Treatment of Diabetes

Treatment of Diabetes

The theory of treatment of type I diabetes mellitus is to administer enough insulin so that the patient will have carbohydrate, fat, and protein metabolism that is as normal as possible. Insulin is available in several forms. “Regular” insulin has a duration of action that lasts from 3 to 8 hours, whereas other forms of insulin (pre-cipitated with zinc or with various protein derivatives) are absorbed slowly from the injection site and there-fore have effects that last as long as 10 to 48 hours. Ordi-narily, a patient with severe type I diabetes is given a single dose of one of the longer-acting insulins each day to increase overall carbohydrate metabolism through-out the day. Then additional quantities of regular insulin are given during the day at those times when the blood glucose level tends to rise too high, such as at mealtimes. Thus, each patient is provided with an individualized pattern of treatment.

In persons with type II diabetes, dieting and exercise are usually recommended in an attempt to induce weight loss and to reverse the insulin resistance. If this fails, drugs may be administered to increase insulin sen-sitivity or to stimulate increased production of insulin by the pancreas. In many persons, however, exogenous insulin must be used to regulate blood glucose.

In the past, the insulin used for treatment was derived from animal pancreata. However, human insulin pro-duced by the recombinant DNA process has become more widely used because some patients develop immu-nity and sensitization against animal insulin, thus limit-ing its effectiveness.

Relation of Treatment to Arteriosclerosis. Diabetic patients,mainly because of their high levels of circulating cho-lesterol and other lipids, develop atherosclerosis, arte-riosclerosis, severe coronary heart disease, and multiple microcirculatory lesions far more easily than do normal people. Indeed, those who have poorly controlled dia-betes throughout childhood are likely to die of heart disease in early adulthood.

In the early days of treating diabetes, the tendency was to severely reduce the carbohydrates in the diet so that the insulin requirements would be minimized. This procedure kept the blood glucose from increasing too high and attenuated loss of glucose in the urine, but it did not prevent many of the abnormalities of fat metab-olism. Consequently, the current tendency is to allow the patient an almost normal carbohydrate diet and to give large enough insulin to metabolize the carbohydrates. This decreases the rate of fat metabolism and depresses the high level of blood cholesterol.

Because the complications of diabetes—such as ath-erosclerosis, greatly increased susceptibility to infection, diabetic retinopathy, cataracts, hypertension, and chronic renal disease—are closely associated with the level of blood lipids as well as the level of blood glucose, most physicians also use lipid-lowering drugs to help prevent these disturbances.