Response to rhGH therapy in short children born at very low birth weight.

Introduction: Although the clinical benefits of long-term rhGH therapy have been well demonstrated in children born small for gestational age (SGA), little is known about the outcomes of this therapy in children born with very low birth weight (VLBW). This study aimed to report the short and long-term response to rhGH therapy in a cohort of VLBW patients, comparing subgroups according to size, gestational age, and causal factors associated with VLBW.

Methods: We describe 33 patients born at VLBW treated with rhGH; 16 also received GnRHa. Medical records were analyzed at baseline and after one year of rhGH treatment. Data on the adult height SDS from 23 patients were also collected. Growth velocities and height SDS changes were calculated, along with the differences between the observed and predicted growth velocities.

Results: The first-year growth velocity (7.5±2.1cm/y) was aligned with prediction models for SGA children. After one year of rhGH treatment, height SDS improved from -3.0±1.1 to -2.6±1.3, with no differences among subgroups. Among patients reaching adult height, 73.9% remained short (-2.5±1.3) after long-term therapy (6.7±3.3y). The initial height SDS, height SDS change in the first year of treatment, and target height SDS were key independent predictors of height gain.

Conclusion: The response to rhGH treatment was suboptimal in the VLBW group, independent of the size, gestational age, or etiological diagnosis. However, adult height may be improved in patients receiving rhGH treatment. This underscores the need for tailored protocols and further investigations to optimize outcomes in this population.