Diabetes accentuates the risk of a heart attack by two to three times in men and three to seven times in women as there is a big link between diabetes and stroke. Besides blood glucose, patients with diabetes should also have blood pressure and cholesterol levels within the desirable range; they should not smoke, keep their weight at an optimum level and exercise regularly.
Stringent blood glucose control in diabetes reduces the risk of kidney failure, nerve degeneration, and blindness. The risk of heart disease and stroke is also reduced, but a very stringent regime may result in counter-productivity. It has been observed that attempting strict control of blood glucose, particularly in patients prone to excessive lowering of blood glucose (hypoglycaemia), may increase the risk of angina and rhythm disorders of the heart. Therefore, in such patients, it may be enough to achieve a glycosylated hemoglobin (HbA1c) of 6.5-7.0 per cent. HbA1c is a measure of average control of blood glucose over past three months or so. Reducing blood glucose per se may be more important than choosing a particular class of drugs for reducing blood glucose. Metformin is one medicine which has been shown to reduce the risk of heart disease in patients with diabetes. Therefore, it is the usual choice in newly-diagnosed diabetics when drug therapy is being contemplated.
When blood cholesterol level is high, it tends to deposit in arterial wall. Reduction of blood cholesterol may result in removal of cholesterol from arterial wall, thus improving the blood flow. Keeping cholesterol level under control by diet and exercise reduces the risk of heart attack. Excessive dietary cholesterol comes with food from animal sources including milk, milk products, and flesh foods. Reducing their intake controls the blood cholesterol levels to the desired level. Patients above 40 years of age, with diabetes, should also take statin drug treatment to reduce cholesterol level.
Blood pressure should be kept normal to prevent the adverse effects on the heart. For each decline of 1 mm Hg. in diastolic blood pressure, the risk of heart attacks is reduced by 2 to 3 percent. High blood pressure does not produce any symptoms as such and thus, it is called a `silent killer.’Since high blood pressure can only be determined by measurement, a regular 6 monthly checkup is essential after the age of 18. Anyone with a pressure persistently more than or equal to140/90 mm Hg needs drug treatment. Patients with diabetes generally require 2 or 3 antihypertensive drugs to control their blood pressure. Unless contraindicated, antihypertensive treatment of diabetics should include a class of drugs known as ACE inhibitors or ARBs that reduce the risk of kidney failure, besides BP reduction.
Smoking and tobacco chewing
The combination of diabetes and smoking is deadly as it noticeably increases the risk of heart disease as well as stroke and occlusion of lower limb arteries. The latter compromises blood flow in the legs and when fairly advanced, may cause gangrene and even limb amputation. Even non-smokers living in close company of smokers are more prone to heart attacks because of passive smoking. Quitting smoking has shown reduction in the risk of a heart attack by 50-70 percent. The risk reduction is almost halved in 2 years. Hence, not only is it necessary to abstain from tobacco, but also to avoid the company of smokers.
Brisk walking for about 30 to 45 minutes every day protects against heart attack. Walking is most beneficial when performed on empty stomach, 2-3 hours after meals. Early morning walks in winters are not desirable. Exposure to cold increases the work of the heart. Hence, morning walks in winters should be replaced with pre-lunch or late afternoon walks.
Obesity aggravates diabetes, high blood pressure and an increase in blood cholesterol. Thus, it adds a number of risk factors to the adverse health profile of a person. The risk of heart attack goes up if the waist circumference is more than 90 cm for men and 80 cm for women. Bringing down the weight to ideal level (or within 2 kilograms of ideal weight) reduces the risk of heart attack by 35 to 55 percent. Weight reduction should be done by a judicious combination of exercise and dieting. As a rule, one should not try to lose more than 2 kilograms per month.
Some patients with diabetes, who are at a high risk of heart attack, may benefit from a low dose of aspirin. A low dose (75 mg/day) reduces the risk of heart attack by about 33 percent. However, Aspirin should never be taken unless recommended by a doctor.
Dr. Peeyush Jain, Director and HOD, Non-invasive and Preventive Cardiology, Fortis Escorts Heart Institute.