Basic Lab ¬ PREVU Skin Sterol testPREVU Skin Sterol Test non-invasively and painlessly measures skin tissue cholesterol, or skin sterol. As a new risk factor for heart disease, skin sterol provides valuable additional information to traditional CAD risk assessment. Skin contains over 11% of the body’s cholesterol and ages in parallel with vascular connective tissue. As blood vessel walls accumulate cholesterol, so do the skin tissues. A high skin sterol level is a reliable predictor of higher cholesterol accumulation in the arteries and, accordingly, risk of heart disease.
What is coronary artery disease (CAD)?
Coronary artery disease, or heart disease, is a leading cause of death worldwide. Heart disease occurs when fat and cholesterol gradually accumulate in the coronary arteries, forming a plaque that narrows the artery and reduces blood flow to the heart. Undetected or untreated, this build-up can block the artery and cause a heart attack. A heart attack, also known as a myocardial infarction (MI), causes a part of the heart muscle to die, which weakens the heart’s ability to pump blood. Worldwide, about 7.3 million people die from heart attacks every year.
What are the risk factors for CAD?
A major risk factor for CAD is high blood cholesterol. It is estimated that clinical laboratories in the U.S. now perform approximately 250 million cholesterol tests per year and another 290 million clinical laboratory tests are performed in the rest of the world.
However, blood cholesterol tests may be highly variable in results over a series of days, relatively expensive to perform and require a fasting blood sample from the patient.
In fact, several studies suggest that about half of all heart attack patients actually have blood cholesterol levels within what is considered a normal, healthy range. So while blood cholesterol remains an important risk factor for heart disease, it is widely accepted that several risk factors for CAD must be considered to provide an accurate picture of absolute risk of disease.
Absolute cardiovascular disease risk is determined by a combination of all cardiovascular risk factors present. Other traditional and emerging risk factors include:
Many of these factors are costly to measure or assess, are resource intensive and inappropriate for a primary care setting, or require invasive procedures.
- Gender;
- Increasing age and heredity;
- Tobacco smoking;
- High blood pressure;
- Physical inactivity, diet and obesity;
- Diabetes mellitus;
- C-reactive protein (CRP);
- Homocysteine;
- Carotid intima-media (CIMT) thickness; and
- Coronary calcium, among others.
About PREVU* Skin Sterol Test
PREVU* Point of Care (POC) Skin Sterol Test is a non-invasive, painless and cost-effective tool to measure skin sterol that does not require any patient preparation or dietary changes.
This simple test is conducted by placing a drop of digitonin, which binds selectively to the sterol in the skin, on the palm of the hand. This liquid also contains an enzyme (horseradish peroxidase) linked to the digitonin by a copolymer. After a one-minute incubation period, the area is blotted dry to remove any unbound digitonin solution. A second drop of liquid is then added, containing a substrate for the horseradish peroxidase enzyme. When combined, a blue color change occurs in direct proportion to the amount of digitonin that is bound to skin sterol. After two minutes, a hand-held spectrophotometer (color reader) is placed over the drop to measure the precise blue color, which indicates the skin sterol value.