ESPE Abstracts

Prediction of growth hormone (GH) therapy effectiveness in children with short stature is an important issue for optimizing its course. Recently, our research group has published prediction models derived with neural networks. The main predictors of final height (FH) in our model were: patient’s height SDS at therapy onset, pre-treatment change of height SDS (HSDS V₀) and pre-treatment IGF-I and IGFBP-3 secretion but not the results of GH stimulation tests; the increases of IGF-I and IGFBP-3 concentrations in 1^st year GH therapy were also significant variables. The aim of present study is to analyze the influence of IGF-I and IGFBP-3 secretion before and during GH therapy on FH in children with wide range of GH secretion. Analysis comprised 133 children (89 boys) with short stature (GH deficiency or idiopathic short stature), treated with GH up to FH. In all children 20 auxological and hormonal parameters was assessed before treatment, in 1^st year of therapy and at FH (for details see: Smyczynska U et al. doi.org/10.1530/EC-17-0277). According to their FH, the patients were classified into 3 groups: below 3 centile (<3c), between 3 and 10 centile (3-10c) and over 10 centile (>10c). In all the patients concentrations of IGF-I and IGFBP-3 were measured before treatment and in 1^st year of therapy. The index of difference between IGF-I SDS increase and IGFBP-3 SDS increase in 1^st year of treatment (DIGF difference) was calculated. At therapy onset IGF-I SDS was higher in <3c group (−1.55±1.07) and 3-10c group (−1.60±1.10) than in >10c group (−2.10±1.09), while IGFBP-3 SDS was lower in <3c group (−0.67±0.72) than in groups 3-10c (−0.37±0.96) and >10c (−0.40±1.04). In 1^st year of treatment there were no significant difference in both IGF-I SDS and IGFBP-3 SDS between all the groups. The increase of IGF-I SDS was significantly (P<0.05) higher in group >10c (2.72±0.94) than in groups <3c (2.18±0.97) and 3-10c (2.13±0.92), similarly ΔIGF difference was significantly higher in >10c (1.87±1.18) than in both <3c (1.15±0.63) and 3-10c (1.27±0.82). Pre-treatment IGF-I and IGFBP-3 secretion and their increase during the initial phase of GH therapy are important predictors of the attained FH. Neural models are useful for the identification of variables that should be subjected to further analysis.