Angina Risk Factors

What is Angina?

According to the Mayo Clinic and the Cleveland Clinic, angina, also known as angina pectoris, is a kind of chest pain caused by restricted blood flow to the heart. It is most often a symptom of coronary artery disease (CAD). 

Your blood carries oxygen and other things vital for the survival of your heart muscle. When your heart muscle doesn’t get enough blood flow going to it, this is called ischemia. This can be caused when the arteries leading to the heart harden and develop fatty deposits inside, which narrow or block them (atherosclerosis).

Angina can also be a sign of coronary microvascular disease (MVD), especially in women, and coronary spasms.

The most common form of angina is called stable angina. It usually happens when you exert yourself and stabilizes when you take rest, e.g., pain that comes on when you're walking uphill or in the cold weather may be angina. It is usually short-lived (5 minutes or less), comes on predictably (e.g., when your heart is working harder during activity) and usually gets better more quickly if you use angina medication.

Conversely, unstable angina can be the precursor to a heart attack and constitutes a medical emergency. It occurs when fatty deposits in your blood vessels, called plaques, rupture, or a blood clot suddenly forms, abruptly blocking or narrowing an artery and reducing critical blood flow through it. It can occur even at rest, will feel different to your usual angina symptoms, comes on unexpectedly, is usually more severe and lasts maybe 30 minutes or even longer. Angina medication might not improve your symptoms if you have unstable angina.

You should consult your doctor urgently if you have symptoms so that they can determine which sort of angina you have.  

The primary angina symptom is chest pain, often described as a severe pressure, squeezing, burning or full sensation in the chest. The pain may radiate to the arms, neck, jaw, shoulder or back. Other symptoms that may be present with angina include:

• Dizziness
• Fatigue
• Nausea
• Shortness of breath
• Heart palpitations
• Sweating

Women may experience different angina symptoms from men. For example, chest pain may feel like stabbing instead of pressure. Other signs may include abdominal pain and discomfort in the neck, jaw or back.

Risk Factors for Angina

• Nutrition: It is important to eat a healthy diet especially if you have angina. Your diet should include an abundance of fresh fruits and vegetables, lean proteins like chicken or fish and low-fat dairy products such as skimmed milk. 

Fried, fatty, sugary and processed foods, and foods high in sodium should be avoided. Such foods are generally rich in saturated, hydrogenated and/or partially hydrogenated fats which can make angina worse. High circulating levels of cholesterol and triglycerides (fats) in the bloodstream are major contributors to fatty deposits that narrow or block arteries, particularly LDL (bad) cholesterol, which increases the risk of angina and heart attacks.

• Physical Activity: Moderate to strenuous physical activity can trigger stable angina symptoms. However, it is vitally important to stay active if you have angina. 

The risk of worsening your symptoms is low if you build up your activity level gradually, keep your angina medication (e.g., a glyceryl trinitrate (GTN) spray) handy and if needed, use your medication before exercise. 

The British Heart Foundation has some great advice on how to safely exercise when you have angina. 

• Smoking: Smoking is very harmful to your heart and a major cause of heart and circulatory diseases. Chemicals in the smoke make the walls of your arteries sticky, encouraging the buildup of fatty deposits which gradually narrow and block the blood vessels around and to the heart muscle. This can lead to angina, or much worse, a heart attack. 

Smoking can also clog the arteries leading to your brain, causing a stroke.  The nicotine in smoke causes an instantaneous rise in heart rate and blood pressure, both of which may precipitate an angina attack. If you have angina or any heart problem, quitting smoking should be a top priority.

1. Alcohol: Alcohol consumption can increase the risk of high blood pressure, obesity and type 2 diabetes, all of which can impact the risk of angina and other heart problems.  Heavy, sustained drinking can weaken the heart muscle, a condition known as cardiomyopathy. Alcohol can also interact with heart medications and may render them less effective. Cutting down on alcohol can significantly improve your risk of heart problems and can reduce the risk of angina attacks. According to the BHF, the Chief Medical Officers of the UK states that safe alcohol consumption levels are 14 units per week or less, spread over at least three days.
2. High Blood Pressure: Prolonged high blood pressure forces your heart to work harder to pump blood around the body. Healthy arteries are flexible, strong and elastic. High blood pressure causes damage to the walls of the arteries, promoting the  development of atherosclerosis. Eventually, the damaged, atherosclerotic arteries become less elastic in nature and this restricts blood flow, leading to angina.
3. Diabetes: Diabetes increases the risk of Coronary Artery Disease (CAD), which leads to angina. Persistent high blood sugar levels can damage the linings of the arteries, leading to atherosclerosis, and the excess glucose can gum the red blood cells together, causing reduced blood flow and blockages in the blood vessels.
4. Hydration: Staying hydrated is important to your heart health. When you become dehydrated, your total blood volume decreases, forcing your heart to beat faster and work harder, increasing your blood pressure. Dehydration also causes the body to retain sodium, which increases the thickness (viscosity) of the blood, forcing the heart to work even harder. These factors can contribute to heart diseases such as angina. According to The Heart Foundation, optimal hydration requires 2.7 litres total fluid intake for a woman and 3.7 litres, per day, for a man.
5. Sleep. According to the BHF, sleeping for more than seven hours a night or less than six hours may be linked to an increased risk of heart disease, but this was based on limited research. 

Interrupted sleep certainly evokes a fast rise in heart rate and blood pressure that can cause an angina episode. Lower sleep quality and sleep deprivation are associated with chest pain and poor heart health according to clinical studies. This effect is magnified if you suffer from obstructive sleep apnoea (OSA) since the obstruction of the airway causes fragmented sleep. Other sleep disorders, such as restless leg syndrome, have also been linked to heart diseases. 

• Weight/BMI: Obesity (having a BMI greater than 35) is linked with high blood cholesterol levels, high blood pressure and diabetes, all of which increase your risk of angina and heart disease. If you're overweight, your heart has to work harder to supply blood to the body. Eating a healthier diet and increasing physical activity should help you lose weight and thus lower the risk of angina attacks.

• Gender: Men have a slightly lower risk of angina than women up to the age of 64, but this reverses after this age. The prevalence of stable angina in the UK in 2020 was 5-7% in women and 4-7% in men aged 45-64, rising to 10-12% in women and 12-14% in men aged 65-84 (BHF).

• Ethnicity: According to Bhopal et al (2012), in the UK, the highest risk of chest pain and angina was in South Asian men and women. The lowest risk was found in Chinese, Afro-Caribbean and white Caucasian men and women, with Afro-Caribbeans being the lowest of all (George et al 2017).

• Stress: Stress can increase your risk of angina and heart attacks. Too much stress can raise your blood pressure. Surges of hormones like adrenaline produced during stress can narrow your arteries and worsen angina. However, according to the BHF, the primary effect of stress on angina is mediated by an increased propensity to adopt unhealthy habits such as smoking or drinking as a result of that stress.

• Family History of Heart Disease: If a family member has coronary artery disease or has had a heart attack, you're at a greater risk of developing angina. This is because genes we inherit from our parents can affect the risk of high blood pressure, high cholesterol and other predisposing factors to heart disease.

• Age: Risk of angina generally increases with age in both men and women, being roughly doubled in those aged 65 or over compared with younger people, and tripled (men) and quintupled (women) in those over 75 according to data from the BHF.

There are many risk factors for angina. It is important to remain physically active and to eat healthily in order to mitigate the risk of angina episodes. High blood pressure and diabetes, from a variety of causes, smoking, alcohol, dehydration, stress, lack of sleep all contribute. Lastly, age, body mass index (BMI), gender and ethnicity and genetics all impact the risk of angina.  Many of these risk factors are interconnected.