Cholesterol is necessary for various functions of the body such as maintaining healthy cell walls, making hormones, vitamin D and bile acids. However, high levels of cholesterol in the blood can lead to atherosclerosis, where cholesterol builds up in the artery walls causing hardening, narrowing and blockage. This prevents oxygenated blood from reaching the heart and can result in heart disease. High cholesterol levels can exist in the absence of signs and symptoms, so a simple blood test for screening cholesterol called a complete cholesterol test, lipid panel or lipid profile is performed to identify the risk of heart disease.
In a complete cholesterol test, the blood is evaluated for four types of cholesterol:
- Low-density lipoprotein or LDL cholesterol (also called bad cholesterol) causes build-up of fats in the arteries and reduces blood flow to the heart.
- High-density lipoprotein or HDL cholesterol (also called good cholesterol) helps in clearing out the LDL.
- Triglycerides are fats in the blood which get stored in the fat cells of your body.
- Total cholesterol is the blood's total cholesterol content.
Indications for Cholesterol Screening
Cholesterol screening is indicated once every five years in adults aged 18 or older. Other reasons for cholesterol testing include:
- Family history of heart disease or high cholesterol
- Being overweight
- Being physically inactive
- Having diabetes
- Over age 45 in men or 55 in women.
- Smoking habit
- Hypertension (high blood pressure)
Cholesterol screening is also indicated in children between 2 to 10 years that have a family history of high cholesterol or premature coronary artery disease.
Before the blood test, you will have to fast for 9 to 12 hours and consume only water. Avoid coffee, tea and other beverages. You may need to stop certain medications a few days before the test if they may affect the test results.
Procedure of Cholesterol Screening
The cholesterol screening test is performed in the morning. An elastic band is wrapped around your upper arm which causes the veins to fill with blood. The skin is cleaned with antiseptic solution and a needle is inserted into a vein. Blood is drawn and collected in a vial. The puncture site is then covered with a bandage.
Results of Cholesterol Screening
Total cholesterol greater than 240 milligrams per decilitre (mg/dL) is considered high. Borderline cholesterol level lies between 201 to 240 mg/dL. Lower than 200 mg/dL is considered normal.
Keeping LDL levels less than 100 mg/dL is considered good for health. LDL levels within the range of 160 and 189 mg/dL is considered high and above 190 mg/dL is very high.
HDL cholesterol levels of 60 mg/dL or higher is considered good for the heart; a range of 40 to 59 mg/dL is acceptable, whereas less than 40 mg/dL is considered low.
Treatment for Abnormal Cholesterol Levels
To lower your LDL levels your doctor will recommend appropriate lifestyle changes and drug therapy.
Therapeutic lifestyle changes include weight management, physical activity and a cholesterol-lowering diet.
If your cholesterol levels are inadequately controlled by lifestyle changes your doctor may prescribe medications.
Lifestyle changes and medications can also help control high triglyceride levels.