With enthusiasm and a shared sense of purpose, experts in women and heart disease gathered in Ottawa this April for the first Canadian Women’s Heart Health Summit. Attendees included leading figures in clinical care and research from across North America. The event aimed to lay the groundwork for putting the issue of women and heart disease prominently in the sights of the Canadian public, health care professionals and policymakers.
Heart disease is the number one killer of women worldwide, ending the lives of more women than all cancers combined. Yet, heart disease is still often considered primarily a male concern, while for women, breast cancer is regularly misidentified as the major health issue.
Research by the Ottawa Heart Institute’s Canadian Women’s Heart Health Centre, primary organizer of the Summit in partnership with the Heart and Stroke Foundation of Canada, has shown that Canadian women themselves are not well aware of the symptoms and risk factors of heart disease.
As keynote speaker Sharonne Hayes, MD, of the Mayo Clinic indicated, heart health should be central to women’s health. She kicked off the proceedings by emphasizing that heart disease in women is a “huge public health issue” with “huge health disparities” for women as compared to men and a “huge awareness problem among women and health care providers.”
In light of this broad lack of awareness, speakers throughout the Summit program laid out the many ways heart disease and cardiac care are different or unique for women (see the infographic “What We Know about Women and Heart Disease” for an overview). Importantly, these differences impact the diagnosis, care and treatment outcomes for women—mostly for the worse.
Risk Factors and Symptoms
Physiological differences between men and women are at the core of how heart disease affects them differently. From the perspective of risk, hormonal changes have a great affect on women, generally providing protection early in life which then disappears with menopause. Factors associated with pregnancy are also closely tied to heart disease (see the sidebar “Pregnancy and Heart Disease”). Pregnancy can act as a stress test that identifies women with underlying risk, but it can also cause conditions that increase the risk of heart disease for the rest of a woman’s life.
Psychosocial factors are also essential to understanding risk in women. Socio-economic disadvantage increases risk and is more likely to affect women across all ethnicities and age groups. The feminine gender role (socially determined), as opposed to sex (physiologically determined), is associated with greater risk of heart attack.
While many of the lifestyle factors that put men at risk for heart disease are the same for women, several have a greater impact in women—smoking and diabetes in particular. Additionally, health care providers are less likely to discuss prevention and heart health with women.
Symptoms of heart attack in women can be both the same and different as those for men. While women are less likely to experience classic chest pain, the majority of them still do. Other women experience milder and more diffuse symptoms that are not as easily recognized, including weakness, shortness of breath, tiredness and nausea. Such symptoms are often discounted or ignored both by women and health care providers.
Both the circumstances and the nature of heart disease that women suffer from can differ significantly from men. Women tend to get heart disease and have heart attacks later in life. Due in part to the usual emergence of heart disease later in life, female heart patients are more likely also to suffer from other health conditions (co-morbidities) which can make their care more complex.
With coronary artery disease, women often develop diffuse atherosclerosis found throughout their arteries rather than the large plaque build-up that causes major blockages in men. Women are twice as likely to develop heart failure after a heart attack, but treatment of the type most common in women (heart failure with preserved ejection fraction (HFpEF)) is not nearly as well understood. Several other cardiovascular conditions are also more common in women, including stroke, heart valve disease and spontaneous coronary artery dissection.
Women’s symptoms are often misread and diagnostic tests misinterpreted due to knowledge gaps and unconscious bias among health care providers. The result is that women are often misdiagnosed and appropriate treatment is delayed. For example, younger women and women not experiencing chest pain and are less likely to be correctly diagnosed with heart attack. Across all socioeconomic levels and age groups, women are less likely to undergo an angiogram following a heart attack.
Some standard tests are less accurate for women or require different interpretation. Exercise stress tests often produce inconclusive results in women, while angiograms often appear normal in women following a heart attack. Troponin, a biomarker for heart attack, is present at lower levels in women than in men, potentially causing this indicator to appear normal.
Treatment and Outcomes
Delays in treatment, knowledge gaps and access to care can negatively impact outcomes for women. In addition, differences in male and female physiology and psychosocial factors impact the effectiveness of certain treatments. The fact that relevant research has historically been conducted mostly only in men makes the situation worse.
In response to heart attack and heart failure, the shape, size and function of the heart can change in both sexes. The result of this process, called remodelling, is different in men and women. Women have a greater risk of procedure-related bleeding events, and outcomes differ for women for a variety of treatments including, bypass surgery, angioplasty, anti-clotting therapy, mitral valve surgery, catheter-based aortic valve replacement (TAVI) and peripheral arterial surgery.
Heart attack outcomes are generally worse for women. They are more likely to die in hospital following a heart attack and are less likely to return to work. Younger women who have a heart attack are more likely to die.
Atrial fibrillation is more likely to result in stroke, heart attack, heart failure and death in women, and women are more likely to suffer cardiac damage (cardiotoxicity) from certain cancer drugs. Aspirin reduces the risk of heart attack in men but reduces the risk of stroke in women.
In terms of recovery, cardiac rehabilitation has a greater impact on survival in women than in men, but women are less likely to be referred to rehab and are less likely to take advantage of rehab programs. Women are also less likely to adhere to their medication, as prescribed.
Clearly, the experience of heart disease differs between the sexes in myriad ways. As Karin Humphries, DSc, University of British Columbia, and other speakers made clear, it is time to move beyond simply identifying these differences and start doing the research needed to understand them so that we can improve outcomes for women.
Pregnancy and Heart Disease
The stresses and physiological changes of pregnancy can provide early identification of women at risk for a later cardiac event.
Pregnancy-related risk factors and conditions include:
- Plancental disorders, such as preeclampsia, in which the placenta does not implant properly. These conditions affect 7% of pregnant women and increase the risk for a variety of cardiac conditions, including arrhythmia, heart failure and chronic hypertension. Preeclampsia early in pregnancy increases the risk of early death.
- Gestational diabetes increases the risk of cardiovascular disease and nearly a fifth of women who experience gestational diabetes develop type 2 diabetes.
- Pregnancy-related hypertension strongly increases the risk of chronic hypertension.
- Peripartum cardiomyopathy reduces the pumping capacity of the heart. The condition has a 4% mortality rate at one year and 16% at seven years.
Making healthy lifestyle changes after pregnancy can mitigate increased risk for heart disease, but women tend not to follow up on these conditions at postpartum clinics. Data is lacking on how best to guide care postpartum. Canadian guidelines will be changing to address pregnancy-related risk for heart disease.
- Part Two of our Summit coverage on the knowledge gaps and future directions: What’s Needed to Improve Women’s Heart Health?
- Canadian Women’s Heart Health Summit Set to Drive National Action