Search

Approximately 15 million babies are born preterm across the world every year, with less than 37 completed weeks of gestation. Survival rates increased during the last decades with the improvement of neonatal care. With premature birth, babies are deprived of the intense intrauterine growth phase, and postnatal growth failure might occur. Some children born prematurely will remain short at later ages and adult life. The risk of short stature increases if the child is also born small for gestational age. In this review, the effects of being born preterm on childhood growth and adult height and the hormonal abnormalities possibly associated with growth restriction are discussed, followed by a review of current information on growth hormone treatment for those who remain with short stature during infancy and childhood., (© 2017 European Society of Endocrinology.)

Background: Short children born small for gestational age (SGA) are treated with a GH dose based on body size, but treatment may lead to high levels of IGF1. The objective was to evaluate IGF1 titration of GH dose in contrast to current dosing strategies., Methods: In the North European Small-for-Gestational-Age Study (NESGAS), 92 short pre-pubertal children born SGA were randomised after 1 year of high-dose GH treatment (67 μg/kg per day) to three different regimens: high dose (67 μg/kg per day), low dose (35 μg/kg per day) or IGF1 titration., Results: The average dose during the second year of the randomised trial did not differ between the IGF1 titration group (38 μg/kg per day, s.d. 0.019) and the low-dose group (35 μg/kg per day, s.d. 0.002; P=0.46), but there was a wide variation in the IGF1 titration group (range 10-80 μg/kg per day). The IGF1 titration group had significantly lower height gain (0.17 SDS, s.d. 0.18) during the second year of the randomised trial compared with the high-dose group (0.46 SDS, s.d. 0.25), but not significantly lower than the low-dose group (0.23 SDS, s.d. 0.15; P=0.17). The IGF1 titration group had lower IGF1 levels after 2 years of the trial (mean 1.16, s.d. 1.24) compared with both the low-dose (mean 1.76, s.d. 1.48) and the high-dose (mean 2.97, s.d. 1.63) groups., Conclusion: IGF1 titration of GH dose in SGA children proved less effective than current dosing strategies. IGF1 titration resulted in physiological IGF1 levels with a wide range of GH dose and a poorer growth response, which indicates the role of IGF1 resistance and highlights the heterogeneity of short SGA children., (© 2014 European Society of Endocrinology.)

Background: The etiology of prenatal-onset short stature with postnatal persistence is heterogeneous. Submicroscopic chromosomal imbalances, known as copy number variants (CNVs), may play a role in growth disorders., Objective: To analyze the CNVs present in a group of patients born small for gestational age (SGA) without a known cause., Patients and Methods: A total of 51 patients with prenatal and postnatal growth retardation associated with dysmorphic features and/or developmental delay, but without criteria for the diagnosis of known syndromes, were selected. Array-based comparative genomic hybridization was performed using DNA obtained from all patients. The pathogenicity of CNVs was assessed by considering the following criteria: inheritance; gene content; overlap with genomic coordinates for a known genomic imbalance syndrome; and overlap with CNVs previously identified in other patients with prenatal-onset short stature., Results: In 17 of the 51 patients, 18 CNVs were identified. None of these imbalances has been reported in healthy individuals. Nine CNVs, found in eight patients (16%), were categorized as pathogenic or probably pathogenic. Deletions found in three patients overlapped with known microdeletion syndromes (4q, 10q26, and 22q11.2). These imbalances are de novo, gene rich and affect several candidate genes or genomic regions that may be involved in the mechanisms of growth regulation., Conclusion: Pathogenic CNVs in the selected patients born SGA were common (at least 16%), showing that rare CNVs are probably among the genetic causes of short stature in SGA patients and revealing genomic regions possibly implicated in this condition., (© 2014 European Society of Endocrinology.)

Objective: The aims of this study was to determine whether prepubertal GH deficiency (GHD) children showed any impairment in coagulation- and fibrinolysis-related parameters and in inflammatory and insulin resistance markers and to evaluate the effect of short-term GH therapy on these parameters., Design: This was a 6-month, prospective, observational, case-control study (36 prepubertal children with GHD and 38 healthy prepubertal children with no differences in BMI). Comparison of study parameter values in GHD AND control groups at baseline and after 6 months of GH treatment in the GHD group. The following were analyzed: glucose, insulin, fibrinogen, absolute plasminogen activator inhibitor type 1 (aPAI-1), von Willebrand factor (vWF), homeostasis model assessment for insulin resistance (HOMA-IR) index, C-reactive protein (CRP), and interleukin 6 (IL6) levels., Results: Children with GHD showed higher baseline levels of aPAI-1 and fibrinogen and lower levels of glucose, insulin, and HOMA-IR index than healthy controls. No intergroup differences were found for vWF. After 6 months of treatment, aPAI-1 levels were lower but no changes were observed in fibrinogen or vWF levels, which were similar to those of controls. Glucose levels increased, though not significantly, while insulin levels and HOMA-IR index rose to normal levels. A positive correlation was found between changes in insulin status/HOMA-IR index and levels of aPAI-1, fibrinogen, vWF, CRP, and IL6., Conclusions: At early ages, GH therapy appears to exert beneficial effects on the amount of aPAI-1. At the same time, it increases the state of insulin resistance (HOMA-IR index) without modifying the levels of fibrinogen, vWF, CRP, and IL6.

Objective: We examined the association of active ghrelin levels with birth weight, sex, and gestational age (GA) in small for GA (SGA) and appropriate for GA (AGA) preterm infants., Methods: Active ghrelin levels were measured by ELISA method during the first five postnatal days in 38 preterm SGA infants and 32 preterm AGA controls., Results: Active ghrelin levels were significantly higher in preterm SGA infants than in preterm AGA controls (P < 0.01). Active ghrelin levels in preterms with birth weight <1500 g were statistically higher than those over 1500 g. Active ghrelin levels in preterms ≤ 34 gestational weeks were similar to those over 34 weeks. A negative correlation was detected between active ghrelin levels and birth weight (r = -0.561, P < 0.0001) as well as GA (r = -0.449, P < 0.0001)., Conclusion: We found significantly higher active ghrelin levels in SGA preterms than those in AGA preterms and demonstrated a negative correlation between active ghrelin levels and birth weight in preterm infants. This was the first study showing a negative correlation between active ghrelin levels and birth weight in preterm infants.

Objective: Smaller size at birth has been associated with an increased risk of metabolic and cardiovascular disorders in adult life. Fetal programming of the hypothalamic-pituitary-adrenal axis has been suggested as a possible explanation. Fetal glucocorticoid (GC) overexposure has effects that suggest a role of GCs in this programming. The effects of GCs are mediated through the GC receptor (GR or NR3C1). Several functional polymorphisms have been described, which are associated with relative GC resistance or hypersensitivity. Our aim is to compare frequencies of GR haplotypes, characterized by the R23K, N363S, Bcl1, or 9β polymorphisms, in subjects born small for gestational age (SGA) and associate birth anthropometry data, response to GH treatment, blood pressure, glucose and insulin concentrations, and body composition with these haplotypes., Design: In total, 418 SGA subjects and 697 healthy controls were enrolled in this study. Methods Anthropometry data were obtained, as well as blood samples to determine fasting glucose and insulin concentrations. Dual energy X-ray absorptiometry scans were used to measure the amount of fat and lean mass., Results: No differences were found between GR haplotype frequencies in SGA children compared with healthy controls. No associations were found between GR haplotypes and birth length and birth weight, growth response during GH treatment, blood pressure, glucose and insulin concentrations, and body composition., Conclusion: GR haplotypes and their effect on GC sensitivity do not seem to play a significant role in GH-induced catch-up growth and the risk factors of developing metabolic and cardiovascular disorders in adult life of SGA children.

Context: Short children born small for gestational age (SGA) have a lean phenotype with lower insulin sensitivity and higher blood pressure. GH treatment results in weight gain, and a decrease in blood pressure and insulin sensitivity. However, not all children respond in the same way. The Pro12Ala polymorphism of the peroxisome proliferator-activated receptor (PPAR-gamma) gene is inversely associated with body mass index (BMI), changes in BMI and the risk to develop type 2 diabetes mellitus., Objective: To analyze the contribution of the PPAR-gamma Pro12Ala polymorphism to GH induced changes in determinants of metabolic and cardiovascular disease in short SGA children., Methods: PPAR-gamma was genotyped in 238 Caucasian short SGA children (mean age 7.5 years). Height, weight, blood pressure, and serum lipids were measured before start and during 4 years of GH treatment. In addition, glucose homeostasis by homeostasis model assessment insulin resistance ratio (HOMA-IR) (n=148) and by frequently sampled i.v. glucose tolerance test (n=51), and body composition by dual energy X-ray absorptiometry (n=79) were measured., Results: At baseline, the Ala12 allele was not associated with any determinant of metabolic and cardiovascular disease. After 4 years of GH treatment, the increase in weight for height SDS and BMI SDS was significantly greater in carriers of an Ala12 allele than in noncarriers. The change in all other parameters was not associated with Pro12Ala genotype., Conclusion: The Ala12 variant of the PPAR-gamma gene is associated with higher weight gain during GH treatment but not with changes in determinants of metabolic and cardiovascular diseases in Caucasian subjects born SGA.

Objective: Height variability is largely under genetic control, although identifying the genetic variants involved has been until recently challenging. Smallness for gestational age (SGA) is a risk factor for adult short stature. Genome-wide association studies have identified a single nucleotide polymorphism (SNP) (rs1042725) in the high mobility group A2 gene (HMGA2) that consistently associates with height variability but its interaction with SGA is unknown., Design: We assess the contribution of rs1042725 SNP and height variability in a French population and the impact of rs1042725 on SGA status at birth and height at adulthood in SGA individuals., Methods: We genotyped rs1042725 in 4710 healthy participants from the Data from an Epidemiological Study on the Insulin Resistance syndrome (DESIR) cohort, 743 normal birth weight and 660 SGA individuals from the Haguenau study., Results: rs1042725 is associated with increased height in the cohort participants (0.36 cm 95% CI (0.12-0.61) per C allele, P=0.004) but not with the SGA status or birth length. Interestingly, rs1042725 had a stronger effect on height in SGA participants (0.94 cm 95% CI (0.24-1.64) per C allele, P=0.009), especially in men (1.45 cm 95% CI (0.44-2.46) per C allele, P=0.005) in whom rs1042725 may explain 3% of height variability. SGA men carrying at least one C allele copy experienced more frequent catch-up in height (P(add)=0.07; P(dom)=0.03)., Conclusions: Our study supports further the contribution of HMGA2 rs1042725 to height variability in European populations and shows an increased effect on height in SGA individuals where this variant favors height catch-up.

Background: Ghrelin, the natural ligand of the GH secretagogue receptor, has potent orexigenic effect. Ghrelin levels are negatively associated with insulin secretion, increased in anorexia, and reduced in obesity. Increased ghrelin levels may be associated with early postnatal growth in preterm born children., Objective: Aim of this study was to evaluate ghrelin and insulin levels at prepubertal ages in preterm born children born appropriate for gestational age (AGA) or small for gestational age (SGA) and relationships with catch-up growth (CUG) in a prospective cross-sectional study., Methods: Eighty-four preterm born children grouped as preterm SGA (n=28) and preterm AGA (n=56) were evaluated at age 4.7+/-0.2 and 4.7+/-0.1 years with respect to their ghrelin and insulin levels. Their data were compared with that of body mass index matched term SGA (n=35) and term AGA (n=44) children of age 4.6+/-0.2 and 3.8+/-0.1 years. All children had height appropriate for their target height. CUG was defined as the difference between birth size and recent size and expressed as Delta height and Delta weight SDS., Results: Preterm SGA and preterm AGA children had similar ghrelin levels (1717.0+/-166.9 and 1656.5+/-103.8 pg/ml), although Delta height and Delta weight SDS in preterm SGA were significantly higher than in preterm AGA children (P<0.001). Ghrelin levels in both preterm groups were higher than term SGA (469.2+/-132.5 pg/ml) and term AGA children (659.6+/-143.3 pg/ml; P<0.001 for all). Delta Height and Delta weight SDS of the term SGA children were similar to that of preterm SGA children. Ghrelin did not have correlation with CUG but had inverse correlation with recent anthropometric indices. Insulin was significantly higher in term SGA children than other groups (P<0.001)., Conclusions: Preterm children have higher ghrelin levels at prepubertal ages regardless of the magnitude of their CUG. Term SGA children, on the other hand, behave differently and have lower ghrelin levels than preterm children at prepubertal ages, which may be related to elevated insulin levels in this group.

Background: Fetal growth restriction (FGR) has been related to several health risks, which have been generally identified in small-for-gestational age (SGA) individuals., Objective: To evaluate the impact of FGR on body composition and hormonal status in infants born either small- or appropriate-for-gestational age (AGA)., Methods: Fetal growth was assessed by ultrasound every 4 weeks from mid-gestation to birth in 248 high-risk pregnancies for SGA. Fetal growth velocity was calculated as change in the estimated fetal weight percentiles and FGR defined as its reduction by more than 20 percentiles from 22 gestational weeks to birth. Impact of FGR on body composition, cord insulin, IGF-I, IGF binding protein-3 (IGFBP-3), and cortisol concentrations was assessed in SGA and AGA newborns., Results: Growth-retarded AGA infants showed significantly reduced birth weight, ponderal index, percentage of fat mass, and bone mineral density when compared with AGA newborns with stable intrauterine growth. Cord IGF-I and IGFBP-3 concentrations were significantly decreased in growth-retarded infants in both SGA and AGA groups. Cord insulin concentration was significantly lower and cord cortisol significantly higher in AGA infants with FGR versus AGA newborns with stable intrauterine growth. After adjustment for gestational age and gender, birth weight was directly related to fetal growth velocity and cord IGF-I concentration. The variation in infant's adiposity was best explained by fetal growth velocity and cord insulin concentration., Conclusions: FGR affects body composition and hormonal parameters in newborns with birth weight within the normal range, suggesting these individuals could be at similar metabolic risks as SGA. .

Fetal growth retardation is associated with decreased postnatal growth, resulting in a lower adult height. In addition, a low birth weight is associated with an increased risk of developing diseases during adulthood, such as insulin resistance, type 2 diabetes mellitus, hypertension, dyslipidemia, and cardiovascular diseases. Children with persistent postnatal growth retardation, i.e., incomplete catch-up growth, can be treated with human GH. The GH/IGF-I axis is involved in the regulation of carbohydrate and lipid metabolism. The question of whether treatment with GH in children born small for gestational age (SGA) has long-term implications with respect to glucose/insulin and lipid metabolism has not been answered yet. In this article, the available data are reviewed.

Objective: Human GH (hGH) treatment leads to catch-up growth in children with short stature born small for gestational age (SGA). However, long-term efficacy and safety results in this patient group remain scarce. The present study assessed the efficacy and safety of late childhood treatment with biosynthetic hGH (Humatrope) in a group of short children born SGA (height <-2 standard deviation scores (SDS))., Design: Patients in this open-label, Phase III, multicenter study received a daily hGH dose of 0.067 mg/kg for 2 years, and then received no treatment for the following 2 years. After the fourth year on study, patients whose height had decreased more than 0.5 SDS but who still showed growth potential based on bone age were allowed to resume treatment until they reached adult height., Methods: Height gain SDS was assessed for 11 girls and 24 boys (mean age+/-s.d. 9.6+/-0.9 years) at the end of the 2 years of hGH treatment, during the subsequent 2-year off-treatment period, and upon reaching adult height., Results: At the end of the initial 2-year treatment period, 83% of patients had reached a height within the normal range, with a mean increase in height SDS vs baseline of 1.3+/-0.3 (P <0.001). Adult heights (n = 20) were within the normal range for 50% of patients, and mean height gain from baseline was statistically significant (0.7+/-0.8 SDS, P <0.001). Fasting glucose and glycosylated hemoglobin levels were not significantly modified during treatment., Conclusions: High-dose hGH treatment for a minimum of 2 years in short children born SGA was well tolerated and resulted in a significant increase in adolescent and adult height.

Adolescent growth represents 15-20% of adult height and has been the focus of several treatment interventions, aiming at increasing the amplitude of the adolescent spurt. Importantly, pre- and early puberty are times when patients and families seek medical help and when estimates of adult height are more accurate than in younger children. We review the current approaches aimed at increasing pubertal growth in short children and knowledge about their results and risks. GnRH agonists, when used outside the context of precocious puberty, induce a modest gain (4 cm) when they are used for more than 3 years. Their effects on bone mass, body composition and possibly on psychosocial parameters limit their use. Several trials have now shown that GH can increase adult height of short adolescents with idiopathic short stature or born small for gestational age. However, the amplitude of the effect is modest and of dubious clinical significance. Lastly, the association of both approaches is rather popular among pediatric endocrinologists but still lacks a definite demonstration of its efficacy. In conclusion, we have gained insight in the median effects of some of these treatments and overoptimistic initial expectations are now refocused. However, we still have a long way to go before we truly evaluate the factors affecting the variable individual responses to these treatments, their clinical significance and their cost-benefit balance.