Wrist breadth and homeostasis model assessment of insulin resistance in youth: The fels longitudinal study

Objectives: There is biological crosstalk between insulin signaling and bone remodeling pathways, and wrist circumference and bone area were recently found to associate with insulin resistance independent of body mass index (BMI) in overweight/obese children. We aimed to expand on this work by using more specific measures of adiposity for adjustment and examining children with broader range of BMI. Methods: We used serial data (1,051 total measures) on 313 non-Hispanic white youth (ages 8-18 y) from the Fels Longitudinal Study with homeostasis model assessment of insulin resistance (HOMA-IR) as the outcome. Internal standard deviation score (SDS) for wrist breadth was evaluated as a predictor of HOMA-IR (log-transformed) before and after adjusting for internal-sample SDSs for BMI, waist circumference (WC), and total body fat (TBF) from dual energy X-ray absorptiometry, in addition to age, sex, Tanner stage, and birth year, using generalized estimating equations. Results: Before additional adiposity adjustment, we found a significant positive association between wrist breadth SDS and log-transformed HOMA-IR (β = 0.13; 95%CI: 0.09-0.17), which remained significant after adjusting for TBF SDS (β = 0.09; 95%CI: 0.05-0.13; P < 0.001), BMI SDS (β = 0.06; 95%CI: 0.02-0.10; P = 0.007), and WC SDS (β = 0.06; 95%CI: 0.02-0.09; P = 0.005). Conclusions: Further work is needed to determine whether simple frame size measures such as wrist breadth may be useful markers of metabolic risk.