(CBS) High cholesterol is a health problem for an estimated 71 million Americans, and how some of them are treated may soon be changing.
The American College of Cardiology and the American Heart Association unveiled new treatment guidelines for high cholesterol on Tuesday. The updated regulations are aimed at people who are at high risk for heart disease caused by atherosclerosis.
Atherosclerosis is a disease in which plaque made up of fat, cholesterol, calcium and other substances found in blood build up inside the arteries, narrowing them and preventing oxygen-rich blood flow from reaching the body. It can cause heart attack, stroke or sudden death.
The new guidelines recommend cholesterol-lowering drugs called statins to four groups of patients who have the greatest odds of preventing heart attack and stroke on the drugs:
People who have heart disease
People with an LDL, or "bad" cholesterol level of 190 mg/dL or higher
People with Type 2 diabetes who are between 40 and 75 years old
Patients with an estimated 10-year risk of heart disease of 7.5 percent or higher who are between 40 and 75 years of age
This differs from previous guidelines that emphasized a series of goal targets for LDL cholesterol that would determine whether a patient is at high risk that also factored in diabetes status and other risk factors. Instead, these four above groups will have more aggressive statin therapy.
"The likely impact of the recommendations is that more people who would benefit from statins are going to be on them, while fewer people who wouldn't benefit from statins are going to be on them," Dr. Neil J. Stone, chair of the expert panel that wrote the new guidelines and a professor of medicine at Northwestern University Feinberg School of Medicine in Chicago, said in a statement.
The new guidelines also introduce a shift from previous treatments that rely on giving low doses of statins in combination with other cholesterol drugs. Previously doctors were told to take a "lowest dose is best" approach for prescribing the drugs.
Instead, the cardiology groups said it's preferable to focus on a healthy lifestyle in addition to prescribing higher-dose statins, eliminating the needs for those other cholesterol drugs.
"Considering all the possible treatments, we recommend a heart-healthy lifestyle and statin therapy for the best chance of reducing your risk of stroke or heart attack in the next 10 years," said Stone.
Dr. Donald Smith, director of the Lipids and Metabolism Program at The Mount Sinai Hospital in New York City, told CBSNews.com that the guidelines will change practice by getting those at highest risk on more aggressive, higher dose statins with less use of add-on drugs, like niacin and fenofibrate.
He explained the guidelines changed from goal-oriented treatment targets because studies typically compared high-dose statins versus low-dose statins, and found higher doses were shown to better than lower ones. Even if someone, say a patient with diabetes, met a goal with low-dose treatment and got their LDL down from 100 mg/dL to 70 mg/dL, the research suggests he or she could have done better with higher doses of statins.
"You need to be on a high-dose statin to prevent the disease," said Smith.
He doubts the guidelines will cause many patients to be taken off of statins, since most will fit into one of the new categories. If anything, he predicts more people may use them once they have their 10-year disease risk calculated.
Smith said patients should stick tight to whatever cholesterol-altering medications they are on, until they can discuss the new guidelines with their doctor, who are also trying to figure out how the new shift will affect treatment.
"Stay on what you're on, wait until the smoke clears (in three to six months) and talk to your physician," he recommended.
Statins are among the most commonly-prescribed drugs in America, taken by an estimated 32 million people, according to 2011 estimates from Harvard Medical School. The Mayo Clinic notes they are well tolerated by most people, but can lead to side effects including muscle and joint aches (most common), nausea, diarrhea and constipation. Other more serious potential side effects include liver damage, muscle pains and other problems, neurological side effects like memory loss or increased blood sugar that may lead to Type 2 diabetes.
Recent research has also linked the drugs to cataract risk. Last year, a large study in The Lancet of more than 17,600 people found the reductions in heart problems outweighed the added risk of diabetes for at-risk patients.
In Feb. 2012, the Food and Drug Administration added warning labels to statin medications that warn of memory loss and confusion reported among some patients. The labels also mention elevated levels of blood sugar associated with diabetes has been reported in some patients.
Examples of statin drugs include Lipitor (atorvastatin), Crestor and Zocor (simvastatin).
The new guidelines were published in the ACC's and AHA"s flagship medical journals, but could also be accessed on the medical societies' websites.
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