History
Television commercials for statin drugs bombard the American public. High cholesterol levels have been linked to increased risk of stroke and heart disease. Before the development of statin drugs, cholesterol medications would bind to cholesterol in the gastrointestinal tract so it could be expelled with the stool. These caused unpleasant side effects such as gas and bloating.
Since the introduction of lovastatin in 1987, statins have played a major role in the treatment of high cholesterol. Statins are more effective and better tolerated than previous cholesterol drugs.
Cholesterol in the Body
Cholesterol is a substance that the body needs to make hormones, cell membranes and the bile used in digestion. Because cholesterol doesn't dissolve in water, it's carried through the blood in particles called lipoproteins. Lipoproteins consist of cholesterol molecules and proteins, and are classified according to their size.
Low-density lipoproteins (LDL) are smaller particles that carry cholesterol to the tissues of the body. High-density lipoproteins (HDL) transport cholesterol molecules back to the liver. HDL also picks up extra LDL cholesterol in the bloodstream. Because LDL cholesterol particles can stick to artery walls and cause plagues, HDL's ability to pick them up and carry them back to the liver earns it the nickname of "good" cholesterol.
The cholesterol molecules contained in LDL particles and HDL particles are the same. The density of the particles that carry cholesterol molecules through the body determines how they affect your health.
Sources of Cholesterol
Your body gets some cholesterol from the foods you eat, but it can also manufacture cholesterol in the liver. The manufacture of cholesterol is a multiple-step process that relies on enzymes. Statins inhibit the action of the enzyme known as HMG-CoA reductase, an enzyme essential to cholesterol formation. Not only does this decrease the amount of LDL cholesterol the liver makes, it increases the number of receptors in the liver that pull LDL out of the bloodstream. As a result, LDL cholesterol is lowered. Statins can also lower triglycerides and slightly increase HDL, or "good" cholesterol.
Side Effects
Most people who take statins tolerate them very well. Two of the most noteworthy side effects are the elevation of liver enzymes and muscle pain. Although increased levels of liver enzymes in the blood is often a sign of liver damage, enzyme levels usually return to normal after the drug is stopped. People taking statins who experience muscle pains or aches should talk to their doctors.
References
- Basic and Clinical Pharmacology; Bertram Katzung; 2007
- Conn's Current Therapy; Robert E. Rakel and Edward T. Bope; 2009
- Cardiovascular Therapeutics; Elliott Antman; 2006
