ESPE Abstracts

Short stature is one of the most common concerns presented to pediatric endocrinologists. ISS describes a heterogeneous group of children with a height of more than 2 SD score (SDS) below the corresponding mean height for a given age, sex, and population group without underlying aetiology. The primary objectives of GH treatment are acceleration of growth velocity to promote normalization of stature during childhood and attainment of normal FAH.

Objectives: Assess and compare GH treatment response for ISS and GHD groups: measured as height gain at 1st and 3rd year, and FAH SDS. Also, investigate potential predictors for better outcomes of GH therapy.

Methods: A cross-sectional retrospective review of children with short stature treated with rGH at a pediatric endocrine clinic under the indications of ISS and GHD; followed during the period from Jan 2011 and Dec 2022.

Results: A total of 225 were enrolled, 63.1% (n=142) with ISS and 36.9% (n=83) with GHD, of which 69.3% were male. At rGH therapy initiation, the mean age was 11 years (± 2.7) compared to GHD 10 years (± 3.6) with height SDS of -2.5 (± 0.47) in comparison to -2.7 (± 0.6 SD) for GHD subjects (P-value < 0.06). Treatment outcomes at 1 & 3 years, mean height SDS gain for the ISS group was 0.6 (± 0.3) and 1.14 ± (0.46) compared to GHD of 0.77 (±0.6) and 1.5 (± 0.7); respectively (p -value= 0.0004). Adult height SDS was recorded for 96 subjects (42.6%), with better outcomes for GHD -1.15 (±0.65) than ISS -1.3 (±0.6). The majority (90%) of subjects under GHD and ISS achieved AH SDS above -2 SD. Multivariate regression analysis revealed age at GH therapy initiation and height SDS at baseline were inversely correlated with height gain at 1 year, 3rd year and final AH (P < 0.05).

Conclusions: At 1-year and 3-year follow-ups, both had significant increments in height SDS on average. Almost a third of our cohort reached FAH during the study period, and both subgroups attained normal FAH (HSDS>-2). This is consistent with the results of previous observational studies, showing that children with GHD reach a mean height SDS of approximately −1.0, and children with ISS reach a mean height SDS of approximately −1.4. Earlier recognition and referral for short stature, and efforts to start GH treatment at a younger age, would most likely have resulted in greater gains in height and an increase in adult HSDS.