Insulin resistance: current concepts

Insulin sensitivity varies greatly within the general population; factors contributing to this variability include genetic pre-disposition, obesity, unfavorable body fat distribution, and lack of physical activity. Impaired insulin sensitivity may lead to impaired glucose tolerance and, even in individuals with modest insulin deficiency, to the development of type 2 diabetes mellitus. Of equal concern in patients with impaired insulin sensitivity is the development of the insulin resistance syndrome, in which hypertension, dyslipidemia, and impaired glucose tolerance form a cluster of risk factors for cardiovascular disease. Treatment of insulin resistance includes metformin and the thiazolidinedione troglitazone. Both drugs have been shown to be effective in the treatment of insulin resistance, one of the central abnormalities in type 2 diabetes mellitus. The purpose of this study was to review the current understanding of insulin resistance and its implications for the treatment of type 2 diabetes mellitus. To do this, a MEDLINE search of the clinical literature was conducted and the content analyzed.