Childhood wrist circumference is not a predictor of insulin resistance in adulthood

The gold standard measurement of insulin resistance (IR), the euglycemic, hyperinsulinemic clamp (ie, IR adjusted for lean body mass [M_lbm]: insulinstimulated glucose uptake = insulin sensitivity/resistance),^1,2 is technically challenging, invasive, and expensive, limiting its clinical usefulness. Surrogate measures of IR, including fasting insulin and the homeostasis model assessment of IR (HOMA-IR),³ require a blood sample, show only moderate correlation with direct measures of IR in children,² and vary greatly among laboratories.⁴ A noninvasive screening tool easy to perform in the office that provides an acceptable estimate of IR risk is needed. It has been proposed that wrist circumference (WrC) may be a good surrogate in children as a simple, noninvasive marker of IR.⁵ A close cross-sectional relationship between pediatric WrC and HOMA-IR has been reported in overweight youth5 and supported by recent findings that wrist breadth was associated with HOMA-IR in normal-weight children.⁶ We hypothesized that childhood WrC would positively predict adult IR as measured by euglycemic hyperinsulinemic clamp. We also assessed HOMA-IR to provide a direct comparison to the previous cross-sectional studies.