Delaying the onset of type 2 diabetes mellitus in patients with prediabetes.

The frequency of type 2 diabetes mellitus is increasing at an alarming rate. Prediabetes, also referred to as impaired glucose tolerance (IGT) and/or impaired fasting glucose, is a major risk factor for development of type 2 diabetes mellitus. In addition, IGT has been associated with an increased risk of cardiovascular disease and mortality. Several studies have measured the effects of various interventions in patients with IGT on the development of type 2 diabetes mellitus. Intensive lifestyle modifications through alterations in diet and improvement in exercise have delayed the development of type 2 diabetes mellitus by 58% in patients with IGT. Therapy with metformin, troglitazone, or acarbose also has reduced the progression of IGT to diabetes mellitus by 31%, 49% and 25%, respectively. The mechanisms by which lifestyle interventions and drugs reduce the progression may be through alterations in insulin sensitivity. The American Diabetes Association recommends screening for prediabetes in patients who are 45 years or older and those with a body mass index of 25 kg/m2 or greater who have additional diabetes mellitus risk factors. Pharmacists can promote awareness, counsel patients on intervention strategies to delay the onset of diabetes mellitus, and screen high-risk patients.