Insights from an advisory board: Facilitating transition of care into adulthood in brain cancer survivors with acquired pediatric growth hormone deficiency

OBJECTIVE

Children with growth hormone deficiency (GHD) face multiple challenges that can negatively impact the transition from pediatric to adult endocrinology care. For children with GHD resulting from brain cancer or its treatment, the involvement of oncology care providers and possible disease-related comorbidities add further complexity to this transition.

DESIGN

An advisory board of pediatric and adult endocrinologists was convened to help better understand the unique challenges faced by childhood cancer survivors with GHD, and discuss recommendations to optimize continuity of care as these patients proceed to adulthood. Topics included the benefits and risks of growth hormone (GH) therapy in cancer survivors, the importance of initiating GH replacement therapy early in the patient's journey and continuing into adulthood, and the obstacles that can limit an effective transition to adult care for these patients.

RESULTS/CONCLUSIONS

Some identified obstacles included the need to prioritize cancer treatment over treatment for GHD, a lack of patient and oncologist knowledge about the full range of benefits provided by long-term GH administration, concerns about tumor recurrence risk in cancer survivors receiving GH treatment, and suboptimal communication and coordination (e.g., referrals) between care providers, all of which could potentially result in treatment gaps or even complete loss of follow-up during the care transition. Advisors provided recommendations for increasing education for patients and care providers and improving coordination between treatment team members, both of which are intended to help improve continuity of care to maximize the health benefits of GH administration during the critical period when childhood cancer survivors transition into adulthood.

Pituitary Neoplasm Nomenclature Workshop: Does Adenoma Stand the Test of Time?

The WHO Classification of Endocrine Tumours designates pituitary neoplasms as adenomas. A proposed nomenclature change to pituitary neuroendocrine tumors (PitNETs) has been met with concern by some stakeholder groups. The Pituitary Society coordinated the Pituitary Neoplasm Nomenclature (PANOMEN) workshop to address the topic. Experts in pituitary developmental biology, pathology, neurosurgery, endocrinology, and oncology, including representatives nominated by the Endocrine Society, European Society of Endocrinology, European Neuroendocrine Association, Growth Hormone Research Society, and International Society of Pituitary Surgeons. Clinical epidemiology, disease phenotype, management, and prognosis of pituitary adenomas differ from that of most NETs. The vast majority of pituitary adenomas are benign and do not adversely impact life expectancy. A nomenclature change to PitNET does not address the main challenge of prognostic prediction, assigns an uncertain malignancy designation to benign pituitary adenomas, and may adversely affect patients. Due to pandemic restrictions, the workshop was conducted virtually, with audiovisual lectures and written précis on each topic provided to all participants. Feedback was collated and summarized by Content Chairs and discussed during a virtual writing meeting moderated by Session Chairs, which yielded an evidence-based draft document sent to all participants for review and approval. There is not yet a case for adopting the PitNET nomenclature. The PANOMEN Workshop recommends that the term adenoma be retained and that the topic be revisited as new evidence on pituitary neoplasm biology emerges.

SAT-252 Risk Behaviors and Metabolic Syndrome in Adolescents

Objective: to evaluate risk behaviors for obesity and components of metabolic syndrome in adolescents. Methods: An observational, descriptive, cross-sectional study, in which 120 individuals were evaluated, ages between 14-19 years, students from both morning and night periods of a public school in Curitiba. Results: 34.7% of the students presented body mass index higher than expected for their age. Normal or borderline values were observed for blood pressure in 91.1% of the students and for abdominal circumference in 95.2%. Only 29.1% of them reported physical activities for more than 300minutes/week; 2 hours/day or more watching TV or playing videogames, activities considered sedentary, were reported by 17,3% and 23,6%, respectively. Presence of metabolic syndrome was higher in students from the night period (OR= 4,72). 34 students (30,9%) reported they smoked or had smoked and only 26 (23,4%) reported they had never drunk alcoholic beverages. Conclusion: frequency of excess weight was higher in our study than previous reports in national studies. The prevalence of hypertension and abdominal obesity was considered low. Components of metabolic syndrome were more frequent in students from the evening period. Key Words: adolescents, obesity, blood pressure, cardiovascular risk, risk behavior. References: 1. Nascimento-Ferreira MV, Moraes ACF, Carvalho HB, Moreno LA, Carneiro ALG, Reis VMM, et al. Prevalence of cardiovascular risk factors, the association with socioeconomic variables in adolescents from low-income region. Nutr Hosp. 2015;31(1):217-224 2. Brito AL, Hardman CM, Barros MVG. Prevalência e fatores associados à simultaneidade de comportamentos de risco à saúde em adolescentes. Rev Paul Pediatr. 2015;33(4):423-430 3. Silva AO, Silva MV, Pereira LK, Feitosa WM, Ritti-Dias RM, Diniz PR, Oliveira LM. Association between general and abdominal obesity with high blood pressure: difference between genders. J Pediatr(rio J). 2015 4.Silva FMA, Smith-Menezes A, Duarte MFS. Consumption of fruits and vegetables associated with other risk behaviors among adolescents in Northeast Brazil. Rev Paul Pediatr. 2016

Growth Hormone Research Society perspective on biomarkers of GH action in children and adults

OBJECTIVE

The Growth Hormone Research Society (GRS) convened a Workshop in 2017 to evaluate clinical endpoints, surrogate endpoints and biomarkers during GH treatment of children and adults and in patients with acromegaly.

PARTICIPANTS

GRS invited 34 international experts including clinicians, basic scientists, a regulatory scientist and physicians from the pharmaceutical industry.

EVIDENCE

Current literature was reviewed and expert opinion was utilized to establish the state of the art and identify current gaps and unmet needs.

CONSENSUS PROCESS

Following plenary presentations, breakout groups discussed questions framed by the planning committee. The attendees re-convened after each breakout session to share the group reports. A writing team compiled the breakout session reports into a document that was subsequently discussed and revised by participants. This was edited further and circulated for final review after the meeting. Participants from pharmaceutical companies were not part of the writing process.

CONCLUSIONS

The clinical endpoint in paediatric GH treatment is adult height with height velocity as a surrogate endpoint. Increased life expectancy is the ideal but unfeasible clinical endpoint of GH treatment in adult GH-deficient patients (GHDA) and in patients with acromegaly. The pragmatic clinical endpoints in GHDA include normalization of body composition and quality of life, whereas symptom relief and reversal of comorbidities are used in acromegaly. Serum IGF-I is widely used as a biomarker, even though it correlates weakly with clinical endpoints in GH treatment, whereas in acromegaly, normalization of IGF-I may be related to improvement in mortality. There is an unmet need for novel biomarkers that capture the pleiotropic actions of GH in relation to GH treatment and in patients with acromegaly.

Short Children with CHARGE Syndrome: Do They Benefit from Growth Hormone Therapy?

AIM

The aim of this study was to evaluate the response to recombinant growth hormone (GH) treatment in short children with CHARGE syndrome.

PATIENTS

We identified 51 children (28 boys and 23 girls) in KIGS (Pfizer International Growth Database). The median chronological age was 7.6 years at the start of GH therapy and 13.2 years at the latest visit. Evaluation for GH deficiency (n = 33) was based on the following: peak GH level 7.3 μg/l and IGF-I level -2.01 standard deviation score (SDS). Sixteen subjects (9 boys) were followed longitudinally for 2 years.

RESULTS

Birth length (median SDS, -0.47) and weight (-0.97) were slightly reduced. At the start of GH therapy, height was -3.6 SDS, BMI -0.7 SDS, and the GH dose was 0.26 mg/kg/week. At the latest visit after 2.7 years of GH therapy, height had increased to -2.2 SDS and BMI to -0.5 SDS. In the longitudinal group, height increased from -3.72 SDS at the start of GH therapy to -2.92 SDS after 1 year to -2.37 SDS after 2 years of therapy (start - 2 years: p < 0.05), height velocity increased from -1.69 to 2.98 to 0.95 SDS, and BMI and GH dose (mg/kg/week) remained almost unchanged.

CONCLUSIONS

Our data show a positive effect of conventional doses of GH on short-term growth velocity for the longitudinal as well as for the total group, without any safety issues.

GH safety workshop position paper: a critical appraisal of recombinant human GH therapy in children and adults

Recombinant human GH (rhGH) has been in use for 30 years, and over that time its safety and efficacy in children and adults has been subject to considerable scrutiny. In 2001, a statement from the GH Research Society (GRS) concluded that 'for approved indications, GH is safe'; however, the statement highlighted a number of areas for on-going surveillance of long-term safety, including cancer risk, impact on glucose homeostasis, and use of high dose pharmacological rhGH treatment. Over the intervening years, there have been a number of publications addressing the safety of rhGH with regard to mortality, cancer and cardiovascular risk, and the need for long-term surveillance of the increasing number of adults who were treated with rhGH in childhood. Against this backdrop of interest in safety, the European Society of Paediatric Endocrinology (ESPE), the GRS, and the Pediatric Endocrine Society (PES) convened a meeting to reappraise the safety of rhGH. The ouput of the meeting is a concise position statement.

Insulin-like growth factor 1 gene (CA)n repeats and a variable number of tandem repeats of the insulin gene in Brazilian children born small for gestational age

OBJECTIVE

To investigate the influence of (CA)n repeats in the insulin-like growth factor 1 gene and a variable number of tandem repeats of the insulin gene on birth size in children who are small or adequate-sized for gestational age and to correlate these polymorphisms with serum insulin-like growth factor 1 levels and insulin sensitivity in children who are small for gestational age, with and without catch-up growth.

PATIENTS AND METHODS

We evaluated 439 infants: 297 that were adequate-sized for gestational age and 142 that were small for gestational age (66 with and 76 without catch-up). The number of (CA)n repeat in the insulin-like growth factor 1 gene and a variable number of tandem repeats in the insulin gene were analyzed using GENESCAN software and polymerase chain reaction followed by enzymatic digestion, respectively. Clinical and laboratory data were obtained from all patients.

RESULTS

The height, body mass index, paternal height, target height and insulin-like growth factor 1 serum levels were higher in children who were small for gestational age with catch-up. There was no difference in the allelic and genotypic distributions of both polymorphisms between the adequate-sized and small infants or among small infants with and without catch-up. Similarly, the polymorphisms were not associated with clinical or laboratory variables.

CONCLUSION

Polymorphisms of the (CA)n repeats of the insulin-like growth factor 1 gene and a variable number of tandem repeats of the insulin gene, separately or in combination, did not influence pre- or postnatal growth, insulin-like growth factor 1 serum levels or insulin resistance.

Unique gene expression profile associated with an early-onset multiple endocrine neoplasia (MEN1)-associated pituitary adenoma

CONTEXT

Multiple endocrine neoplasia type 1 (MEN1) is caused by mutations in the menin (MEN1) gene. The mechanism(s) by which MEN1 mutations lead to pituitary tumor formation remain(s) unknown.

OBJECTIVE

The aim of the study was to identify the pediatric MEN1-associated pituitary tumor transcriptome.

PATIENTS AND METHODS

A patient harboring a MEN1 mutation (c.525C>G; p.H139D) who presented with an early-onset mammosomatotroph pituitary adenoma was studied. Microarray analysis was performed in the tumor sample and compared with the profile observed in normal pituitaries and in a sporadic mammosomatotropinoma. Validation of the microarray results was performed using quantitative real-time PCR and immunohistochemical analysis for selected genes.

RESULTS

In the MEN1-associated pituitary adenoma, 59 and 24 genes were found to be significantly up- and down-regulated, respectively. The up-regulated genes included those involved in cell growth and maintenance, apoptosis, growth arrest, and tumorigenesis. Moreover, we observed decreased expression in genes neuroendocrine in nature and related to growth or apoptosis. Only 21 of the 59 genes differentially expressed in the MEN1-associated adenoma showed a similar expression profile to that seen in the sporadic mammosomatotropinoma; for some genes an opposite expression profile was observed.

CONCLUSIONS

We identified changes in the transcriptome that occur in pituitary GH- and PRL-producing cells after the loss of menin expression; some of the gene changes are necessary for tumor evolution, and others may be tertiary. Nevertheless, the rare overlap between the expression profiles of the MEN1 tumor vs. that of its sporadic counterpart suggests that these tumors evolve along different molecular pathways.

Leptin levels at birth and in early postnatal life in small- and appropriate-for-gestational-age infants

The aim of this study was to evaluate leptin concentration at birth and in early postnatal life in small- and appropriate-for-gestational-age infants and to assess its relationship with infants' anthropometry at birth and some characteristics of maternal pregnancy.

MATERIALS AND METHODS

A total of 367 infants born after 32-42 weeks of gestation were enrolled in the study. Umbilical cord blood samples were collected from 80 small- and 287 appropriate-for-gestational-age newborns. Altogether, 166 venous blood samples were taken from these neonates on days 2-6 of life.

RESULTS

Cord leptin levels were significantly lower in small- compared to appropriate-for-gestational-age infants. We observed a positive correlation between cord leptin and birth weight, all neonatal anthropometric parameters, placental weight, and some maternal nutritional factors. In multivariate analysis, cord leptin concentration explained up to 15% of the variation in sum of newborn's skinfold thickness but only 5% of the variation in birth weight. Postnatally, leptin concentration decreased markedly to the similar low levels in both infant groups and remained so during the first postnatal week.

CONCLUSIONS

Significantly lower cord leptin concentration in small-for-gestational-age neonates reflects a lower fat mass content compared to appropriate-for-gestational-age infants. However, an abrupt decrease in leptin levels shortly after birth in both groups suggests that placenta could be an important source of leptin in fetal circulation. The impact of low leptin levels at birth in small-for-gestational-age infants on their postnatal appetite and weight gain remains to be elucidated in future studies.

IGF-I is critical for normal vascularization of the human retina

Experimental and clinical studies suggest that GH and IGF-I may be involved in neovascularization of the retina in diabetes and retinopathy of prematurity. However, the role of GH and IGF-I has not been well established in normal retinal vessel development in humans. Therefore, we examined retinal vessel morphology by digital image analysis of ocular fundus photographs in 13 patients with genetic defects of the GH/IGF-I axis and low levels of IGF-I during and after normal retinal vessel growth. Eleven patients (four females and seven males aged 10-49 yr) had defects of the GH receptor (Laron syndrome). One male (20 yr) had a partial deletion of the IGF-I gene, and one female (14 yr) had a single allele deletion of the IGF-I receptor gene. Patients with defects in the GH/IGF-I axis had significantly less retinal vascularization as evidenced by lower number of vascular branching points (median 23, range 16-25), compared with the reference group of 100 normal controls (median 28, range 19-40, P < 0.001). All 13 individuals had vascular branching points below the median of the reference group. This is the first study to provide genetic evidence for a role of the GH and IGF-I system in retinal vascularization in humans.

Children born small-for-gestational age: postnatal growth and hormonal status

It is generally recognized that children born small-for-gestational age (SGA) have a 5-7 times higher risk of short stature than children born at normal size. It has been suggested that the programming of the endocrine axes occurs during critical phases of fetal development and is affected by intrauterine growth retardation. This study was undertaken to characterize the postnatal growth pattern and the final height of children born SGA, as part of a population- based study (n = 3,650), from birth to final height, and to evaluate the hormonal status in another group of prepubertal children born SGA (n = 134) without postnatal catch-up growth. The majority (88%) of 'healthy' full-term singleton SGA infants achieved catch-up growth during the first 2 years of life, and most of the increase in height occurred by 2 months of age. The SGA children who remained short at 2 years of age had a higher risk of short stature later in life. The risk of having a short final height (<-2 SDS) was five times higher for children with a low birth weight and seven times higher for those with a low birth length in comparison with children with a normal birth size. Moreover, about 20% of all children of short stature were born SGA. As a group, children born SGA will have a final height, expressed in SDS, as they had during the prepubertal years. This is in contrast to children, who became short postnatally. During puberty, these short children will have a mean height gain of 0.6 SDS for girls and 0.7 SDS for boys. The mean estimated secretion rate for growth hormone (GH) was lower in the short children born SGA compared with the reference groups born at an appropriate size for gestational age, of either short (p < 0.05) or normal stature (p < 0.001). Moreover, in the youngest children born SGA (2-6 years of age) a different pattern of GH secretion was found, with a high basal GH level, low peak amplitude, and high peak frequency. The majority of the children born SGA had levels of GH-binding protein within the range previously reported for normal children. However, the levels of insulin-like growth factor I (IGF-I), IGF-binding protein-3 (IGFBP-3) and leptin were significantly reduced compared with the reference values (p < 0.001, p < 0.01 and p < 0.001, respectively). In conclusion, the low spontaneous GH secretion rate and a disturbed GH secretion pattern, together with low serum levels of IGF-I, IGFBP-3 and leptin, might contribute to the reduced postnatal growth in some of the subgroup of children born SGA who remained short during childhood.

Adrenal steroid hormones in short children born small for gestational age

OBJECTIVE

Programming of the endocrine axis has been postulated to occur during critical phases of fetal development and is affected by intrauterine growth retardation. The aim of this study was to investigate this hypothesis with regard to adrenal steroid hormones. Thus, serum cortisol and dehydroepiandrosterone sulphate (DHEAS) levels were compared in children born small for gestational age (SGA) who remained short and in children born at an appropriate size for gestational age (AGA), of both short and normal stature.

DESIGN AND PATIENTS

Seven serum samples for cortisol measurements were taken during a 24-h period from a total of 184 prepubertal individuals. The study group comprised 53 children born SGA who remained short (41 boys, 12 girls; mean chronological age, 8.8 +/- 2.5 years). The reference groups of children born AGA were as follows: 75 healthy short children (56 boys, 19 girls; mean chronological age, 10.8 +/- 2.6 years) and 56 healthy children of normal height (37 boys, 19 girls; mean chronological age, 11.3 +/- 1.8 years). A single serum sample for measurement of DHEAS was taken between 1000 and 1400 h in 110 of the 184 children (33 short SGA, 42 short AGA and 35 AGA of normal height).

MEASUREMENTS

Serum cortisol and DHEAS were measured by radioimmunoassay.

RESULTS

No differences were found between children born SGA and children born AGA in either cortisol levels, calculated as area under the curve (AUC), or the circadian cortisol rhythm, estimated from the calculated nadir, the peak and the amplitude. No difference between the groups was found for serum DHEAS concentrations. Serum cortisol levels, expressed as AUC, and serum DHEAS levels did not correlate with size at birth. However, when adjusted for age at investigation, serum DHEAS, but not serum cortisol, correlated with weight at birth.

CONCLUSIONS

Serum cortisol levels and rhythms do not correlate with size at birth and are similar in children born small for gestational age who remain short and children born appropriate size for gestational age of both short and normal stature. However, DHEAS levels in young children before adrenarche correlated inversely with weight at birth, indicating a relationship with fetal growth.

Growth hormone treatment of short children born small-for-gestational-age: the Nordic Multicentre Trial

The aims of this study were to evaluate the efficacy and safety of different doses of growth hormone (GH) treatment in prepubertal short children born small-for-gestational-age (SGA). Forty-eight children born SGA from Sweden, Finland, Denmark and Norway were randomly allocated to three groups: a control group of 12 children received no treatment for 2 y, one group was treated with GH at 0.1 IU/kg/d (n=16), and one group was treated with GH at 0.2 IU/kg/d (n=20). In total 42 children completed 2 y of follow-up, and 24 children from the treated groups completed 3 y of treatment. Their mean (SD) age at the start of the study was 4.69 (1.61) y and their mean (SD) height was -3.16 (0.70) standard deviation scores (SDS). The children remained prepubertal during the course of the study. No catch-up growth was observed in the untreated group, but a clear dose-dependent growth response was found in the treated children. After the third year of treatment, the group receiving the higher dose of GH, achieved their target height. The major determinants of the growth response were the dose of GH used, the age at the start of treatment (the younger the child, the better the growth response) and the family-corrected individual height deficit (the higher the deficit, the better the growth response). Concentration of insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 increased during treatment. An increase in insulin levels was found without negative effects on fasting glucose levels or glycosylated haemoglobin levels. GH treatment was well tolerated. In conclusion, short prepubertal children born SGA show a dose-dependent growth response to GH therapy, and their target height SDS can be achieved within 3 y of treatment given GH at 0.2 IU/kg/d. However, the long-term benefit of different regimens of GH treatment in children born SGA remains to be established.

Hormonal status of short children born small for gestational age

The present study was undertaken to evaluate the hormonal status in a subgroup of prepubertal children born small for gestational age (SGA) who lacked postnatal catch-up growth. In this subgroup, a reduced rate of growth hormone (GH) secretion was found, compared with reference groups of healthy children born appropriate for gestational age, of either normal or short stature at the time of investigation. In addition, an abnormal pattern of GH secretion was observed in short children born SGA, which was most pronounced in the younger children, and involved an increased frequency of GH peaks of low amplitude, combined with increased baseline secretion. Levels of insulin-like growth factor I (IGF-I) and IGF-binding protein-3 were also reduced in short children born SGA, compared with the reference groups. These findings may explain, in part, the lack of postnatal catch-up growth in short children born SGA.

Serum leptin in short children born small for gestational age: relationship with the growth response to growth hormone treatment. The Swedish Study Group for Growth Hormone Treatment

The product of the obese (ob) gene, leptin, is an adipocyte-derived hormone that is involved in the regulation of appetite and body weight. This study was undertaken in order to describe the basal serum levels of leptin in prepubertal short children born small for gestational age (SGA) and their relationship with growth parameters, before and during growth hormone (GH) treatment. Eighty-nine prepubertal short children (66 boys, 23 girls; height standard deviation score (SDS), -5.4 to -2.0; age, 2.0 to 12.8 years) born SGA, 12 of whom (9 boys, 3 girls) had signs of Silver-Russell syndrome, were included in the study. Serum leptin concentrations were measured by radioimmunoassay. Leptin levels in the children born SGA were compared with those in a reference group of 109 prepubertal healthy children born at an appropriate size for gestational age (AGA). The mean (S.D.) change in height SDS was 0.11 (0.22) during the year before the start of GH therapy (0.1 IU/kg/day) and increased to 0.82 (0.44) during the first year (P < 0.001) and to 1.28 (0.59) during the 2-year period of GH therapy (P < 0.001). The children born SGA were significantly leaner than the reference group. An inverse correlation was found between leptin and chronological age in the SGA group (r = -0.31, P < 0.01). The mean serum level of leptin in the children born SGA who were older than 5.5 years of age was 2.8 micrograms/l which was significantly lower than the mean value of 3.7 micrograms/l found in the children born AGA of the same age range. The difference remained after adjustment of leptin levels for sex, age, body mass index (BMI) and weight-for-height SDS (WHSDSSDS). Leptin correlated with WHSDSSDS (r = 0.32, P < 0.001) and BMI (r = 0.36, P < 0.01) in the reference population, but not in the SGA group. No correlation was found between leptin and spontaneous 24-h GH secretion, insulin-like growth factor (IGF)-I or IGF-binding protein-3 levels, or with fasting insulin or cortisol levels. Leptin levels at the start of GH treatment were correlated with the growth response over both 1 year (r = 0.46, P < 0.001) and 2 years (r = 0.51, P < 0.001) of GH therapy. Using multiple regression analysis, models including leptin levels at the start of GH therapy could explain 51% of the variance in the growth response after 1 year and 44% after 2 years of GH treatment. In conclusion, serum leptin levels are reduced in short children born SGA and are inversely correlated with chronological age. Leptin concentrations correlate with the growth response to GH treatment and might be used as a marker for predicting the growth response to GH treatment.

Leptin levels are strongly correlated with those of GH-binding protein in prepubertal children

OBJECTIVE

Nutritional status is an important determinant of growth, and previous studies have indicated that this is due, at least in part, to an increased target-tissue sensitivity to GH. An attractive candidate for mediating this effect is leptin, a hormone secreted by the adipose tissue. The aim of this study was to investigate if there was a connection between GH-binding protein (GHBP) and leptin.

DESIGN AND METHODS

We investigated the relationship between serum levels of leptin and those of GHBP in 229 prepubertal children. These included 107 healthy children with normal GH secretion, 55 GH-deficient (GHD) children and 55 children born small for gestational age (SGA) sampled on one occasion for GHBP and leptin, and 12 healthy children followed longitudinally at monthly interval for 1 year.

RESULTS

In the healthy children and in those born SGA, the serum concentration of GHBP was positively correlated with that of leptin (r = 0.65, P < 0.001; r = 0.74, P < 0.001 respectively). There was no correlation between GHBP and leptin in the group of children with GHD (r = 0.27, not significant). This means that leptin alone explained 42% of the variation of GHBP in the healthy group and 55% in the SGA group. The correlation remained after adjustment for body mass index and age in the healthy children (r = 0.57, P < 0.0001, r2 = 0.33) and for children born SGA (r = 0.74, P < 0.0001, r2 = 0.55). There was a positive correlation between the intra-individual monthly changes in GHBP and changes in leptin respectively, in the 12 healthy children followed longitudinally, the mean of the correlation coefficients was 0.38 (median = 0.29; range 0.03 to 0.86; P < 0.05).

CONCLUSIONS

There was a highly significant correlation between serum levels of leptin and those of GHBP, except in children with GHD. The possibility that leptin could mediate the effects of body fat mass on GH sensitivity, therefore, merits further investigation.

Growth hormone (GH)-binding protein in prepubertal short children born small for gestational age: effects of growth hormone treatment. Swedish Study Group for Growth Hormone Treatment

This study was undertaken to characterize the serum levels of GH-binding protein (GHBP) before and during GH treatment in prepubertal short children born small for gestational age (SGA) and their relationship with growth parameters. Sixty-seven prepubertal short children (49 boys and 18 girls; height SD score, -5.4 to -2.0; age, 2.0-12.8 yr) born SGA, 8 of whom (6 boys and 2 girls) had signs of Silver-Russell syndrome, participated in the study. Total GHBP was measured by a ligand-mediated immunofunctional assay. The mean (SD) change in height SD score during the year before the start of GH treatment (0.1 IU/kg.day) was 0.11 (0.20) SD score, and this value increased to a 0.84 (0.43) SD score during the first year (P < 0.001) and to a 1.27 (0.63) SD score during the 2-yr period of therapy (P < 0.001). The baseline GHBP values ranged from 49-392 pmol/L, and no relationships were found among sex, chronological age, and maximal GH response to an arginine-insulin tolerance test. A positive correlation between GHBP and body composition, expressed as weight for height SD score, was found in the whole group (r = 0.28; P < 0.05) and in boys (r = 0.44; P < 0.01). No relationship was found between GHBP and spontaneous 24-h GH secretion, in terms of either GH secretion rate or pulsatile pattern, whereas GHBP was positively correlated with insulin-like growth factor I (IGF-I) SD score (r = 0.28; P < 0.05) and IGF-binding protein-3 SD score (r = 0.39; P < 0.01). Using a multiple stepwise linear regression analysis, the model using the IGF-binding protein-3 SD score and the weight for height SD score at the start of GH therapy accounted for 33% of the variance in the baseline GHBP values. A mean increase of 27 (51)% in GHBP levels was found after 1 yr of therapy. However, a high degree of variability in the response of individuals to GH treatment in terms of GHBP levels was observed: in some children GHBP levels increased, whereas in others they decreased. In conclusion, GHBP levels in short prepubertal children born SGA were mostly within the normal range previously reported and correlated directly with body composition. An increase in GHBP levels was observed during GH treatment in some SGA children. No correlation was found between pretreatment GHBP levels and growth response to GH treatment.

Growth hormone status in six children with fetal alcohol syndrome

OBJECTIVE

Prenatal alcohol exposure may cause fetal alcohol syndrome (FAS), which is associated with pre- and postnatal retardation.

MATERIALS AND METHODS

Spontaneous 24-h growth hormone (GH) secretion was measured in six prepubertal short children with FAS (two boys and four girls) aged 4-14 years. The response to a GH stimulation test, and levels of insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 (IGFBP-3) were also measured. Comparisons were made between the children with FAS and healthy children of both normal and short stature, as well as children born small for gestational age (SGA).

RESULTS

There were no differences in the mean area under the curve above the baseline or the maximum level of GH during a 24-h period (GHmax) between the children with FAS and the reference groups. However, the estimated rate of spontaneous 24-h GH secretion in children with FAS was similar to that of children born SGA, but lower than in children of normal stature (p = 0.02). The plasma concentrations of IGF-I and IGFBP-3 were in the lower parts of the normal range.

CONCLUSION

We conclude that GH secretion in short children with FAS is similar to that in short children born SGA; that is, in the lower range of normal children.

Changes in serum insulin-like growth factor I (IGF-I) and IGF-binding protein-3 levels during growth hormone treatment in prepubertal short children born small for gestational age

The aims of this study were to describe the basal serum levels of insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) and to evaluate their changes during daily GH treatment (0.1 IU/kg; 33 micrograms/kg) for up to 2 yr in prepubertal short children born small for gestational age (SGA) and to correlate these changes with the growth response to GH therapy. Seventy-two prepubertal short children (height SD score, -5.4 to -2.0; age, 2.0-12.9 yr) born SGA (54 boys and 18 girls), eight of whom (six boys and two girls) had signs of Silver-Russell syndrome, participated in the study. The serum concentrations of IGF-I and IGFBP-3 were converted into SDS using our reference values for prepubertal healthy children. The mean (+/-SD) change in height SDS during the year before the start of GH treatment was 0.1 (0.2) and increased to 0.8 (0.4) during the first year (P < 0.001) and to 0.6 (0.3) during the second year of therapy (P < 0.001). Basal levels of both IGF-I and IGFBP-3 were significantly reduced compared with the reference values. The mean (+/-SD) basal serum concentration of IGF-I was -0.6 (1.1) SD score, and 80% of the SGA children had IGF-I levels below the 50th percentile of the reference group. The corresponding values for IGFBP-3 were -0.4 (1.0) SD score and 63%. The mean IGF-I level increased significantly by 55% from baseline to day 10 of treatment, by 76% on day 90, by 90% after 1 yr, and by 123% after 2 yr of GH treatment. The mean increases in IGFBP-3 were not as great: 25%, 27%, 35%, and 43%, respectively. The 1-yr growth response, expressed as the change in height SD score, correlated negatively with both the basal serum concentration of IGF-I (r = -0.37; P < 0.001) and IGFBP-3 (r = -0.35; P < 0.01), whereas a positive correlation was found to the 10-day percent increase in IGF-I (r = 0.32; P < 0.05). No correlations were found with the initial changes in IGFBP-3. Using a multiple stepwise linear regression analysis, the model using chronological age at the start of GH therapy, the mother's height expressed as a SD score, and the short term percent increase in IGF-I accounted for 42% of the variance in the 1-yr growth response. With the inclusion of 24-h GH profiles, 59% of the variability of the growth response could be explained. It is concluded that short prepubertal children born SGA show an increased growth rate in response to GH therapy. Their mean IGF-I and IGFBP-3 levels before treatment were low and correlated negatively with the growth response to treatment, indicating GH insufficiency. Finally, up to 59% of the variability in the 1-yr growth response to GH treatment could be explained by models using auxological and biochemical variables.

Spontaneous 24-hour growth hormone profiles in prepubertal small for gestational age children

To evaluate spontaneous GH secretion in terms of both secretory rate and pulsatile pattern in prepubertal children born small for gestational age (SGA) and still short (below -2 SD scores) at or after 2 yr of age, 24-h GH profiles were investigated in 106 such patients (75 boys and 31 girls; mean age, 7.3 +/- 0.3 yr), 14 of whom (10 boys and 4 girls) had Silver-Russell syndrome. The 24-h secretion of GH was compared with that in 2 reference populations of prepubertal children born at an appropriate size for gestational age (AGA): 179 short healthy children (143 boys and 36 girls; mean age, 10.2 +/- 0.2 yr) and 73 children of normal stature (54 boys and 19 girls; mean age, 10.4 +/- 0.3 yr). Plasma GH concentrations from the 24-h profiles were transformed to GH secretion rates by means of a deconvolution technique. For the SGA children, the mean GH secretion rate was 0.3 U/24 h, with a positive correlation with age, whereas for the reference groups it was higher, 0.5 U/24 h for the short children (P < 0.05) and 0.7 U/24 h for the children of normal stature (P < 0.001). Interestingly, the GH secretion rate correlated positively with weight for height, expressed as the SD score, in girls born SGA (r = 0.40; P < 0.05), whereas an inverse correlation was found for the short AGA girls (r = -0.44; P < 0.05). The mean baseline GH level in the SGA children correlated negatively with age (r = -0.53; P < 0.01), with the highest values found for children younger than 6 yr of age. On the average, 8 GH peaks/24-h period were found in all groups of children, and using Fourier time-series analyses, a similar rhythmicity was found in all groups. In the SGA group, the children younger than 6 yr of age had more GH peaks with lower amplitudes than the older children. It is concluded that children born SGA and still short at or after 2 yr of age spontaneously secrete less GH than healthy children of short stature born AGA. Both of these subgroups of prepubertal short children, however, secrete less GH than children of normal height. This finding might in part explain the growth failure in SGA children. Moreover, in the youngest SGA children (2-6 yr of age) there was another pattern of GH secretion, with a high basal GH level, a low peak amplitude, and a high peak frequency.(ABSTRACT TRUNCATED AT 400 WORDS)