Causes of Cardiovascular Disease

Cardiovascular disease (CVD) is caused by a combination of genetic and lifestyle factors. These are called risk factors, and many of them can be controlled. Those that can’t are called non-modifiable because they are not under your control.

Non-modifiable risk factors include:

• Age
• Gender
• Family history
• Ethnicity

Age

The Relationship Between Age and CVD

As you get older, your risk for cardiovascular disease increases. The changes your body undergoes in the aging process, while obvious from the outside — in the form of wrinkles, softer muscles, and grey hair — are not visible on the inside. But these internal changes — decreased bone density, narrowing arteries — are by far the more critical ones in terms of your health.

Major changes take place throughout your body as you age, whether you notice them or not. It’s a normal process, and nothing can stop or reverse it. Aging is linked to cardiovascular disease because major organs, such as the heart, also change as you grow older. Your heart functions less efficiently and your heart rate slows, pumping blood through the body at a slower rate. Even in the absence of disease, your heart muscle gets weaker and its pumping chambers may become stiff.

When Does the Risk for CVD Begin?

CVD becomes a bigger threat after the age of 55 for men and 65 for women, but this doesn’t mean your risk only begins at that age. Plaque buildup, which contributes to CVD, begins in childhood. The buildup becomes more severe with age because there has been more time for the arteries or vessels that deliver blood to the heart to become clogged.

Heart disease can also develop in young children through defects or infections at birth.

While the majority of heart disease deaths occur after age 55, the risk for CVD is set early on, through behaviours and lifestyle habits that begin in childhood and continue into adulthood. Obesity, unhealthy eating, and lack of physical activity are all major CVD risk factors and can begin before the age of 10. Unhealthy eating and lack of exercise can lead to childhood obesity, increasing the risk for heart disease. This is a major concern as obesity rates are rising among the young and the onset of cardiovascular disease is showing up earlier.

Gender

Overall, men have a higher risk for heart attack than women, but the difference narrows after women reach menopause. This is a result of a drop in estrogen levels, increasing the risk for women until it matches that of men.

After the age of 65, the risk for heart disease is about the same between the sexes when other risk factors are similar.

Risk for Men

• Men are at a greater risk for CVD than premenopausal women.
• Men are three to five times more likely to have CVD than women.

Risk for Women

• Cardiovascular risk increases significantly among women after the age of 65.
• After menopause, the risk for CVD increases to almost the same level as that of men, as a result of declining estrogen levels.
• Younger women who have diabetes are at the same risk for heart disease as men their age.
• Overall, women are more likely to die following a heart attack than men.

Symptoms

Both men and women experience the most common symptoms of a heart attack, but women may feel or respond to these symptoms differently. Women tend to put off seeking treatment because they are less likely to believe they’re actually having a heart attack.

Common heart attack symptoms include:

• Chest pain (including chest pressure, squeezing, fullness or pain, burning, or heaviness)
• Discomfort or pain in the neck, jaw, shoulder, arms, or back
• Shortness of breath
• Sweating
• Nausea
• Light-headedness

It’s important to take note of any other signs or symptoms that you think may be associated with a heart attack. Some people experience symptoms that are less common. For example, women will experience symptoms that are less definite, such as chest discomfort rather than chest pain.

In some cases, chest pain may not be the first sign of heart trouble. In others, some people, particularly women, report feeling less familiar symptoms up to a month or so before a heart attack occurs

Less common heart attack symptoms include:

• Unusual tiredness
• Sleep trouble
• Problems breathing
• Indigestion
• Anxiety

Diagnostic testing, warning signs, and symptoms may be felt differently by women. If you’re a woman who has already reached menopause, the Heart and Stroke Foundation suggests things you can do to prevent cardiovascular disease.

Family History

Your family history of cardiovascular disease is a strong indicator of your personal risk. A positive family history involving first-degree relatives is generally associated with a twofold increase in the risk for CVD.

Family history of CVD is the result of both genetic and behavioural factors. Adopting healthy lifestyle behaviours early on is key to reducing your overall CVD risk.

The Influence of Your Genes

Often referred to as your “genetics,” family history is the health information about you and your blood relatives. Family history is important in determining your risk for CVD because you and your blood relatives share the same genes. If a close family member — a parent, brother, or sister — developed heart disease before age 55 or, in the case of female relatives, before menopause, this indicates you may be at greater risk of developing CVD.

Your family history can influence your risk for heart disease in many ways. Genes control every aspect of the cardiovascular system, from the strength of the blood vessels to the way cells in the heart communicate. For many common conditions, such as coronary artery disease, stroke, atrial fibrillation, and diabetes, there are many risk factors — genetic, lifestyle, and environmental — that increase a person’s risk of developing the disease.

Genetic tests do not currently exist to measure individual risk for most cardiovascular diseases because the specific genetic factors are not yet fully understood. This makes family history, along with information about lifestyle choices and environment, one of the most important tools doctors have for assessing individual risk.

The Value of Family Screening

When a family member is diagnosed with cardiovascular disease, other family members may be encouraged to undergo screening to detect early stages of disease.

Aspects of family history that indicate a higher risk for heart disease include:

• Early onset of cardiovascular disease — for instance, coronary artery disease in men younger than 55 and women younger than 65
• Cardiovascular disease in two or three relatives on the same side of the family
• Late onset of cardiovascular disease on both sides of the family
• The loss of a family member to sudden cardiac death

With the appropriate medical treatment, people at increased risk for heart disease can delay the onset and lessen the severity of the disease.

• Learn more about cardiac conditions with a strong genetic component.

Action Tips

• Make sure your family doctor knows your family history.
• Discuss risk and lifestyle with your children and siblings.

Certain diseases are more common in some families than in others. Your own risk may be higher than average because of the genes you inherited. Or it may be high because the members of your family all tend to make similar lifestyle choices and hold similar beliefs about diet and exercise, as families will do. If you have a family history of CVD, you should try to make lifestyle changes to reduce your risk.

If you have a family history of CVD, you can’t change your genetics, but there’s plenty you can do to prevent or avoid the disease. Knowing you’re at increased risk can motivate you to take precautions to control other risk factors.

Ethnicity

Ethnicity describes people with the same cultural background or geographical ancestry. It’s also referred to as race. The ethnic group or race you belong to can have a genetic makeup and environmental influences that predispose its members to CVD.

People of the same ethnicity share many of the same genes, which is why family history and ethnicity are so closely linked. People with similar ancestry may pass down similar mutations in their genes.

First Nations people and people of African or Asian descent are at higher risk of developing heart disease.

Why These Groups Are at Higher Risk

First Nations

• High blood pressure and diabetes are more common in this population.
• First Nations people are up to eight times more likely to develop diabetes than other Canadian adults.
• Both high blood pressure and diabetes are of great concern as they are risk factors for cardiovascular disease.

People of African Descent

• High blood pressure and diabetes are more common in this population.
• African Canadian women, in particular, are more commonly affected.

People of Asian Descent

• High blood pressure and diabetes are more common in this population.
• In this group, culture is a big part of people’s lives, and dietary habits — including high saturated fat and sodium foods — are part of that culture.
• People of Asian descent commonly face language barriers, which can keep them from understanding the CVD risks they face.
• Language barriers may also keep Asian people from completely understanding healthy-heart awareness campaigns and messages.

Studies indicate that people from minority populations are less aware that smoking, high cholesterol, and family history increase their risk for heart disease. Awareness levels can impact a person’s decision about whether to start making healthy lifestyle changes.

In some instances, certain ethnic populations are simply more prone or sensitive to specific risk factors for less obvious reasons. Researchers are trying to identify exact causes, but it may very well be that intolerances to things such as salt (sodium) or sugars are genetic and non-modifiable, unrelated to lifestyle or cultural practice.

References

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