HEALTH NEWS

By Brooke Bostic, MD, Greene Family Medicine
Published: December 3, 2008

In a previous article, I had the opportunity to explain some of the biology and practical implications of cholesterol metabolism and how various lifestyle choices and genetics can impact our cholesterol levels.  Getting our cholesterol level right continues to be a major topic for our culture and for the individuals I see in my office every day.  It is always a little confusing because what is considered an acceptable cholesterol level for a person who does not have risk factors - such as family history of heart disease, smoking, hypertension, diabetes, or other vascular disease - is not considered to be an acceptable level when risk factors are present.  For example, a 50-year-old person with no medical problems and an LDL (bad) cholesterol level of 140 is considered to have acceptable control.  When that person is diagnosed with hypertension, it is then recommended that his LDL level be 100 or less, and if that same person develops diabetes, heart disease, or a stroke, it is recommended that his LDL level be below 80.  HDL (good) cholesterol does provide protection, and total cholesterol consists of both HDL and LDL levels, as well as other components.  Treatment recommendations are not made based on the total cholesterol level but are based specifically on LDL (bad) cholesterol, HDL (good) cholesterol, and triglycerides (the fat level in the blood). 
Once it is determined that a certain level of LDL is unacceptably high based on a person’s risk factors, steps and therapies are recommended to reduce this level.  As we discussed previously, dietary changes, such as high fiber and reduced intake of cholesterol and carbohydrates, as well as aerobic exercise, can be extremely effective in lowering cholesterol levels for some people.  These are called lifestyle changes and are always the first recommendations for improving cholesterol.  A high-fiber diet could consist of whole grains, nuts, beans, and vegetables, as well as fiber supplements, such as Fiber One or All-Bran cereals.  Metamucil and other over-the-counter fiber supplement pills, powders, and drinks are also available.  Vigorous walking for a total of 30 minutes a day is also considered to be an effective additional benefit.  Both exercise and dietary changes might reduce LDL as well as increase HDL.  Both these changes are beneficial in reducing the risk of cardiovascular disease.  If these measures are not effective or if a person is unable to make these changes based on physical limitations, then medication is the next step. 
There are basically four main categories of cholesterol medication.  The largest and most commonly used are called statins.  These include generic and non-generic medicines.  The non-generics include Crestor and Lipitor.  The generics include simvastatin, pravastatin, lovastatin, and niacin (a B vitamin).  Niacin is a subcategory because it has different side effects and is also more effective than any of the others at increasing HDL, the good cholesterol.  Statins primarily lower LDL cholesterol with minimal benefit on HDL.  They are usually well tolerated but can cause leg or muscle discomfort and fatigue, and rarely, more significant muscle inflammation.  Many cardiologist recommend coenzyme Q10 as a vitamin supplement that can counteract side effects of statin medications to a noticeable degree.  Liver enzymes must be monitored while on statin medications, as there is a risk of liver inflammation from these medications as well, although it is uncommon for it to be severe.  Different individuals may have side effects from one of the medications in the statin category and not others.  The statin medications work in the liver to reduce cholesterol production and can drop LDL levels by 50% in some people.  Niacin is also an effective statin medication but does have a higher risk of side effects that can be unpleasant.  These are typically hot flashes and skin flushing, which occur more often as higher doses are taken but seem to fade in their frequency and intensity as the medication is taken over months and years.  Taking a baby aspirin approximately 30 minutes before taking the niacin dose significantly reduces the flushing side effect.  Niacin is often given to help raise a low HDL (good) cholesterol level, which if low in a person’s body increases the risk of heart disease in a similar degree as high LDL levels would. 
Zetia is another agent that is not a statin and is prescribed by itself or as a combination pill with simvastatin to lower LDL levels.  It works in a different way and typically has fewer side effects; in particular, it does not cause leg and muscle pain and fatigue as often as statins do.  Its action is to prevent the reabsorption of cholesterol that has been secreted into our intestinal tract in the form of bile or consumed in our diet.  This way, the cholesterol that we eat or secrete into our intestines is not reabsorbed into our bodies, and this effectively lowers our cholesterol level.  This is typically not considered to be as powerful a medication as the statin medications.  It is helpful in people who cannot tolerate the statin medications, or when used in addition to a statin if their levels are still considered too high with a statin alone. 
Another group of cholesterol medications are for lowering the triglyceride component, which is the fat level in the blood.  Lopid, Tricor, and fenofibrate are names in this group.  These do not generally cause muscle cramps or fatigue and have some overall cholesterol-lowering effect.  Exercise and reducing carbohydrates in the diet also lower the fat level in the blood. 
The last and newest category of cholesterol medications are from refined fish oil.  Fish oil has components that keep the plaques that form in our arteries softer and less likely to rupture and cause blockage.  These oils also act in other ways to help reduce cholesterol levels.  Lovaza is a prescription version of fish oil that is concentrated and has been shown to raise HDL levels and provide other benefits to reduce the risk of strokes and heart attacks.  Taking fish oil over the counter is a recommended supplement for anyone with any cardiovascular risk.  Flaxseed oil has similar omega-3 fatty acid chains but has not been shown to have the same benefits in clinical trials.  It is, however, an alternative for people who do not tolerate fish oil. 
There are a few dietary supplements that have been shown to have beneficial effects on cholesterol levels that are important to mention.  Avocado, garlic, guar gum, and oat bran have been shown to lower LDL.  Avocado has also been shown to raise HDL.  In regard to overall cholesterol reduction, avocado, blond psyllium, flaxseed, garlic, guar gum, niacin, oat bran, and red yeast have all been shown to provide some benefit.  Niacin has been shown also to help lower LDL and raise HDL, as mentioned previously. 
In summary, it is important to realize that there are a variety of ways to reduce cholesterol levels, from lifestyle choices to medications, and if one medication is not tolerated, others may work well without noticeable side effects.
This article is one in a series of monthly columns by Greene Family Medicine where doctors will answer your health-related questions. If you have any questions that you would like to ask a doctor for this column, please send them to: Greene Family Medicine, Attention: Paige Herndon, 140 Stoneridge Drive, Suite 100, Ruckersville, Virginia 22968