The 2013 American College of Cardiology/American Heart Association Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults and Guideline on the Assessment of Cardiovascular Risk were released in mid-November 2013. This article explains the guidelines, the risk equations, and their derivations, and addresses criticisms so that practicing physicians may be more comfortable in using the guidelines and the risk equations to inform patients of their atherosclerotic cardiovascular risk and choices to reduce that risk. The article also addresses patient concerns about statin safety if lifestyle changes have been insufficient to reduce their risk.

Keywords

2013 ACC/AHA cholesterol guidelines

Pooled cohort equations

Ten-year ASCVD risk

Statin therapy

Primary prevention of ASCVD

Blood cholesterol guideline

Cardiovascular risk guideline

Key points

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality, accounting for every 1 in 3 deaths in the United States.1 Over the last decade, death rates attributable to CVD declined 31.0% and the number of CVD deaths per year declined by 16.7%. Death rates in 2010 attributable to stroke and coronary heart disease (CHD) were 39.1 and 113.6 down from 60.9 (−33%) and 186.8 (−36%) per 100,000 in 2000, respectively. In diabetic patients from 1990 to 2010 acute myocardial changes decreased 67.8%, stroke 52.7%, and amputations 51.4%.2 However, in 2010, CVD still accounted for 31.9% of all deaths in the United States. A recent report from a national American clinical laboratory (Quest) reported on low-density lipoprotein (LDL) cholesterol (LDL-C) levels in 150 million Americans from 2000 to 2011. Although there was a steady decline from 2000 to 2008, LDL-C levels remained the same from 2008 to 2011, with no change in the percentage achieving any LDL-C goal levels, including levels less than 100 mg/dL.3

On 13 November, 2013, the Joint Task Force of the American College of Cardiology (ACC) and the American Heart Association (AHA) published new atherosclerotic CVD (ASCVD) prevention guidelines as an update to the 2008 guidelines developed by the National Heart, Lung, and Blood Institute.4 This article restates the guidelines in a simpler format than the original synopsis5 and discusses further the new risk equations that can help physicians and patients make decisions on lifestyle and medications to significantly reduce patients’ lifetime risks of ASCVD.

Paradigm shift from treat-to-target to intensity of statin therapy

For more than a decade, physicians have targeted LDL-C and non–high-density lipoprotein (HDL) cholesterol (non–HDL-C) goals by frequent laboratory testing, adjusting intensity of statin therapy, and using therapeutically unproven combinations of lipid-altering medication added to statin therapy. Unlike Adult Treatment Panel III (ATP-III) guidelines and the recent European and Canadian guidelines, the updated guidelines abandon these targets and recommend treating cholesterol by prescribing the appropriate intensity of statin therapy for those patients who are most likely to benefit. The panel’s decision for this recommendation is based on a rigorous systematic review of randomized controlled trials (RCTs), a few of which are listed in Table 1; systematic reviews; and meta-analyses (Table 2) rather than fewer RCTs and expert opinion, which were used by the ATP-III guidelines. The recommendation is to measure LDL-C at baseline and rule out severe hypertriglyceridemia (≥500 mg/dL), reassess LDL-C 1 to 3 months after statin initiation and every 3 to 12 months thereafter to check for compliance (ie, the stability of the expected percentage decreases in LDL-C). Routine monitoring of alanine aminotransferase (ALT) or creatine phosphokinase (CPK) is no longer recommended in asymptomatic patients. This recommendation translates into less frequent laboratory testing, fewer dose adjustments, and less use of combination lipid therapy.