Cardiovascular disease is the leading cause of death for adults in Canada. It develops as cholesterol and other cellular debris gradually builds up inside the blood vessels. This condition is called atherosclerosis, which is the narrowing of the arteries caused by the build-up of debris. As the blood vessels become narrower, the amount of blood going through the vessels becomes limited. The blood vessels responsible for oxygenating the heart itself are called the coronary arteries and disease to these blood vessels is called Coronary Artery Disease (CAD). CAD can lead to angina and heart attacks, which is discussed later in this chapter.
Top – Normal Coronary Artery; Bottom – Atherosclerosis
An inside look of a blood vessel that is partially and completely blocked due to atherosclerosis.
Blood pressure is the pressure of the blood against the inside walls of the blood vessels. Blood pressure can go up (high) or down (low). If someone experiences stress, his or her blood pressure can go up. If someone is more relaxed, his or her blood pressure goes down. In some people, blood pressure stays high. This constant state of high blood pressure is called hypertension. Over time, hypertension can damage the blood vessels causing them to lose their elasticity and become thick. It can also cause the heart to enlarge. Hypertension can cause serious problems that can result in heart attacks and strokes. High blood pressure can be controlled by losing weight, changing your diet and taking medications when prescribed. Blood pressure is measured at its highest and lowest points. Blood pressure is at its highest when the heart contracts to pump blood. This is called systolic pressure. When the heart is atrest between beats, the pressure falls and is called the diastolic pressure. A person’s blood pressure is expressed as these two values – the systolic “over” the diastolic. For example, normal blood pressure is considered to be 120/80 or 120 (systolic) over 80 (diastolic). It is important to “know your numbers” when it comes to high blood pressure. Blood pressure that is consistently more than 140/90 is considered high, but 130/80 is considered high if the person has diabetes.
Controlling risk factors can dramatically reduce cardiovascular disease. This usually means a change in lifestyle. A risk factor is an act or characteristic that increases the possibility of developing cardiovascular disease. Take the time to look at your own lifestyle and try to make positive changes.
Controllable Risk Factors
According to the Heart and Stroke Foundation of Canada, more than 47,000 Canadians will die prematurely each year due to smoking, and almost 8,000 non-smokers die each year from exposure to second-hand smoke. Smoking contributes to the build-up of plaque in the arteries, increases the risk of blood clots, reduces the oxygen in the blood, increases blood pressure and makes the heart work harder. Smoking also nearly doubles the risk of ischemic stroke.
Smoking is the number one cause of preventable death.
High Blood Pressure (Hypertension)
Hypertension affects one in five Canadians. Because there are no symptoms, many people who have high blood pressure don’t even know they have it. That is why it is called the “silent killer”. Extreme hypertension can cause a blood vessel in the brain to rupture resulting in a stroke.
Excessive Alcohol Consumption
Some evidence suggests that moderate amounts of alcohol, particularly red wine, can be good for your heart. But excessive alcohol consumption can increase blood pressure and contribute to the development of heart disease and stroke. Limit your alcohol intake to 1-2 drinks per day to a weekly maximum of 9 for women and 14 for men.
Diabetes increases the risk of high blood pressure, atherosclerosis,
coronary artery disease and stroke, particularly if blood sugar levels are poorly controlled. Uncontrolled diabetes can cause damage to the blood vessels, which can result in circulation problems.
High Blood Cholesterol
Cholesterol is one of the fats in your blood. High cholesterol can lead to a build-up of debris in the artery walls, causing atherosclerosis. There are two main types of cholesterol: Low-density lipoprotein (LDL) cholesterol and High-density lipoprotein (HDL). LDL is often called the “bad cholesterol” because high levels in the blood cause the build-up of plaque in the arteries. High-density lipoprotein (HDL) cholesterol is called the “good cholesterol” because it helps carry LDL-cholesterol away from the artery walls.
Those living with high levels of stress may have higher blood cholesterol, increased blood pressure or be at greater risk of developing atherosclerosis. High levels of stress can lead certain people to make unhealthy lifestyle choices such as overeating, smoking or drinking too much alcohol. Unhealthy lifestyle choices can increase the risk of developing heart disease and stroke.
Almost 60% of Canadian adults are either overweight or obese. By maintaining a healthy weight, you can considerably decrease your risk of heart disease and stroke and manage other conditions such as diabetes, hypertension and high cholesterol. You can maintain a healthy weight by eating a variety of healthy foods and becoming physically active.
Lack of Exercise
People who are not physically active are twice as likely to develop heart disease and stroke. Being physically active is a good way to maintain a healthy weight, reduce high blood pressure, lower cholesterol levels, manage stress and cut your risk of heart disease and stroke.
Uncontrollable Risk Factors
The risk of developing heart disease increases as a person gets older. Although a stroke can happen to someone at any age, the majority of strokes happen to people who are over the age of 65.
The risk of heart disease increases if immediate family members (parents, siblings or children) developed heart disease before the age of 55 or, in the case of females, before menopause. The risk of stroke increases if immediate family members had a stroke before the age of 65.
Gender and Menopause
Men over the age of 55 are at greater risk of heart disease. A woman’s risk of heart disease and stroke increases when they reach menopause. This is due to decreasing amounts of the hormone estrogen, which helps to protect the heart. Reduced estrogen levels may also increase body fat above the waist, have harmful effects on the way blood clots, and affect the way the body handles sugar, a precursor condition to diabetes. A menopausal woman may also show a tendency toward higher blood pressure.
Race or Ethnic Background
First Nations people and those of African or South Asian descent are more likely to have high blood pressure and diabetes and are therefore at greater risk of heart disease and stroke than the general population.