Fasting insulin as a measure of insulin resistance

The most effective technique to assess insulin sensitivity is the hyperinsulinemic euglycemic clamp, but this is time-consuming, expensive and stressful to patients. While fasting insulin concentrations are often used as an alternative measurement, there is some evidence that fasting hyperinsulinemia may itself cause cardiometabolic disease. This study by de Rooij et al. aimed to distinguish between the relative contributions of fasting insulin and insulin resistance to cardiometabolic risk and preclinical atherosclerosis. The investigators used participants from the Relationship between Insulin Sensitivity and Cardiovascular (RISC) disease study cohort of 1326 European, non-diabetic, healthy men and women and performed oral glucose tolerance tests and hyperinsulinemic euglycemic clamps. Cardiometabolic risk was assessed by the prevalence of the metabolic syndrome in 1177 participants and carotid artery intima media thickness measured by ultrasound.

Fasting insulin, a test often used for its simplicity and practicality, was found to have a stronger association with cardiometabolic risk and atherosclerosis in this healthy population than with hyperinsulinemic euglycemic clamp derived insulin sensitivity. de Rooij, S.R., Dekker, J.M., Kozakova, M., Mitrakou, A., Melander, O., Gabriel, R., Guidone, C., Højlund, K., Murphy, M.S., Nijpels, G., and the RISC Group Investigators. Fasting insulin has a stronger association with an adverse cardiometabolic risk profile than insulin resistance: the RISC study. European Journal of Endocrinology 161 223-230, DOI: 10.1530/EJE-09-0058