Insulin: Either Alone or Combined with Oral Hypoglycemic Agents

Abstract

Non-insulin-dependent diabetes mellitus patients are those patients who do not require insulin for survival and do not have gestational, secondary, or malnutrition-related diabetes. They may require insulin to maintain good health. Therapy in NIDDM should attempt to reverse the coexisting defects of insulin deficiency and insulin resistance that lead to hepatic glucose over-production and diminished glucose tissue utilization. Both sulfonylureas and insulin can achieve near normal FPGs and HbA1c concentrations in mild to moderately severe NIDDM. Both can reduce insulin resistance and both increase insulin availability. Evidence exists, however, showing that prevention of post-prandial hyperglycemia, whose significance is unknown, may require soluble preprandial insulin. Treatment goals should be realistic and discussed with the patient. In younger patients, the aim should be to achieve normoglycemia, while in those who have other significant medical or social problems, or who are of advanced age, diabetic control may, out of necessity, need to be relaxed. At presentation a diet and exercise program should be initiated and the patient observed if clinically well. If diet fails to reduce the FPG below 108 mg/dl, additional therapy should be used. In mild to moderate NIDDM, sulfonylurea or basal insulin (given as once daily long- or intermediate-acting insulin) can be equally successful without the need for rigid dietary habits. More severe degrees of NIDDM or patients with sulfonylurea failure not caused by dietary indiscretion will require more complex insulin regimens. The socially dependent patient requiring insulin should have as simple a regimen as possible. The insulin-resistant patient undergoing surgery or with an intercurrent illness is most easily managed with a variable rate insulin infusion that allows prediction of subsequent subcutaneous insulin requirements. Combination insulin-sulfonylurea therapy should be reserved for patients failing to achieve acceptable glycemic control when insulin and sulphonylurea are used separately. It may improve control or lessen insulin requirements.