Tremendous strides have been made in the awareness, treatment, and prevention of cardiovascular disease (CVD) among women since the first guidelines for the prevention of CVD in women were published by the American Heart Association (AHA) in 1999. Despite these advances, CVD remains the leading cause of death among women in the United States, and rates are alarmingly high among women aged 35 to 54. Each year, 55,000 more women than men suffer a stroke, and the rates of obesity and diabetes continue to rise in women. To keep up with emerging data, the AHA updated its guidelines for preventing CVD in women in the March 22, 2011 issue of Circulation.
A major evolution from previous guidelines in the 2011 update is that both efficacy and effectiveness of preventive therapies were considered. “These are real-world guidelines that take into account the efficacy of a recommendation—what has been proven through clinical research—and the effectiveness—what is experienced in practice,” explains Lori J. Mosca, MD, MPH, PhD, FAHA, who chaired the AHA expert panel that developed the guidelines. Women treated in clinical practice are often older, sicker, and have more comorbidities when compared with those who participate in clinical trials. As such, side effects, cost implications, and absolute net benefits of therapies may be different in the research setting than in the practice setting. “Health professionals need to balance the benefit-to-risk ratio as well as the likelihood of adherence in the real-world setting. All these factors should be taken into consideration when making decisions about preventive therapy.”
“Women are more likely to experience stroke relative to myocardial infarction when compared with men. By excluding stroke risk, we can overlook many components of cardiovascular risk.”
CVD Risk Assessment
The risk classification scheme that the AHA expert panel recommended has changed with regard to pregnancy complications and the threshold for what is now considered high risk (Table 1). “Pregnancy complications—meaning a history of gestational diabetes, preeclampsia, bleeding in the third trimester, preterm birth, or small for gestational age—are associated with an increased risk of CVD,” says Dr. Mosca. “Having preeclampsia, in particular, doubles a woman’s risk of having a heart attack or stroke in the next 10 to 15 years.” The expert panel emphasized the importance of identifying women with pregnancy complications as having early indicators of increased CVD risk so that more aggressive interventions can be initiated early. If these conditions are identified, physicians are recommended to maintain follow-up after pregnancy and address CVD risk accordingly.
The threshold for what is considered “high risk” based on Framingham risk scores has been adjusted with an increased emphasis on stroke. In 2007, high risk was defined as a 10% or higher 10-year coronary heart disease (CHD) risk. Now, high risk is defined as a 10% or higher 10-year risk for all CVD, not just CHD alone. “We now have evidence suggesting that global risk derived from the Framingham score underestimates cardiac risk in women,” explains Dr. Mosca. “There are also gender differences in cardiovascular outcomes. Women are more likely to experience stroke relative to myocardial infarction when compared with men. By excluding stroke risk, we can overlook many components of cardiovascular risk.” She added that the expert panel did not change any of the guidelines for lipid management. They are still based on a 10% or higher 10-year risk for CHD according to Framingham risk score.
Major Guideline Changes
Women have unique risk factors for stroke, including pregnancy, hormone therapy, hypertension, and atrial fibrillation (AF). To address this, the expert panel included recommendations for the prevention of stroke among women with AF. “There is also a recommendation for dabigatran, a new alternative to warfarin for women with chronic or paroxysmal AF,” Dr. Mosca says. “This could potentially improve compliance with the recommendations to prevent stroke in the setting of AF.”
The 2011 AHA update recognizes the importance of autoimmune disorders (eg, lupus and rheumatoid arthritis) because they can be early indicators of potential heart problems. The panel also highlighted the prevalence of depression in women and its association with non-adherence to CVD prevention guidelines. Physicians are encouraged to screen for depression and refer appropriately, although it has not been shown to alter CVD outcomes directly. Doing so may have an impact on adherence to the other preventive guidelines that have been shown to improve clinical outcomes. Other modifications to the 2011 guideline update are elucidated in Table 2.
More Research Warranted
The AHA panel acknowledged that physician and patient barriers to adhering to lifestyle and medical recommendations may limit adherence to the guidelines. New sections were added on guideline implementation to address this issue. “We have also issued a call to action that the medical and scientific communities begin to study and discuss gender-specific data on adverse effects and efficacy of preventive interventions,” says Dr. Mosca. “The hope is that we’ll be able to make more appropriate recommendations based on the net balance of benefit and risk, which may differ according to gender. This information is critical to inform future guidelines.”
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