Preventing Cardiovascular Disease in Women
Nieca Goldberg Medical Director, New York University Women’s Heart Program, New York University School of Medicine
Cardiovascular disease (CVD) is the leading cause of death and disability in
American women. Since 1984, more women have died of cardiovascular
disease than men. More than 200,000 of these deaths are due to coronary
heart disease.1 In two-thirds of these women, sudden death was the
presenting symptom and studies2 show that 90% of them had at least one
of the modifiable risk factors (e.g. hypertension, smoking, or diabetes). Not
only is there a gender disparity in CVD deaths, there are also racial disparities.
CVD death rates are higher in African-American women compared with
white women. There is also a greater prevalence of hypertension, obesity,
and diabetes in African-American and Hispanic women.
Over the last 10 years there has been an increase in public awareness of
cardiovascular disease in women, yet there still remains a gap between a
woman’s awareness of cardiovascular disease and her actual risk. In the
2006 American Heart Association survey,3 57% of the women surveyed
were aware of heart disease as the leading cause of death in women,
compared with 30% in 1997. There is still little evidence that women
personalize this awareness, as only 21% of women identify heart disease or
heart attack as a woman’s greatest health problem. Unfortunately, there is
a disparity in awareness among African-American and Hispanic women.
Only 15% of African-American women and 6% of Hispanic women believe
that they are at risk for CVD. This disparity needs to be improved, as these
women have a high prevalence of risk factors such as diabetes, obesity,
sedentary lifestyle, and hypertension.
With increased awareness comes confusion. Women felt that the media
contributed to the confusion about diet, hormone therapy, and the use of
aspirin and antioxidant vitamin supplements to reduce risk for heart disease.
Women between the ages of 25 and 45 years were more likely to find the
information confusing compared with women between the ages of 45 and
65 years. This is an important gap to narrow, as the CVD risk starts early.
Autopsy studies in young women showed the development of
atherosclerosis related to risks such as smoking and obesity.4 There is also a
lack of awareness that women’s symptoms can be atypical for heart attack.
Lack of recognition of these symptoms could delay emergency treatment for
acute coronary syndrome. All of these factors contribute to women’s
excessive death due to and risk of CVD. The burden of preventing CVD
should not rest solely on women. The women in the 2006 survey responded
that their physicians discussed women at risk; it is also the responsibility of
healthcare providers. Less than half of the women recalled their physician
discussing preventive strategies for heart disease with them. In a study of
lipid-lowering therapy in high-risk women in a managed care setting, it was
found that only 33% received the recommended lipid-lowering therapy
based on National Cholesterol Education Panel (NECP) guidelines.5 Physicians
have identified lack of insurance reimbursement as a barrier to counseling
patients on lifestyle interventions to prevent cardiovascular disease.6
The recent evidence-based guidelines in women7 differed from previous
guidelines in recommending that CVD screening for women begin at age
20, and use the Framingham Risk Score (FRS)8 for the prescription of lipid
therapy. The change was based on limitations of the FRS for women. The
FRS overestimates and underestimates CVD risk in non-white women,
focuses on short-term absolute risk, and omits family history, a factor
that increases a woman’s risk for CVD 2.3-fold. Women can be at low
risk according to FRS for CVD yet have subclinical CVD such as coronary
artery calcification.9
Instead, new guidelines7 classify women as high-risk, at-risk, or optimal-risk.
High-risk women are those with established coronary heart disease,
cerebrovascular disease, and peripheral vascular disease. It also includes
women who are diabetic or have end-stage chronic kidney disease or aortic
aneurysms. At-risk women have one or more of the already established
modifiable risk factors such as smoking, family history, hypertension, and
dyslipidemia; subclinical CVD such as coronary artery calcification; metabolic
syndrome; and poor exercise tolerance on treadmill testing. Optimal-risk
women are those women with a healthy lifestyle without risk factors. Shaw
et al.10 identified gender-related variability in prevalence and outcome in
cardiovascular risk factors. Men and women share cardiovascular risk
factors; although there are more male smokers and more hypertensive men,
there is an excess of young female smokers and elderly hypertensive
women. Men have higher low-density lipoprotein (LDL) cholesterol levels
until their fifties compared with women, until women reach menopause,
when their LDL cholesterol levels rise. Women have higher high-density
lipoprotein (HDL) cholesterol levels compared with men throughout their
life, though at menopause women do have a slight decline in HDL
cholesterol. HDL is a greater predictor of fatal ischemic heart disease in
women compared with in men. Hypertriglyceridemia is a more potent risk
factor for ischemic heart disease in women compared with in men, at 76
and 32%, respectively.11
Metabolic syndrome is a greater predictor of subclinical atherosclerotic
disease than obesity alone. The Wise investigators showed that women
with metabolic syndrome had a four-fold increase in CVD risk compared
with those women with a normal metabolic status.12 Diabetic women have
a two-fold increase in CVD risk compared with non-diabetic women.10
Novel risk markers such as highly sensitive C-reactive protein (hsCRP) may
have a role in helping further stratify women at intermediate cardiovascular risk. Ridker and colleagues have shown that elevated CRP
increases CVD in women who have normal cholesterol.13 Recently, the
Reynolds score14 has been validated in women aged 45 and older, and
hsCRP was added to CVD risk factors such as smoking, diabetes, and
parental history of CVD, total cholesterol, and HDL cholesterol. The
Reynolds Risk Score reclassified 40–50% of the women who were at
intermediate risk in the FRS to higher or lower risk categories. One of the
limitations of the Reynolds score is that it has been predominantly
validated in Caucasian women at midlife. Therefore, we do not yet know
if it is valid in other populations of women.
