Comparison of growth hormone therapy response according to the presence of growth hormone deficiency in children born small for gestational age with short stature in Korea: a retrospective cohort study.

Background: This study aimed to compare the response to growth hormone (GH) therapy according to the presence of GH deficiency (GHD) in short-stature children born small for gestational age (SGA) in Korea and to present appropriate GH dose criteria.

Methods: We evaluated 27 children born SGA with short stature and GHD (GHD group) and 23 without GHD (non-GHD group) registered in the LG Growth Study. Growth responses and changes in GH dose over a 2-year GH therapy period were compared, and the factors affecting growth response were investigated.

Results: The standard deviation scores (SDSs) for baseline weight and body mass index (BMI) were significantly lower in boys without GHD than in boys with GHD. The SDS for insulin-like growth factor-1 (IGF-1) was lower among boys without GHD than among boys with GHD, while the SDS for insulin-like growth factor-binding protein-3 (IGFBP-3) was higher among girls without GHD than among girls with GHD; however, there was no significant difference when comparing all children with GHD to those without GHD. Regardless of the presence of GHD, the difference between chronological age and bone age decreased annually. Notably, there was significantly rapid bone age progression among patients without GHD. The findings showed differences in GH dose according to GHD starting from the 2nd year of therapy, with the non-GHD group receiving a significantly higher dose. Regarding the factors affecting growth response, younger age and bone age, higher height SDS, BMI SDS and MPH SDS were related to higher growth response (Δheight SDS and Δgrowth velocity), but there was no statistically significant correlation.

Conclusion: GHD is rare among children born SGA. Nonetheless, if there are any signs of decreased growth velocity or hypopituitarism, the presence of GHD should be assessed before GH therapy, and personalized therapy based on the results is required.