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The extent to which childhood GHD affects adult fracture risk is unclear. We measured femoral strength in adult transgenic growth‐retarded rats as a model of GHD. Long‐term, moderate GHD was accompanied by endocrine and morphometric changes consistent with a significant reduction in femoral strength.Introduction:Childhood growth hormone deficiency (GHD) is associated with osteopenia, but little is known about its effects on subsequent adult bone strength and fracture risk.Materials and Methods:We have therefore measured femoral strength (failure load measured by three‐point bending) in a new model of moderate GHD, the transgenic growth‐retarded (Tgr) rat at 15, 22–23, and 52 weeks of age, and have quantified potential morphological and endocrine determinants of bone strength.Results:Skeletal growth retardation in Tgr rats was accompanied by a sustained reduction in the anterior‐posterior diameter of the femoral cortex, whereas mid‐diaphyseal cortical wall thicknesses were largely unaltered. Total femoral strength was significantly impaired in Tgr rats (p< 0.01), and this impairment was more pronounced in males than females. Compromised bone strength in Tgr rats could not be accounted for by the reduction in mechanical load (body weight) and was not caused by impairment of the material properties of the calcified tissue (ultimate tensile stress), despite marked reductions in femoral mineral density (areal bone mineral density; p< 0.001). Microcomputerized tomographical analysis revealed significant modification of the architecture of trabecular bone in Tgr rats, with reductions in the number and thickness of trabeculae (p< 0.05) and in the degree of anisotropy (p< 0.01). The marked reduction in plasma insulin‐like growth factor‐1 in Tgr rats was accompanied by the development of high circulating leptin levels (p< 0.01).Conclusion:These results show that the changes in endocrinology and bone morphology associated with long‐term moderate GHD in Tgr rats are accompanied by changes consistent with a significant reduction in the threshold for femoral fracture.

The extent to which childhood GHD affects adult fracture risk is unclear. We measured femoral strength in adult transgenic growth‐retarded rats as a model of GHD. Long‐term, moderate GHD was accompanied by endocrine and morphometric changes consistent with a significant reduction in femoral strength.

Dual‐energy X‐ray absorptiometry (DEXA) is a rapid and precise technique for the assessment of bone mineralization in children. Interpretation of the results in growing children is complex as results are influenced by age, body size (height and weight) and puberty. Conventionally, bone mineral data derived from DEXA have been presented as an areal density [BMD; bone mineral content (BMC, g)/projected bone area (BA, cm2)], yet this fails to account for changes in BMC that result from changes in age, body size or pubertal development. Measurement of BMC and BA of the whole body, lumbar spine and left hip were made in 58 healthy boys and girls using DEXA. The relationship between BMC and BA was curvilinear, with the best fit being that of a power model (BMD =BMC/BAλ, where λ is the exponent to which BA is raised in order to remove its influence on BMC). The value of λ changed when measures of body size and puberty were taken into account (e.g. for lumbar spine from 1.66 to 1.49). Predictive formulae for BMC were produced using regression analysis and based on the variables of age, body size and pubertal development. This provides a method for interpreting the measured BMC which is independent of such variables and a constant reference range for children aged 6–18 y.

Clinical symptoms of diabetes-related complications are very rare in children and adolescents with type 1 diabetes (T1D). Screening for complications aims to detect their presence shortly after development but before they cause clinically significant symptoms. Early detection of complications, alongside efforts to improve glycaemic control, can slow the progression of microvascular complications with consequently improved quality of life and life expectancy. An ideal screening programme should be evidence based and should include the majority of clinically important complications and associated diseases. Such programmes have been formulated by multidisciplinary bodies representing a number of specialist diabetes societies worldwide.