About 90 percent of the cholesterol-lowering drugs taken by Americans are statins. The reason: Statins are the most effective medications for lowering total and LDL cholesterol levels and for reducing the risk of heart attacks and strokes (as well as the need for bypass surgery and angioplasty in individuals with coronary heart disease). What’s more, these drugs generally have few side effects.
Statins work by interfering with the activity of an enzyme called HMG-CoA reductase that is crucial for the production of cholesterol. Inhibiting this enzyme results in lowering the amount of cholesterol manufactured by the body.
The statin drugs are
- atorvastatin (Lipitor)
- fluvastatin (Lescol, Lescol XL)
- lovastatin (Altocor, Altoprev, Mevacor)
- pitavastatin (Livalo)
- pravastatin (Pravachol)
- rosuvastatin (Crestor)
- simvastatin (Zocor)
Lovastatin, pravastatin, and simvastatin are available in generic form. Some statins are available in combination with other lipid-lowering drugs; for example, the combination pill Advicor contains lovastatin and extended-release niacin, Simcor contains simvastatin and extended-release niacin, and Vytorin contains simvastatin and the cholesterol absorption inhibitor ezetimibe (Zetia). In addition, Lipitor is sold in combination with the blood pressure drug amlodipine (Norvasc) in a pill called Caduet.
On average, statins produce a 25 to 55 percent reduction in LDL cholesterol levels, a 5 to 15 percent increase in HDL cholesterol, and a 10 to 25 percent decline in triglycerides. But not all statins are equally effective in lowering LDL cholesterol and triglyceride levels. Crestor is the most potent, followed by Lipitor, simvastatin, Livalo, pravastatin, lovastatin, and Lescol. The ability to lower LDL cholesterol levels is usually the most important factor to consider when choosing a statin, but other considerations include your heart attack risk, possible side effects, interactions with other medications you are taking, cost, and the time of day doses are taken.
In addition to their positive effects on blood cholesterol and triglyceride levels, statins also appear to improve the function of the cells in the endothelium, which lines the arteries. Specifically, statins help arteries regain at least some of their normal ability to dilate and allow increased blood flow during exercise. Statins also reduce the risk of plaque rupture, which can trigger a blood clot that can lead to a heart attack. This risk reduction is achieved by decreasing the cholesterol content and the amount of inflammation in the artery walls.
Recently, researchers discovered that statins can lower blood CRP levels. CRP is a measure of inflammation in the body. Individuals with high levels of inflammation and CRP are at increased risk for a heart attack. In addition, some people with elevated CRP levels but normal LDL cholesterol may benefit from a statin, particularly if they are at intermediate risk for a heart attack.
Statin Side Effects
Statins produce side effects in 1 to 2 percent of people. The most common side effect is myopathy (muscle aches). Other possible effects include bloating or upset stomach and increases in liver enzymes. In rare cases, most often when a statin is used along with certain other drugs, such as gemfibrozil (Lopid) and some antifungal medications, the kidneys can be damaged by the release of a protein called myoglobin from severely inflamed muscles (a condition known as rhabdomyolysis). If you experience unusual or unexplained muscle aches while taking a statin, call your doctor as soon as possible.