Intensive insulin regimens: evidence for benefit

It is now well established that the risk of experiencing diabetic complications is dependent on the degree of glycaemic control in patients with diabetes. Clinical trials such as the Diabetes Control and Complications Trial (DCCT) and Kumamoto study have demonstrated that tight glycaemic control achieved with intensive insulin regimens can reduce the risk of developing or progressing retinopathy, nephropathy or neuropathy in patients with type I or II diabetes. The EDIC trial, a follow-up to the DCCT, has shown that the previous degree and duration of glycaemic exposure are also important determinants of risk of developing microvascular diabetic complications. It appears that beneficial outcomes with regard to microvascular risk can be achieved with the improved metabolic control associated with intensive insulin regimens; however, data examining the effect of intensive insulin regimens on macrovascular risk is inconclusive. Epidemiological data highlight the role of postprandial blood glucose in cardiovascular disease and mortality, especially in patients with type II diabetes. Consequently, it is logical to suppose that insulin regimens that control both fasting plasma glucose and postprandial glucose excursions should also achieve the best macrovascular risk outcomes and there are some data that suggest this. Intensive insulin treatment can also improve prognosis in acute clinical situations such as myocardial infarction in patients with or without diabetes. In summary, intensive insulin regimens achieve strict metabolic control in patients with diabetes and could offer the best possible outcomes with regard to microvascular and macrovascular complications.