The American College of Cardiology (ACC) and the American Heart Association (AHA) released the latest version of their clinical practice guidelines for cardiovascular risk reduction on November 12, with key points including: no longer recommending specific target values for lipid therapy, recommending simultaneous assessment of 10-year and lifetime cardiovascular disease risk, and taking stroke into account when estimating cardiovascular disease risk.
The guidelines were authored by a lipid panel once known as the Adult Treatment Panel (ATP) IV. Inevitably, this lipid modifying treatment guideline will receive significant attention because it no longer recommends lowering low-density lipoprotein cholesterol (LDL-C) to a specific value, but instead uses drugs that have been shown to reduce cardiovascular disease and stroke risk according to the degree to which these risks are increased.
The panel concluded, “This guideline uses the intensity of statin therapy – rather than LDL-C or non-HDL-C target values – as the treatment target, based on a large body of evidence from randomized controlled trials that identifies moderate to high intensity statin therapy to safely reduce the risk of atherosclerotic cardiovascular events in four population groups.”
Dr. Neil J. Stone of Northwestern University’s Division of Cardiovascular Medicine, chair of the guideline writing committee, noted that the lipid-modifying therapy guideline brings “a new perspective on LDL and non-HDL cholesterol treatment targets” and identifies four groups of patients for whom moderate-to-high intensity statin therapy may be used as primary or secondary prevention. “Despite an extensive literature review, we were unable to find conclusive evidence to support the continued use of specific LDL-C and non-HDL-C treatment targets.”
Previous guidelines recommended LDL reduction to less than 100 mg/dl for those at high cardiovascular risk and to 70 mg/dl or less for very high-risk patients.
The series of clinical practice guidelines, originally revised under the auspices of the National Heart, Lung, and Blood Institute (NHLBI), was switched to the AHA and ACC in the first half of this year.ACC President John Gordon Harold, MD, of the David Geffen School of Medicine at the University of California, Los Angeles, described in a press release that, based on the best clinical trials since 2011 and In addition to lipid management, the “much-needed” guidelines focus on assessing cardiovascular risk, lifestyle changes to reduce cardiovascular risk, and management of overweight and obesity in adults, based on the best clinical trials and epidemiological studies since 2011.
Lipid Modification Therapy
Dr. Stone noted that the available evidence supports the use of “appropriate intensity” statin therapy to reduce risk based on a heart-healthy lifestyle. Four “key statin benefit groups” recommended for “high-intensity” statin therapy (reducing LDL by at least 50%) or “moderate-intensity” statin therapy (reducing LDL by approximately 30% to 49%) “These include.
・clinical atherosclerotic cardiovascular disease (ASCVD).
・Significantly elevated LDL-C to ≥190 mg/dl, including familial hyperlipidemia.
・Diabetes mellitus, age 40 to 75 years, without clinical ASCVD, and LDL levels between 70 and 189 mg/dl.
・No clinical ASCVD or diabetes, age 40 to 75 years, LDL levels between 70 and 189 mg/dl, and estimated 10-year ASCVD risk ≥7.5% (judged by calculating the overall cardiovascular risk score, using the formula proposed by the Risk Assessment Guidelines Working Group and incorporated into the guidelines).
”We believe that certain populations, such as those with a history of atherosclerotic events and very high LDL-C levels …… benefit most from high-intensity statin therapy, if they can tolerate it.” Dr. Stone noted, “For patients with a risk score ≥7.5% but who have not yet had a myocardial infarction (MI) or stroke, the analysis yielded strong evidence that treatment can stop or prevent these events and even reduce overall mortality in high-risk patients.”
The use of specific target values may often lead to under- or over-treatment of certain populations, such as the addition of drugs whose value of gain has not been proven. The available data do not support the use of a specific target value, but rather support clinicians to “apply the appropriate intensity of statin therapy to reduce the risk of atherosclerosis in patients most likely to benefit” and that non-statin therapy “does not provide an acceptable benefit in heart attack and stroke prevention compared to its adverse effects. Non-statin therapy “does not provide an acceptable CVD risk reduction benefit in heart attack and stroke prevention compared to its adverse effects”.
Cardiovascular Risk Assessment
Dr. Lloyd-Jones, co-chair of the editorial board and chair of the Department of Preventive Medicine at Northwestern University, noted that the guidelines for assessing cardiovascular risk in adults include a holistic risk assessment tool that “provides a quantitative clinical assessment to guide clinical care.
The guidelines recommend that lifetime risk be assessed along with 10-year risk. 10-year risk equations predict MI and stroke risk, whereas previous risk equations focused only on coronary event risk. risk,” which is particularly important in women and black patients.
Estimating lifetime risk may be particularly useful in identifying younger patients who have a low 10-year risk “but have unhealthy lifestyles or risk factors that place them at substantially higher risk of developing cardiovascular disease in the long term.
The risk equations for non-Hispanic whites and for blacks are based on data from NHLBI-funded population-based studies, including the Coronary Artery Risk Development in Young Adults Study (CARDIA), the Atherosclerosis Risk in Communities Study (ARIC), the Cardiovascular Health Study (CHS), and the Framingham Heart Study.
Use of these equations required input of age, sex, race, total cholesterol and HDL-C levels, blood pressure, antihypertensive treatment status, and current smoking and diabetes status. These were determined to be the best predictors of 10-year risk.
The investigators also considered other risk markers but did not include them in the equation due to insufficient supporting evidence. Until sufficient relevant data are available and risk prediction equations are developed for Hispanic, Asian, and Latino populations, risk equations for white males and females will be used for these ethnic groups for the time being.
Based on a review of the literature on novel risk markers, the working group concluded that if these equations do not yield definitive results, four markers “could be considered” to optimize risk assessment: family history of early-onset cardiovascular disease in first-degree relatives, coronary artery calcification score, high-sensitivity C-reactive protein (CRP) assay, and ankle brachial index test values.
There is insufficient evidence to support the use of other markers, and “we clearly oppose the use of carotid intima-media thickness measurements” because of evidence that the test does not provide additional benefit.
The guideline also describes how to integrate risk assessment into clinical practice, including an Excel spreadsheet that can be used to calculate risk. In addition, a risk equation can be compiled into an electronic health record.
Dr. John Rumsfeld, acting national director of cardiology for the Veterans Health Administration and professor of internal medicine at the University of Colorado, believes the new guideline’s recommendations on lipid-modifying therapy are a “course correction” rather than a fundamental change in direction.
”The guidelines are based on an objective evaluation of the evidence, and the evidence is clear: there is no evidence to support a specific lipid level as a therapeutic target. However, there is clear and strong evidence that statins should be used for those at elevated risk of heart disease and stroke. The new approach is more patient-centered; the treatment targets individuals most likely to benefit from long-term drug use; it focuses on reducing risk in these individuals with drugs that have definite effects; and the new approach also reduces patient burden by reducing repeated testing and the use of additional drugs with unproven effects.”
As early as 1 year ago, the Department of Veterans Affairs (VA) health care system moved away from reducing LDL-C to below 100 mg/dl as a national performance evaluation metric and instead adopted a performance evaluation metric similar to the new guideline recommendations, emphasizing the use of statins for patients at increased risk.
”The change from treatment attainment to risk reduction will reduce the use of unproven drugs to overtreat patients and may reduce the burden on patients and health systems from repeated blood tests and administration of additional medications.” Although clinicians can be initially surprised by the new guidelines, Dr. Rumsfeld believes they will readily accept the change in perception. Clinicians “will soon find that the new approach reflects the available evidence and can simplify clinical care.”
Managing Lifestyles to Reduce Cardiovascular Risk
Robert H. Eckel, MD, PhD, professor of internal medicine at the University of Colorado and another co-chair of the editorial board, noted that the other two guideline recommendations focus on lifestyle management and management of overweight and obesity, respectively. The lifestyle management guidelines recommend a heart-healthy dietary pattern that includes fruits, vegetables and whole grains, limits saturated fat, trans fat and sodium intake, and supplements dietary recommendations with appropriate physical activity.
Recommendations for physical activity are based primarily on the 2008 Department of Health and Human Services (DHHS) report, which supports 30 to 40 minutes of moderate to vigorous physical activity at least 3 to 4 days per week.
For those who would benefit from lower blood pressure, the new guidelines recommend a sodium intake of no more than 2,400 mg per day (the previous recommendation was no more than 3,600 mg per day for U.S. adults), while noting that a sodium intake of ≤1,500 mg per day is associated with a greater reduction in blood pressure.
Management of Overweight and Obesity in Adults
Dr. Donna Ryan of Louisiana State University, co-chair of the editorial committee, described the recommendations on the management of overweight and obesity in adults, which were developed in conjunction with the Obesity Society, as covering five major areas, including treatment algorithms for weight management, to help primary care physicians determine weight management options. The new guidelines can help primary care physicians determine which patients need to lose weight, how much weight they need to lose, the benefits of weight loss, optimal diets, the effectiveness of lifestyle interventions, and the benefits and risks of bariatric surgery.
Recommendations include the use of body mass index (BMI) as a “quick and easy first screening step” to identify patients at risk for obesity-related health problems and the use of waist circumference as an indicator of ASCVD risk, type 2 diabetes and all-cause mortality.
Because the ideal diet for weight loss has not yet been determined, clinicians should recommend a diet with a lower caloric intake, and the type of diet “should really be based on patient preferences and health status,” such as a low-calorie, low-sodium diet for overweight patients with hypertension.
Another recommendation is to adopt comprehensive weight loss measures, including diet and physical activity, with at least 6 months of counseling – ideally at least 1 year of counseling by a trained professional through on-site groups or individual counseling.
Bariatric surgery may be an option for patients with a BMI ≥ 35 kg/m2 with comorbidities, or a BMI ≥ 40 kg/m2. Although medication is a “key” area, the new guidelines do not make recommendations for medication for weight loss because sibutramine (which was withdrawn from the market) and orlistat were the only medications approved for weight loss in the United States when the new guidelines were first developed.