Substantial progress has been made in the awareness, treatment, and prevention of cardiovascular disease (CVD) in women since the first women-specific clinical recommendations for the prevention of CVD were published by the American Heart Association (AHA) in 1999.1 The myth that heart disease is a “man’s disease” has been debunked; the rate of public awareness of CVD as the leading cause of death among US women has increased from 30% in 1997 to 54% in 2009.2 The age-adjusted death rate resulting from coronary heart disease (CHD) in females, which accounts for about half of all CVD deaths in women, was 95.7 per 100 000 females in 2007, a third of what it was in 1980.3,4 Approximately 50% of this decline in CHD deaths has been attributed to reducing major risk factors and the other half to treatment of CHD including secondary preventive therapies.4 Major randomized controlled clinical trials such as the Women’s Health Initiative have changed the practice of CVD prevention in women over the past decade.5 The investment in combating this major public health issue for women has been significant, as have the scientific and medical achievements.
Despite the gains that have been made, considerable challenges remain. In 2007, CVD still caused ≈1 death per minute among women in the United States.6 These represent 421 918 deaths, more women’s lives than were claimed by cancer, chronic lower respiratory disease, Alzheimer disease, and accidents combined.6 Reversing a trend of the past 4 decades, CHD death rates in US women 35 to 54 years of age now actually appear to be increasing, likely because of the effects of the obesity epidemic.4 CVD rates in the United States are significantly higher for black females compared with their white counterparts (286.1/100 000 versus 205.7/100 000). This disparity parallels the substantially lower rate of awareness of heart disease and stroke that has been documented among black versus white women.2,6–8 Of concern is that in a recent AHA national survey, only 53% of women said the first thing they would do if they thought they were having a heart attack was to call 9-1-1. This distressing lack of appreciation by many women for the need for emergency care for acute cardiovascular events is a barrier to optimal survival among women and underscores the need for educational campaigns targeted to women.2
CVD rates in the United States are significantly higher for black females compared with their white counterparts (286.1/100 000 versus 205.7/100 000), which parallels the substantially lower rate of awareness of heart disease and stroke that has been documented among black versus white women.2,6–8 Each year, 55 000 more women than men have a stroke. Atrial fibrillation is independently associated with a 4- to 5-fold increased risk of ischemic stroke and is responsible for 15% to 20% of all ischemic strokes. It has been shown that undertreatment with anticoagulants doubles the risk of recurrent stroke; therefore, the expert panel voted to include recommendations for the prevention of stroke among women with atrial fibrillation.6,9,10
Adverse trends in CVD risk factors among women are an ongoing concern. After 65 years of age, a higher percentage of women than men have hypertension, and the gap will likely increase with the continued aging of the female population.6 The prevalence of hypertension in blacks in the United States is among the highest in the world, and it is increasing. From 1988 to 1994 through 1999 to 2002, the prevalence of hypertension in adults increased from 35.8% to 41.4% among blacks, and it was particularly high among black women at 44.0%.11
A very ominous trend is the ongoing increase in average body weight, with nearly 2 of every 3 US women >20 years of age now overweight or obese.6 The rise in obesity is a key contributor to the burgeoning epidemic of type 2 diabetes mellitus now seen in >12 million US women. Furthermore, the rate of diabetes mellitus is more than double in Hispanic women compared with non-Hispanic white women (12.7% versus 6.45%, respectively).6 The increasing prevalence of diabetes mellitus is concerning for many reasons, especially for its association with a greatly increased overall risk of myocardial infarction (MI) and stroke.12
The challenge of CVD in women is not limited to the United States. Recent data document the global scope of the problem: Heart disease is the leading cause of death in women in every major developed country and most emerging economies.13
Given the worldwide health and economic implications of CVD in women, there is strong rationale to sustain efforts to control major CVD risk factors and to apply evidence-based therapies in women.
In 2004, the AHA, in collaboration with numerous other organizations, expanded its focus on female-specific clinical recommendations and sponsored the “Evidence-Based Guidelines for Cardiovascular Disease Prevention in Women” and updated them in 2007.14,15 Initially, the guidelines challenged the conventional wisdom that women should be treated the same as men, primarily related to concerns about the lack of representation of women in clinical trials. As more women have participated in CVD research studies and more gender-specific analyses have been published, data have become available to make more definitive recommendations. Evolving science suggests that the overwhelming majority of recommendations to prevent CVD are similar for women and men, with few exceptions. Notably, aspirin is routinely recommended for the primary prevention of MI in men but not women.16,17 However, there is a growing appreciation that there may be gender differences in the magnitude of the relative and absolute potential benefits and risks of preventive interventions. The panel acknowledged unique opportunities to identify women at risk (eg, pregnancy) and addressed concerns that women often have more comorbidities and are older than men when they experience CHD.
The current guidelines encompass prevention of the scope of atherosclerotic thrombotic cardiovascular outcomes in women. However, it should be noted that the majority of data used to develop these guidelines is based on trials of CHD prevention. Future guidelines should consider recommendations for specific outcomes of particular importance in women, such as stroke. Each year, 55 000 more women die of stroke than men, and before 75 years of age. Stroke accounts for a higher proportion of CVD events than CHD in females, whereas the ratio is the opposite for males. Women have unique risk factors for stroke such as pregnancy and hormone therapy, have a greater prevalence of hypertension in older ages, a major risk factor for stroke, and may have different benefits and risks associated with interventions to reduce stroke risk compared with men.6 Atrial fibrillation is independently associated with a 4- to 5-fold increased risk of ischemic stroke and is responsible for 15% to 20% of all ischemic strokes. It has been shown that undertreatment with anticoagulants doubles the risk of recurrent stroke; therefore, the expert panel voted to include recommendations for the prevention of stroke among women with atrial fibrillation.6,9,10
Current systematic and critical review of the literature continues to update the guidelines, which have become the foundation to inform national educational programs for healthcare professionals and women consumers of healthcare. A major evolution from previous guidelines to the 2011 update is that effectiveness (benefits and risks observed in clinical practice) of preventive therapies was strongly considered and recommendations were not limited to evidence that documents efficacy (benefits observed in clinical research); hence, in the transformation from “evidence-based” to “effectiveness-based” guidelines for the prevention of cardiovascular disease in women, the panel voted to update recommendations to those therapies that have been shown to have sufficient evidence of clinical benefit for CVD outcomes. Class III recommendations from prior guidelines that are not recommended for use for the prevention of CVD (Table 1) were retained as no new evidence has become available to alter the recommendations. The list of Class III recommendations is not exhaustive, and therapies that were previously searched were based on those preventive interventions commonly believed to have a potential benefit for the prevention of CVD in women despite a lack of definitive clinical trial evidence of benefit. Uses of medications for indications beyond the prevention of ischemic CVD are not addressed in this document. Use of medications for indications beyond the prevention of ischemic CVD is not addressed in this document and can be found elsewhere (www.heart.org). Some interventions (eg, screening for depression) were recognized to lack data on direct CVD outcomes benefit but were included in an algorithm for approaches to the evaluation of women because they may indirectly impact CVD risk through adherence to prevention therapies or other mechanisms (Figure). The expert panel also recognized that cost-effectiveness, which may differ by sex, needed to be addressed; thus, a comprehensive review of current literature on the topic has been added. The guidelines continue to prioritize lifestyle approaches to the prevention of CVD, likely the most cost-effective strategy. The panel also acknowledged that difficulty in adhering to lifestyle and medical recommendations limits effectiveness; therefore, new sections were added on guideline implementation.