Diagnostic methods of insulin resistance in a pediatric population

Obesity is the main risk factor for insulin resistance (IR) in the pediatric population. IR represents a link between obesity and other metabolic complications such as type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Therefore, accurate diagnosis and early intervention may reduce the incidence of T2DM and CVD in at-risk individuals. In this study we describe the techniques used to assess insulin sensitivity in pediatric populations. We also describe in detail three diagnostic tests: the glucose clamp technique, which represents the gold standard to determine tissue insulin sensitivity and insulin secretion; HOMA and QUICKI, which are indexes obtained from fasting glucose and insulin concentrations; and ISI-Composite, obtained from an oral glucose tolerance test, which provides additional information on glucose metabolism after an oral glucose load. In conclusion, the glucose clamp technique is an invasive procedure that is difficult to use in routine clinical settings. Because the cut-off points to diagnose IR with values derived from ISI-Composite have not been established for pediatric populations, HOMA and QUICKI, despite their lack of precision, remain the most used in clinical practice.