Bone Abstracts

Since 1997, GH therapy has been approved for skeletal disorders including ACH and HCH patients in Japan. The efficacy of GH therapy for short period has been reported in several study. However, few study about efficacy and safety of GH therapy for long term have been shown. The aim of our study is to examine that GH therapy for HCH patients is efficient and safe enough and improve final height and proportion.

18HCH patients (11 males and seven females) who met the criteria for GH treatment initiation were entered in this study. An average age was 5.4 years. Initial height SDS was −3.57±0.51 SDS. Mean GH treatment period was 6.3±2.77 years. Height SDS, IGF1 value, height velocity (HV), upper and lower limb proportion rate, were retrospectively examined on the basis of medical records.

GH treatment itself improved height SDS from −3.57±2.77 SDS to −2.95±0.73 SDS. IGF1 level increased from −0.31±1.2 SDS to +1.02±1.4 SDS after 1 year GH administration and kept above 0 SDS in all patients. As the result, HV remarkably changed from −2.18±1.0 SDS to +2.19±2.6 SDS only 1 year treatment. After puberty, despite of GH treatment, height velocity fell down due to a lack of pubertal growth spurt.

In contrast, the longer GH treatment period showed better responses in an improvement of disproportion. There was no serious adverse effects related to GH treatment so far.

GH therapy for HCH can be effective in not only growth gain but also improvement of disproportion. The treatment effectiveness greatly differed in individuals as the phenotype widely varied. Especially, the period of GH therapy before puberty tends to improve height SDS. Therefore, the earlier GH therapy was introduced, the greater the effect was.

Disclosure: The authors declared no competing interests.