Adult height in patients treated for isolated growth hormone deficiency: role of birth weight

To evaluate the effect of growth hormone (GH) administration on adult height (AH) in two groups of isolated GH-deficient (IGHD) children born either small (birth weight below -2 SD) or appropriate (birth weight above -2 SD) for gestational age (GA). Out of 35 prepubertal IGHD children, 14 small for GA (SGA, group A) and 21 appropriate for GA (AGA, group B) were examined. All patients received continuous GH treatment at a median dose of 0.028 mg/kg/day (range 0.023-0.032) in group A and 0.024 (range 0.023-0.028) in group B. GH treatment was administered for a period of 67.0 months (range 42.37-96.05) in group A and 54.31 months (range 47.14-69.31) in group B. All children were measured using a Harpenden stadiometer every 6 months until they reached AH (growth velocity <1 cm/year). The patients underwent a retesting a few months after stopping GH therapy. A significant difference was found between group A and B as expected for birth weight SD, -2.70 (range -2.87 to -2.29) and -0.73 (range -1.30 to 0.14) respectively (p < 0.000001) and interestingly also for body mass index SDS (BMI SDS) at retesting, 0.08 (range 0.30 to -1.51) and 0.61 (range 0.73 to -1.10) respectively (p < 0.04). We observed no significant differences between groups A and B in height (expressed as the SDS for chronological age, height SDS) at diagnosis (p = 0.75), height SDS at start of puberty (p = 0.51), height SDS at retesting (p = 0.50), target height SDS (TH SDS) (p = 0.47), AH SDS (p = 0.92), corrected height SDS (height SDS - TH SDS) (p = 0.60), BMI SDS at diagnosis (p = 0.25), GH dosage (p = 0.34) and therapy duration (p = 0.52). GH treatment with a standard dose in short IGHD children leads to a normalization of AH without any significant difference between SGA and AGA patients.     

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.     

Final height data, body composition and glucose metabolism in growth hormone-treated short children born small for gestational age

Low birth weight has been associated with impaired insulin sensitivity, type 2 diabetes mellitus, hypertension and cardiovascular disease in later life. GH therapy is known to increase fasting and postprandial insulin levels. For this reason concern has been expressed regarding the possible detrimental effects of GH therapy in children born small for gestational age (SGA). To assess the effects of GH therapy on body composition, carbohydrate metabolism and final height in short SGA children, 165 prepubertal short children born SGA were enrolled in either a multicentre, double-blind, randomized, dose-response GH trial (n = 75) or in a GH controlled trial (n = 90). The inclusion criteria were: (1) birth length standard deviation score (SDS) below -2; (2) age 3-8 years; (3) height SDS below -2. The children's mean (SD) age was 7.3 (2.1) years (GH dose-response trial) and 6.0 (1.5) years (GH controlled trial), birth length SDS was -3.6 and height SDS was -3.0 (0.7). In the GH dose-response trial, children were randomly assigned to either 1 mg GH/m(2) per day (group A, n = 41) or 2 mg GH/m(2) per day (group B, n = 38) ( approximately 0.033 or 0.067 mg/kg per day, respectively). In the GH controlled trial, children were randomly assigned to 1 mg GH/m(2) per day (n = 60) or served as controls (n = 30). Subjects underwent standard oral glucose tolerance tests and measurement of body mass index, systolic and diastolic blood pressure and serum lipids at baseline and after 1 and 6 years of GH therapy and again 6 months after discontinuation of GH. Body composition was measured by dual energy x-ray absorptiometry at baseline and again after 3 years in the GH controlled trial. Mean (SD) final height SDS was not significantly different between the two GH dosage groups: -1.2 (0.7) in group A and -0.8 (0.7) in group B. At the start of GH therapy, 8% of children had impaired glucose tolerance (IGT). Systolic blood pressure was significantly higher in comparison with healthy peers. GH therapy induced considerably higher fasting and glucose-stimulated insulin levels after 1 and 6 years, regardless of GH dosage. After 6 years, 4% of children had IGT. Six months after discontinuation of GH, glucose levels remained normal, whereas fasting and glucose-stimulated insulin returned to levels comparable to those of healthy peers. None of the children developed diabetes. During 6 years of GH therapy both systolic and diastolic blood pressure decreased significantly and remained so after discontinuation of GH therapy. At baseline all children had reduced bone mineral content and lean body mass. Fat mass was not significantly lower than normal. Treatment with 1 mg GH/m(2) per day resulted in a significant increase in (and normalization of) bone mineral content and lean body mass in comparison with untreated short SGA controls. Fat mass decreased during the first year of GH but returned to values comparable to those at baseline in the following 2 years of GH therapy. We found that long-term, continuous GH therapy in short children born SGA leads to a normalization of height during childhood and to a normal final height in most children, regardless of GH dosage. Only very short or relatively older children may need a dosage of 2 mg GH/m(2) per day. Long-term GH therapy had no adverse effects on glucose levels and serum lipids and had a positive effect on blood pressure, even with GH dosages of up to 2 mg/m(2) per day. However, as has been reported in other patient groups, GH induced higher fasting and glucose-stimulated insulin levels, indicating insulin resistance. After discontinuation of GH serum insulin levels returned to normal age-reference levels. Short SGA children have a reduction in bone mineral content and lean body mass when compared with healthy controls, which significantly improved (normalized) with GH therapy at a dose of 1 mg/m(2) per day.     

Food intake of children with short stature born small for gestational age before and during a randomized GH trial

Parents of short children born SGA often report that their children have a serious lack of appetite and a low food intake. In this study we investigated food intake, by using a standardized 7-day food questionnaire, in 88 short SGA children before start of GH treatment. The intake was compared with the recommended daily intake (RDI) of age-matched children. We also compared the food intake of GH-treated children (n=62) with randomized controls (n=26) after 1 year of GH treatment. In addition, we evaluated the effect of food intake and GH treatment on body composition and serum levels of IGF-I, IGFBP-3 and leptin. Our study shows that caloric intake, fat and carbohydrate intake of short SGA children aged 5.9 (1.6) years was significantly lower compared to the RDI for age-matched children. One year of GH treatment resulted in a significant increase of caloric, fat, carbohydrate and protein intake compared to baseline. Compared to randomized controls, caloric, carbohydrate and protein intake increased significantly after 1 year of GH treatment. Short SGA children had significantly lower SDS scores for LBM, fat mass, skinfold (SF) and BMI compared to age-matched references. They also had significantly lower serum IGF-I, IGFBP-3 and leptin levels. GH treatment resulted in a significant increase of height, LBM, BMI, IGF-I and IGFBP-3 SDS and a significant decrease of SF SDS and leptin SDS. In conclusion, our study shows that short SGA children have indeed a lower food intake than age-matched controls. During GH treatment the food intake increased significantly compared to baseline in contrast to the randomized control group.     

IGF-I and IGF binding protein-3 levels during initial GH dosage step-up are indicators of GH sensitivity in GH-deficient children and short children born small for gestational age

BACKGROUND: A stepwise increment of the GH dose is an approach aimed at avoiding adverse events. We investigated GH sensitivity by studying IGF-I and IGFBP-3 concentrations during the initial phase of GH treatment. METHODS: Our investigation was part of the regular follow-up of prepubertal children with GH deficiency (GHD) (n = 31) and small for gestational age (SGA) (n = 23). Dosage was increased in three steps: one-third at the start, two-thirds after 14 days, and the full dose after 28 days (full dose: GHD = 28 microg/kg body weight (BW)/day; SGA = 60 microg/kg BW/day). Blood samples were taken on days 0, 14 and 28, as well as in conjunction with anthropometrical examinations after 3, 6 and 12 months. IGF-I and IGFBP-3 were measured by means of published in-house RIAs and age-related references were used to calculate standard deviation scores (SDS). Height velocity (cm/year) and Delta HT SDS were taken as growth response parameters. RESULTS: Before GH treatment (GHD vs. SGA; median and p values): age (years) (6.6 vs. 6.0; n.s.), HT SDS (-2.6 vs. -3.2; p < 0.05); GH amount after stepping up (mug/kg BW/day) (28 vs. 60; p < 0.01); BW SDS (-0.5 vs. -2.9; p < 0.01); max. GH stimulated (microg/l) (5.6 vs. 10.8; p < 0.01); IGF-I SDS (-3.5 vs. -1.8; p < 0.01); IGFBP-3 SDS (-2.0 vs. 0.8; p < 0.01). After 1 year of GH therapy: HT velocity (cm/year) (9.8 vs. 9.6; n.s.), Delta HT SDS (0.9 vs. 0.9; n.s.); WT velocity (kg/year) (3.3 vs. 3.5; n.s.). Our results show that changes in growth similar to GHD could be induced in SGA by a dosage that was twice as high as the replacement dose given in GHD. GH dose and HT velocity did not correlate in both groups. IGF-I and IGFBP-3 increased as follows in GHD and SGA during stepping up of the dosage (ng/ml, GHD vs. SGA): at start, 54 vs. 89; at day 14, 78 vs. 132; at day 28, 90 vs. 167; at 3 months, 118 vs. 218. There was the same relationship between dose levels and absolute IGF-I concentrations in both groups. In terms of IGF-I SDS, the dose-response curve in SGA showed a shift to the right in comparison to GHD, thus indicating lower sensitivity to GH. The dynamics of IGF-I and IGFBP-3 differed, as IGFBP-3 peaked earlier (on day 28). In GHD, IGF-I SDS at 3 months was -0.7 vs. +0.9 in SGA. Near-identical levels were found for Delta IGF-I SDS and IGFBP-3 SDS above basal levels for each time-point investigated. First year HT velocity in GHD correlated negatively with basal IGF-I SDS (R(2) = 0.33; p <0.001) and basal IGFBP-3 (R(2) = 0.17; p <0.05) but did not correlate with the IGF-I increment during the 0- to 3-month period. Conversely, first year HT velocity correlated (+) in SGA with the IGF SDS increment during the 0- to 3-month period (R(2) = 0.26; p = <0.05). Height velocity in SGA, however, correlated neither with basal IGF-I and IGFBP-3 nor with the 0- to 3-month increments of IGFBP-3 SDS. CONCLUSIONS: IGFs increase during initial GH therapy, thus raising questions about short-term IGF generation tests. (I) In terms of IGF generation, substantially lower sensitivity to GH was observable in SGA. (II) Higher GH sensitivity during first year catch-up growth is associated with GHD, but in SGA it is attributable to increases in IGF. A wider range of GH dosages needs to be explored in order to gain further insight into the relationship between GH dose, IGF levels, and growth. Monitoring IGFs is a practical means for exploring GH sensitivity during dosage stepping up.     

Growth hormone treatment in short Japanese children born small for gestational age

Recent reports have shown that high-dose growth hormone (GH) treatment in short children born with small for gestational age (SGA) resulted in a pronounced acceleration of linear growth. We describe the results of multicenter trials of recombinant human GH (rhGH) treatment in short SGA children in Japan. Two clinical studies were performed and the results were combined. Study 1 comprised 104 SGA children and study 2 comprised 61 SGA children. The patients were divided into three groups: group 1 consisted of 20 patients (13 boys and 7 girls) who received rhGH 25 microg/kg per day six or seven times per week in the first year and 50 microg/kg per day in the second year and thereafter; group 2 consisted of 48 patients (28 boys, 20 girls) who received rhGH 45/50 microg/kg per day; group 3 consisted of 44 patients (28 boys, 16 girls) who received 90/100 microg/kg per day. The mean increments in height SDS were 0.46, 0.67 and 0.94 SD in boys and 0.49, 0.79 and 0.93 SD in girls in groups 1, 2 and 3, respectively. The mean increment in height SDS at 2 years in group 3 was significantly greater than that in group 1, but it was not significantly different from that in group 2 in boys and girls. Our data demonstrated that high-dose GH administration significantly improved height velocity and height SDS in short SGA children. Additional studies are necessary to optimize a long-term GH treatment regimen and combined luteinizing hormone releasing hormone analog treatment for final height. Careful observation is also necessary to assess the metabolic effects of high-dose GH, especially on carbohydrate metabolism.     

Bone age progression during the first year of growth hormone therapy in pre-pubertal children with idiopathic growth hormone deficiency, Turner syndrome or idiopathic short stature, and in short children born small for gestational age: analysis of data from KIGS (Pfizer International Growth Database)

BACKGROUND/AIMS: The beneficial effects of growth hormone (GH) therapy on statural growth in children are well established, but the effects on skeletal maturation are less clear. The progression of bone age (BA) was therefore studied during the first year of GH treatment in pre-pubertal children with idiopathic GH deficiency (GHD), Turner syndrome (TS) or idiopathic short stature (ISS), and in short pre-pubertal children born small for gestational age (SGA). METHODS: Cross-sectional data on 2,209 short children with idiopathic GHD, 694 with TS, 569 with ISS and 153 with SGA were analysed. Longitudinal data were also analysed from 308 children with idiopathic GHD, 99 with TS, 57 with ISS and 29 with SGA. All patients included in the study were enrolled in KIGS (Pfizer International Growth Database) and were being treated with recombinant human GH (Genotropin). BA was assessed using the Greulich and Pyle method at baseline and after 1 year of GH therapy. RESULTS: In all groups of patients the mean progression of BA was 1 year during the year of GH therapy, although there was considerable individual variation. Progression of BA was not correlated with chronological age, BA, height SD score (SDS) or body mass index SDS at the onset of GH therapy. There was also no consistent effect of the GH dose on BA progression. CONCLUSION: Progression of BA appears to be normal in patients receiving GH in these diagnostic groups, at least over the first year of treatment in pre-puberty.     

Methylphenidate and the Response to Growth Hormone Treatment in Short Children Born Small for Gestational Age

Background

Growth hormone (GH) treatment has become a frequently applied growth promoting therapy in short children born small for gestational age (SGA). Children born SGA have a higher risk of developing attention deficit hyperactivity disorder (ADHD). Treatment of ADHD with methylphenidate (MP) has greatly increased in recent years, therefore more children are being treated with GH and MP simultaneously. Some studies have found an association between MP treatment and growth deceleration, but data are contradictory.

Objective

To explore the effects of MP treatment on growth in GH-treated short SGA children

Methods

Anthropometric measurements were performed in 78 GH-treated short SGA children (mean age 10.6 yr), 39 of whom were also treated with MP (SGA-GH/MP). The SGA-GH/MP group was compared to 39 SGA-GH treated subjects. They were matched for sex, age and height at start of GH, height SDS at start of MP treatment and target height SDS. Serum insulin-like growth factor-I (IGF-I) and IGF binding protein-3 (IGFBP-3) levels were yearly determined. Growth, serum IGF-I and IGFBP-3 levels during the first three years of treatment were analyzed using repeated measures regression analysis.

Results

The SGA-GH/MP group had a lower height gain during the first 3 years than the SGA-GH subjects, only significant between 6 and 12 months of MP treatment. After 3 years of MP treatment, the height gain was 0.2 SDS (±0.1 SD) lower in the SGA-GH/MP group (P = 0.17). Adult height was not significantly different between the SGA-GH/MP and SGA-GH group (−1.9 SDS and −1.9 SDS respectively, P = 0.46). Moreover, during the first 3 years of MP treatment IGF-I and IGFBP-3 measurements were similar in both groups.

Conclusion

MP has some negative effect on growth during the first years in short SGA children treated with GH, but adult height is not affected.     

Growth hormone treatment of short children born small for gestational age: a US perspective

Research during the last decade shows clearly that growth hormone (GH) therapy causes a sustained increase in growth velocity when applied to short children born small for gestational age (SGA). This occurs even though GH deficiency per se is an unlikely explanation for their lack of catch-up growth. In the United States, children born weighing less than -2 SD for gestational age and who show no growth recovery (usually defined as stature persisting below -2 SD at age 2 years) are eligible for GH treatment using doses up to 0.48 mg/kg per week. The management of these children brings new challenges to the pediatric endocrinologist. Intrauterine growth retardation reflects a variety of etiologies, some of which merit special consideration and may respond variably to GH. The dose of GH used exceeds physiologic replacement and is higher than that commonly used to treat other non-GH-deficient conditions such as Turner syndrome. Thus, what constitutes optimal therapy in terms of dose, timing and patient selection remains an important question. While GH therapy provides a means by which one aspect of the SGA syndrome can be helped, there are other issues for SGA apart from height. Future efforts should include studies that better define how GH should be used in the short child born SGA and address more broadly the medical, social and psychological needs of these patients.     

Final height of growth hormone-treated GH-deficient children and girls with Turner's syndrome: the Dutch experience. The Dutch Advisory Group on Growth Hormone

In the Dutch growth hormone (GH) registration database there are currently 552 GH-deficient children being treated, subcutaneously, with recombinant human GH six to seven times per week. Of those, 112 who have been treated for at least 2 years have reached final height. Mean age at start of therapy was 11.70 years. Mean GH dose was 15.5 IU/m(2) body surface per week. Mean final height was 173.2 cm (boys) and 159.7 cm (girls) and -1.36 SD of the population mean. Of the patients, 73.2% and 63.4%, respectively, reached a final height above -2 SD of the population or within target limits. FH-SDS was higher compared with the results of earlier cohorts with different treatment regimens. Target height, GH peak value at diagnosis, age at start of GH therapy, height SDS (HSDS) at start of puberty, and duration of GH therapy were significantly correlated with final height. These results, combined with those of a prospective GH dose-response study, suggest that better long-term results can be obtained with early and prolonged treatment and if the GH dose is individually adapted to the short-term growth response. In an ongoing dose-response study, 68 girls with Turner's syndrome, aged 2-11 years, were randomized into three dosage groups with a daily GH dose of: (group A) 4 IU/m(2) body surface; (group B) 4 IU/m(2) in the first year of therapy and 6 IU/m(2) thereafter; (group C) 4 IU/m(2) in the first year, 6 IU/m(2) in the second year, and 8 IU/m(2) thereafter. After 4 years of GH therapy, girls aged 12 years or older started low-dose oestrogen therapy. After 7 years of GH therapy, mean HSDS in all three groups had increased to values above the third percentile for healthy girls. Mean final height and final height gain of 25 girls was 159.1 and 12.5 cm, 161.8 and 14.6 cm, and 162.7 and 16.0 cm in groups A, B and C respectively. These long-term and final height results are more favourable than the results of earlier Dutch Turner's syndrome studies. Possible explanations are the higher GH doses and/or the younger age at start of GH therapy.     

Growth hormone treatment strategy for short children born small for gestational age

Several studies performed in the last 15 years have shown that growth hormone (GH) induces a profound catch-up in height in short children born small for gestational age (SGA). We know from more recent studies that final height can be normalized through GH treatment. In Europe, GH is now a recognized indication, enabling treatment of short children born SGA. Treatment is given to the most severe growth-retarded children after the age of 4 years. A dose of 0.035 mg/kg per day is recommended. However, in our opinion a higher dose would be more efficient in very short children, especially if they are treated later in childhood.     

Quality of life in adolescents born small for gestational age: does growth hormone make a difference?

BACKGROUND/AIMS: To evaluate quality of life (QoL) in adolescents born SGA without spontaneous catch-up growth, treated with and without long-term growth hormone (GH) therapy. Additionally, to assess whether GH treatment has a positive effect on QoL, besides improving adult height and height SDS during childhood. METHODS: Two groups of adolescents born SGA without spontaneous catch-up growth participated in the QoL evaluation; a GH-treated group (n = 44, mean GH duration: 8.8 (1.7) years) and an untreated group (n = 28), both mean age 15.8 (2.1) years. QoL was measured by self-reports of the TACQOL-S, a disorder-specific questionnaire, and the CHQ, a generic questionnaire. RESULTS: The GH group scored significantly better health status and health-related QoL on several scales of the TACQOL-S. On all TACQOL-S scales the GH group scored better QoL than the untreated group, with effect sizes of moderate to large, not all differences reaching statistical significance. The generic CHQ did not reveal significant differences in QoL between the GH group and the untreated group. CONCLUSIONS: Firstly, adolescents born SGA, with a GH-induced improved height, had in many aspects a better QoL than untreated adolescents born SGA, according to the disorder-specific questionnaire. Secondly, we advise to use, in addition to a generic questionnaire, a disorder-specific questionnaire for measuring QoL in children treated for short stature, as the generic CHQ did not reveal such differences.     

Growth hormone therapy in short children born small for gestational age

There is still a lack of data from randomized, controlled, long-term studies of growth hormone (GH) treatment in children born small for gestational age (SGA), but the available evidence indicates consistently that GH therapy is a valid growth-promoting treatment in these children, particularly if started early. Whilst side effects appear uncommon, ongoing surveillance is required and treated children should be monitored for changes in glucose homeostasis, lipid profiles and blood pressure, especially during puberty. We provide an update on the safety and efficacy of GH treatment in short children born SGA.     

Effect of different growth hormone dosages on the growth velocity in children born small for gestational age

To assess whether short-term growth hormone (GH) treatment can improve the linear growth in children who were born small for gestational age (SGA), we started a randomized multicenter trial in 26 age- and sex-matched prepubertal children born SGA. During the 1st year of GH therapy, all children received GH 0.23 mg/kg/week, then during the 2nd year, 13 children received the same dose (group A), and in the other 13 children, the dose of GH was doubled, i.e., 0.46 mg/kg/week (group B). During the 1st year of therapy, the growth velocity significantly (p<0.0001) increased in all patients. During the 2nd year, group A showed a significant decrease of the growth velocity (p<0.015), whereas group B maintained the growth rate. The height in group A children significantly increased during the 1st and the 2nd year of GH therapy (p<0.000002 and p<0.000001, respectively), reaching the normal range in 8 out of 13 children at the end of 2 years of GH therapy. The height in group B children significantly increased during the 1st and the 2nd year of GH therapy (p<0.000001 and p<0.000001, respectively), reaching the normal range in all 11 children who completed the GH therapy. The height gain was similar in groups A and B treated with the same GH dosage during the 1st year of therapy. A greater increase in height gain was found in children of group B treated with the higher GH dosage during the 2nd year of therapy as compared with group A (p<0.02). Significant increases in insulin-like growth factor I (p<0.0001), acid-labile subunit (p<0.0002), and bone/chronological age ratio (p<0.0001) were found after the 1st year of GH therapy, but no significant changes were observed during the 2nd year, independently of the GH dose. In conclusion, the height velocity of children born SGA significantly increases during the 1st year of GH therapy, diminishes, but can decrease during the 2nd year, if the GH dosage is not raised.     

Depression,smoking, physical inactivity and season independently associated with midnight salivary cortisol in type 1 diabetes

Background

Trisomy 9p is an uncommon anomaly characterised by mental retardation, head and facial abnormalities, congenital heart defects, kidney abnormalities, and skeletal malformations. Affected children may also show growth and puberty retardation with delayed bone age. Auxological and endocrinological data are lacking for this syndrome.

Methods

We describe three girls and one boy with 9p trisomy showing substantial growth failure, and we evaluate the main causes of their short stature.

Results

The target height was normal in all families, ranging from 0.1 and -1.2 standard deviation scores (SDS). The patients had a low birth-weight (from -1.2 to -2.4 SDS), birth length (from -1.1 to -3.2 SDS), and head circumference (from -0.5 to -1.6 SDS). All patients presented with substantial growth (height) retardation at the time of 9p trisomy diagnosis (from -3.0 to -3.8 SDS). The growth hormone stimulation test revealed a classic growth hormone (GH) deficiency (GHD) in patients 1, 3, and 4. In contrast, patient 2 was determined to have a GH neurosecretory dysfunction (GHNSD). The plasma concentrations of IGF-I and IGFBP-3 were low in all patients for their ages and sexes (from -2.0 to -3.4 SDS, and from -1.9 to -2.8 SDS, respectively). The auxological follow-up showed that those patients who underwent rhGH treatment exhibited a very good response to the GH therapy, whereas patients 3 and 4, whose families chose not to use rhGH treatment, did not experience any significant catch-up growth.

Conclusions

GH deficiency appears to be a possible feature of patients with 9p trisomy syndrome. These patients, particularly those with growth delays, should be evaluated for GH secretion.     

Serum leptin in short children born small for gestational age: dose-dependent effect of growth hormone treatment

OBJECTIVE: To study the effects of different regimens of growth hormone (GH) treatment on serum leptin levels in 78 short prepubertal children born small for gestational age (SGA). METHODS: The children were originally included in two independent multicenter trials, one in Belgium and one in the Nordic countries. SGA children were randomized either to remain untreated or to be treated with GH at a daily dose of 0.1, 0.2 or 0.3 IU/kg for 2 years. Thereafter, treatment was continued for another 2 years in the Nordic children, whereas it was discontinued in the Belgian children. RESULTS: In the GH treatment groups, a significant dose-dependent decrease in leptin levels was found during the first year of therapy, with a mean decrease of 13, 23 and 32% in the groups receiving GH at 0.1, 0.2 and 0.3 IU/kg, respectively. When high-dose treatment was interrupted, serum leptin increased within 1 year to pretreatment levels. CONCLUSION: Serum leptin levels in short children born SGA are transiently reduced by GH treatment in a dose-dependent fashion. The most pronounced changes in serum leptin were documented within the first year after initiation and withdrawal of high-dose GH treatment.     

Neurocognitive development in children experiencing intrauterine growth retardation and born small for gestational age: pathological, constitutional and therapeutic pathways

Interest in the neurocognitive and psychosocial outcomes in children who are born small for gestational age (SGA) has increased since the recent approval of growth hormone (GH) therapy in this indication. The objective of GH treatment in SGA children is to provide a symptomatic treatment for growth retardation. From a patient perspective, the ultimate goals of GH therapy are the reduction in the present or future risk of neurocognitive, psychological, social or occupational impairment, not the accompanying improvements in growth velocity and final height per se. Therefore, from a scientific perspective, neurocognitive and psychosocial endpoints become relevant domains of assessment to determine the final treatment benefit experienced by the patient born SGA. This article reviews recent available studies on developmental risks in SGA, and then transforms the empirical findings into an integrated conceptual framework on the sources and mediators of neurocognitive and psychosocial outcomes in intrauterine growth retardation and SGA. This framework depicts two distinct therapeutic pathways by which GH therapy may improve neurocognitive and behavioural outcomes. The first ('traditional') pathway is the prevention of exposure to short-stature-related stressors via an improvement in growth velocity and final height. The second pathway refers to potential metabolic, and thus neurotropic and psychotropic, effects of GH binding at receptors in the central nervous system, thus changing neuronal activity. To date, the existence and potential mechanisms of such physiologically and not psychologically mediated effects of GH on neurocognitive functioning in SGA patients remain hypothetical.     

Adult height distribution in subjects born small for gestational age

The aim of the study was to investigate the post-natal growth of subjects born small for gestational age (SGA) by describing adult height distribution and by testing the effects of parental, neonatal and pregnancy-related parameters on the risk for adult short stature. The study population was made of adults selected on birth data from a maternity registry and born either small (SGA, n = 734, birth weight < 10th percentile) or appropriate for gestational age (AGA, n = 886, 25th < birth weight < 75th percentile) in whom anthropometric parameters were measured at 22 years of age. The SGA group demonstrated significantly reduced body size in comparison to the AGA group with a mean loss of 0.7 standard deviation (SD) in adult height. The frequency of adult short stature (< -2 SD) was 10.3% in the SGA group vs. 2.4% in the AGA group (p = 0.0001), adult height < -2.5 SD was observed in only 3.7% of the SGA group. Maternal (OR = 0.31 (0.16-0.62), p = 0.0001) and paternal (OR = 0.45 (0.31-0.67), p = 0.0001) heights and subjects birth length (OR = 0.78 (0.62-0.99), p = 0.04) significantly influenced the risk of adult short stature. In summary, post-natal growth defect remains moderate in the majority of subjects born SGA and < 4% only will end up with severe short stature requiring GH therapy according to most current recommendations. The role of parental height and birth length suggests that adult short stature in SGA subjects results at least in some cases from a familial and likely genetic growth disorder with antenatal onset.     

DNA methylation of IGF2, GNASAS,INSIGF and LEP and being born small for gestational age

Being born small for gestational age (SGA), a proxy for intrauterine growth restriction (IUGR) and prenatal famine exposure are both associated with a greater risk of metabolic disease. Both associations have been hypothesized to involve epigenetic mechanisms. We investigated whether prenatal growth restriction early in pregnancy was associated with changes in DNA methylation at loci that were previously shown to be sensitive to early gestational famine exposure. We compared 38 individuals born preterm (<32 weeks) and with a birth weight too low for their gestational age (less than −1SDS; SGA) with 75 individuals born preterm but with a birth weight appropriate for their gestational age (greater than −1SDS) and a normal postnatal growth (greater than −1SDS at three months post term; AGA). The SGA individuals were not only lighter at birth, but also had a smaller length (p = 3.3 × 10⁻¹³) and head circumference at birth (p = 4.1 × 10⁻¹³). The DNA methylation levels of IGF2, GNASAS, INSIGF and LEP were 48.5, 47.5, 79.4 and 25.7% respectively. This was not significantly different between SGA and AGA individuals. Risk factors for being born SGA, including preeclampsia and maternal smoking, were also not associated with DNA methylation at these loci. Growth restriction early in development is not associated with DNA methylation at loci shown to be affected by prenatal famine exposure. Our and previous results by others indicate that prenatal growth restriction and famine exposure may be associated with different epigenetic changes or non-epigenetic mechanisms that may lead to similar later health outcomes.Key words: SGA, DOHAD, IUGR, DNA methylation, famine, IGF2, LEP, INS, GNASAS     

The p53 family member p73 modulates the proproliferative role of IGFBP3 in short children born small for gestational age

The regulation of insulin-like growth factor–binding protein 3 (IGFBP3) gene expression is complex, because it can be induced by agents that both stimulate and inhibit the proliferation. The principal aim of this study was to investigate whether p73, a member of the p53 gene family, has a role in the regulation of the IGFBP3 expression and whether this regulation occurs in a context of cell survival or death. We demonstrate that IGFBP3 is a direct TAp73α (the p73 isoform that contains the trans-activation domain) target gene and activates the expression of IGFBP3 in actively proliferating cells. As IGFBP3 plays a key role in regulating the growth hormone/insulin-like growth factor type 1 (GH/IGF1) axis, whose alterations in gene expression appear to have a role in the growth failure of children born small for gestational age (SGA), we measured the mRNA expression levels of p73 and IGFBP3 in a group of SGA children. We found that mRNA expression levels of p73 and IGFBP3 are significantly lower in SGA children compared with controls and, in particular, p73 mRNA expression is significantly lower in SGA children with respect to height. Our results shed light on the intricate GH/IGF pathway, suggesting p73 as a good biomarker of the clinical risk for SGA children to remain short in adulthood.