Anthropometric predictors of serum fasting insulin in 9-and 15-year-old children and adolescents

Background and aim: As the prevalence of overweight and obesity increases, the risk of insulin resistance rises. The aim was to study the association between anthropometric measurements and fasting insulin concentration in a population-based sample of 9- and 15-year-old children and adolescents. Methods and results: Subjects were randomly selected 9- and 15-year-old pupils (n = 262) in a cross-sectional, population-based study. Weight and height, waist, hip and mid-arm-circumference and subcutaneous skinfolds were measured using standard procedures. Fasting insulin was measured. In general the mean anthropometric measurements increased across insulin quartiles. Higher fasting insulin concentration was seen in overweight children and adolescents than in those of normal weight (8.3 +/- 4.4 vs. 4.9 +/- 3.6 mmol/L and 11.0 +/- 4.4 vs. 9.0 +/- 4.2 mmol/L in 9- and 15 year-olds, respectively). The odds ratio for having insulin in the highest quartile (age and gender-specific) was, when compared with the lowest quartile, 7.2 (95% CI 3.0-17.2) for body mass index and 6.9 (2.8-16.7) for waist circumference. Other measurements of body fatness were less predictive. About 14-20% of children defined as being of normal weight had high fasting insulin values, i.e., were in the highest quartile of fasting insulin. Conclusions: Body fatness is positively related to fasting insulin concentration in 9- and 15-year-old children. A large number of normal-weight individuals with high fasting insulin concentration was observed, and these children could be at increased risk of weight gain, compared with normal-weight individuals with normal fasting insulin concentration. (c) 2005 Elsevier B.V. All rights reserved.