Metformin is a unique drug

Treating prediabetes with metformin” (April 2009) was a very good article.1 Prediabetes—either impaired fasting glucose, impaired glucose tolerance, or both—can result in overt diabetes within a few years. The key pathophysiologic factor for prediabetes and the subsequent onset of type 2 diabetes is insulin resistance. In normal subjects, insulin stimulates glucose uptake by skeletal muscle cells, adipose tissue, and hepatocytes. In insulin resistance, these tissues fail to uptake glucose molecules and because of compensatory mechanisms more and more insulin is secreted by β-cells, causing hyperinsulinemia. As a result of continuous pressure, β-cells ultimately fail to produce an adequate insulin response to glucose, leading to type 2 diabetes. Lifestyle modifications, such as diet and physical exercise, offer great value to the reduction of insulin resistance and the prevention of new onset type 2 diabetes. And as a drug therapy, metformin, by reducing hepatic glucose production and increasing insulin sensitivity in peripheral tissue, can substantially reduce the process of transforming prediabetes to type 2 diabetes. Insulin resistance is also referred to as insulin resistance syndrome, which includes type 2 diabetes, hypertension, dyslipidemia, obesity, and others. Metformin is not only effective in preventing onset of overt diabetes, but also might have preventive value on hypertension, dyslipidemia, and obesity. I think every patient who is diagnosed with prediabetes should start metformin along with lifestyle interventions to reduce onset of not only type 2 diabetes, but other metabolic disorders.

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