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Context: Increased fat mass has been reported in children and adults born small for gestational age (SGA). However, the progression of anthropometric parameters have been poorly documented in SGA adults., Objective: We hypothesized that SGA individuals would remain susceptible to gain more fat when adults beyond the period of postnatal catch-up growth., Study Population and Design: From a community-based cohort, 389 subjects born full-term SGA (body weight < 10th percentile) were compared with 462 subjects born appropriate for gestational age (25th < body weight < 75th percentile). Anthropometric parameters were measured at 22 and 30 yr as well as body composition (by multifrequency bioelectrical impedancometry and skinfold thickness) at 30 yr., Results: Both groups gained weight, body mass index (BMI), and waist circumference. Progression of BMI was significantly greater in SGA (1.8 +/- 2.6 vs. 1.4 +/- 2.6 kg/m(2); P = 0.03). At 30 yr, the proportion of obese individuals was significantly increased in SGA (12.1 vs. 6.5%; P = 0.02), and percent body fat was significantly higher (23.5 +/- 8.7 vs. 21.9 +/- 8.0%; P = 0.01), the observation of which was confirmed by skinfold measures. Similarly, waist circumference gain was significantly greater in SGA (6.4 +/- 7.6 vs. 5.5 +/- 7.9, P = 0.04 when adjusted for gender and age)., Conclusion: Over 8-yr follow-up, adults born SGA gained more BMI than appropriate for gestational age, resulting in greater fat mass with more abdominal fat. These data suggest that the consequences of fetal growth restriction on body composition are evolving beyond the period of early postnatal catch-up.

Context: There is evidence to suggest that IGF-I plays a role in regulating bone turnover., Objective: To evaluate the relationships between serum concentrations of IGF-I and IGF-binding protein-3 (IGFBP-3), and bone metabolism markers in healthy children., Design and Setting: Prospective cross-sectional study., Subjects and Methods: A cohort of 579 boys and 540 girls, all healthy Caucasian, were included in this study. Serum IGF-I and IGFBP-3 concentrations, bone alkaline phosphatase (BAP) and CrossLaps (markers of bone formation and bone resorption respectively) levels were evaluated as a function of age, gender, pubertal stage and body mass index., Results: Serum IGF-I SDS levels were positively correlated with BAP and CrossLaps SDS levels before and after puberty, and also with CrossLaps during puberty (weak correlation). Serum IGFBP-3 SDS levels were positively correlated with BAP and CrossLaps levels before, during (weak correlation) and after puberty (for BAP levels only)., Conclusions: This study demonstrated the independent association between serum IGF-I and IGFBP-3 concentrations with both serum bone formation and resorption markers in healthy children. Physiological differences before, during and after puberty in the association of serum IGF-I and IGFBP-3 levels with the serum bone metabolism markers were found. These differences may be related to differences in interactions between sex steroid hormones and the GH/IGF-I system, bone metabolism and growth during the pubertal transition. Improvements in our understanding of life course determinants of the IGF-I system and bone metabolism are required to shed further light on the role of the GH/IGF-I axis in bone remodelling.

Context: The unexpected observation of a normal GH peak in 22% of young adults with childhood-onset GH deficiency (GHD) and ectopic neurohypophysis has raised questions about the criteria defining GHD in young adults and whether patients with subsequent increases in GH secretion nonetheless have a subtle form of GHD., Objective: Our objective was to determine the characteristics of patients with childhood-onset nonacquired GHD who recover normal peak GH secretion when adult height has been achieved., Design and Setting: We conducted a university hospital-based observational follow-up study., Participants: Sixty-two patients with ectopic neurohypophysis (n = 24), isolated hypoplastic anterior pituitary (n = 14), or normal hypothalamic pituitary area (n = 24) on magnetic resonance imaging (MRI) at the time of GHD diagnosis underwent reevaluation of the GH-IGF-I axis at a mean age of 16.8 +/- 1.6 yr., Main Outcome Measures: Outcome measures included clinical and MRI findings and serum IGF-I and peak GH levels., Results: On retesting, peak GH exceeded 10 microg/liter in 31 patients (50%): six (20%) patients with ectopic neurohypophysis, 10 (32%) patients with initially isolated hypoplastic anterior pituitary, and 15 (48%) patients with normal MRI findings. Among these patients, serum IGF-I levels were significantly lower in patients with ectopic neurohypophysis than in those without structural abnormalities of the hypothalamic pituitary axis (n = 25), but patients without structural abnormalities also had significantly lower serum IGF-I levels than control subjects, after controlling for age, sex, and body mass index (mean serum IGF-I levels of 374 +/- 83 vs. 446 +/- 108 microg/liter; beta-coefficient = -72; P = 0.003)., Conclusions: The severity of the disease seems to have decreased over time in these patients, who may nonetheless present persistent pituitary failure. The natural history and clinical implications of these findings remain to be clarified. The possibility of a deterioration in the secretion of GH and other pituitary hormones later in life in a subset of these patients warrants the careful long-term follow-up of this population.