Birth weight influences long-term catch-up growth and height prognosis of GH-deficient children treated before the age of 2 years

Objective: To investigate which pretreatment variables most significantly a ffect long-term growth response to GH therapy in children with apparently i diopathic GPI deficiency (GHD) treated from a similar and very young age (l ess than 2 years), for the same period (7 years) and with the same therapeu tic protocol. Design and methods: Twelve children with either isolated GHD or multiple pi tuitary hormone deficiency were treated with biosynthetic human GN (0.7 IU/ kg per week) and were examined every 6 months. Height measurements were per formed by Harpenden stadiometers, Bone age was evaluated every 12 months. Results: The onset of therapy was followed in all patients by an important height gain, which attained its zenith during the first year of treatment a nd became progressively less evident during the next 4 years. Cumulative he ight gain was 3.0 +/- 1.7 SDS. Thanks to the therapy, at the end of the 7-y ear treatment period, average height in the entire series was not significa ntly far from mean target height (TH) (-0.7 +/- 1.3 vs -0.3 +/- 0.4 SDS) an d average predicted height (PH) (-0.2 +/- 1.4 SDS) was very close to TK. A stepwise regression analysis showed that both catch-up growth under therapy and PH at the end of the 7-year treatment period were positively influence d by birth weight (BW). Conclusions: a) Our 7-year prospective study on GHD infants treated with GI -I from less than 2 years of age confirmed the importance of early diagnosi s and treatment of GHD in childhood, b) The influence of BW on growth respo nse to GH therapy in GHD children persists over time, at least when treatme nt is begun from less than 2 years of age.