Rodney Hayward, MD, is an alumnus and co-director of the Robert Wood Johnson Foundation (RWJF) Clinical Scholars program (1986-1988), a professor at the University of Michigan, a senior Veteran’s Administration (VA) investigator, and the lead author of several studies about the way we measure heart disease risk. His research is the basis for American Heart Association (AHA) and American College of Cardiology’s (ACC) new approach to evaluating heart disease through a host of factors, instead of a simple cholesterol score. Here, he explains the current controversy over this new risk calculation and why he does not completely agree with the new recommendations
Q: What did you and your research partner, Harlan Krumholz, MD, co-director of the RWJF Clinical Scholars program at Yale University, discover that led to the rewriting of the national cholesterol guidelines?
A: We found that the currently used measures of high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol were not an accurate way to determine how much an individual would benefit from taking statins to reduce their heart attack risk. But, we do know that when properly prescribed, statins can dramatically reduce cardiovascular events and mortality.
To know how much a person will benefit from statins, you need to know a person’s risk of developing heart disease or dying from it in the absence of treatment and the degree to which the treatment can reduce that risk. The fact that a person has a cholesterol level of 200, for example, cannot tell us that.
Q: What factors are being considered in the new guidelines?
A: The score considers whether a person smokes, is diabetic, has good cholesterol levels, has kidney disease, as well as an individual’s age, sex, and family health history.
Q: There is some controversy over the accuracy of the new cardiovascular disease risk assessment tool. Are you in agreement with the panel’s recommendations?
A: I would say this is the one area in which I do not agree with the panel. They originally recommended that everyone who scored 7.5—representing a 7.5 percent risk of a heart attack in a 10-year period—take statins. We do not agree that 7.5 is the magic number for every person. The evidence does not suggest that treating people with this score is beneficial.
We think the best predictor would be the person’s comprehensive risk, as assessed and discussed with their physician. My personal risk, for instance, is estimated at 8 percent and I do not plan to take statins unless my risk gets to 12 to 15 percent. As your risk number goes up, your chances of benefiting from statins multiplies. Also, these risk estimates are never exact.
Q: What’s the problem with the risk calculation and what changes are being considered?
A: Concerns have been raised that the proposed risk calculator systemically over-estimates risks. For example, the calculator might estimate a person’s 10-year risk of a heart attack or stroke at 8 percent when it should be 5 percent. It is unclear who is correct at this time. I believe a more important lesson here is that we should no longer be recommending that all doctors use the same risk calculator. For example, Kaiser has developed a risk tool developed and validated on Kaiser patients, and the VA is doing the same thing. All the evidence suggests that this can be a much more accurate approach. In the era of modern IT, we can and should be calibrating tools to the specific populations we are serving.
Q: When do you think we will have an answer and a new way to address statin use?
A: That is hard to tell. These processes tend to take time. I’m sure that the ACC/AHA committee will try their best to not keep the public waiting, but they also want to be sure that they address all the issues raised.
The basic approach to statin therapy is in place, however, which is a major step forward. Still, our hope is that the committee revises the guidelines to acknowledge a gray zone—a level of patient risk at which the accuracy of risk prediction and the expected benefits from a statin are not great enough to strongly recommend that the person take or not take a statin. Within this range, a person who is very concerned about a potential heart attack might decide to start one, but another who has strong feelings about not taking any medication unless absolutely necessary might reasonably decide to not take one yet. There are always gray zones in life, and it’s time for medical guidelines to recognize this.
Q: Are there side effects associated with statin use?
A: The most common side effect is muscle aches. Recent research also shows they may reduce the benefits of exercise or increase a person’s risk of developing type 2 diabetes. Therefore, if your heart disease risk is low, I do not feel that it’s worth taking the drugs and dealing with the potential side effects.
The larger issue is that we only have data on the side effects related to 10 years of statin use. We do not know what happens if a person stays on statins for 20 years or more.
Q: You said that you would suggest people talk to their doctors about other types of heart disease prevention if they are low on the risk scale or at 7.5. What do you suggest?
A: Do not be sedentary. Exercise at a brisk pace for at least two and one half hours a week, and keep your weight under control. Consider what you eat—nuts, olive oil, fish oil, canola oil can reduce your risk of heart attack by roughly a third. And do not smoke. Avoiding smoking is probably the most important thing you can do to have a healthy heart.