Concerns raised by two Harvard researchers over new treatment guidelines for heart risk shouldn’t change the method used for determining what patients should get cholesterol-lowering drugs, top U.S. heart doctors said today at the American Heart Association meeting in Dallas.
In a commentary set to run this week in the Lancet medical journal, Harvard University researchers Paul Ridker and Nancy Cook said a risk calculator designed to help doctors determine treatment needs might over-estimate by as much as 150 percent causing patients to be unnecessarily placed on drug treatment.
The calculator is only one determiner of treatment, said Sidney Smith, a professor of medicine at the University of North Carolina Chapel Hill who led development of the guidelines. Members of the heart group said they will update risk assessments as new data become available and will stick by the guidelines issued last week.
“We intend to move forward with the implementation of these guidelines,” Smith said. “It’s really important not to raise unnecessary alarm.”
The guidelines released by the American Heart Association and the American College of Cardiology last week will expand the use of statin drugs to almost 1 in 3 Americans from 16 percent currently. Everyone older than 40 with diabetes and those diagnosed with heart disease should be on a statin, regardless of their cholesterol count, the recommendations say.
That means as many as 15 million Americans will be told to start taking the drugs, a class of medicines including AstraZeneca Plc’s Crestor and generic drugs that can cost as little as 10 cents a day. Others may be weaned off treatments that work differently, such as Merck & Co.’s Zetia, that were prescribed to get them to the now abandoned targets for lower cholesterol. The guidelines also will ask more from patients, including an extra effort to improve their lifestyles through exercise, changes to diet and quitting smoking.
The new calculator could over-estimate the risk rates for some patients, though it would largely be for those who would be on a statin anyway, said Donald Lloyd-Jones, a member of the guidelines panel and a professor of medicine at Northwestern University’s Feinberg School of Medicine. Others that could be be affected are younger women with exceedingly low risk, he said. After a conversation with their doctors, which the guidelines recommend, those patients would typically not be put on a statin.
“We were aware during our validation processes that there could be some effective over-estimation of risk in some populations,” Lloyd-Jones said today at a news conference at the heart meeting in Dallas. “The truth is going to be somewhere in the middle. Over time we’re going to modify these risk scores so they get better and better, and we get closer to that goal of personalized medicine.”
The risk calculator is just one tool, the authors of the guidelines said. “You don’t simply mail out a prescription when you get a score,” Lloyd-Jones said. “That has to be put in context.”
The Harvard researchers argued that the inclusion of more recent studies would have lowered the calculations for what patients should be considered at greatest risk and needed to be on a statin. Using a different set of data than used by the AHA, Ridker and Cook found that the calculator over-estimated heart risk by 75 percent to 150 percent.
Ridker shared his concerns about the risk scores at the heart association’s annual meeting in Dallas on Nov. 16.
In a blog post today, Ridker said the changes he was calling for were relatively easy to make. He also said he supports the expanded use of statins recommended in the guidelines.
The “guidelines for statin therapy have taken several major steps forward that will greatly improve patient care,” Ridker said in a blog post. “Our patients need to go to the gym, throw out the cigarettes, and eat a healthier diet, but in addition to lifestyle, middle-age men and women need to talk to their physicians to see if they should also be on statin therapy.”
Smith and other panel members said the guidelines and risk tool would be updated as more long-term data on patients’ heart disease risk are generated.
“This is not computer medicine,” he said. “We’re using every tool possible to try and get the best care to our patients. As data do become available, you can expect to see us coming up with the best product.”
Heart disease and stroke are responsible for 1 in 3 deaths in the U.S., and 60 percent of Americans are expected to have a cardiovascular event in their lifetimes.