IGF-Binding Protein-1 Levels Are Related to Insulin-Mediated Glucose Disposal and Are a Potential Serum Marker of Insulin Resistance

We were interested in the article of Maddux et al. (1) in which they found a correlation coefficient of 0.75 for the relationship of IGF-binding protein (IGFBP)-1 with insulin sensitivity. Often, the homeostasis model assessment of insulin resistance (HOMA-IR) or other assessments such as the Stumvoll Index (2) are used. Because hepatic production of IGFBP-1 is under direct inhibitory influence of insulin, plasma IGFBP-1 levels could potentially be of use …