What you should know about the new lipid guidelines
David Schroeder, M.D.
Cardiologist, Providence Heart Clinic at The Oregon Clinic Gateway
The American College of Cardiology and the American Heart Association released new guidelines in November that are changing decades-old standards for treating cholesterol. These guidelines aren’t based on new evidence but instead on reassessment of existing data.
A major change within the guidelines is a greater emphasis on atherosclerotic cardiovascular disease risk rather than on specific cholesterol levels. Atherosclerotic cardiovascular disease, or ASCVD, is now defined more broadly and includes stroke and peripheral arterial disease.
Treating to a goal LDL no is longer required. Instead, repeat lipid testing is recommended only to confirm statin compliance. High-intensity statin therapy is recommended for most patients who require a statin. Non-statin medications, such as ezetimbe, niacin and fibrates, are discouraged except in patients who truly are statin intolerant. A more conservative approach is recommended for patients 75 or older who do not have a diagnosis of ASCVD.
Four groups of patients are recommended for intense statin treatment:
- Adults with clinical ASCVD, which encompasses coronary artery disease, peripheral artery disease, transient ischemic attack or stroke
- Adults age 40 to 75 with diabetes
- Adults of any age with LDL above 190
- Adults age 40 to 75 whose LDL is between 70-189, and who have a 7.5 percent or higher risk of ASCVD over a 10-year period
Controversy about this fourth group has been intense. Much of the debate centers on the new
risk calculator, which may overestimate the risk of ASCVD. It has been suggested that 1 billion people will now qualify for statins worldwide.
Mayo Clinic expanded on the calculator in a recent issue of
and now offers an interactive statin
Are there data to support statins in this fourth group?
Yes. A recent meta-analysis shows that use of statins for primary prevention reduces risk of ASCVD and mortality and that the drugs’ benefit extends even to people whose 10-year risk is less than 5 percent.2
In this group, each one-point reduction in LDL cholesterol produced an absolute reduction in major vascular events of about 1 percent during five years. This benefit was shown to greatly exceed statin risks. However, no prospective studies have been performed with the new risk calculator.
What are the risks of statins?
A slightly higher incidence of new diagnosis of diabetes has been identified, and this incidence is more likely with high-dose statins.3 Hepatic dysfunction is rare, and the U.S. Food and Drug Administration now recommends screening only before initiating statins.4
Myalgias are a vexing clinical problem, affecting up to 10 percent of those taking statins. Myalgias, weakness and serum creatine kinase concentrations usually return to normal days to weeks after statin drugs are discontinued.5 Guidelines suggest restarting at a lower dose or with an alternative statin after symptoms have resolved.
Do the guidelines recommend alternative risk stratification if we’re uncertain about the risk calculator?
Not specifically. Including family history of premature ASCVD, hsCRP, ABI and CT coronary artery calcification is weakly suggested as an additional method to help assess elevated risk of ASCVD.
What statin should be used at what dose?
The guidelines recommend high-intensity statin (atorvastatin, 40-80 mg or rosuvastatin, 20-40 mg) therapy for most patients who have indications for statins. Moderate-intensity statin (atorvastatin, 10-20 mg; rosuvastatin, 5-10 mg; simvastatin, 20-40 mg; pravastatin, 40-80 mg; or lovastatin, 40 mg) is recommended for patients 75 or older who have ASCVD; diabetics whose 10-year ASCVD risk is below 7.5 percent; and anyone who cannot tolerate a high-dose statin.