Tarheel Health Portal/Heart Disease

Heart Disease is the number 1 killer of women, killing more women than all cancers combined with 1 in every 4 women’s death being caused by heart disease. Generally referring to conditions that involve narrowed or blocked blood vessels that can lead to a heart attack, chest pain (angina) or stroke, heart disease can be an umbrella term for other heart conditions, such as those that affect your heart's muscle, valves or rhythm. Because most research has been done on men, it has been considered a “mans’ disease”, but this is simply not true. The fact is that signs and symptoms differ between men and women, leading women to be missed diagnosed or diagnosed too late. With breast cancer having so much media coverage, most women think that it is their main worry even though 12 times as many woman die from heart disease than breast cancer yearly ; only 54 % of women know that Heart Disease is their number 1 killer. Heart disease not only affects those with it, with one out of two American women developing heart and vascular disease, but their friends and family well. With so many women dying from a condition that can be avoided, more media coverage and research is need so that women know what they can do to become aware and lower their risk factors for heart disease.

Cross section of plaque filled artery

Risk Factors

As for-mentioned, heart disease is caused by the narrowing and/or blockage of ones’ blood vessels leading to and from the heart. Because “two out of three American women have at least one risk factor for heart disease, and high blood pressure, high LDL cholesterol, and smoking are all major causes of heart disease, it is important that a women exercises regularly, consumes less alcohol, and maintains a healthy diet. A big problem is the difference that the sex of the afflicted has on their symptoms and presentation of risk factors. For example, women with diabetes have a 2.6 times greater risk of dying from coronary heart disease than women without diabetes as compared to only a 1.8 times increased risk between men with and without diabetes. Another difference between men and women is in presentation of their symptoms. Women tend to show symptoms such as such as back, jaw, and neck pain, burning in the chest, abdominal discomfort, nausea, fatigue or no signs at all. Men on the other hand show signs such as pain in the left arm and chest, cold sweats, and nausea. With such drastic differences, women either ignore or down play their symptoms as something less serious such as the flu. The onset of heart disease symptoms also varies greatly among men and women. Women, at the first sign of symptoms, tend to be 10 years older than men, and at the time of their first heart attack, they are usually 20 years older. Because of late presentation of symptoms, women often need urgent intervention, but with smaller coronary vessels than men, surgery is more difficult. Moreover, because women are more likely to have comorbid factors such as diabetes mellitus, hypertension, and heart failure, the mortality rate for women is notably higher with “455,000 American women dying of heart disease every year, compared to 410,000 men” . Fortunately, there are steps that women can take to greatly reduce their chance of developing heart disease. Though growing, the awareness and education for physicians and the public is still severely lacking.

Type of Fat Intake

Based on the 20 year Nurses’ Health Study from 1980-2000, factors for heart disease were tested including: dietary fat intake; low –carbohydrate diet score; and obesity and physical activity. During the examination of type and amount of fat intake, 1,766 of the 78,778 cardiovascular and diabetes free women (ages 30-55) developed Coronary Heart Disease. Of these 1,766 cases, 1,241 were non-fatal heart attacks but 525 lead to Coronary Heart Disease related deaths. It was found that trans-fat was strongly associated with CHD in women younger than 65 while a polyunsaturated fat intake and risk of CHD was more strongly associated with women over 65. Trans-fat can contribute to increased risk of CHD by influencing blood lipids, including: concentrations of low density lipoprotein cholesterol and particle size, high density lipoprotein cholesterol, and triglycerides. With this information, I think that the avoidance of processed food or foods high in trans-fat would be advised. The problem is that because this study was completed over 15 years ago, the process by which most food is made has changed. Nowadays, the use of chemicals and artificially processed food has exponentially increased, leading to a greater production of trans-fats.

Low- Carbohydrate Diet Score

Within the Nurses’ Health Study, the effect that ones’ low carbohydrate diet score has on their risk of CHD was examined.  The score was based on the percentage of energy intake as carbohydrates, proteins, and fats. If one had a higher score, it represented a higher intake of fat and proteins with a lower intake of carbohydrates. Because most carbohydrate restricting diets encourage the consumption of animal products, which contain higher amounts of fat and cholesterol, the consumption of these products can cause a raise in serum lipid levels, leading to an increased risk of CHD. With this in mind, a second score was taken using vegetable fat and cholesterol in lure of the animal based products. Of the 82,802 women selected to study (all of which had no previous history of diabetes, cancer or cardiovascular disease), there were 1994 new cases of CHD after the 20 year follow up.  In the end, though a lower diet score (using animal products) was not associated with CHD risk, when vegetable protein and cholesterol was used, a lower diet score was associated with a moderately lower risk of CHD. However, this study does not take into account that not everyone follows a low-carb diet and that many people go on low fat, low carb, high protein diets. With this confounding variable, the results may be different. It should also be noted that types of fat, such as discussed in Willet’s article, have varying levels of  impact on risk of CHD with polyunsaturated and monounsaturated fats having a decreased risk effect.

Obesity and Physical Activity

Types and amounts of fat can also corresponds with obesity levels. Dr. Hu of Harvard University School of Public Health used the Nurses’ Health Study to evaluate the correspondence of obesity and physical activity levels with the risk of CHD. Because obesity is caused by excessive intake of fat with little to no exercise, I believe that this is one of the easiest ways to prevent heart disease. After following 88,393 cardiovascular disease and cancer free women, 2,358 incidents of CHD related problems were documented. Of these 2,358 incidents, there were 1,469 cases of nonfatal heart conditions and 889 were conditions leading to fatalities. Both obesity and physical activity levels were found to be independently linked to risk of CHD; those with high levels of obesity had were at a greater risk of CHD while those with high levels of physical activity had a reduced risk of CHD.  However, “even a modest weight gain (4 to 10kg) during adulthood was associated with 27% increased risk of CHD”. Because body weight and lack of physical activity both independently effect the development of CHD, women must maintain a healthy diet combined with frequent exercise.          

Being Informed

Recognition is not only a problem for women and their loved ones, but also doctors. With research mainly being done on men, it is not uncommon for a doctor to misdiagnose a women with heart disease as something else. “An experimental case study design tested physician accuracy and determinants of Cardiovascular Disease risk level assignment and application of guidelines among high-, intermediate-, or low-risk patients” . Among the 500 randomly selected physicians, 300 were primary care physicians, 100 were OB/GYNs, and 100 were cardiologists. After rating themselves low in their ability to help patients prevent CVD, only 1 out of 5 doctors realized that more women died yearly form CVD than men. This fact is astonishing considering 1 out of 5 physicians in this study were cardiologists, someone who specializes in the study of the heart. Because many physicians are ignorant to the differing symptoms of a heart attack between men and women, a women’s claims tend to accepted with less urgency. On average, it takes about 15 minutes after the initial examination for a physician to order an electrocardiogram (ECG) for men while it takes an astounding 21 minutes for an ECG to be ordered for a women .

With women usually displaying atypical symptoms of a heart attack, such as jaw pain, upper back pain, a feeling of indigestion, nausea, and fatigue, their symptoms are initially dismissed as anxiety or another health problems . When women did display the “classic” heart attack symptoms, huge disparities of treatment between the sexes appeared. “Only 15 percent of the doctors diagnosed heart disease in the woman, compared to 56 percent for the man, and only 30 percent referred the woman to a cardiologist, compared to 62 percent for the men. Finally, only 13 percent suggested cardiac medication for the woman, compared to 47 percent for the men…” with the presence of stress “…women’s physical symptoms were reinterpreted as psychological, while men's symptoms were perceived as organic whether or not stressors were present.” In a study conducted by Shulman et al., in regards to how a physician managed a patients’ chest pain, it was independently based on the gender of a patient. Based on this information, it is suggested that improving physician assessment of CHD risk may be important for helping to reduce sex-based disparities in care. 

Community

You may read this and think that it does not concern you, but on the contrary. With heart disease affecting so many women, some unknowingly, there is a very strong possibility that someone you know and love is suffering. Be it your mom, sister, aunt, grandma, or neighbor, at least 1 will have/develop this disease while even more will have risk factors. Here at UNC, we have a whole hospital dedicated to heart disease and women’s health. Along with UNC, Duke Hospitals are paving the way in research. But the most notable efforts, in my opinion, are the efforts of Cedar- Sinai’s Barbra Streisand Women’s Heart Center and the American Heart Association’s Go Red for Women. These two organizations are bringing the attention of this disease to the forefront by way of campaigns and media. Through their efforts and combined, growing knowledge from the research being done at many centers such as UNC and Duke, Heart Disease in Women and overall heart health of women is finally gaining momentum and attention.

Further Reading

UNC Health Care

Barbra Streisands Women's Heart Center

Duke Heart Care

Womesn's Cardiovascular Health

American Heart Association