Lifestyle measures are typically considered the first step and the cornerstone for preventing heart attacks—and they may be all that are needed. But if they fail to adequately control cholesterol levels and high blood pressure (usually within three to nine months), medication is often recommended in addition to lifestyle changes.
Over the past decade, several landmark studies have confirmed that lowering elevated levels of LDL (“bad”) cholesterol reduces cardiovascular risk. Based on such findings, the National Cholesterol Education Program has recommended lower LDL cholesterol targets ranging from less than 160 mg/dL to below 70 mg/dL, depending on cardiovascular risk factors.
In the past 16 years, a total of seven so-called statin drugs have come on the market. All statins lower cholesterol by at least 20% through the same basic action: Statin drugs inhibit HMG-CoA reductase, a key enzyme that controls how much cholesterol is produced in the liver. The result is lower blood levels of LDL cholesterol. Statin drugs also increase high density lipoprotein (HDL, or “good”) cholesterol; reduce inflammation in arterial walls; relax blood vessels; improve blood flow to the heart; inhibit clotting; and stabilize the fatty plaques that form in the walls of arteries. More research is needed to determine the clinical significance of these effects.
Comparing Potency of Various Statin Drugs
Direct comparisons of the potency of the various statin drugs are limited. One noteworthy study is The Statin Therapies for Elevated Lipid Levels Compared Across Doses to Crestor (STELLAR) trial, reported in 2003 in the American Journal of Cardiology.
A randomized, controlled trial that involved more than 2,400 people, STELLAR compared the three most widely prescribed statin drugs —Lipitor (atorvastatin), Zocor (simvastatin), and Pravachol (pravastatin)—with the newest, Crestor (rosuvastatin), across a range of doses. After 6 weeks of treatment, Crestor lowered LDL cholesterol by 46% to 55%, compared with 37% to 51% for Lipitor, 28% to 46% for Zocor, and 20% to 30% for Pravachol. Crestor and Lipitor also lowered triglycerides by 20% to 28%, significantly more than Pravachol (8% to 13%) or Zocor (12% to 18%).
The ability of statin drugs to lower LDL cholesterol is the most important factor to consider when choosing a statin—but other factors may also influence statin choice. Statin drugs vary in price, the time of day they should be taken, interactions with other drugs, and side effects.
If your initial cholesterol level is only mildly elevated, your doctor may opt for any of the statin drugs. On the other hand, if you are at elevated risk for heart disease, your initial cholesterol level is very high and your triglyceride levels are also high, or you’ve failed to respond adequately to one of the other statin drugs, a more potent formulation—like Lipitor or Crestor—may be more appropriate.
Combination Therapy to Lower Cholesterol
Another option is to combine a statin with a different type of cholesterol-lowering drug such as Zetia (ezetimibe), which works by a different mechanisim: It inhibits the absorption of cholesterol by the intestine. The combination of a statin and Zetia can lower LDL cholesterol more than a statin alone. Patients can take separate pills for each drug or choose a new drug, Vytorin, which combines 10 mg of Zetia with Zocor at different dosages.
Similarly, other drugs can be combined with a statin when high LDL cholesterol levels are accompanied by low HDL cholesterol levels or high triglycerides. Niacin, a B vitamin available as an extended-release prescription drug called Niaspan, is the most effective agent for raising HDL levels. Fibrates (fenofibrate and gemfibrozil) are the treatment of choice for people with markedly high triglyceride levels.
No matter which drug regimen is chosen, the standard approach is to start at a lower dosage and increase the dosage if a greater drop in LDL cholesterol levels is needed.
