Preventing Cardiovascular Disease in Women by
Caryn Preston
Outline of Chapter
A. Definition of
Cardiovascular Disease (CVD)
CVD is an umbrella term that covers diseases of the heart and the blood vessel system within the body, usually related to atherosclerosis (narrowing of the arterial blood vessel wall caused by the formation of fatty plaques). In coronary heart disease (CHD) narrowing of the arteries supplying the heart can cause cardiac ischemia resulting in angina symptoms (chest discomfort and radiating pain). If the artery becomes blocked it can result in myocardial infarction (death of a part of the heart muscle). A cerebrovascular accident (Stroke) occurs if a cerebral artery becomes occluded or ruptures leading to tissue death. Similar narrowings or occlusions can occur in peripheral vessels affecting the limbs resulting in impaired circulation (peripheral vascular disease-PVD). Hypertension, congestive heart failure, arterial aneurysms, cardiomegaly, arrhythmias, cardiac arrest, cardiomyopathy, rheumatic heart disease and valvular disorders are also included in CVD (1, 2).
B. Extent of the
Problem
According to the World Health Organization about 17 million people globally die of CVD each year. By 2010 it is estimated that CVD will overtake other causes of death in developing countries and become the leading cause of death. Up to 7.2 million deaths are due to CHD, 5.5 million due to stroke and 3.9 million due to hypertension and other heart conditions. 20 million people survive heart attacks and strokes resulting in high medical costs and loss of income affecting families and nations. As dietary patterns, activity levels and tobacco use change in developing countries these risk factors will increase. 80% of CVD may be preventable by implementing lifestyle changes. These changes could also decrease the risk of type 2 diabetes, chronic respiratory disorders and some cancers (2).
CVD is the number one killer of women in the
Cardiovascular deaths in men are declining but in women it remains the same or is increasing. Women under the age of 65 years are more than twice as likely as men to die from myocardial infarction. 38% of those who survive die in the first year compared to 25% in men. Within 6 years 35% of women have a recurrent infarction compared to 18% of men. CHD alone accounts for 250 000 deaths in women and CHD affects more women in racial minorities (7, 3).
The problem of CVD may be complicated by various misconceptions. A gap exists in the perceived and actual risk of CVD in minority and younger women. In a study conducted by the American Heart Association (AHA) in 1997 only 7% of women thought CVD was their greatest health risk and a third thought it was the leading cause of death. A follow up survey was done in 2003. This time almost half of the women identified CVD as the leading cause of death and 13% thought CVD was their leading health problem. Most women identified the media and the internet as sources of information about heart disease. Only 38% had discussed heart disease with their doctors. Even though awareness about CVD as the leading cause of death has significantly increased only a small percentage of women believe themselves to be at risk. Hispanic women and younger women feel uninformed about the disease. This may suggest the need to target these groups of women and increase opportunities for patient–physician discussions (8). There is also a perception that women are protected from heart disease. While this may be true in premenopausal women post menopausal women are at greater risk and especially vulnerable if risk factors are not treated (9). It is therefore important to increase awareness among healthy asymptomatic people of their risk for CVD.
C. Risk Factors
and Prevention
The first guidelines for women for preventive cardiology came out in 1999. Nearly two thirds of women who die from CHD have had no previous symptoms. It is therefore fundamentally important to address risk factors in the absence of clinical symptoms. The distinction between primary and secondary prevention has become less clear due to technological advances allowing for earlier detection of CVD. The idea of CVD as a continuum of risk is favored over the more traditional categorical definition of CVD i.e. patients do have or don’t have the disease. Risk groups are defined by their probability of having a coronary event within 10 years. This is based on the Framingham Risk Score for women. Risk intervention can then be matched to this baseline CVD risk. High risk is considered >20% (established CVD or other chronic diseases), intermediate risk 10%-20% (subclinical CVD, multiple risk factors, family history), lower risk <10% (multiple risk factors, metabolic syndrome), optimal <10% (good management of risk factors) (10).
Coronary heart disease only becomes clinically evident in women a decade later than in men. For this reason some women believe prevention can be delayed until they are in their 50’s. Studies show that this is a dangerous perception as signs of atherosclerosis may be found in women in their 20s. Cardiovascular risk factors are associated with this development and prevention should really start in childhood (8,16).
There are various risk factors that play a role in CVD. Some of these are non modifiable such as age, sex, family history and race. Women with a family history of a first degree female relative having a cardiac event before 65 years and/or a male relative before 55 years are at increased risk for CVD. Black women are more likely than white to have increased risk (6).
Other risk factors are modifiable and these include smoking, obesity, physical inactivity, hypertension, dyslipidemia, socioeconomic status, alcohol consumption, diet, depression and stress.
Modifiable Risk factors and interventions
|
Risk factors |
Recommendations (10, 11). |
|
Smoking |
No smoking and avoid environmental tobacco smoke |
|
Diet |
Include fruits, vegetables, whole grains, low fat dairy, fish, legumes, saturated fats <10% total calories, cholesterol <300mg/d, avoid trans fats, use salt and sugar sparingly |
|
Physical activity |
Moderate physical activity (30 minutes) on most days of the week or 10 000 steps/day(pedometer) |
|
Weight |
Waist circumference < 35 inches and BMI 18.5 -24.9kg/m² |
|
Blood pressure |
<120/80mmHg |
|
LDL-C HDL-C Triglycerides |
<100mg/dL >50mg/dL <150mg/dL |
|
Alcohol |
<1-2 glasses of alcohol per day |
|
Diabetes |
HbA1C <7% |
Emphasis is being placed on identifying those without clinical evidence but with a high risk of developing cardiovascular disease. There needs to be increased awareness among healthy people of their risk and enhanced knowledge of risk factor parameters. A good proportion of people are unaware of values for their blood pressure, total cholesterol and blood glucose. Those who have abnormal values for these measures may also have poor treatment compliance (12).
Management of risk factors is cost effective and can be very effective in largely preventing CHD. Smoking rates are declining but less so for women than men (13). Smoking increases the risk of a heart attack up to 6 times in heavy smokers. This risk can drop to 50% after smoking cessation within the first year. By the fifth year of cessation the risk is almost the same as for a nonsmoker. Passive smoking also increases the risk of CVD (6).
Obesity is on the rise and almost 25% of women report no regular physical activity (13). Obesity and physical inactivity independent of each other can increase the risk of CHD. Therefore maintenance of a healthy weight and regular activity are key to preventing CHD. (14) Physical activity does not need to be structured exercise and can involve walking during breaks, taking the stairs more often and using a pedometer with the goal of 10 000 steps per day. If overweight or obese, a loss of 5 to 10 % of body weight can beneficially affect cholesterol, blood pressure blood sugar. Decreasing food by 500 calories per day and 30 minutes of moderate activity can result in weight loss of 1-2 pounds per week (6).
Regular stress at home or work can increase risk by as much as 75%. To combat this, women need to get enough sleep, exercise, manage stress and eat healthily. Depression has also been linked to increased risk of CVD and women may need professional help in this situation (6). Women with high marital stress also are less likely to remain free from recurrent cardiac events than women with low marital stress (20).
Women with diabetes are 3 to 7 times more likely to develop CVD. Exercise, diet and medication are very important in controlling diabetes and consequently decreasing CVD risk (6). A clustering of risk factors can occur in diabetic women. This increased risk can be explained by CVD risk factors associated with insulin resistance (obesity, hypertension and dyslipidemia) (15). Differences in treatment by gender may result in increased risk in women with diabetes. Treating CHD risk factors help to decrease mortality in diabetics. Women are less likely to receive treatment for CHD risk factors and more likely to have poor control of these factors when compared to men. Treatment of CHD risk factors therefore needs to be aggressive in women with diabetes (11).
Almost half of women over the age of 45 have hypertension and about 40% have hyperlipidemia. Low levels of HDL may be a stronger risk factor for women over the age of 65 than men in the same age group. Recognizing these high risk individuals is important so that they can be targeted for aggressive risk factor management even if they have not had an event. First time cardiovascular events are often fatal in women so the emphasis should be placed on management of risk factors before clinical presentation (13).
Medications
Antihypertensive medications are recommended for those who have persistent blood pressure greater than 140/90mmHg or 130/80mmHg in diabetics. These may take the form of diuretics, beta-blockers or angiotensin-converting enzyme inhibitors. Cholesterol lowering medications that may be used are statins, niacin or fibrates. Many Aspirin studies have been conducted in men so potential benefits in women must be weighed against risks of bleeds and ulcers. Postmenopausal hormone replacement therapy (HRT) is not recommended for women to prevent CVD as recent studies have shown an increased risk of CVD in women on HRT. However this risk must be balanced with the benefits of HRT in women with a high risk of developing osteoporosis (6).
Diagnostic Tests
Most recommendations for non-invasive testing are based on results from studies on middle-aged men. Women who have symptoms and are at high risk should have testing including exercise stress testing with imaging, exercise electrocardiology or pharmacological stress testing for those unable to exercise. Other tests include computed tomography to identify calcium in the coronary arteries and provide a calcium score for risk quantification. Cardiovascular magnetic imaging can identify blood flow and heart function. This may be recommended in the future for women but not presently. Carotid ultrasound may be used to identify thickness of the intima and media of the carotid artery. There is insufficient evidence at present to recommend this in women (6).
Blood levels of C-reactive protein, homocysteine, lipoprotein(a) and fibrinogen may also be indicators of CVD. In the future these may help improve risk prediction and stratification (6).
Surgery and Rehabilitation
Percutaneous coronary interventions (stent, angioplasty) and coronary artery bypass surgery are used to treat blocked arteries to the heart. Cardiac rehabilitation is recommended after such procedures or for women who have had myocardial infarctions and unstable angina. However women are less likely to be referred for rehabilitation than men. They also may also have increased barriers to cardiac rehabilitation because they are often older when such events occur (6).
Education
Education of women during office visits is essential to
identify risk factors and to implement earlier and more aggressive control of
these risk factors. Need to change women’s perceptions. Risk factors predict
sudden cardiac death and therefore should be addressed to prevent outcome (7).
Some studies suggest optimal times to discuss risk factors
and implement intervention. During pregnancy,smoking cessation and weight gain
can be addressed. In post menopausal women this could be the time to discuss
HRT risks/ benefits (13).
Although social marketing increases awareness and self
efficacy, this effect is not maintained. Researchers suggest medical
professionals need to reinforce this information at point of care (18).
Sometimes it may be the healthcare professionals that are unaware of the risk in women for heart disease. In 2004 the AHA distributed treatment guidelines to 80 000 physicians through the Go Red for Women campaign to try to address this issue (17).
D. Public Policy
Policies enacted by the government can help to decrease risk
in the population. According to the WHO the most
cost effective way of reducing risk is to address populations. These are some
examples of current policies in the
Healthy People 2010
This agenda comes from the federal government. The goals of the 16 objectives that address CVD are to detect and decrease risk factors for cardiovascular disease, to recognize and treat heart attacks and strokes early and to prevent occurrences of these events.
Some examples of goals:
http://www.cdc.gov/cvh/hp2010/objectives.htm#summary
Steps to a Healthier US
This program is focused on reducing diabetes, obesity and
asthma by targeting three risk factors: physical activity, nutrition and
tobacco use.
The Community AED Act of 2001 (S. 1275)
This act authorized $55 million for communities to purchase AEDs (automated external defibrillators) for public places and train first responders.
http://www.redcross.org/services/hss/courses/aed.html
E. Programs
Here are a few examples of recognized successful programs that help to reduce CVD by addressing lifestyle interventions.
DASH eating plan (Dietary Approaches to Stop Hypertension)
This dietary plan is clinically proven to decrease hypertension. It includes menus and advice about reading food labels, forms to help track food habits, to plan for meals and shopping tips.
http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/
The Wise Woman program
This program is funded by the CDC to improve the health of uninsured women by increasing access to screening and lifestyle interventions. In 1999, 1 in 10 women between the ages of 40 and 65 were uninsured. These women are mostly likely to be minority groups, less educated and poorer. They tend to smoke, be overweight and are less physically active. They are also less likely to be screened for hypertension, cholesterol, advised to quit smoking and lose weight. This combination of characteristics puts them at increased risk for CVD. The program now consists of 15 projects in 14 states. Between 2000 and 2004 over 30 000 women enrolled. Services include screening for hypertension, cholesterol and blood sugar levels. Participants are enrolled in sponsored exercise classes, walking groups or provided with scholarships to local gyms. Counseling, health education and referrals are also part of the program.
National Weight Loss Control Registry
This registry keeps track of over 5 000 people who have maintained a weight loss of >30 pounds for >1 year. Some measures of success were found to be low fat diet, self monitoring and physical activity.
Codman award winner
The diabetic program at
http://www.jointcommission.org/Codman/05_memorial_hc.htm
International Programs
The government in
A study to test the efficacy of the Women’s Wellness Program
in
Other Programs
that address CVD
The National Committee for Quality Assurance and the AHA offer a program to recognize physicians who deliver quality care to patients with CVD by providing screenings and helping patients to control risk factors. The hope is that recognition of physicians will result in improved care for patients (3).
http://www.ncqa.org/Communications/News/hsrpannouncement.htmOKE CARE
Search Your Heart is a community based program in a church setting targeted at African Americans designed after successful affiliated programs (3).
http://www.americanheart.org/presenter.jhtml?identifier=4533
Get With The
Guidelines is a
quality improvement program to ensure that patients are treated according to
the most recent evidence-based guidelines. These guidelines are aimed at coronary
artery disease, stroke and heart failure (3).
Go Red For Women is aimed at raising awareness of women’s
risk of heart disease. Over 290,000 women have registered for this campaign. Tools and resources are also offered for
healthcare providers (3).
Choose To Move is a
free 12 week physical activity program for women focused on exercising
regularly, eating healthfully and learning to develop beneficial habits (3).
Just Move is sponsored by the American Heart Association. It is an interactive website that contains an exercise diary, advice on how to start exercising, information on calories, cholesterol and other articles. Events like Heart Walk are listed (one million walkers participating in 600 events raising funds and exercising). People can create their own websites to increase sponsorship for such events (3).
Off (officially free from) Nicotine is a tobacco cessation program that can be used by healthcare providers in primary health care settings. It includes four weekly sessions and Exhaled Carbon Monoxide (Ex CO) monitors are also used to provide measurements and to track participants’ progress.
Moving into Action- action items based on national guidelines and other evidence to help governors, state legislators, local officials, employers and health professionals promote healthy behaviors to reduce risk of CVD.
http://www.cdc.gov/cvh/library/moving_into_action/index.htm
The
F. Further
resources
This USDA site allows one to access My Pyramid food guide according to sex, age and physical activity. Information about food assistance programs, advice on shopping, meal planning and cooking healthy meals is provided. A BMI calculator is also available.
http://www.cdc.gov/nccdphp/dnpa/physical/measuring/index.htm
This CDC website provides advice on how to get started with physical activity and has a number of measurement tools.
The Department of Health and Human Services provides tools through their website to measure fitness and logs to keep track of fitness.
www.deliciousdecisions.org
Recipes for people with heart problems produced by the American Heart Association.
www.strokeassociation.org
This division
of the American Heart Association
focuses on reducing disability and death from stroke through research,
education, fund raising and advocacy..
http://surgeongeneral.gov/tobacco/treating_tobacco_use.pdf
Treating tobacco dependence.
http://www.nhlbi.nih.gov/about/framingham/riskabs.htm
A tool for people to calculate their risk of developing a cardiac event in 10 years.
This site has interactive maps that show state and county rates for heart disease and stroke by year, gender and race.
http://www.ahrq.gov/clinic/uspstfix.htm
The US Preventive Services Task Force website has current evidence-based guidelines for screening.
http://www.case.edu/med/epidbio/mphp439/
Related chapters in the Public Health Management and Policy online textbook: Diabetes, Hypertension, Stroke and Current Issues in Women’s Health
G. Textbooks and
Journals
The ESC Textbook of Cardiovascular Medicine edited by
John Camm, Thomas F. Luscher and Patrick W. Serruys. Blackwell Publishing 2006.
Available through Amazon, this cardiovascular textbook is published in
partnership with an international society and is considered to be the benchmark
for cardiologists in
Cardiovascular Physiology Concepts is an online resource for cardiovascular physiology concepts by Richard E. Klabunde, PhD
Journals
on cardiovascular diseases published by American
Heart Association. Abstracts and sample issue available online.
Current evidence-based guidelines for physicians for the prevention of cardiovascular disease.
http://www.invisionguide.com/heart/flash/index_reg.php
Online interactive heart guide for the general public
H. Footnotes