Heartstricken with age
Coronary Heart Diseases (CHD) such as atherosclerosis, myocardial infarction, angina pectoris and strokes, are the leading cause of death among elderly persons. Eighty per cent of all deaths due to CHD occur in persons over 65.
Most common forms of CHD, such as atherosclerosis, are caused by structural and functional changes in the artery walls: abnormal constriction, enhanced interaction of blood cells with the vessel wall, and unwarranted activation of coagulation mechanisms. If the affected vessels carry blood to the heart, the supply of oxygen and the removal of metabolites (substances produced during or necessary to metabolism) can be so seriously impaired that the tired muscles begin to ache -- the much-feared angina.
There are several risk factors associated with CHD, hypertension (high blood pressure) and elevated levels of cholesterol and blood sugar being the common ones.
Aspirin, a cheap drug usually administered for headaches, has finally been accepted after a long debate as a wonder preventive drug. According to the largest series of trials of a drug ever undertaken -- involving 140,000 patients from 29 countries -- a small daily intake of the painkiller could save more than 100,000 lives a year around the world.
James Scott at the Hammersmith Hospital in London and others have found that fat deposition in arteries is due to overzealous macrophages, the scavenger molecules of the immune system. They zero in on a common protein called apolipoprotein-B (apoB) which ferries fat molecules from one part of the body to another. They leave normal apoB particles, but chew them up if they are damaged and dump the fat molecules carried on the artery walls.
Scott's team has identified a faulty gene which controls the synthesis of apoB. He believes that a drug that mimics this gene can block the synthesis of apoB and lower the deposition of fat inside arteries.