Insulin therapy in patients with type 2 diabetes mellitus

Diabetes mellitus is a disease of metabolic dysregulation, most notably abnormal glucose metabolism, accompanied by characteristic long-term complications. The complications that are specific to diabetes include retinopathy, nephropathy, and neuropathy. To achieve glycemic goals in patients with Type 2 diabetes when multiple pharmacologic agents are failing, the early introduction of insulin is key. Our objective is to assist clinicians in designing individualized management plans for insulin therapy in patients with Type 2 diabetes mellitus. We searched Medline, PubMed, journal articles, WHO publications, and reputable textbooks relating to diabetes mellitus and insulin therapy using publications from 1992 to 2016. With the progression of Type 2 diabetes, there is ultimately progressive loss of pancreatic beta-cell function and endogenous insulin secretion. At this stage, most patients require exogenous insulin therapy to achieve optimal glucose control. Choosing from the wide variety of glucose-lowering interventions currently available could be a challenge for the health-care provider and the patients in terms of effectiveness, tolerability, and cost of the various diabetes treatments. However, these should not be the case as risk reductions in long-term complications were related to the levels of glycemic control achieved, rather than to a specific glucose-lowering agent. The challenges of initiating and intensifying insulin therapy are quite enormous and could be daunting to health-care givers. Glycemic treatment should be stepwise with swift introduction of successive interventions after treatment failure (i.e., A1C ≥7.0%). Insulin should be initiated when A1C is ≥7.0% after 2-3 months of dual oral therapy.