A Yale University study has found that new national guidelines can improve the way statin drugs are prescribed to patients at risk for cardiovascular disease.
The research, published Aug. 25 in the Journal of the American College of Cardiology
, also showed the new guidelines produce only a modest increase in the number of patients being given the drugs.
Statins are a class of drugs that help lower cholesterol by blocking the enzyme HMG-CoA reductase, which the body needs in order to produce cholesterol. Common statin medications include Lipitor, Levacor, Zocor, Pravachol, and Crestor.
In 2013, the American Heart Association and the American College of Cardiology jointly published a new set of standards for the assessment of cardiovascular risk. The standards replaced the 2001 National Cholesterol Education Program Adult Treatment Panel III recommendations.
"There has been a great deal of discussion about the new guidelines. People worry whether the new risk equation is accurate," said Dr. Kevin M. Johnson, lead author of the study and associate professor of diagnostic radiology at the Yale School of Medicine. "They are concerned that too many people will be put on statins."
Johnson and co-author Dr. David A. Dowe of Atlantic Medical Imaging, in Galloway, N.J., studied 3,076 subjects. They applied both sets of guidelines to determine whether patients would start statin therapy.
They found that the new guidelines did a better job of discriminating between patients with little or no plaque and those with more plaque. Of patients with heavy plaque, 92% would be assigned to statin therapy under the new method, but only 53% under the old standards.
The biggest difference between the two results, researchers said, was the use of low-density lipoprotein (LDL) cholesterol targets under the old guidelines. The targets "seriously degraded the accuracy of the NCEP guideline for statin assignment," according to the study.
"The old guidelines emphasized lowering LDL cholesterol to certain target values, but the new guidelines have done away with that approach," Johnson said. "Many doctors are reluctant to give up targets."
Overall, 15% more patients would be put on statins under the new guidelines — considerably fewer than some observers had predicted, he added.
The researchers noted that they used coronary atherosclerotic plaque burden as the determining factor in the study, rather than cardiac events. Further study will be necessary to evaluate the guidelines with outcome data.