Insufficient blood supply to heart muscles usually results from narrowing of the artery (i.e. coronary artery). Deposition of lipid (fat) can cause thickening of the internal layer of the coronary artery leading to narrowing of its lumen (inner cavity). This process is known as atherosclerosis.
Factors that may hasten the process of atherosclerosis:
- Age – The risk of coronary artery disease tends to increase with age.
- Sex– It is more common in males. Women are at a lower risk as female hormones tend to protect them from coronary artery disease (before menopause).
- Family history– The chances of suffering from CHD increase if any close relatives have had CHD at an early age (below 50 years). Genetic factors, common dietary or smoking habits may cause increased susceptibility.
- Smoking– Smoking is a serious risk factor for CHD. In fact, the risk is directly related to the number of cigarettes smoked per day. The components of cigarette smoke cause temporary narrowing of blood vessels and increase the chance of clot formation there.
- High blood pressure– Blood pressure measurement is a simple method of detecting if a person is at high risk of developing coronary artery disease. The high pressure damages the lining of the arteries and accelerates the process of atherosclerosis. Moreover, heart has to work hard to pump the blood against increased pressure. This tends to increase the demand for oxygen in the heart muscles (thus, increasing the vulnerability to angina).
- Serum cholesterol– A rise in serum cholesterol level can hasten the process of atherosclerosis thus, increasing the risk of coronary heart disease. High LDL (low density lipoprotein) cholesterol level is associated with increased risk. The HDL (high density lipoprotein) cholesterol on the other hand, is protective and reduces the risk. In fact, the risk of developing coronary artery disease can be assessed by the HDL- LDL ratio.
- Diabetes-The risk of developing coronary artery disease is two to three times higher in diabetes. Control of blood glucose level decreases the risk of Coronary heart disease.
- Obesity-It is an important risk factor, both alone and in association with other risk factors like diabetes, high blood pressure, abnormal lipid profile. Individuals with “apple-shaped obesity” (i.e. most of the body fat around the stomach) are at higher risk of developing heart diseases.
- Alcohol– Heavy drinking (75g or more per day) increases the risk. The protective effect of moderate intake has not been fully substantiated.
- Personality– People with type A personality (hostile, restless and impatient nature) are more prone to heart disease.
- Lack of physical exercise– Sedentary habits may contribute towards obesity, high blood pressure, increased LDL cholesterol level, thereby, increasing the risk of Coronary heart disease.