triglycerides are measured in the blood stream. The ranges of lipid profile in body are shown
in Table 12.6 for adults and Table 12.7 for children.
Table 12.6: Ranges of Lipid Profile in Human Body (For Adults)
Lipid profile Normal Borderline high High Very high
(mg/dL) (mg/dL) (mg/dL) (mg/dL)
At 240 More than 240
Total cholesterol Less than 200 200 - 239
Less than 100 130 to 159 160 to 189 More than 189
LDL-C
150 to 199 200 to 499 Above 500
Triglycerides Less than 150
HDL-C Less than 60 35-45 Less than 35

Cholesterol-HDL 4.0 5.0 6.0

ratio
Table 12.7: Ranges of Lipid Profile in Human Body (For Children)
TC HDL-C LDL-C TGs
Effect
Good 170or less More than Less than Less than 75 (for age group 0-9 yrs)
45 110 Less than 90 (for age group
10-19 yrs)
Borderline 170-199 40-45 110-129 75-99 (for age group 0-9 yrs)
90-129 (for age group 10-19 yrs)
200or NA 130 or More than 100 (for age group
High 0-9 vrs)
higher higher
More than 130 (for age group
10-19 yrs)
NA Less than 40 NA NA
Low
Lipid Profiles and their Clinical Significance:
an
Primary prevention recommendations for adults age between 40 to 75 years old with
LDL level of 70to 189 mg/dL. High levels of low-density lipoprotein-cholesterol (LDL-C) and
low levels of high-density lipoprotein cholesterol (HDL-C) are risk factors for coronary heart
disease. Large clinical trials have shown that lowering LDL-C levels significantly reduce
cardiovascular events and mortality rate. Increased plasma lipoproteins is known as
hyperlipoproteinemia and decreased plasma lipoproteins is known as hypolipoproteinemia.