Prediction of adult height in healthy Japanese children

Puberty and pubertal growth in healthy Turkish girls: no evidence for secular trend

BACKGROUND

Assessment of pubertal stages should be related to updated and reliable referance data from the same background population.

OBJECTIVE

The aim of this study was to provide normative data for the onset and tempo of puberty in Turkish girls and analyze the growth parameters in puberty.

METHODS

The analyses are based on data that were collected and evaluated biannually on 1020 Turkish school children aged 8-18 years and a subsample of 101 girls who had reached final height (FH). The data were analyzed cross-sectionally in the total group and longitudinally in the subsample.

RESULTS

Mean age and height (Ht) at onset of puberty were 10.1 ± 1.0 years and 141.7 ± 7.6 cm, respectively. Peak height velocity (HtV) was 8.5 ± 1.0 cm/year. Total pubertal height gain was 16.0 ± 3.9 cm. The duration of puberty was 4.9 ± 1.2 years. Age at menarche was 12.2 ± 0.9 years. Height at onset of puberty was positively correlated with FH (p < 0.0001). Body size (weight and height) at onset of puberty and weight and height velocity before the year of onset of puberty correlated negatively with age at onset of puberty (p < 0.05).

CONCLUSION

In conclusion, these results provide normative data for pubertal stages and growth parameters in girls in puberty. Height at onset of puberty is the most important determinant of FH. There is no secular trend for the onset of puberty. Weight does seem to affect the onset of puberty but not FH.

Analysis of puberty and pubertal growth in healthy boys

The aim of this study was to provide normative data for the onset and tempo of puberty in healthy boys. The analyses are based on data that were collected and evaluated biannually on 1112 Turkish school children aged from 8 to 18 years and a subsample of 30 boys who had reached final height (FH). The data were analyzed cross-sectionally in the total group and longitudinally in the subsample. Mean age and height (Ht) at onset of puberty were 11.6 +/- 1.2 years and 146.1 +/- 7.7 cm, respectively. Peak height velocity (HtV) was 10.1 +/- 1.6 cm. Total pubertal height gain was 26.4 +/- 4.3 cm. The duration of puberty was 4.9 +/- 0.6 years. Height at onset of puberty was positively correlated with FH (p < 0.0001) and with duration of puberty (p = 0.03). Body mass index at onset of puberty correlated negatively with age at onset of puberty (p < 0.009) and with the duration of puberty (p = 0.05) but not with FH. In conclusion, these results provide normative data for Ht and HtV for each testicular volume stage for boys in puberty. Height at onset of puberty is the most important determinant of FH. There is no secular trend for the onset of puberty. Weight does seem to affect the onset and tempo of puberty but not FH.

Growth hormone therapy

Growth hormone (GH) therapy has revolutionized treatment of children with growth hormone deficiency (GHD). Improved height outcome with final height in the target height range has been achieved in these children. Identification of Creutzfeldt-Jakob disease, a deadly prion mediated disorder, in recipients of pituitary GH accelerated the transition from pituitary derived GH to recombinant GH. Once daily subcutaneous administration of the freeze-dried preparation at evening is the recommended mode of GH therapy. Studies have led to use of higher dose of GH for improving height outcome (0.33 mg/kg/week or 0.14 IU/kg/day) albeit at a significantly high cost. Growth velocity increases from 3-4 cm/year before therapy to 10-12 cm/year during the first two years of therapy and is maintained at 7-8 cm/year after a period of two years. Close follow-up with regular clinical and laboratory monitoring is essential for achieving a desirable height outcome. A theoretical unlimited supply has led to wide spread use of GH in a variety of disorders other than GHD. Initially started in children with Turner syndrome, GH has now been used in chronic renal failure, idiopathic short stature and intrauterine growth restriction besides a wide array of newly emerging indications.

Efficacy and Safety of Long-Term Continuous Growth Hormone Treatment of Children Born Small for Gestational Age

Twelve years of growth hormone (GH) therapy of short children born small for gestational age (SGA) have demonstrated that GH is an effective and well-tolerated therapy. Most children will reach a normal adult height (AH). AH of 55 SGA adolescents was comparable for those treated with a GH dose of 1 or 2 mg/m2 (approximately 0.033 or 0.066 mg/kg) per day, mean (SD) AH SDS being -1.2 (0.7) and -0.8 (0.7), respectively. GH therapy had no influence on the age at onset, the progression of puberty, duration of puberty and pubertal height gain. GH therapy induced higher fasting and glucose-stimulated insulin levels after 1 and 6 years, but 6 months after GH stop, all levels returned to normal. At baseline mean systolic blood pressure was significantly increased, but both systolic and diastolic blood pressure decreased significantly during 6 years of GH and remained so after GH stop. GH therapy demonstrated a beneficial effect on serum lipid profiles, body composition, bone mineral density and head growth. Treatment with 2 mg GH/m2 per day induced mean serum IGF-I levels of +2 SDS, whereas IGF-I levels remained within the normal range with 1 mg GH/m2 per day. In conclusion, long-term GH therapy of short SGA children with 1 mg/m2 per day appears to be effective and safe. Since the future consequences of high serum IGF-I levels during long-term GH therapy with 2 mg/m2 per day are as yet unknown, it seems safer to treat short prepubertal SGA children with a GH dose of 1 mg/m2 per day when children are to be treated continuously for many years.

Puberty in growth hormone-treated children born small for gestational age (SGA)

Seventy-five small for gestational age (SGA) children were studied in a randomized, double-blind, dose-response GH trial with either 1 or 2 mg GH/m(2).d. Mean (SD) age at the start of GH therapy was 7.3 (2.2) yr. Data were compared with Dutch reference data. In SGA boys, mean (SD) age at onset of puberty was 12.0 (1.0) and 11.6 (0.7) yr, and in SGA girls it was 10.9 (1.1) and 10.6 (1.2) yr when treated with 1 and 2 mg GH/m(2).d, respectively. SGA boys treated with the lower GH dose started puberty later than the appropriate for gestational age (AGA) controls; for the other GH-dosage groups there was no significant difference in age at onset of puberty compared to AGA controls. The age at menarche and the interval between breast stage M2 and menarche were not significantly different for GH-treated SGA girls compared to their peers. The duration of puberty and pubertal height gain of GH-treated SGA boys and girls were not significantly different between the two GH-dosage groups and were comparable with untreated short children born SGA. In conclusion, long-term GH therapy in short SGA children has no influence on the age at onset and progression of puberty compared to AGA controls, regardless of treatment with a dose of 1 or 2 mg GH/m(2).d. Duration of puberty and pubertal height gain were not significantly different between the GH-dosage groups.

Análise crítica da previsão da altura final

A preocupação dos pais com relação à altura final dos filhos coloca o médico na difícil situação de ter que oferecer um número, tirado de fórmulas, que dá resultados nem sempre precisos. Os métodos de avaliação da altura final são falhos e baseiam-se em parâmetros de difícil quantificação como, por exemplo, a idade óssea. Por outro lado, a avaliação de várias modalidades terapêuticas baseia-se na modificação da previsão da estatura final para mais, efeito benéfico do tratamento, o que pode acarretar alguns equívocos no que tange à análise da terapêutica em questão. Mesmo em situações em que se estabelece claramente a necessidade de reposição hormonal, como avaliar o impacto desta terapêutica na altura final? É feita uma análise dos métodos mais comumente utilizados para previsão de altura final e enfatizados os problemas de se levantarem, às vezes, falsas expectativas que acabam não se concretizando, com malefícios emocionais muitas vezes imprevisíveis. Há um consenso de que as previsões devem ser fornecidas à família com cautela e ressalvas, principalmente quando se propõem medicações que nem sempre vão garantir aumento de altura final.

When and how to combine growth hormone with a luteinizing hormone-releasing hormone analogue

The effect of combined treatment with growth hormone (GH) and a luteinizing hormone-releasing hormone (LHRH) analogue, or GH alone, on pubertal height gain was assessed in an uncontrolled study in 15 boys and 10 girls with GH deficiency (GHD). Seven boys and six girls were treated with GH alone (group 1), and eight boys and four girls were treated with a combination of GH and an LHRH analogue during puberty (group 2). Mean ages (+/- SD) at the start of GH treatment and at the onset of puberty were significantly lower in group 2 (8.0 +/- 3.3 years and 11.2 +/- 0.8 years, respectively, in boys, and 6.3 +/- 1.6 years and 10.8 +/- 0.7 years in girls) than in group 1 (12.8 +/- 1.9 years and 13.7 +/- 1.4 years in boys, and 11.2 +/- 1.0 years and 12.5 +/- 1.2 years in girls). Height at the onset of puberty was less in group 2 than in group 1, but the difference was significant only for the boys. Combination treatment was started at a mean age of 11.7 +/- 1.2 years in boys and 11.5 +/- 1.0 years in girls. The duration of the combination treatment was 5.1 +/- 1.5 years in boys and 2.3 +/- 0.7 years in girls. The duration of the period between the onset of puberty and the end of GH treatment was significantly longer in group 2 (6.8 +/- 1.2 years in boys and 5.5 +/- 1.0 years in girls) than in group 1 (4.3 +/- 1.6 years in boys and 3.6 +/- 1.4 years in girls). The pubertal height gain was also significantly greater in group 2 (36.7 +/- 6.5 cm in boys and 29.0 +/- 8.3 cm in girls) than in group 1 (21.9 +/- 4.1 cm in boys and 18.6 +/- 4.1 cm in girls). Final height was significantly greater in group 2 than in group 1 in boys. Although there was no significant difference in final height between groups in the girls, the change in height SDS from the start of GH treatment until final height was significantly greater in group 2 (2.7 +/- 1.6 in boys and 4.5 +/- 0.5 SD in girls) than in group 1 (1.0 +/- 0.8 in boys and 1.8 +/- 0.9 SD in girls), in both boys and girls. In conclusion, it appears that combination of an LHRH analogue and GH may increase the pubertal height gain and the final height of children with GHD. The improvement is attributed to the prolongation of the treatment period, permitting slow bone maturation, and to the maintenance of height velocity. This combination treatment appears to be more effective in boys than girls. To fully assess this therapeutic approach, prospective controlled studies are needed.