Update on pubertal development in France. PROSPEL - Observational study. Preliminary feasibility study.

INTRODUCTION: Recent publications report a decrease in the age of onset of pubertal changes in the United States and Europe. The PROSPEL study (PRemier Observatoire des Stades Pubertaire en Libéral) will provide the first French data on the age at which pubertal signs appear. Before considering this work at the national level, we wanted to assess its feasibility. MATERIALS AND METHODS: Private pediatricians and general practitioners were recruited in Bordeaux and Toulouse. Before participating in the study, they had been trained in pubertal assessment and then evaluated. Each physician completed 1-4 weeks of inclusion during which children aged 5-18 years seen in consultation were included, except children who were adopted or had a chronic condition. Pubertal stages were assessed according to Tanner's classification and using an orchidometer for testicular volume. The causes of non-realization were documented where appropriate. Inter-individual reproducibility was analyzed by a double examination for a number of children who had previously given their consent. RESULTS: In total, 63 physicians participated in the study (35 pediatricians and 28 general practitioners). All were certified at the end of the training session. A total of 2646 children were included (1318 girls, 1328 boys) with a homogeneous age distribution. The study was carried out in 83.5% of cases. The main reason for non-realization was that physicians did not propose the study to patients who met the criteria (10.1%). Lack of time was the main reason. Inter-individual reproducibility was excellent. DISCUSSION AND CONCLUSION: Our results attest to the good feasibility of the PROSPEL study. They allowed us to validate our methodology, the training and certification of the participating physicians, and to consider extending the study to the national level.

Evolution of IGF-1 in children born small for gestational age and with growth retardation, treated by growth hormone adapted to IGF-1 levels after 1 year.

AIM: This study was designed to estimate the percentage of growth hormone (GH)-treated children born small for gestational age (SGA), with serum IGF-1 >2 SDS before and after GH dose adaptation. METHODS: SGA boys aged 4-9 and girls aged 4-7 with a height <-2 SDS and an annual growth rate below the mean received a subcutaneous GH dose of 57 µg/kg/day for 2 years. The GH dose was to be decreased by 30% in children with serum IGF-1 >2 SDS at 12 months and on the previous sample. The GH dose could be reduced a second time to 35 µg/kg·day. IGF-1 and IGFBP-3 dosages were centralized. RESULTS: Among the 49 (21 boys) children included in the study, 8 (16.3%) had an IGF-1 >2 SDS consecutively at 9 and 12 months (95% CI 7.3, 29.7). The GH dose was decreased in 6/8 children. However, IGF-1 levels were elevated at several nonconsecutive determinations in 45% (95% CI 28.4, 56.6) of the patients. CONCLUSION: A high IGF-1 level is observed in 45% of the GH SGA-treated children with a relatively high dose of GH. A 30% reduction in the GH dose causes a decrease in IGF-1 below 2 SDS in most children.