The AHA’s assessment of risk
The new guideline update recommends assessing each woman’s CVD risk and placing her into one of 3 risk groups—high risk, at risk, and ideal cardiovascular health (TABLE 3)—then using an algorithm to determine which preventive interventions to recommend based on her risk level.
This classification approach is challenging, for several reasons. It lumps women with markedly different risk profiles into the “at risk” group, a category that will likely apply to a high proportion of women. It also appears to encourage the use of diagnostic tests for subclinical vascular disease, for which there is no evidence of effectiveness. In addition, some of the terms used in the at-risk criteria, such as ”physical inactivity” and “poor diet,” are vague.
TABLE 3
Cardiovascular disease: How the AHA classifies women’s risk5
High risk ≥1 of the following: Documented CVD Diabetes Chronic or end-stage renal disease 10-year predicted risk of CVD ≥10%* |
At risk ≥1 of the following major risk factors: Smoking Hypertension (BP ≥120/80 mm Hg, or treated hypertension) Hyperlipidemia (total cholesterol ≥200 mg/dL, HDL cholesterol <50 mg/dL, or treated dyslipidemia) Obesity Poor diet Physical inactivity Premature CVD in a first-degree relative (<55 years for men and <65 for women) Metabolic syndrome Subclinical atherosclerosis Poor exercise tolerance on a treadmill test Systemic autoimmune disease A history of preeclampsia, gestational diabetes, or PIH |
Ideal cardiovascular health All of the following: Total cholesterol <200 mg/dL, untreated BP <120/80 mm Hg, untreated Fasting blood glucose <100 mg/dL, untreated BMI <25 mm/kg2 Nonsmoking Healthy diet (rich in fruits and vegetables; whole-grain, high-fiber foods; and fish, especially oily fish such as salmon and mackerel, at least twice a week; with limited intake of saturated fat, cholesterol, alcohol, sodium, and sugar; and avoidance of trans-fatty acids) Physical activity (≥150 minutes per week at moderate intensity or ≥75 minutes per week at vigorous intensity) |
| *Calculation tools can be found at http://hp2010.nhlbihin.net/atpiii/calculator.asp (for CHD) and at http://www.westernstroke.org/PersonalStrokeRisk1.xls (for stroke). AHA, American Heart Association; BMI, body mass index; BP, blood pressure; CVD, cardiovascular disease; HDL, high-density lipoprotein, PIH, pregnancy-induced hypertension. |
Some recommendations apply to all women, regardless of risk
The AHA recommendations for all women (TABLE 1) include smoking prevention or cessation, maintenance of optimal weight, regular physical activity, and a diet aimed at preventing CVD. The guidelines also emphasize that major CVD risks should be controlled, with either lifestyle and diet modifications (preferably) or pharmacotherapy. The aggressiveness of control targets depends on the level of risk and the presence of other risk factors.
The guidelines recommend against some interventions that are often used for CVD prevention, based on a high level of evidence that they are ineffective. These include estrogen or selective estrogen receptor modulators, antioxidant vitamins (vitamins E and C, and beta-carotene), folic acid with or without vitamins B6 and B12, and aspirin (for CHD prevention) for healthy women <65 years old.
The AHA does not take a position for or against several diagnostic and risk classification tools because of a lack of evidence of usefulness. These include CVD risk biomarkers such as high sensitivity C-reactive protein and imaging technologies such as coronary calcium scoring assessment.
AHA and USPSTF diverge, but not by much
Screening for conditions that increase CVD risk is not explicitly addressed in the AHA guidelines. Screening is implied by the proposed classification scheme, which includes the presence or absence of smoking, obesity, diabetes, hypertension, and dyslipidemia, but there is no guidance on when to start or stop screening for these conditions. The AHA and the USPSTF diverge on screening women for dyslipidemia, with the USPSTF recommending screening for lipid disorders only in women at increased risk for CHD.
The recommendations for optimal weight and activity levels in the AHA guidelines do not include advice on how to achieve them, nor do they call for an assessment of the effectiveness of behavioral counseling in the clinical setting. Because the USPSTF includes an assessment of, and recommendations for, asymptomatic patients in primary care settings, its recommendations do not address women with conditions such as established CVD, heart failure, or atrial fibrillation—which the AHA guidelines do.
Overall, the AHA and USPSTF agree more than they disagree, and each covers some areas that the other does not (TABLE 2). Family physicians can use the information provided by both entities to ensure that their female patients receive high-quality preventive care that will minimize their risk for CVD.