What Do the 2011 American Heart Association Guidelines Tell Us About Prevention of Cardiovascular Disease in Women?

Abstract

The 2011 Update of the American Heart Association's Cardiovascular Disease Prevention Guideline for Women is designed to help women and their physicians understand cardiovascular Disease (CVD) risks and undertake practical steps that are most effective in preventing heart disease and stroke. Defining a woman's risk status and improving her adherence to preventive lifestyle behaviors and medications is the best strategy to lower the burden of CVD in women. © 2011 Wiley Periodicals, Inc.

The author has no funding or financial relationships of interest to disclose. Author is also author of the Guideline.

Coronary heart disease remains the leading cause of mortality for US women,1 as well as for women in most industrialized and emerging‐economy nations.2 Although >80% of the cardiovascular disease (CVD) burden occurs in low‐ and middle‐income nations, risk‐factor data from these countries are sparse. Concomitant with the widespread educational and awareness campaigns regarding heart disease in women in the United States,3 cardiovascular mortality among US women has decreased dramatically each year since 2000; the 2007 cardiovascular mortality rate in women represents a 43% reduction from the 1997 rate. Half of this decline reflects the improved management of established CVD; the remainder is attributable to reductions in major coronary risk factors.

Nonetheless, about half of US women remain unaware of their cardiovascular risk, with lack of awareness predominant in high‐risk subsets, such as women of racial and ethnic minorities.3, 4, 5 Physicians and other healthcare providers continue to underestimate cardiovascular risk for women, with consequent underutilization of preventive therapies.6, 7, 8

The 2011 Update9 to the American Heart Association Effectiveness‐Based Guidelines for Prevention of Cardiovascular Disease in Women is designed to highlight the evidence basis for control of major cardiovascular risk factors in women and to encourage application of effective therapies. Additionally, the Guidelines have been transformed from an evidence‐based to an effectiveness‐based approach. An evidence‐based approach documents the benefits observed in clinical research studies, whereas an effectiveness‐based approach also encompasses the benefits and risks observed in clinical practice (ie, therapies shown to have sufficient evidence of clinical benefit for CVD outcomes for women).

Cardiovascular Disease Risk Assessment

The Framingham Risk Score traditionally underestimates CVD risk in women, likely owing to its focus on intermediate‐term (ie, 10‐year) risk and on myocardial infarction (MI) and coronary death, as well as omitting consideration of family history. The 2007 Guidelines promulgated a novel algorithm allowing the physician to simplify risk stratification of women to reflect their higher lifetime risk for CVD, which approximates 1 in 2. Addressing CVD, rather than solely coronary heart disease, incorporates the concept of increased stroke risk among younger women. The 2007 algorithm has been validated in a contemporary clinical population10 and, with modest modifications, is presented in the 2011 Update (Table 1).

Table 1.

Classification of CVD Risk in Women

Risk Status	Criteria
High risk (≥1 high‐risk states)	Clinically manifest CHD
	Clinically manifest cerebrovascular disease
	Clinically manifest peripheral arterial disease
	Abdominal aortic aneurysm
	End‐stage or chronic kidney disease
	Diabetes mellitus
	10‐y Predicted CVD risk ≥10%
At risk (≥1 major risk factor[s])	Cigarette smoking
	SBP ≥120 mm Hg, DBP ≥80 mm Hg, or treated hypertension
	Total cholesterol ≥200 mg/dL, HDL‐C <50 mg/dL, or treated for dyslipidemia
	Obesity, particularly central adiposity
	Poor diet
	Physical inactivity
	Family history of premature CVD occurring in first‐degree relatives in men <55 y of age or in women <65 y of age
	Metabolic syndrome
	Evidence of advanced subclinical atherosclerosis (eg, coronary calcification, carotid plaque, or thickened IMT)
	Poor exercise capacity on treadmill test and/or abnormal heart rate recovery after stopping exercise
	Systemic autoimmune collagen‐vascular disease (eg, lupus or rheumatoid arthritis)
	History of preeclampsia, gestational diabetes, or pregnancy‐induced hypertension
Ideal cardiovascular health (all of these)	Total cholesterol <200 mg/dL (untreated)
	BP <120/<80 mm Hg (untreated)
	Fasting blood glucose <100 mg/dL (untreated)
	Body mass index <25 kg/m2
	Abstinence from smoking
	Physical activity at goal for adults >20 yrs of age: ≥150 min/wk moderate intensity, ≥75 min/wk vigorous intensity, or combination
	Healthy (DASH‐like) diet

CVD Indicates cardiovascular disease; CHD, coronary heart disease; SBP, systolic blood pressure; DBP, diastolic blood pressure; HDL‐C; high‐density lipoprotein cholesterol; IMT, intima‐media thickness; BP, blood pressure; and DASH, Dietary Approaches to Stop Hypertension.

Source: Mosca, Circulation 2011;123:1243.

Women are classified as “high risk,” “at risk,” and as at “ideal cardiovascular health.” High‐risk status characterizes women with clinical evidence of coronary heart disease, cerebrovascular disease, peripheral arterial disease, and abdominal aortic aneurysm; those with the coronary risk equivalents of chronic kidney disease and diabetes mellitus (DM); and those with a 10‐year predicted cardiovascular risk of ≥10%.

At least 1 major risk factor is used to define the population of “at risk” women. These risk factors include cigarette smoking, hypertension, dyslipidemia, obesity, poor diet, physical inactivity, a family history of premature CVD, and the metabolic syndrome. Important added characteristics include evidence of subclinical atherosclerosis such as coronary calcification, carotid plaque, or intima‐media thickening; poor exercise capacity on treadmill testing and/or abnormal heart rate recovery after termination of exercise; and evidence of systemic autoimmune collagen‐vascular disease, because of its significant increased relative risk for CVD.11 Women with these “at risk” disorders should be screened for cardiovascular risk factors. Newly added is a history of pregnancy complications, including preeclampsia, gestational diabetes, or pregnancy‐induced hypertension; these abnormalities are responses to the cardiovascular and metabolic stress of pregnancy and appear to be early indicators of cardiovascular risk.12, 13, 14 Appropriate referral of such women by the obstetrician/gynecologist for risk factor assessment and surveillance is warranted, and a detailed history of pregnancy complications should be part of the routine cardiovascular risk factor assessment of all women.15, 16, 17

The new concept of “ideal cardiovascular health” encompasses absence of clinical CVD and ideal levels of total cholesterol, blood pressure, and fasting blood glucose, with adherence to heart‐healthy behaviors including a lean body mass index (BMI), smoking abstinence, participation in physical activity at recommended goals, and a healthy diet (similar to the Dietary Approaches to Stop Hypertension [DASH] diet).18 Despite interest in novel risk factors and risk markers, as well as novel imaging technologies, none are currently globally recommended for the risk stratification of women,19 although these variables remain topics of intensive research.

Although interventions such as screening for depression in CVD women lacked data on direct CVD outcomes, they were included in the evaluation algorithm as they may directly impact CVD risk through adherence to preventive therapies or other mechanisms.

Thus, the recommended evaluation of cardiovascular risk in women encompasses a medical history, family history, and history of pregnancy complications; assessment of symptoms of CVD; and depression screening for women with documented CVD. Physical examination should include blood pressure, BMI, and waist size; laboratory tests should include fasting lipoprotein and glucose levels; and a Framingham risk assessment should be included if there is no evidence for CVD, chronic kidney disease, or DM.

Guidelines for the Prevention of Cardiovascular Disease in Women

As in the 2007 Guidelines, interventions are characterized as lifestyle recommendations that apply to all women, major risk interventions that vary by risk status, and preventive drug interventions that comparably vary by individual risk status. The Guidelines continue to highlight lifestyle approaches to CVD prevention as likely the most cost‐effective and widely applicable strategy.

Lifestyle Interventions

Lifestyle interventions include smoking cessation and avoidance of environmental tobacco smoke. Regular physical activity is recommended at a goal of ≥115 minutes of moderate exercise weekly, or 75 minutes of vigorous exercise weekly. Muscle‐strengthening activities are recommended, as is an increased duration of physical activity for weight loss or to sustain weight loss.

Cardiac rehabilitation is recommended for women with a recent coronary or cerebrovascular event, new‐onset or chronic angina, peripheral arterial disease, or current/prior symptoms of heart failure and a left ventricular ejection fraction (LVEF) ≤35%.

The recommended dietary intake is one rich in fruits and vegetables, with whole‐grain, high‐fiber foods; consumption of fish at least twice weekly; limited intake of saturated fat, cholesterol, alcohol, sodium, and sugar; and avoidance of trans‐fatty acids. Weight maintenance or loss should be achieved through a combination of physical activity, caloric intake, and behavioral programs, designed to achieve a BMI <25 kg/m² and a waist size <35 inches for US women.

Consumption of omega‐3 fatty acids in the form of fish or capsule may be considered for women with hypercholesterolemia and/or hypertriglyceridemia.

Major Risk Factor Interventions

The optimal blood pressure of <120/80 mm Hg should be encouraged through lifestyle approaches, including weight control, increased physical activity, sodium restriction, alcohol moderation, and increased consumption of fruits, vegetables, and low‐fat diary products. Pharmacotherapy is indicated when the blood pressure is ≥140/90 mm Hg (or ≥130/80 mm Hg with chronic kidney disease or DM). Initial therapy for blood pressure control of high‐risk women with acute coronary syndrome or MI should include β‐blockers and/or angiotensin‐converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARBs).

Optimal lipid and lipoprotein levels should be encouraged through lifestyle approaches and encompass a low‐density lipoprotein cholesterol (LDL‐C) <100 mg/dL, high‐density lipoprotein cholesterol (HDL‐C) >50 mg/dL, triglycerides <150 mg/dL, and non–HDL‐C (total cholesterol − HDL‐C) <130 mg/dL. High‐risk women should have LDL‐C–lowering pharmacotherapy simultaneous with lifestyle interventions to achieve an LDL‐C <100 mg/dL, with reduction to <70 mg/dL reasonable for very‐high‐risk women. For the “at risk” woman, the intensity of the LDL‐C–lowering goal varies with the risk factor burden. Pharmacotherapy with niacin or fibrates for low HDL‐C or elevated non–HDL‐C can be useful in high‐risk women following attainment of their LDL‐C goal.

For the woman with DM, both lifestyle and pharmacotherapy are designed to achieve a glycated hemoglobin <7% if this can be accomplished without significant hypoglycemia.

Preventive Drug Interventions

Aspirin should be used in high‐risk women at a dosage of 75–325 mg daily, unless contraindicated, and is reasonable for women with DM. For other “at risk” or healthy women, aspirin can be useful in those age ≥65 years (81 mg daily, or 100 mg every other day) if the blood pressure is controlled and the benefit for ischemic stroke and MI prevention is likely to outweigh the risk of gastrointestinal bleeding and hemorrhagic stroke. It may also be reasonable for women age <65 years to prevent ischemic stroke.20, 21

Aspirin should be used in women with chronic or paroxysmal atrial fibrillation with a contraindication to warfarin therapy or at low stroke risk. For women with chronic or paroxysmal atrial fibrillation, warfarin should be used in those not at low risk for stroke to maintain an international normalized ratio of 2–3; dabigatran is a useful alternative to warfarin in the absence of a prosthetic heart valve, hemodynamically significant valve disease, or severe renal or liver disease.22

Women at high risk should receive β‐blocker23 and ACE inhibitor24 therapy unless contraindicated following MI and in those with clinical evidence of heart failure, LVEF ≤40% or DM; ARBs should be used in women intolerant of ACE inhibitors. Aldosterone‐blocking agents after MI are indicated in women who do not have significant hypotension, renal dysfunction, or hyperkalemia already receiving a β‐blocker and ACE inhibitor who have an LVEF ≤40% and symptoms of heart failure.25

Interventions Not Recommended

The class III recommendations (those not useful/effective and that may be harmful for the prevention of CVD in women) have not changed since the 2007 Guideline. Interventions to be avoided for cardiovascular prevention are menopausal hormone therapy,26, 27, 28 antioxidant vitamin supplements,29, 30 folic acid with or without vitamin B6 and B12 supplementation,31 and aspirin for prevention of MI in women age <65 years.20

Patient Education, Communication, and Patient Adherence

Optimal adherence to CVD‐prevention guidelines for women requires strategies to improve patient, clinician, and systemic barriers to adherence. The evidence base for methods to improve adherence is sparse, but with increasing patient and clinician knowledge of the importance of CVD prevention in women, improvements have occurred in CVD risk factor awareness, treatment, and control.32 The goal is improved cardiovascular health in women and reduction in death and disability from CVD and stroke.

Challenges to successful patient education include the limited time available for healthcare visits, patients with complex comorbidities, lack of personnel for teaching and training, lack of training in counseling patients about behavioral change, and reimbursement issues.33 Specific patient populations at risk for nonadherence include women with low socioeconomic status, low literacy level, depression and other psychiatric illnesses, older age, poor hearing or vision, poor cognitive function, lack of fluency in English, and selected cultures and religions that limit confidence in Western medicine.9

Summary

Lifestyle recommendations of smoking cessation, a DASH‐like diet, regular physical activity, and weight management are indicated for all women.

For the woman at high risk of CVD, priorities include blood pressure control, therapy to lower LDL‐C to at least <100 mg/dL, β‐blocker therapy, and ACE inhibitor/ARB therapy. Also to be considered are therapy to lower LDL‐C with a goal of <70 mg/dL for very‐high‐risk women; therapy to lower non‐HDL‐C with a goal of <130 mg/dL in very‐high‐risk women with recent acute coronary syndrome or multiple poorly controlled risk factors; glycemia control in diabetic women; aspirin/antiplatelet agents; and omega‐3 fatty acids.

For the “at risk” woman, the initial recommendations following lifestyle implementation are for blood pressure control and therapy to lower LDL‐C to ≤190 mg/dL. To be considered are therapy for high LDL‐C, non–HDL‐C, and triglycerides and/or HDL‐C in select women. Also to be considered is aspirin therapy.