Associations between iron status and insulin resistance in Chinese children and adolescents : findings from the China Health and Nutrition Survey / Junxiang Wei, Xiaoqin Luo, Sirui Zhou, Xin He, Jinge Zheng, Xiaomin Sun, Wei Cui

Background and Objectives: Iron homeostasis abnormalities are associated with insulin resistance (IR), but studies on such associations in children and adolescents are limited and have contrasting results. The purpose of this study was to determine the associations between indicators of iron status and IR, and assess if there are sex disparities in these associations. Methods and Study Design: We selected data of 689 children and adolescents (367 boys and 322 girls) aged 6-18 years in the analysis. Serum ferritin, transferrin, and soluble transferrin receptor (sTfR) levels were determined. The level of glycated hemoglobin (HbA1c) was assessed using high performance liquid chromatography. Homeostasis model assessment of insulin resistance (HOMA-IR) was used to indicate the status of insulin resistance. Stepwise and multivariate logistic regression analyses were computed to evaluate associations between iron status and glucose parameters. Results: The prevalence of IR (HOMAIR >3.16) and high HbA1c (HbA1c ≥5.7%) were 29.8% and 16.4%, respectively. Serum transferrin and sTfR were significant associated with HbA1c (p<0.001), while serum transferrin was associated with HOMA-IR (p<0.001). Furthermore, the highest transferring concentrations were associated with higher risks of both HOMAIR and high HbA1c, while decreased sTfR concentrations were associated with a risk of higher HbA1c in both children and adolescents. Conclusions: Serum transferrin and sTfR were statistically significantly associated with glucose parameters, which may suggest that transferrin and sTfR levels should be taken into consideration when studying IR in both boys and girls.

Nutrition.