How Statins Stave Off Bad LDL

Health Writer

Statins are the traditional drug of choice to lower low-density lipoprotein, or LDL, also known as “bad” cholesterol. For a more detailed explanation of cholesterol, see this article on the topic. LDL is bad because at high levels it gets into the bloodstream and sticks to arteries to form plaques, or deposits. These deposits can create blockages that interfere with the flow of blood to vital organs. Part of a plaque may break off and flow into the bloodstream before hitting a vital organ. The result may be a heart attack or stroke, either of which can be fatal.

Suspicion of a link between LDL and cardiovascular disease led to intense study of cholesterol production by scientists whose research identified four stages. A chemical reaction in the first stage provided a likely target. If they could interfere with HMG-CoA, they might be able to reduce cholesterol production. The first success story was compactin, which interfered with cholesterol production, but was discontinued. Why? Because dogs given doses much higher than the amount given to people developed lymphoma and other cancers.

The next test drug was lovastatin, but fear of the drug’s similarity to compactin delayed testing for a year, then resumed because prior results were too impressive to dismiss. LDL levels had fallen dramatically. In 1987, after clinical trials confirmed lovastatin’s effectiveness and safety, the Food and Drug Administration put the first statin on the market. Today there are many variants clearly related by their generic names, and among them are atorvastatin, fluvastatin, pravastatin, rosuvastatin, simvastatin, and pitavastatin.

All statins interfere with the HMG-CoA chemical reaction that is necessary to make cholesterol.Statins lower LDL by 25 percent to 35 percent and reduce the incidence of heart attacks by about 25 percent to 30 percent. Moreover, side effects for many people are minimal. In 2013, the American College of Cardiology (ACC) and American Heart Association (AHA) published a Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults.

The ACC/AHA guideline specifies treatment recommendations for four groups of people likely to benefit from cholesterol-lowering statin therapy and reduce risk of heart attack and stroke. The groups include (1) patients who have cardiovascular disease; (2) patients with bad LDL of 190 mg/dL or higher; (3) patients with Type 2 diabetes who are between 40 and 75 years of age; and (4) patients with an estimated 10-year risk of cardiovascular disease of 7.5 percent or higher who are between 40 and 75 years of age. Determining your risk level is best done during a consultation with your doctor.

Statins can have side effects such as muscle pain, increased blood sugar or onset of Type 2 diabetes, memory loss and confusion, and liver damage, with the last being very rare. Not everyone experiences side effects. Those at higher risk for side effects are women and people with a small body frame, aged 65 or older, with kidney or liver disease, who drink alcohol excessively, and who take several cholesterol-lowering drugs.

If statin side effects occur, they can be managed. A doctor may suggest another type of statin, a different dose, moderation of physical activity, or other types of cholesterol-lowering medications. Someone with side effects should not stop the drug without first talking to a doctor.