All issues > Volume 41(1); 1998

Original Article

J Korean Pediatr Soc. 1998;41(1):90-98. Published online January 15, 1998.

The Relationships of Pretreatment IGF-I SDS, Delay in Bone Age and Response to Recombinant Human Growth Hormone(rhGH) Therapy in Children with Growth Hormone Deficiency

Seon-Young SY You¹, Ki-Joong KJ Kim¹, Jeh-Hoon JH Shin¹, Jin-Nyoung JN Park¹, Hee-Jeong HJ Ahn¹, Yong-Joo YJ Kim¹

¹Department of Pediatrics, College of Medicine, Hanyang University, Seoul, Korea

Correspondence Jeh-Hoon JH Shin ,Email: 1

Abstract

Purpose
: To assess whether pretreatment IGF-I SDS and pretreatmental bone age are useful indicators in the response of rhGH therapy in children with GH deficiency(GHD), the relationship between pretreatment IGF-I SDS, delay in bone age and the growth response during the first year of rhGH treatment was analyzed.
Methods
: This study included 12 children with GHD. We measured IGF-I levels by RIA after acid-ethanol extraction at pretreatment and then calculated IGF-I SDS as follow : SDS =(IGF-Imean IGF-I for normal subjects of the same age and sex)/SD of IGF-I for normal subjects of the same age and sex. GH levels were measured by immunoradiometric assay. All patients were treated with rhGH, 0.1IU/kg daily, 6 times a week for 1 year.
Results
: Twelve patients (6 males and 6 females), age distribution from 4 to 16 years, were studed. The data is reported as the mean±SD. Height SDS for chronologic age of the group as a whole as -3.6±1.0 and bone age was 8.2±3.4 years. Pretreatment height velocity (HV) was 4.0±1.7cm/yr and the HV during each 3 months of therapy were 10.1±4.5cm/yr, 9.6±4.5cm/yr, 8.5±4.3cm/yr and 7.8±1.3cm/yr, respectively and therefore the HV during the first year of rhGH therapy increased to 9.3±2.9cm/yr (P =0.002). Pretreatmental IGF-I SDS was -2.2±0.9 (-0.4～-3.6). A significant negative correlation between pretreatmental IGF-I SDS and incremental height gain was obtained (r=-0.40, P < 0.05). The height velocity of the group whose pretreatmental IGF-I SDS was below -2 (n=8) as a whole increased significantly from 3.5±1.8cm/yr to 10.3±2.9cm/yr (P =0.001). Pretreatmental bone age delay was 3.1±1.9(0.5-7.8) years. The height velocity of the group whose pretreatmental bone age delay above 2 years(n=9) increased significantly from 4.1±1.1cm/yr to 9.7±2.9cm/yr (P =0.001). Conclusion : The height velocity of GH deficient children whose pretreatmental IGF-I SDS below -2 or pretreatmental bone age delay above 2 years increased significantly after rhGH therapy. It suggests that the pretreatmental IGF-I SDS and pretreatmental bone age may be significant indicatiors in the response of GH therapy in children with GHD.

Keywords :Growth hormone deficiency, IGF-I, Bone age, Prediction, Growth hormone therapy