Endocrine Abstracts

Background: Childhood-onset GH deficiency (CO-GHD) is perceived to be a cause of low bone density and osteoporosis in adulthood. Data on bone mass and body composition of GH-treated adolescents with CO-GHD at final height are inconsistent.

Aims: To compare size/height corrected parameters of bone mass and body composition in adolescents with CO-GHD at final height.

Method: Review of CO-GHD treated patients at final height between 2005 and 2012 in a single tertiary paediatric centre. BMD-Z-scores of patients were compared to height-matched local healthy controls. Percent predicted bone area for age (ppBAforAge), percent predicted bone mineral content for bone area (ppBMCforBA), and bone mineral apparent density (BMAD) was calculated to reflect body size and degree of mineralisation respectively.

Results: Lumbar spine (LS) and total body (TB) DXA scan results of CO-GHD at final height (n=23, seven with isolated GHD) median age 17.8 years (15.5–20.5, 12 males) were compared to controls (n=23) median age 16.8 years (14.7–19, 12 males). Median uncorrected BMD-Z-scores in GHD were lower at TB (−1.4 (−3.2–1.2) and LS (−2.1 (−4.2–1.1)) compared to TB (0.2 (−0.9–2.3)) and LS (−0.1 (−1.6–2.8)) in the controls (P<0.001). Size corrected analysis showed male adolescents with GHD, unlike females, have lower TB (ppBA for Age) (81%(68–97)) and (ppBMC for BA) (95%(91–108)), and lower LS (ppBMC for BA) (91.5% (80–120)) and BMAD (g/cm³) (0.15 (0.13–0.20)) compared to controls males TB (ppBA for Age) (106%(87–118)), TB (ppBMC for BA) (109%(97–117)) and LS (pp BMC for BA) (106%(100–124)) and BMAD (0.17 (0.16, 0.20)), P<0.05. Males with GHD also have increased fat-mass (FM)(kg) (16.2 (4.5–70.7) in GHD: 7.7 (5.6–32.5) in controls, P=0.03) and decreased lean mass (LM)(kg) (47.1 (26.8–62.3) in GHD: 57.9 (49.1–61.2) in controls, P<0.001), whereas females with GHD have a higher FM compared to matched females (22.4 (11–44.9) vs 19.1 (8.8–48.10), (P=0.04)) with no difference in LM (12.7 (9.4–15.6) vs 13.8 (4.9–17.3), P=0.8) respectively.

Conclusion: Male adolescents with CO-GHD appear to have reduced mineralisation, together with narrower bones, and alteration in body composition when compared to controls.