Preliminary validation of a prediction model for the short-term growth response to growth hormone therapy in children with idiopathic short stature.
A discriminant scoring system, using multivariate analysis, has been developed for pretreatment prediction of responsiveness to a 6-month trial of growth hormone (GH) treatment in short children with subnormal growth velocity, but without GH deficiency. Inclusion criteria included a birth weight above 2.5 kg, height below the 3rd centile for chronological age, height velocity below the 25th centile for bone age, no signs of puberty, a maximal GH response to pharmacological stimulation of above 10 micrograms/l and treatment with GH at a dose of 12-16 IU/m2/week. Children with an increase in height velocity greater than 2.5 cm/year after therapy were considered to be responders. Pretreatment clinical data from 67 patients were employed in a discriminant analysis in order to establish the model. The scoring system developed was as follows: score = -0.4 + 0.92X1 - 0.87X2, where X1 is the height velocity SD score (SDS) for chronological age, and X2 is the bone age SDS for chronological age. This model had a specificity of 96.3% and a sensitivity of 92.5% in predicting the responsiveness to GH. The model has subsequently been applied to a group of 14 patients in order to establish its validity; in this group its sensitivity was 83.3% and its specificity 100%. These preliminary data suggest that the model can be used as a guideline for selecting short, slowly growing, non-GH-deficient children who will respond to short-term GH therapy.
Spagnoli
A
A
Department of Pediatrics, Oregon Health Sciences University, Portland, 97201-3098, USA.
Spadoni
G L
GL
Boscherini
B
B
D001827:Body Height / Q000187:drug effects*; D002648:Child; D005544:Forecasting; D013006:Growth Hormone / Q000627:therapeutic use*; D006801:Humans; D008962:Models, Theoretical; D015999:Multivariate Analysis
D013006:Growth Hormone