Coronary heart disease is a major killing disease in the West. In Britain it is responsible for the death of two out of five men in middle age and a total in excess of 100,000 annually. Men are more susceptible to the disease than women who appear to be protected at least until the menopause.
Coronary heart disease is a general term which covers a variety of conditions. Blood vessels lose elasticity as they age and they narrow. Further narrowing can be caused by fibrous plaques which fill with fatty material. As these deposits build up, blood may not be able to circulate efficiently to the tissues which need oxygen for their metabolism. Further risk is involved as blood has a greater tendency to clot in these occluded areas and this can cause a ceasing of bloodflow. If this happens in the coronary vessels an important part of heart muscle may be prevented from functioning. Severe blockage results in a fatal stroke or milder attacks result in angina (heart pain).
Greater fatty deposits in blood vessels are found in people who have high levels of cholesterol and fat in their blood, so these people are more likely to suffer an attack. High dietary intakes of cholesterol and saturated fat are firmly linked to blood levels and decreasing intake of these foods has been shown to cause a decrease in blood levels and risk in some groups of people. Decreasing fat intake and substituting the remaining animal fat with polyunsaturated fats seems to have the greatest effect on decreasing blood fat levels but its use therapeutically is not a guaranteed method of preventing the disease although it does reduce the risk. Dietary restriction of cholesterol and fats and the substitution of fats have been recommended, but the real mechanisms which cause attacks remain a mystery. Carbohydrates, especially sugar can cause raised blood fat levels in some people so for them restriction of these may be effective.
Nondietary factors also influence a person’s chance of coronary heart disease. Smoking involves the inhalation of toxic chemicals which can affect the tendency of the blood to clot and the permeability of blood vessel walls. People with high blood pressure are also at high risk.
Those in exacting jobs experience mental pressure which can lead to hormonal and metabolic responses which create irreversible changes in blood fats, pressure and vessels. People with inactive jobs are more prone to heart attack than their more active counterparts. The increase in coronary heart disease is correlated with the increase in sale of television licences which shows not only that this disease is associated with affluence but may be an indictment of the inactive way we spend our leisure time.
If we want to live for our full three score years and ten we stand a better chance if our blood lipids and pressure are within normal limits, if we refrain from smoking and if we alleviate our mental stress with more physically active lifestyles.