What is the evidence for beneficial effects of growth hormone treatment beyond height in short children born small for gestational age? A review of published literature

Potential for Optimization of Growth Hormone Treatment in Children with Growth Hormone Deficiency, Small for Gestational Age, and Turner Syndrome in Germany: Data from the PATRO® Children Study

INTRODUCTION

Growth hormone (GH) treatment in children with growth hormone deficiency (GHD), short children born small for gestational age (SGA), and Turner syndrome (TS) is well established. However, a variety of parameters are still under discussion to achieve optimal growth results and efficiency of GH use in real-world treatment.

METHODS

German GH-treatment naïve patients of the PATRO Children database were grouped according to their start of treatment into groups of 3 years from 2007 to 2018. Time trends in age, gender, GH dose, height standard deviation score (SDS), first-year growth response, and Index of Responsiveness (IoR) were investigated in children with GHD, short children born SGA, and TS starting GH treatment in the German patient population of the PATRO Children database from 2007 to 2018 to determine specific parameters for GH treatment optimization.

RESULTS

All patient groups started GH treatment at a relatively high chronological age (2007-2009: GHD 8.33 ± 3.19, SGA 7.32 ± 2.52, TS 8.65 ± 4.39) with a slight but not significant trend towards younger therapy start up to 2016-2018 (GHD 8.04 ± 3.36, SGA 6.67 ± 2.65, TS 7.85 ± 3.38). In the GHD and SGA groups, female patients were underrepresented compared to male patients (GHD 32.3%, SGA 43.6%) with no significant change over the 4 time periods. Patients with GHD started GH treatment at a low dose (0.026 mg/kg/day). In SGA and TS patients, GH therapy was started below the registered dose recommendation (30.0 μg/kg/day and 33.7 μg/kg/day, respectively). In the first year of treatment, the mean GH dose was increased moderately (GHD: 30.7, SGA: 35.7, TS: 40.8 μg/kg/day). There was no significant change of GH dosing over time from 2007 to 2018. The IoR was comparable between time-groups for all 3 diagnoses.

DISCUSSION

This study shows potential for improvement of GH treatment results in GHD, SGA, and TS patients in terms of early dose adjustment and younger age at the start of treatment. This is in accordance with important parameters used in prediction models.

Growth trajectory of full-term small-for-gestational-age infants: a 3-year longitudinal study in China

OBJECTIVE

Small-for-gestational-age (SGA) infants are at risk of impaired growth and developmental outcomes, even for those who were born at full term. The growth trajectory of full-term SGA infants remains unknown. Therefore, this study aimed to evaluate the growth trajectory of full-term SGA infants from birth to 3 years old in East China.

METHODS

Full-term SGA infants were followed up from birth to 3 years old. The weight and length were measured at 3, 6, 12, 18, 24, 30 and 36 months. Rate of catch-up growth and rates of growth deviations including short stature, emaciation, underweight, overweight and obesity, were calculated at different time points. Latent class analysis was applied to describe growth trajectories from birth to 36 months.

RESULTS

A total of 816 full-term SGA infants were enrolled in this study and 303 had complete follow-up data at 3, 6, 12, 18, 24, 30 and 36 months. At 24 months, the rate of catch-up growth was 42.4% in girls and 48.6% in boys; while at 36 months, this rate was 43.3% in girls and 52.1% in boys. The latent class analysis identified two trajectories of weight and length in boys and girls. Girls showed different growth trajectories of weight since 12 months compared with boys.

CONCLUSIONS

Our study reported a relatively low rate of catch-up growth in full-term SGA infants and has identified different growth trajectories of length and weight in boys and girls. We call for attention from health professionals on the growth trajectory of full-term SGA infants to eventually promote their health potentials.

Effect of treatment with growth hormone on body composition and metabolic profile of short children born small for gestational age

OBJECTIVE

To assess the effect of recombinant growth hormone (rGH) on body composition and metabolic profile of prepubertal short children born small for gestational age (SGA) before and after 18 months of treatment.

METHODS

It is a clinical, non-randomized, and paired study. Children born SGA, with birth weight and/or length <-2 standard deviations (SD) for gestational age and sex, prepubertal, born at full term, of both genders, with the indication for treatment with rGH were included. The intervention was performed with biosynthetic rGH at doses ranging from 0.03 to 0.05 mg/kg/day, administered subcutaneously, once a day at bedtime. Total lean mass (LM) and total fat mass (FM) were carried out using dual-energy X-ray absorptiometry (DXA), and the metabolic profile was assessed for insulin, glycemia, IGF-1 levels and lipid profile.

RESULTS

Twelve patients (nine girls, 8.17±2.39 y) were evaluated; three patients dropped out of the study. There was an increase of LM adjusted for length (LMI) (p=0.008), LMI standard deviation score (SDS) adjusted for age and sex (p=0.007), and total LM (p<0.001). The percentage of body fat (BF%) and abdominal fat (AF) remained unaltered in relation to the beginning of treatment. Among the metabolic variables, blood glucose remained within normal levels, and there was a reduction in the number of participants with altered cholesterol (p=0.023).

CONCLUSIONS

The effect of rGH treatment was higher on LM than in FM, with increased LM adjusted for length and standardized for age and sex. Glycemia remained within the normal limits, and there was a decreased number of children with total cholesterol above the recommended levels.

Lipid Profile in Children Born Small for Gestational Age

BACKGROUND

Lipid disorders are one of the risk factors for cardiovascular diseases. The aim of the study was to estimate the lipid profile in early childhood in the population of Polish children born small for gestational age (SGA).

MATERIALS AND METHODS

The study included 140 patients (93 SGA children and 47 controls) aged 5 to 11 years. All the subjects underwent a physical examination and blood laboratory tests for the glucose and lipid profiles. The SGA group was divided into subgroups, i.e., symmetrical and asymmetrical intrauterine growth restriction (IUGR).

RESULTS

Blood sample analysis revealed higher levels of total cholesterol (SGA group 190.61 ± 24.66 mg/dL vs. controls 143.23 ± 23.90; p < 0.001). The analysis of particular cholesterol fractions showed significantly higher mean values of triglycerides and LDL cholesterol as well as lower mean values of HDL cholesterol in SGA children. Children in both groups did not differ significantly in terms of weight or body mass index. A statistically significantly higher glucose concentration was observed in SGA patients with the symmetrical type of IUGR. Analyzing the differences regarding metabolic factors, we obtained a statistically significant difference only in fasting glucose concentration (asymmetrical IUGR = 90.56 ± 10.21 vs. symmetrical IUGR = 98.95 ± 14.79; p < 0.001).

CONCLUSIONS

Children born SGA, even those not suffering from overweight or obesity in their early childhood, have an abnormal lipid profile, which may contribute to the development of cardiovascular diseases in adulthood.

Longitudinal assessment of bone health index as a measure of bone health in short-statured children before and during treatment with recombinant growth hormone

OBJECTIVES

The aim of our study was the longitudinal assessment of bone health index (BHI) in short-statured children during growth hormone (GH) treatment to estimate changes in their bone health.

METHODS

256 short-statured children (isolated GH deficiency (IGHD) n=121, multiple pituitary hormone deficiency (MPHD) n=49, intrauterine growth retardation (small for gestational age (SGA)) n=52, SHOX (short stature homeobox gene) deficiency n=9, Ullrich Turner syndrome (UTS) n=25) who started with GH between 2010 and 2018 were included. Annual bone ages (Greulich and Pyle, GP) and BHI were, retrospectively, analysed in consecutive radiographs of the left hand (BoneXpert software) from GH therapy start (T0) up to 10 years (T10) thereafter, with T max indicating the individual time point of the last available radiograph. The results are presented as the median (25 %/75 % interquartile ranges, IQR) and statistical analyses were performed using non-parametric tests as appropriate.

RESULTS

The BHI standard deviation scores (SDS) were reduced (-0.97, -1.8/-0.3) as bone ages were retarded (-1.6 years, -2.31/-0.97) in all patients before start of GH and were significantly lower in patients with growth hormone deficiency (GHD) (-1.04, -1.85/-0.56; n=170) compared to non-GHD patients (-0.79, -1.56/-0.01; n=86; p=0.022). BHI SDS increased to -0.17 (-1/0.58) after 1 year of GH (T1, 0.5-1.49, p<0.001) and to -0.20 (-1/-0.50, p<0.001) after 5.3 years (T max, 3.45/7.25).

CONCLUSIONS

BHI SDS are reduced in treatment-naive short-statured children regardless of their GH status, increase initially with GH treatment while plateauing thereafter, suggesting sustained improved bone health.

The Association of Accelerated Early Growth, Timing of Puberty, and Metabolic Consequences in Children

Accelerated early growth and early timing of puberty or pubertal variant have been noticed as risk factors for metabolic syndrome, more frequently observed in children born small for gestational age (SGA) or children with premature adrenarche (PA). Children with SGA, especially if they make an accelerated catch-up growth in early life, carry a higher risk for long-term metabolic consequences, such as type 2 diabetes, insulin resistance, and cardiovascular diseases. Furthermore, multiple studies support that these children, either born SGA or with a history of PA, may have earlier pubertal timing, which is also associated with various metabolic risks. This review aims to summarize the recent studies investigating the association between early infantile growth, the timing of puberty, and metabolic risks to expand our knowledge and gain more insight into the underlying pathophysiology.

The long-term growth, cost-effectiveness, and glycemic effects of growth hormone therapy on children born small for gestational age over 10 years: a retrospective cohort study

OBJECTIVES

We aimed to report our 10-year experience of treating short children born small for gestational age (SGA) by comparing the long-term growth, metabolic safety, and cost-effectiveness of recombinant human growth hormone (rhGH) therapy in short children born SGA with those in rhGH-treated children with growth hormone deficiency (GHD) and Turner syndrome.

METHODS

We performed a 10-year retrospective cohort study at King Saud University Medical City. We included children aged 3-16 years who received rhGH for GHD, SGA, or Turner syndrome for >1 year.

RESULTS

A total of 166 children received rhGH therapy for GHD, 58 for SGA, and 16 for Turner syndrome. During the last study visit, the average height change was 21 cm for GHD children and 14 cm for children born SGA (p-value <0.001). The height SDS change was 0.84 for GHD children and 0.55 for SGA children (p-value=0.004). The average cost-effectiveness ratios for treating GHD and SGA children were USD 1,717.22 and USD 1,157.19 per centimeter gained, respectively. Moreover, the mean incremental cost-effectiveness ratio for GHD vs. SGA patients was USD 2,820.39 per centimeter gained. Dysglycemia developed in 70 patients: 43 (36.44%), 22 (40.74%), and 5 (13%) in the GHD, SGA, and Turner syndrome groups, respectively.

CONCLUSIONS

rhGH is effective in height improvement of short children. However, pursuing rhGH treatment for children born SGA requires a shared decision-making approach to balance the modest benefit of final adult height gain with the long-term metabolic effects, considering the acceptable costs on the Saudi healthcare system.

Growth hormone treatment does not to lead to insulin resistance nor excessive rise in IGF-1 levels, while improving height in patients small for gestational age A long-term observational study

OBJECTIVE

In children born small for gestational age (SGA), the relationship between growth hormone (GH) treatment and insulin resistance (IR) has only been investigated for a short period, necessitating a longer observation period. This study aimed to evaluate the long-term (10 years) effect of GH to SGA-children on IR and safety during treatment.

DESIGN

This was a multicenter observational study.

PATIENTS

SGA-children who received GH treatment in Spain (stratified by Tanner-stage and age at GH onset [two groups: ≤6 years old or >6 years old]).

MEASUREMENTS

The analysed variables (yearly measures) included auxologic, metabolic (insulin-like growth factor-1 (IGF-1), height velocity [HV], weight and homeostatic model assessment-IR [HOMA-IR]) and safety data. Data were collected prospectively (since the study approval: 2007) and retrospectively (since the initiation of GH treatment: 2005-2007).

RESULTS

A total of 389 SGA children (369 Tanner-I) were recruited from 27 centres. The mean age (standard deviation) of the children at GH treatment onset was 7.2 (2.8) years old. IGF-1 (standard deviation score [SDS]) and HOMA-IR values tended to increase until the sixth year of GH-treatment, with significant differences being observed only during the first year, while these remained stable in the later years (within normal ranges). Height (SDS) increased significantly (basal: -3.0; tenth year: -1.13), and the maximum HV (SDS) occurred during the first year (2.75 ± 2.39).

CONCLUSIONS

HOMA-IR values increased significantly in SGA-children during the first year of GH-treatment, remained stable and were within normal ranges in all cases. Our 10-year data suggests that long-term GH treatment does not promote IR and is well-tolerated, safe and effective.

Approach to the Patient: Safety of Growth Hormone Replacement in Children and Adolescents

The use of recombinant human growth hormone (rhGH) in children and adolescents has expanded since its initial approval to treat patients with severe GH deficiency (GHD) in 1985. rhGH is now approved to treat several conditions associated with poor growth and short stature. Recent studies have raised concerns that treatment during childhood may affect morbidity and mortality in adulthood, with specific controversies over cancer risk and cerebrovascular events. We will review 3 common referrals to a pediatric endocrinology clinic, followed by a summary of short- and long-term effects of rhGH beyond height outcomes. Methods to mitigate risk will be reviewed. Finally, this information will be applied to each clinical case, highlighting differences in counseling and clinical outcomes. rhGH therapy has been used for more than 3 decades. Data are largely reassuring, yet we still have much to learn about pharmaceutical approaches to growth in children and the lifelong effect of treatment.

Integrated Digital Health Solutions in the Management of Growth Disorders in Pediatric Patients Receiving Growth Hormone Therapy: A Retrospective Analysis

Digital health has seen rapid advancements over the last few years in helping patients and their healthcare professionals better manage treatment for a variety of illnesses, including growth hormone (GH) therapy for growth disorders in children and adolescents. For children and adolescents requiring such therapy, as well as for their parents, the treatment is longitudinal and often involves daily injections plus close progress monitoring; a sometimes daunting task when young children are involved. Here, we describe our experience in offering devices and digital health tools to support GH therapy across some 40 countries. We also discuss how this ecosystem of care has evolved over the years based on learnings and advances in technology. Finally, we offer a glimpse of future planned enhancements and directions for digital health to play a bigger role in better managing conditions treated with GH therapy, as well as model development for adherence prediction. The continued aim of these technologies is to improve clinical decision making and support for GH-treated patients, leading to better outcomes.

The association between growth patterns and blood pressure in children and adolescents: A cross-sectional study of seven provinces in China

Aimed to investigate the associations between different growth patterns with high blood pressure, and further examine the mediation effect of BMI between growth patterns and high blood pressure among children and adolescents. A total of 31581 children and adolescents aged 7–18 years were selected based on the stratified cluster sampling method. Logistics regression models were used to calculate the odds rations (ORs) and 95% confidence interval (95%CI) of the association between different growth patterns and high blood pressure. Mediation effect analyses were applied to estimate the effect of BMI on the increase of blood pressure levels in different growth patterns. In different sex and ages, compared to reference group of normal growth, blood pressure levels and prevalence of high blood pressure of the catch‐up growth were higher, but that of the catch‐down growth were lower. The prevalence of high blood pressure was 11.69%, 16.06%, and 9.68% in normal growth, catch‐up growth, and catch‐down growth, respectively. In total, compared with the normal growth pattern, the ORs (95%CI) of high blood pressure, high systolic blood pressure and high diastolic blood pressure in the catch‐up growth were 1.171(1.073,1.280), 1.110(1.001,1.230) and 1.141(1.025,1.270) (p < .05), respectively. Additionally, the mediation effect of current BMI existed in the association between blood pressure levels and different growth patterns, particularly in boys. Our findings suggested that different growth patterns after birth could modify blood pressure, and the potential risks of high blood pressure could be increased by catch‐up growth at childhood and adolescence.

Catch-Up Growth in Children Born Small for Gestational Age Related to Body Composition and Metabolic Risk at Six Years of Age in the UK

OBJECTIVES

To determine differences in body composition and glucose metabolism according to childhood growth outcomes in a population-based sample of children born small for gestational age (SGA).

METHODS

A single-centre study of 259 children born SGA identified through hospital records and contacted when aged 4-7 years. Questionnaire data on pre/perinatal history and growth parameters during childhood was collected from the parents, and in a subgroup of 150 children face-to-face assessments were performed, including anthropometric parameters, lean and fat mass, blood pressure, fasting glucose, and C-peptide.

RESULTS

Based on the questionnaires, few children had formal clinic follow-up of growth, but 7% of the cohort showed a height and weight of <-2SDS during childhood, and only 2 children met the criteria for growth hormone therapy. Out of the 150 children assessed at a mean age of 6.1 ± 0.8 years, 122 (81%) showed a catch-up growth in weight. Compared to those without weight catch-up, these children had a higher fat mass index (3.13 ± 1.36 vs. 2.56 ± 0.91 kg/m2, p = 0.04), trunk-to-limb fat mass ratio (0.63 ± 0.14 vs. 0.56 ± 0.08, p = 0.002), systolic blood pressure SDS (0.09 ± 0.71 vs. -0.32 ± 0.63, p = 0.008), fasting glucose (4.5 ± 0.5 vs. 4.3 ± 0.5 mmol/L, p = 0.03), and C-peptide (306 ± 116 vs. 256 ± 112 pmol/L, p = 0.08). Among children with weight catch-up growth, those with less height gain had a lower limb lean mass index (4.25 ± 0.48 vs. 4.48 ± 0.56 kg/m2, p = 0.02) and fat mass index (1.57 ± 0.59 vs. 1.83 ± 0.77 kg/m2, p = 0.04).

CONCLUSIONS

Within this population-based sample of SGA children, catch-up growth in weight was associated with higher abdominal fat mass, blood pressure and glycemia; furthermore, in these children, less height gain was associated with reduced limb lean and fat mass.

An eHealth Framework for Managing Pediatric Growth Disorders and Growth Hormone Therapy

Background

The use of technology to support health and health care has grown rapidly in the last decade across all ages and medical specialties. Newly developed eHealth tools are being implemented in long-term management of growth failure in children, a low prevalence pediatric endocrine disorder.

Objective

Our objective was to create a framework that can guide future implementation and research on the use of eHealth tools to support patients with growth disorders who require growth hormone therapy.

Methods

A total of 12 pediatric endocrinologists with experience in eHealth, from a wide geographical distribution, participated in a series of online discussions. We summarized the discussions of 3 workshops, conducted during 2020, on the use of eHealth in the management of growth disorders, which were structured to provide insights on existing challenges, opportunities, and solutions for the implementation of eHealth tools across the patient journey, from referral to the end of pediatric therapy.

Results

A total of 815 responses were collected from 2 questionnaire-based activities covering referral and diagnosis of growth disorders, and subsequent growth hormone therapy stages of the patient pathway, relating to physicians, nurses, and patients, parents, or caregivers. We mapped the feedback from those discussions into a framework that we developed as a guide to integration of eHealth tools across the patient journey. Responses focused on improved clinical management, such as growth monitoring and automation of referral for early detection of growth disorders, which could trigger rapid evaluation and diagnosis. Patient support included the use of eHealth for enhanced patient and caregiver communication, better access to educational opportunities, and enhanced medical and psychological support during growth hormone therapy management. Given the potential availability of patient data from connected devices, artificial intelligence can be used to predict adherence and personalize patient support. Providing evidence to demonstrate the value and utility of eHealth tools will ensure that these tools are widely accepted, trusted, and used in clinical practice, but implementation issues (eg, adaptation to specific clinical settings) must be addressed.

Conclusions

The use of eHealth in growth hormone therapy has major potential to improve the management of growth disorders along the patient journey. Combining objective clinical information and patient adherence data is vital in supporting decision-making and the development of new eHealth tools. Involvement of clinicians and patients in the process of integrating such technologies into clinical practice is essential for implementation and developing evidence that eHealth tools can provide value across the patient pathway.

New Horizons in Short Children Born Small for Gestational Age

Children born small for gestational age (SGA) comprise a heterogeneous group due to the varied nature of the cause. Approximately 85-90% have catch-up growth within the first 4 postnatal years, while the remainder remain short. In later life, children born SGA have an increased risk to develop metabolic abnormalities, including visceral adiposity, insulin resistance, and cardiovascular problems, and may have impaired pubertal onset and growth. The third "360° European Meeting on Growth and Endocrine Disorders" in Rome, Italy, in February 2018, funded by Merck KGaA, Germany, included a session that examined aspects of short children born SGA, with three presentations followed by a discussion period, on which this report is based. Children born SGA who remain short are eligible for GH treatment, which is an approved indication. GH treatment increases linear growth and can also improve some metabolic abnormalities. After stopping GH at near-adult height, metabolic parameters normalize, but pharmacological effects on lean body mass and fat mass are lost; continued monitoring of body composition and metabolic changes may be necessary. Guidelines have been published on diagnosis and management of children with Silver-Russell syndrome, who comprise a specific group of those born SGA; these children rarely have catch-up growth and GH treatment initiation as early as possible is recommended. Early and moderate pubertal growth spurt can occur in children born SGA, including those with Silver-Russell syndrome, and reduce adult height. Treatments that delay puberty, specifically metformin and gonadotropin releasing hormone analogs in combination with GH, have been proposed, but are used off-label, currently lack replication of data, and require further studies of efficacy and safety.

Neonatal Problems and Infancy Growth of Term SGA Infants: Does "SGA" Definition Need to Be Re-evaluated?

Introduction: The exact definition of small-for-gestational-age (SGA) infant is still controversial among clinicians. In this study, we aimed to understand which definition is better in terms of establishing both early postnatal problems and growth. In this way, we compared early neonatal problems and infancy growth of term infants with birth weight (BW) < -2 SDS and with BW between 10th percentile (-1.28 SDS) and -2 SDS. Methods: A single center retrospective cohort study was conducted. Preterm infants, multiple gestations and newborns with any congenital anomalies were excluded from the study. Study group was defined as Group 1 (n = 37), infants BW < -2.00 SDS; Group 2 (n = 129), between -1.28 and -2.00 SDS; and Group 3 (n = 137), randomly selected newborns with optimal-for-gestational-age (BW between -0.67 and +0.67 SDS) as a control group. Results: The incidence of severe hypoglycemia was highest in Group 1 (%10.8) and Group 2 and 3 had similar rates of severe hypoglycemia (0.8 and 0.7%, respectively). The incidence of polycythemia was 5.4% in Group 1 and was significantly higher than Group 3 (0.0%) while it was 2.3% in Group 2. Short stature (length < -2 SDS) ratio at the age of 1 and 2 years were similar in each group. Overweight/obesity ratio at the age of 1 were 9.5, 20.8 and 16.7% in each group, respectively (p = 0.509). Conclusion: This study was planned as a pilot study to determine potential differences in the problems of hypoglycemia, polycythemia, and growth according to the differences in definition. Short term disturbances such as hypoglycemia and polycythemia are found to be higher in infants with a BW SDS below -2. From this point of view, of course, it will not be possible to change the routine applications immediately, however this study will be an initiative for discussions by making long-term studies.