Cardiovascular disease (CVD) caused by atherosclerosis continues to be the leading cause of death and is a major cause of disability as well as a significant source of healthcare costs in the United States. In 2013, the American College of Cardiology (ACC) and the American Heart Association (AHA) released an updated clinical practice guideline to help clinicians better identify adults who may be at high risk for developing atherosclerotic CVD. The update, published jointly in the Journal of the American College of Cardiology and Circulation, also provides recommendations for identifying patients who could benefit from lifestyle changes or drug therapy to help prevent CVD.
“These guidelines were last updated about 10 years ago,” says David C. Goff, Jr., MD, PhD, who co-chaired the ACC/AHA risk assessment guideline writing group. “Since that time, we have collected a large amount of research that has further enhanced our understanding of how best to care for these patients and improve our approaches to determining who should get specific types of preventive treatments.”
A key goal of the ACC/AHA guideline is to ensure that preventive treatments—especially lifestyle changes and drug treatment—are used in those who are most likely to benefit from them. To do this, the guideline includes high-quality risk assessment methods that use risk factors that are known to lead to atherosclerosis (Table 1). Factors such as age, cholesterol levels, blood pressure, smoking, and diabetes can be easily collected by clinicians and then integrated into a risk score to guide care and prompt discussions with patients.
“The vast majority of heart attacks and strokes could be prevented if patients knew their risk and took actions to reduce that risk,” explains Dr. Goff. “That action starts with adopting a healthy lifestyle. For some patients at higher risk, it also includes medications. Unfortunately, both patients and physicians often underestimate CVD risk, especially when considered over a lifespan.” The recommendations offer clinicians the most up-to-date, comprehensive guidance and an algorithm about assessing risk so they can work with patients to prevent heart attacks and stroke.
According to Dr. Goff, about one in three U.S. adults who have not yet been diagnosed with CVD and have not had a heart attack or stroke are at high enough risk that they could benefit from primary prevention with medications, most notably statins, to lower their risk. “The recommendations help clinicians recognize which patients are candidates for statins for both primary and secondary prevention,” he says. “For primary prevention, the information on risk helps physicians identify patients who should be considered for statin therapy to prevent heart attacks and strokes.”
The ACC/AHA guideline has also been broadened to include assessment for risk of stroke. “By including stroke in the algorithm, we can better calculate overall cardiovascular risk,” Dr. Goff says. “This is especially important for women and African Americans at high risk for stroke.” In the past, cardiovascular risk assessment included only coronary heart disease. Furthermore, the recommendations help clinicians and patients look beyond traditional short-term (10-year) risk estimates to predict lifetime risk of developing heart disease and stroke.
“The vast majority of heart attacks and strokes could be prevented
if patients knew their risk and took actions to reduce that risk.”
There is some evidence that the known risk factors have somewhat different effects on certain genders and races. The guidelines provide new gender- and ethnicity-specific formulas for predicting risk in African-American and non-Hispanic Caucasian women and men. The algorithm allows clinicians to be selective about whose risk for CVD is high enough that it would merit considering drug therapy to help prevent it.
Newer Risk Measures
The ACC/AHA work group also provided recommendations about the clinical usefulness of newer markers of risk. These measures include family history of premature CVD, coronary artery calcium scores, high-sensitivity C-reactive protein levels, and ankle brachial index (Table 2). While these measures are not recommended for routine use in risk assessment, they have stood out as potentially helpful in some cases. “These measures have shown the greatest promise,” says Dr. Goff. “They may help inform treatment decision making when patients or providers are on the fence after quantitative risk assessment.”
The risk for developing atherosclerosis accrues over time and is a function of lifelong exposure to risk factors. Accordingly, Dr. Goff says it is never too early for clinicians to focus on determining risk. “It’s hoped that these algorithms will be incorporated into electronic health records to help clinicians easily and automatically calculate risk,” he says. “In turn, clinicians can be prompted to discuss individualized options for lowering risks. In the future, it’s anticipated that more research will provide an even better understanding of the optimal means for using short- and long-term cardiovascular risk assessment in all race and ethnic groups, across different ages, and between men and women.”
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