ESPE Abstracts

Background: Women with Turner syndrome (TS) are known to be at risk of osteoporosis and fracture. While childhood GH treatment is common in TS, the impact of this therapy on bone health has been poorly understood.

Objective: The purpose of this study was to determine the effect of childhood GH-treatment on adult bone quality in TS women using dual X-ray absorptiometry (DXA) and high resolution peripheral quantitative computed tomography (HR-pQCT).

Methods: TS subjects aged 16–45 years were included. DXA of lumbar spine, hip, and radius and HR-pQCT scans of the radius and tibia were completed. HR-pQCT micro-architecture analysis included total volumetric BMD, cortical BMD, trabecular BMD, and total area. Finite element (FE) analysis and polar moment of inertia (pMOI) were used to estimate bone strength. Group means were compared using independent t-tests.

Results: Twenty-eight TS subjects were recruited (GH-treated=12 and non-GH-treated=16). Both groups were similar in regards to age and bone health related lifestyle parameters. GH-treated subjects were 7.4 cm taller than non-GH-treated subjects (95% CI 2.5–12.3 cm, P=0.005). DXA determined areal BMD of hip, spine, and radius was similar between treatment groups. At the radius and tibia total bone area was greater among GH-treated subjects (+20.4 and +21.2% respectively, P<0.05) while other micro-architectural results were not different between groups. FE determined bone strength trended higher in the GH-treated group (radius, +12.3%; P=0.28 and tibia, +8.1%; P=0.25), but results were not statistically significant. pMOI was significantly greater among GH treated subjects (radius, +35.0%; tibia, +34.0%; P<0.05).

Conclusions: Childhood GH-treatment in TS was associated with an increased height, larger bones and greater pMOI, while no significant difference in DXA derived BMD, HR-pQCT micro-architectural parameters, or FE estimated bone strength were detected. This increase in bone size may confer benefit for fracture reduction in these GH-treated patients.