SUN-035 New evidence of growth hormone treatment benefit on bone mineralization during transition from paediatric to adult care in a growth hormone deficient French cohort

Abstract Disclosure: C. Bailly: None. E. Le Roux: None. Introduction: Growth hormone deficiency (GHD) is a rare condition. During childhood (CoGHD), when GHD is confirmed by the hormonal tests, a treatment by growth hormone (GH) is usually introduced. The transition period between paediatric and adult care represents a challenging time. Convincing GHD patients with optimized final stature and their families, to continue GH treatment on such conditions may be complicated. More data need to be collected to better understand the effects of GH treatment during this period, especially for bone health.Objective: The objective of this study is to describe the bone mass density (BMD) and Zscore evolution during transition period in our CoGHD cohort patients, whether they have received GH treatment in adulthood or not.Materiel and methods: We conducted a retrospective study based on our CoGHD patients who had their transition care from 1st January of 1994 to 1st September of 2021. We included all CoGHD patients with a first evaluation (EVAL1) during transition care, and another evaluation (EVAL2) at least 6 months after EVAL1. We described two different populations from our cohort: CoGHD patients continuing GH treatment during more than 6 months between EVAL1 and EVAL 2 (GHT), and CoGHD patients receiving maximum 6 months of GH treatment between the two evaluations (GH0). Results: 162 patients from our 282 CoGHD cohort, were included. In this population, 57 have been treated with GH therapy for 6 months or less (GH0), and 105 continued GH treatment for more than 6 months (GHT). Median follow-up was 5.9 years (3.1-10.8) in GH0 group and 3.6 years (2-6.3) in GHT group.The lumbar spine Z score was -1.61 at EVAL1 and -1.32 at EVAL2 in GH0, and -1.09 at EVAL1 and -0.61 at EVAL2 in GHT (p = 0.047). Lumbar spine BMD was 0.90 g/cm² at EVAL 1 and 0.93 g/cm² at EVAL2 in GH0, and 0.96 g/cm² at EVAL1 and 1.01 g/cm² at EVAL2 in GHT (p = 0.17). The femoral neck Z score was -0.95 at EVAL1 and -0.80 at EVAL 2 in GH0, and -0.87 at EVAL1 and -0.50 at EVAL 2 in GHT (p = 0.16). Femoral Neck BMD was 0.81 g/cm² at EVAL1 and 0.79 g/cm² at EVAL2 in GH0, and 0.89 g/cm² at EVAL1 and 0.85 g/cm² at EVAL2 in GHT (p = 0.76). Conclusion: Our study provides additional evidence supporting the benefit of GH replacement therapy in bone quality in CoGHD during transition care. Presentation: Sunday, July 13, 2025