Levels of the small insulin-like growth factor-binding protein are strongly related to those of insulin in prepubertal and pubertal children but only weakly so after puberty

Publisher Website
Google Scholar
Abstract
We have looked at the relationship between fasting levels of insulin and a small insulin-like growth factor (IGF)-binding protein (IBP-1) in a cross-sectional study of 116 normal subjects aged 5–48 years. The relationship between IBP-1 and insulin was also examined within individual normal children in over-night profiles of IBP-1 and insulin obtained from two children at each stage of puberty (Tanner stages 1–5). In the cross-sectional study high levels of IBP-1 were found in early childhood and these fell throughout puberty as fasting levels of insulin rose. Multiple regression analysis revealed that both these changes were predominantly due to pubertal development rather than to age. After the age of 16 IBP-1 levels remained low despite fasting insulin levels returning to prepubertal levels. A strong negative correlation was obtained between IBP-1 and insulin in children of 5–16 years (r = −0·63; n = 60; P r = −0·69; n = 53; P Journal of Endocrinology (1989) 121, 383–387