Risk Factors for Cardiovascular Disease

Cardiovascular Health and Risk

What are modifiable risk factors for CVDs?

Risk factors that can be changed through lifestyle choices, reducing a person's risk of developing cardiovascular disease.

What are the main modifiable risk factors for CVDs?

Smoking, inactivity, high blood pressure and factors associated with diet.

Why do differences in CVD rates between countries suggest lifestyle factors are important?

Non-modifiable factors such as age, genetics and gender exist worldwide, but CVD rates vary greatly between countries, suggesting lifestyle and environmental factors also affect risk.

How is atherosclerosis linked to cardiovascular disease?

Atherosclerosis narrows and hardens arteries, increasing the risk of cardiovascular diseases such as coronary heart disease, heart attacks and strokes.

How does smoking increase the risk of atherosclerosis?

Substances in tobacco smoke damage the endothelial lining of arteries, making plaque formation more likely.

How does smoking affect the diameter of arteries?

Smoking can cause arteries to narrow.

How does smoking affect blood pressure?

Smoking narrows blood vessels, which increases resistance to blood flow and raises blood pressure.

How does raised blood pressure caused by smoking increase atherosclerosis risk?

Higher pressure can damage the arterial endothelium, making plaque formation more likely.

What evidence links smoking with atherosclerosis?

Epidemiological studies show smokers are much more likely to develop atherosclerosis than similar non-smokers.

Why does evidence that smokers have more coronary artery disease than non-smokers support smoking as a risk factor?

A higher proportion of disease among smokers shows an association between smoking and increased cardiovascular risk.

Does an association between smoking and CVD automatically prove causation?

No. Correlation alone does not prove causation, although additional biological and epidemiological evidence can strengthen evidence for a causal relationship.

Why is inactivity a risk factor for CVD?

Inactivity is associated with obesity, diabetes, high blood pressure and unhealthy blood lipid levels, all of which increase CVD risk.

How does regular exercise affect blood pressure?

Regular exercise helps lower blood pressure.

How does regular exercise affect obesity and diabetes risk?

It helps maintain a healthy body mass and reduces the risk of obesity and type 2 diabetes.

How does regular exercise affect blood cholesterol?

It can help lower harmful blood cholesterol levels and improve the balance of blood lipoproteins.

How does regular exercise affect stress?

It can reduce stress, which can help lower cardiovascular risk.

How can exercise reduce the risk of atherosclerosis?

Exercise reduces several risk factors and can reduce plaque formation and help existing plaques remain more stable and less likely to rupture.

What did studies of physically active adults suggest about CVD risk?

People who exercised regularly generally had a lower risk of atherosclerosis, CVD and cardiovascular mortality than inactive people.

What relationship has been found between inactivity and obesity?

Higher levels of inactivity are associated with an increased risk of obesity.

What relationship has been found between inactivity and type 2 diabetes?

Higher levels of inactivity are associated with an increased risk of type 2 diabetes.

What relationship has been found between inactivity and high blood pressure?

Higher levels of inactivity are associated with an increased risk of high blood pressure.

What is systolic blood pressure?

The pressure in the arteries when the ventricles contract and force blood out of the heart.

What is a typical healthy systolic blood pressure given in the textbook?

About 120 mmHg.

What is diastolic blood pressure?

The pressure in the arteries when the heart is relaxed and filling with blood during diastole.

What is a typical healthy diastolic blood pressure given in the textbook?

About 80 mmHg.

What does a blood pressure reading of 120/80 mmHg represent?

Approximately 120 mmHg systolic pressure over 80 mmHg diastolic pressure.

Why does blood pressure naturally vary during the day?

It changes with factors such as activity, stress and the changing demands placed on the cardiovascular system.

What is high blood pressure?

Blood pressure that is regularly above the healthy range.

What is hypertension?

Persistently high blood pressure, which increases the risk of developing cardiovascular disease.

What blood pressure does the textbook use to indicate hypertension?

Blood pressure regularly above about 140/90 mmHg.

How can atherosclerosis cause high blood pressure?

Plaques narrow the lumen and reduce arterial elasticity, increasing resistance to blood flow and therefore increasing blood pressure.

Why can high blood pressure be a sign of atherosclerosis?

Narrowing and stiffening of arteries caused by plaque increases resistance and therefore raises blood pressure.

How can high blood pressure contribute to atherosclerosis?

Constant high pressure increases damage to the endothelial lining of arteries, making plaque formation more likely.

What positive feedback relationship can occur between hypertension and atherosclerosis?

Atherosclerosis narrows and stiffens arteries, raising blood pressure; the raised pressure causes further endothelial damage, encouraging more atherosclerosis.

How does smoking contribute to high blood pressure?

Smoking causes blood vessels to narrow, increasing resistance to blood flow.

How can obesity contribute to high blood pressure?

Obesity is associated with physiological changes that increase cardiovascular strain and the likelihood of hypertension.

How can inactivity contribute to high blood pressure?

Lack of regular exercise increases the risk of obesity and poor cardiovascular health, making hypertension more likely.

How can a high-salt diet contribute to high blood pressure?

High salt intake can increase water retention and blood volume, contributing to increased blood pressure.

How can stress contribute to high blood pressure?

Stress responses can increase heart activity and cause blood vessels to narrow, increasing blood pressure.

Why is persistent high blood pressure dangerous?

It can damage arterial linings, promote atherosclerosis and increase the risk of cardiovascular disease.

How can someone with high blood pressure reduce their CVD risk?

By making appropriate lifestyle changes and, when necessary, using prescribed medication to lower blood pressure.

Does being overweight necessarily directly cause CVD?

Not necessarily. Evidence suggests body weight alone may be less informative than factors such as fat distribution, physical activity and blood lipid levels.

What factors may be better predictors of future CVD than body weight alone?

Where fat is stored on the body, how much exercise a person does and the levels and types of fats or lipoproteins in their blood.

How can being overweight indirectly increase CVD risk?

It can increase the likelihood of conditions such as high blood pressure and type 2 diabetes, which directly increase cardiovascular risk.

How does high blood pressure associated with excess weight increase atherosclerosis risk?

It increases damage to blood vessel linings, making plaque formation more likely.

How does type 2 diabetes increase atherosclerosis risk?

It can damage the lining of blood vessels, increasing the likelihood of plaque formation.

Why is the relationship between diet and CVD difficult to investigate?

Human diets are complex and many other lifestyle and genetic variables can influence cardiovascular risk, making individual effects difficult to separate.

What does current evidence suggest about diet and atherosclerosis prevention?

A balanced diet containing a variety of foods and plenty of fruit and vegetables can help reduce the risk of atherosclerosis.

Why can scientists find conflicting evidence about diet and CVD?

Different studies may investigate different foods, populations and variables, and many confounding factors can affect the results.

Why is atherosclerosis described as a multifactorial disease?

There is no single cause; many genetic, physiological and lifestyle factors interact to influence the probability of developing it.

Does one risk factor guarantee that someone will develop atherosclerosis?

No. Risk factors increase probability but do not guarantee that the disease will develop.

Why can combinations of risk factors be particularly important?

Different risk factors can interact and together increase CVD risk more than considering each factor separately.

How can smoking affect CVD risk through more than one mechanism?

It can damage arterial endothelium, narrow blood vessels, increase blood pressure and alter blood lipoproteins.

Why is it important to consider links between CVD risk factors?

One risk factor can affect another, so their combined effects may substantially increase overall cardiovascular risk.

How can smoking and high blood pressure interact to increase atherosclerosis risk?

Smoking narrows and damages blood vessels and can increase blood pressure; the increased pressure causes further endothelial damage and promotes plaque formation.

What general lifestyle measures can help prevent atherosclerosis and CVD?

Not smoking, eating a balanced diet, maintaining a healthy body mass, exercising regularly and controlling blood pressure.

Why can eating plenty of fruit and vegetables help reduce CVD risk?

They form part of a balanced diet associated with maintaining cardiovascular health and reducing atherosclerosis risk.

Why is maintaining a healthy weight useful for preventing CVD?

It helps reduce the risk of hypertension and type 2 diabetes, both of which increase CVD risk.

Why is regular exercise recommended for preventing CVD?

It helps control blood pressure, body mass, diabetes risk, blood lipid levels and stress.

Why is it important to reduce constant stress when trying to prevent CVD?

Chronic stress can contribute to raised blood pressure and other cardiovascular risk factors.

Why is early prevention of atherosclerosis important?

Risk factors and early signs of arterial changes may already be present in young people, and atherosclerosis develops progressively over time.

Why can advice about preventing CVD change over time?

New epidemiological evidence can change scientists' understanding of which factors increase or decrease cardiovascular risk.

What type of evidence is commonly used to identify CVD risk factors?

Epidemiological studies comparing disease rates with lifestyle, physiological and other factors in populations.

Why should CVD risk-factor studies use large samples?

Large samples reduce the effect of individual variation and make patterns and associations easier to identify.

Why should samples in CVD studies be representative?

So the results can be applied more reliably to the wider population.

Why must age be considered when comparing smoking and coronary artery disease?

CVD risk naturally changes with age, so age could otherwise confound the relationship between smoking and disease.

Why should gender be considered when analysing CVD data?

CVD risk differs between males and females, particularly at some ages, so gender can influence the results independently of another risk factor.

What is an important limitation when comparing CVD rates between countries?

Countries differ in many factors including diet, healthcare, smoking, physical activity, wealth, genetics and population age structure, so differences cannot automatically be attributed to one cause.

What is meant by a lifestyle risk factor?

A behaviour or lifestyle characteristic that affects the probability of developing a disease and can potentially be changed.

Define high blood pressure.

Blood pressure that is regularly above about 140/90 mmHg and increases the risk of developing CVD.

Define hypertension.

Persistently raised blood pressure, regularly measuring above about 140/90 mmHg, which increases CVD risk.

Explain how smoking can lead to atherosclerosis.

Chemicals in tobacco smoke damage the arterial endothelium and can narrow blood vessels and raise blood pressure. Endothelial damage promotes an inflammatory response and plaque formation, increasing atherosclerosis risk.

Explain how inactivity increases CVD risk.

Inactivity increases the likelihood of obesity, type 2 diabetes and hypertension and can adversely affect blood lipid levels. These factors increase atherosclerosis and CVD risk.

Explain how high blood pressure can lead to atherosclerosis.

High pressure places greater mechanical stress on arterial walls, damaging the endothelium. This encourages inflammatory responses and plaque formation, leading to atherosclerosis.

Explain how atherosclerosis can cause high blood pressure.

Plaques narrow arterial lumens and make artery walls less elastic. This increases resistance to blood flow, so greater pressure is required to move blood through the arteries.

Explain how being overweight can indirectly increase CVD risk.

Being overweight is associated with increased risks of hypertension and type 2 diabetes. These can damage arterial endothelium and promote atherosclerosis.

Explain why CVD prevention should focus on several lifestyle factors rather than only one.

CVD is multifactorial, so smoking, inactivity, diet, blood pressure, body composition and other factors can interact. Improving several modifiable factors can therefore reduce overall risk more effectively.

What is the difference between a modifiable and a non-modifiable risk factor?

A modifiable risk factor can be changed, such as smoking or inactivity, whereas a non-modifiable risk factor cannot be changed, such as age or inherited genes.

Give two examples of non-modifiable risk factors for CVD.

Age and genetics. Gender is another example.

Give two examples of modifiable risk factors for CVD.

Smoking and inactivity. High blood pressure and aspects of diet are other examples.