Heart disease is the number one cause of death in women. More women die secondary to heart disease than all forms of cancer combined. One out of every three women will develop heart disease and half of a million women will die from it annually. In comparison, forty thousand women die of breast cancer yearly. Fifty percent of women die during their first heart attack, whereas only thirty percent of men die. Women are also more likely to have another heart attack within a year. Heart disease is much more common in men in their fifties, but women catch up to men by their sixties. One theory is that a woman’s natural hormones protect her from heart disease, which she no longer produces after fifty. Numerous observational studies have shown that both estrogens and progesterone are protective to the cardiovascular system. After a women reaches menopause she no longer produces these hormones. She is often given synthetic hormones, which are possibly harmful to the heart. See the chapter on hormones and research on hormone replacement therapy. Women can continue to have protection from heart disease if they take bio-identical hormones. Bio-identical hormones are identical to the protective hormones a woman produced until menopause.
Women’s bodies are much different from men’s bodies and heart disease behaves differently between the sexes. Women have smaller hearts and smaller blood vessels. Men usually develop heart attacks when an atherosclerotic plaque in the coronary aterery dislodges and blocks the blood vessel downstream. Heart attacks also result from enlargement of the plaque to the point where it occludes the entire vessel. Oxygen can no longer reach this part of the heart causing pain (angina), irregular heartbeats (arrhythmia), or heart failure. Artherosclerosis is when fatty deposits, cholesterol, and calcium collect on the lining of artery walls, forming a plaque. The most common form of heart attacks in women is secondary to artherosclerosis as well. But women are more prone to developing artherosclerosis in a more diffuse manner. Instead of the plaque gathering in one part of the vessel, artherosclerosis is spread more evenly throughout the vessel. Additionally women who suffer from heart attacks often do not have artherosclerosis. It is felt that women may instead suffer from vasospasm of the major heart vessels. When an artery has spasms, especially in a smaller female blood vessel, it cuts off the ability of blood to pass through the artery. Studies have shown that women with smaller coronary arteries suffer more from heart disease than women with larger blood vessels. The size of arteries in men did not show the same findings. Secondary to different etiologies of heart attacks between men and women, there symptoms are often much different. Men will often have the classic symptoms of a heart attack; pain in the chest radiating to the left arm or jaw associated with shortness of breath. Women, on the other hand, often have atypical symptoms such as nausea, indigestion, fatigue, dizziness, or pain in the upper back. Heart attacks are often misdiagnosed in women because of this. Misdiagnosis could also be attributed to the thought of heart disease as a disease that primarily affects men. 45% of physicians surveyed did not realize that heart disease is the leading cause of mortality in women over 50. Mortality secondary to heart disease is falling in men but continues to rise in women. Now more women die secondary to heart disease each year than men.
The most basic test to evaluate heart disease is the electrocardiogram (EKG). It measures electrical activity within the heart. Breast tissue can distort the findings, making the test less accurate in women. An EKG is also used during a stress test, where the heart is evaluated during exercise. A more accurate test is the echocardiogram. An echocardiogram assesses blood flow through the chambers of the heart under ultrasound guidance. Angiogram is the best test to diagnose heart disease. It is an invasive test that involves threading a catheter from the femoral vein in the leg to the heart. Dye is then injected into the coronary vessels looking for blockages. Complications, such as strokes, can be caused by this procedure. Women with heart disease often have normal angiograms because their disease presents differently from men, as described above. This is also why women have not benefited as much as men from angioplasty. Angioplasty is a procedure treating artherosclerosis by dilating the affected artery with a balloon catheter and then a synthetic stent is placed in this area. The stent enables blood to pass unobstructed through the affected artery. A newer noninvasive test for heart disease is electron beam computed tomography (EBCT). Artherosclerotic plaques contain calcium, and an EBCT evaluates how much calcium has accumulated in the coronary vessels. Unfortunatey if the calcium count is high, an angiogram is often needed to see which blood vessels are affected and how severely they are affected.
Like all diseases, prevention is the best modality. Risks for heart disease are smoking, obesity, high cholesterol, high blood pressure (hypertension), inactivity, stress, and a family history. Laboratory values can also determine who is at more risk for heart disease. Elevated total cholesterol, LDL cholesterol, triglycerides, homocysteine, fibrinogen, C-reactive protein (CRP), and lipoprotein (a) levels are associated with heart disease. Smoking increases heart disease by three-fold over the general population. Smoking not only increases artherosclerosis but causes the plaques within the arteries to become unstable. Smoking also increases fibrinogen, a blood clotting protein produced by the liver. An excess of fibrinogen can cause hardening of the arterial walls, leading to loss of elasticity. Being overweight, especially at the waist, increases the risk for heart disease substantially. Women usually do not start to gain weight in their abdomen until after menopause. Prior to menopause, women are more prone to storing excess weight below the waist. Obesity also increases the chance of developing diabetes, which is another risk factor for heart disease. Fifty percent of women over the age of 45 have hypertension. Hypertension makes it harder for the heart to pump blood into the increased pressure within the arteries. Keeping total cholesterol, LDL cholesterol, and triglycerides low and HDL cholesterol high is very important. Low HDL cholesterol is more of an indicator for developing heart disease in women than in men. Homocysteine is an amino acid that rapidly rises after a woman reaches menopause. Elevation of homocysteine is correlated with arterial wall damage. Folate, vitamin B6, and vitamin B12 can reduce homocysteine levels. Inflammation has recently been shown to increase heart disease. CRP is an indicator of inflammation and people with higher CRP levels have been found to have more artherosclerosis. Research has shown that women with the highest levels of CRP were four times as likely to develop cardiovascular disease. Lipoprotein (a) is composed of apolipoprotein A and an LDL-C-like particle. Elevation of lipoprotein (a) is an indicator for possible artherosclerosis and coronary heart disease. Estrogen has been found to lower lipoprotein (a). See the chapter on estrogen to find out how estrogen is protective to the heart. Stress plays a role in heart disease and women have more stress related angina than men. Additionally depression increases the risk for heart disease and women have a higher incidence of depression. Unfortunately we cannot control our genes, but we can be aware of our risks and seek treatment for abnormal lab values and hypertension and maintain a healthy lifestyle.
Aspirin prevents platelets from clumping together to form blood clots. If symptoms of a heart attack occur, taking an aspirin immediately can save your life. Aspirin thins the blood enabling it to pass easier through the clogged blood vessel. Aspirin also reduces inflammation. C-reactive protein and interleukin-6 are substances associated with inflammation and are markers for cardiovascular disease. In January 2002 the U.S. Preventative Task Force concluded that aspirin could reduce the risk of heart attacks and strokes. Researchers showed that aspirin could prevent heart attacks by 28% when compared with a placebo. The side effects from aspirin are bleeding problems that usually occur in the gastrointestinal system. If there is no history of bleeding problems, all menopausal women should take a baby aspirin daily.
Cholesterol is essential to the body. The sex hormones are originally derived from cholesterol. The body naturally produces all the cholesterol it needs, so it is not required in the diet. Though cholesterol levels can rise secondary to our diets, cholesterol levels are mainly determined by heredity. Plants do not produce cholesterol, so no fruits or vegetables can increase our cholesterol intake. Animals, fish, and birds produce cholesterol so it is found in meats, egg yolks, and milk products. Saturated fats increase cholesterol levels. Low-density lipoprotein (LDL) cholesterol is commonly referred to as the “bad” cholesterol. LDL cholesterol is responsible for transporting cholesterol within the bloodstream. It then deposits the cholesterol on the lining of vessels forming cholesterol plaques. High-density lipoprotein (HDL) cholesterol is commonly referred to as the “good” cholesterol because it rids the body of cholesterol by transporting it to the liver. A high LDL/HDL ratio is more of an indicator for heart disease than high total cholesterol. The American Heart Association recommends keeping LDL cholesterol below 130, but newer evidence is showing that LDL should be kept even lower than this. The higher the HDL, the more protection you have. Cholesterol levels have been found to fluctuate and levels are often higher in the winter compared to the summer.
The first line of treatment for high cholesterol is lifestyle changes. It has been proven that cholesterol can be lowered with proper diet and exercise. Unfortunately some people only can lower their cholesterol slightly with lifestyle modifications and some people refuse to change. In 1987 the “statin” drugs were introduced, and they are now the leading class of prescription drug used in the U.S. They work by slowing the production of cholesterol in the liver and thus can substantially lower total cholesterol levels. They also work by removing LDL cholesterol from the blood, resulting in lower LDL cholesterol. They have also been shown to reduce C-reactive protein (CRP), which causes inflammation in blood vessels and other organs. In addition they increase HDL cholesterol and lower triglyceride levels. This class of drugs significanty reduces artherosclerosis, resulting in less coronary artery disease and less peripheral vascular disease. As a result they have decreased the risk of heart attacks and strokes by approximately 25%. Limited research has also shown that the “statins” may reduce the risk of Alzheimer’s disease, osteoporosis, rheumatoid arthritis, glaucoma, macular degeneration, and multiple sclerosis. The decrease in these diseases is probably secondary to the anti-inflammatory aspect of the “statins”. Some “statins” are more effective than others because have the ability to reduce inflammation more. The “statin” drugs have been shown to be very safe as well as effective, but they are expensive. Liver enzymes should be checked periodically since the drug works within the liver and1% of people will get liver problems. Other side effects are muscle pain and body aches. ApoA-1 Milano is a rare type of HDL cholesterol originally discovered in people living in Milan, Italy. ApoA-1 Milano has been found to significantly reduce the size of arthersclerotic plaques in a very short time period. A synthetic version of this HDL has been developed and has shown promising results when injected into patients. A new drug, Torcetrapid, has been found to increase HDL levels by nearly 50%.
Numerous natural remedies are used to treat hypercholesteremia. A recent study has shown that a diet rich in plant sterols, oats, barley, almonds, and soy proteins was just as effective as “statin” drugs at lowering cholesterol. Niacin (vitamin B3) has been used with success to lower cholesterol. It has been shown to lower LDL cholesterol by 20%, raise HDL cholesterol by 20%, and lower triglycerides. The main side effect from niacin is flushing. In multiple studies, garlic has been shown to reduce total cholesterol by 10%.