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Monday, February 1, 2010

The Statin Epidemic

Millions of people in the United States take statin medications to lower cholesterol and prevent heart disease. Some think that statins are the new wonder drug while others wonder whether the benefits outweigh the risks. With research studies uncovering questionable gain and serious side effects, critical concerns are justified. A thorough understanding of the way that statins work helps explain why they may not be the key to healthier hearts and longer lives.

Lower Levels of Cholesterol

Statins block the activity of enzyme HMG-CoA reductase, an essential step in the synthesis of cholesterol. Inhibition of this enzyme prevents the body from producing cholesterol, therefore lowering levels in the blood.

Cholesterol has several important functions in the body and we can’t live without it. It acts as an antioxidant, a repair molecule and an essential component of all cell membranes. Cholesterol is used to make sex hormones, including estrogen, progesterone and testosterone, and adrenal hormones, which help our bodies deal with stress and regulate blood volume. Cholesterol is used to make bile, which aids the digestion and assimilation of dietary fats, and vitamin D, which increases absorption of calcium, builds strong bones, strengthens the immune system and provides protection against hypertension, autoimmune disease and cancer.

Cholesterol also accounts for approximately half the dry weight of the brain, where it plays a vital role in insulating neurons and allowing cells to communicate. When the body doesn’t make enough cholesterol, neurological problems can arise. Not surprisingly, side effects of statins include cognitive impairment, memory loss, mental confusion, difficulty concentrating, insomnia, personality changes, depression, anxiety, irritability and violent behavior.

Deficiency of Coenzyme Q10

Statins also inhibit the synthesis of coenzyme Q10, an antioxidant and essential cofactor in the production of energy inside cells. Because heart cells have such large energy requirements, they contain the highest concentrations of CoQ10. Deficiencies can weaken the heart and compromise cardiovascular function.

The deficiency of CoQ10 caused by statins can start soon after treatment begins. A study at Columbia University found that after only 14 days of treatment with atorvastatin (Lipitor), CoQ10 levels were reduced by 49 percent. Once CoQ10 is lacking, heart problems can quickly follow, even in people who have no history of cardiovascular disease. A study published in the American Journal of Cardiology followed adults who were healthy aside from mildly elevated levels of cholesterol. After only 6 months of taking a low dose of Lipitor, 71 percent of participants developed early heart muscle dysfunction.

Some side effects of statins are related to the loss of CoQ10 in muscles and a reduced capacity for energy production. These include fatigue, shortness of breath, problems with mobility and balance, and muscular pain, weakness and atrophy. Severe reactions can lead to rhabdomyolsyis, the destruction of skeletal muscle that is sometimes fatal. CoQ10 deficiency has also been linked to heart failure, hypertension and Parkinson's disease.

Other Adverse Effects

A study published in the Journal of the American Medical Association found that all statins (as well as fibrates, another class of lipid-lowering drugs) caused cancer in animals, in some cases at doses comparable to those prescribed in humans. A randomized, placebo-controlled trial published in the New England Journal of Medicine linked statin medications to an increased risk of breast cancer. Researchers followed 4159 men and women with normal cholesterol levels between the ages of 21 and 74 for an average of five years. Participants were divided into two groups: one was given pravastatin (Pravachol) and the other, a placebo. At the end of the study, 12 women in the pravastatin group had developed breast cancer while only one case occurred in the placebo group.

Other side effects include nausea, heartburn, abdominal cramps, diarrhea, constipation, headaches, asthma, skin rash, hair loss, impotence, inflammation of the pancreas and liver damage.

Questionable Benefits

The benefits of statins are questionable and major studies have failed to show protective effects. A trial published early this year in the American Journal of Cardiology found that statin medications taken to lower cholesterol actually increased the risk of death. Researchers followed adults diagnosed with heart failure for an average of 3.7 years, and in some cases up to 11.5 years. They found that participants taking statin drugs who had the lowest levels of low-density lipoprotein (LDL) had the highest rates of mortality. Incidentally, higher levels of cholesterol were associated with a lower risk of death.

The reduction of cholesterol is widely believed to be beneficial in preventing heart disease, but only half of all people who suffer heart attacks and strokes have high cholesterol. The Journal of the American Medical Association published a trial that compared older adults with high cholesterol (levels above 240 mg/dl) to those with normal levels (below 200 mg/dl). For four years, researchers at Yale University measured total cholesterol and high-density lipoprotein (HDL) in almost 1,000 participants and tracked the rates of death from heart disease, death from any cause, and hospitalizations for heart attack and unstable angina. They found no differences between the two groups. People with high cholesterol had as many heart attacks and died just as often as individuals with low cholesterol. A large review of 22 controlled trials published in the British Medical Journal also found no correlation between cholesterol levels and heart disease.

Alternative Interventions

Lowering cholesterol is not the best way to prevent heart disease. The most effective lifestyle interventions include regular exercise, weight control, stress management and a healthy diet low in refined carbohydrates like sugar and flour, and high in antioxidant-rich fruits and vegetables.

Supplemental nutrients can also improve outcomes. For example, fish oil can reduce inflammation, lower blood pressure, thin the blood to prevent blood clots, and decrease levels of triglycerides, slowing accumulation of atherosclerotic plaques that can block coronary arteries. Fish oil has also been shown to reduce the risk of heart attack, dangerous arrhythmias, stroke and death.

But before starting any new supplements or discontinuing any statin medications, schedule an appointment with your doctor. Ask about evaluating your risk of cardiovascular disease using indicators more reliable than cholesterol tests: homocysteine, lipoprotein A, LDL particle size, and C-reactive protein, a measure of inflammation.

References

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