New strategies for basal insulin treatment in type 2 diabetes mellitus

The clinical progression of type 2 diabetes mellitus (DM) is well understood. Glycemic control gradually deteriorates, and progression of DM eventually leads to an increased risk for microvascular and macrovascular complications. Reassessment of current insulin treatment strategies leading to restoration of glycemic control is essential to prevent or stop the progression of type 2 DM and its complications.

The purpose of this article was to review the importance of instituting a strategy of basal insulin therapy in patients with type 2 DM.

Relevant articles were obtained through an online search of PubMed and MEDLINE for literature published from 1990 to 2003. The search terms used were insulin therapy, combination oral therapy, treatment failure, glycemic control, insulin analogues, insulin glargine, basal insulin, and microvascular complications.

Large-scale intervention trials, such as the United Kingdom Prospective Diabetes Study (UKPDS), have reported that patients with type 2 DM treated with oral combination therapy are unable to maintain glycemic control. These observations have led to a reassessment of the role of insulin therapy in type 2 DM. The importance of tight glycemic control through the aggressive use of insulin early in the course of the disease is apparent from the UKPDS, Diabetes Control and Complications Trial, and other, smaller studies. Considerable evidence indicates that initiating a basal insulin-replacement strategy with an existing oral regimen can result in regaining glycemic control. Evidence emerging from recent studies indicates that use of intensive insulin therapy early in the course of the disease may have a positive clinical impact on outcome and slow the progression of complications. The availability of basal insulin analogues has expanded treatment options and improved the efficacy of therapeutic regimens for type 2 DM.

The available data suggest using an earlier transition from monotherapy to combination therapy to minimize disease-associated morbidity. The availability of new insulin analogues has expanded therapeutic options and offers the potential to enhance the efficacy of therapeutic regimens for type 2 DM as well as improve the ease and safety of treatment when glycosylated hemoglobin cannot be maintained <7% on > or =1 oral antidiabetic agent.