The American College of Cardiology (ACC) and the American Heart Association (AHA) released four prevention guidelines to reduce the risk of cardiovascular disease. The 2013 joint guidelines focus on cardiovascular risk assessment, lifestyle management, cholesterol treatment and managing overweight and obese adults.
The ACC and AHA collaborated with the National Lung, Heart, and Blood Institute (NHLBI) on the project, which evaluated evidence up to 2011. John G. Harold, MD, president of the ACC, and Mariell Jessup, MD, president of the AHA, described the guidelines as a bridge; expert panels are expected to update the guidelines beginning in 2014.
“They differ somewhat from our traditional AHA/ACC guidelines,” Jessup said at a press conference. “First, they are not an extensive compendium of clinical information. They are more limited in scope and focus on selected critical questions.”
Expert panels reviewed high-quality clinical trials and epidemiological studies, Jessup added. The guideline format combines the NHLBI and societies’ methods for determining strength of evidence.
The risk assessment and lifestyle management efforts were designed as support for the other initiatives. In that role, the risk assessment panel developed a quantitative tool that could be applied in clinical practice and be incorporated into guidelines and algorithms, said Donald Lloyd Jones, MD, co-chair of the risk assessment work group and chair of preventive medicine at Northwestern University Feinberg School of Medicine in Chicago.
The work group focused on three areas: new risk equations to predict atherosclerotic cardiovascular disease risk; additional risk markers that should be considered; and the value of adding longer-term (beyond 10-year) and lifetime estimations of risk.
In developing 10-year risk equations, they determined that the model should be broadened beyond traditional coronary heart disease events. “We realized quickly that we were leaving a lot of risk on the table by not including stroke in our risk assessment algorithm,” Jones said. “Stroke is a particularly important end point for women and African-Americans.”
Using updated data from population-based studies, they developed equations that include additional risk markers and represent the overall U.S. population. They also found evidence that longer-term or lifetime risk estimations help to identify younger patients who have no short-term risk but who have a high lifetime risk for developing cardiovascular disease.
“We’re hopeful that the equations can be programmed into electronic health platforms,” Jones said.
The lifestyle management panel re-evaluated and updated the concept of a healthy lifestyle as a way to prevent cardiovascular disease and modify risk factors. Recommendations include heart-healthy diets, physical activity and reductions in the intake of saturated fats, trans fats and sodium.
Guidelines on blood cholesterol treatment are designed to reduce atherosclerosis-related cardiovascular risk in adults. The guidelines focused on cholesterol-lowering therapies, looking at high-intensity and moderate-intensity approaches. “What our extensive literature review determined is that the evidence supported not only a heart-healthy lifestyle but the appropriate intensity of statin therapy,” said chair Neil Stone, MD, also of Northwestern University Feinberg School of Medicine.
The panel recommended physicians consider four factors: a history of MI or stroke; low-density lipoprotein (LDL) cholesterol level of 190 mg/dL or more; patients 40 to 75 years old with diabetes; and patients with a global cardiovascular risk assessment score of 7.5 percent or more.
The panel concluded that focusing on specific targets for LDL and non-high-density lipoprotein sometimes resulted in over or under treatment and recommended physicians instead use an appropriate intensity of statin therapy to reduce risk in patients most likely to benefit.
The obesity guidelines target five categories: people in need of losing weight; the range and benefits of weight loss; best dietary approaches; efficacy of lifestyle interventions; and benefits and risk of bariatric surgery in high-risk patients.
The experts recommended using current cut points for body mass index and waist circumference to identify patients at risk. They supported counseling patients with lifestyle changes because weight reductions, even on a modest scale, can improve health and reduce risk.
“We came down loud and clear that there is no ideal diet for weight loss and there is no superiority for any of the diets we examined,” said co-chair Donna Ryan, MD, professor emeritus at Louisiana State University’s Pennington Biomedical Research Center in Baton Rouge, La. “Our recommendation is that providers prescribe a diet to achieve reduced caloric intake as part of a comprehensive lifestyle intervention. What that diet looks like should be determined by the patient’s preferences and health status.”
The guidelines were published online Nov. 12 in Circulation and the Journal of the American College of Cardiology.