Clinical Predictors of Good/Poor Response to Growth Hormone Treatment in Children with Idiopathic Short Stature.

INTRODUCTION

Children with idiopathic short stature (ISS) are known to have varying responses to growth hormone (GH) treatment (GHT).

METHODS

We conducted a post hoc analysis to identify clinical characteristics predictive of good and poor response during year 1 of GHT. Data from the NordiNet® IOS (NCT00960128) and the ANSWER Program (NCT01009905) were used. Patients were grouped according to their response to GHT; good, middle, and poor responders had a change in HSDS of >1.0, 0.4-1.0, and <0.4, respectively. Patients were also grouped according to their responsiveness to GH dose. Logistic regression modelling was performed to identify clinical characteristics predictive of response to GHT.

RESULTS

The response analysis set included 207 patients. Patients were 3-11 years old (males) or 3-10 years old (females) at the start of treatment and were prepubertal throughout year 1 of treatment. Age at the start of treatment (odds ratio [OR] 0.69, 95% confidence interval [CI] 0.5; 0.9, p = 0.0169) and distance from target HSDS (OR: 2.05, 95% CI: 1.1; 3.9, p = 0.0259) were found to be significant independent predictors of being in the good- versus poor-response groups. When patients were grouped according to their responsiveness to GH dose, a positive correlation between GH dose and change in HSDS was observed.

CONCLUSION

We identified younger age and further distance from target HSDS as clinical predictors of response to GHT in a heterogenous population of children with ISS. Future studies, designed to identify the genetic determinants of response to GHT, could further facilitate individualisation of GHT.