Cardiovascular risk factors and carotid intima media thickness in young adults born small for gestational age after cessation of growth hormone treatment: a 5-year longitudinal study

Cerebral white matter hyperintensities in adults born small for gestational age at 12 years after cessation of childhood growth hormone treatment: a prospective cohort study including untreated controls

Background

Increased cerebrovascular morbidity was reported in adults born small for gestational age (SGA) who were treated with growth hormone (GH) during childhood compared to the general population. Yet, previous studies lacked an appropriate control group which is a major limitation. We prospectively studied cerebral white matter hyperintensities (WMHs) in adults born SGA at 12 years after cessation of childhood GH-treatment (SGA-GH), compared to appropriate controls.

Methods

In this prospective cohort study, performed between May 2016 and December 2020, total WMHs, periventricular WMHs (PVWMHs) and deep WMHs (DWMHs) were the primary outcomes of the study, they were qualitatively assessed using 3 Tesla (T) Magnetic Resonance Imaging (MRI) and scored using the Fazekas scale in SGA-GH adults and in 3 untreated control groups: adults born SGA with persistent short stature (SGA-S), adults born SGA with spontaneous catch-up growth to a normal height (SGA-CU) and adults born appropriate for gestational age with a normal height (AGA). Regression analyses were performed in the total cohort to evaluate the associations of GH-treatment and birth characteristics with WMHs.

Findings

297 adults were investigated (91 SGA-GH, 206 controls). Prevalence of total WMHs was 53.8% (95% CI 43.1-64.3) in SGA-GH, 40.5% (95% CI 25.6-56.7) in SGA-S, 73.9% (95% CI 61.9-83.7) in SGA-CU and 41.1% (95% CI 31.1-51.6) in AGA adults. No statistically significant differences in total WMHs, PVWMHs and DWMHs were found between SGA-GH compared to SGA-S and AGA adults. Highest prevalence of all type of WMHs was found in SGA-CU adults compared to all groups. Higher prevalence of total WMHs was associated with lower birth weight standard deviation score (SDS), but not with GH-treatment.

Interpretation

Our findings suggest that GH-treatment in children born SGA has no negative impact on the prevalence of all type of WMHs at 12 years after GH cessation compared to appropriate controls. SGA-CU adults had the highest prevalence of all type of WMHs around age 30 years.

Funding

Novo Nordisk.

Growth hormone in pediatric chronic kidney disease: more than just height

Recombinant human growth hormone therapy, which was introduced in the 1980s, is now routine for children with advanced chronic kidney disease (CKD) who are exhibiting growth impairment. Growth hormone usage remains variable across different centers, with some showing low uptake. Much of the focus on growth hormone supplementation has been on increasing height because of social and psychological effects of short stature. There are, however, numerous other changes that occur in CKD that have not received as much attention but are biologically important for pediatric growth and development. This article reviews the current knowledge about the multisystem effects of growth hormone therapy in pediatric patients with CKD and highlights areas where additional clinical research is needed. We also included clinical data on children and adults who had received growth hormone for other indications apart from CKD. Ultimately, having robust clinical studies which examine these effects will allow children and their families to make more informed decisions about this therapy.

Cerebrovascular Abnormalities in Adults Born SGA at 12 Years After Growth Hormone Cessation Compared to Controls

CONTEXT

Increased cerebrovascular morbidity was reported in adults born small for gestational age (SGA) who were treated with growth hormone (GH) during childhood compared to the general population. However, previous studies did not have an appropriate control group, which is a major limitation.

OBJECTIVE

To study cerebrovascular abnormalities (aneurysms, previous intracerebral hemorrhages and microbleeds) using magnetic resonance imaging (MRI) in adults born SGA at 12 years after cessation of childhood GH treatment (SGA-GH) compared to appropriate controls.

METHODS

In this single-center, prospective study, brain MRIs were performed between May 2016 and December 2020 on a 3T MRI system. MRI images were scored by 2 neuroradiologists who were blinded to patient groupings. Participants included adults born SGA previously treated with GH and 3 untreated control groups: adults born SGA with persistent short stature (SGA-S), adults born SGA with spontaneous catch-up growth to a normal height (SGA-CU) and adults born appropriate for gestational age with a normal height (AGA). The intervention was long-term GH treatment during childhood and the main outcome measure was cerebrovascular abnormalities.

RESULTS

A total of 301 adults were investigated. Aneurysms were found in 6 adults: 3 (3.6%) SGA-GH, 1 (2.9%) SGA-S and 2 (2.2%) AGA adults, without differences between SGA-GH adults and the controls. Previous intracerebral hemorrhages were only found in 2 SGA-S adults (4.8%). Microbleeds were found in 17 adults: 4 (4.3%) SGA-GH, 4 (9.5%) SGA-S, 3 (4.3%) SGA-CU and 6 (6.3%) AGA adults, without differences between SGA-GH adults and the controls.

CONCLUSION

Our findings suggest that SGA-GH adults at 12 years after GH cessation have no increased prevalence of cerebrovascular abnormalities compared to appropriate controls. Further research is needed to confirm our findings.

Long-Term Efficacy and Safety of Recombinant Human Growth Hormone in Children Born Small for Gestational Age

There is a lack of long-term data on the benefit of growth hormone (GH) treatment in Chinese children born small for gestational age (SGA). This study was conducted to assess the long-term efficacy and safety of GH treatment in children born SGA. One hundred and twenty prepubertal SGA children who did not achieve catch-up growth with height remained less than -2 standard deviations (SD) below gender-specific height were enrolled in this two-year, randomized, dose-comparative study followed by an extension study of up to 10 years. Daily subcutaneous injections of 0.23 mg/kg/week [low-dose (LD) group] or 0.46 mg/kg/week [high-dose (HD) group] somatropin were given for 104 weeks. Dosing in the extension study was≤0.46 mg/kg/week. The main outcome measures were change in height SD score (ΔHT-SDS), height velocity, insulin-like growth factor (IGF)-1, and IGF-1/IGF binding protein-3 (IGFBP-3) molar ratio. ΔHT-SDS at week 104 was 0.91±0.53 and 1.52±0.64 in the LD and HD groups (intergroup p<0.0001), respectively, and continued in an upward trend throughout the extension study, remaining above+2 for those who received treatment for a total of 7 years or more. At week 104, significant improvements were observed in height velocity, IGF-1 SDS, and IGF-1/IGFBP-3 molar ratio. Adult HT-SDS was -0.81±1.68 for boys and -0.82±1.05 for girls (p=0.9837). Glucose metabolism and thyroid function were within the normal reference range throughout treatment. Long-term recombinant human GH treatment was tolerable and effective at improving height in children born SGA.

International Consensus Guideline on Small for Gestational Age (SGA): Etiology and Management from Infancy to Early Adulthood

This International Consensus Guideline was developed by experts in the field of SGA of 10 pediatric endocrine societies worldwide. A consensus meeting was held and 1300 articles formed the basis for discussions. All experts voted about the strengths of the recommendations. The guideline gives new and clinically relevant insights into the etiology of short stature after SGA birth, including novel knowledge about (epi)genetic causes. Besides, it presents long-term consequences of SGA birth and new treatment options, including treatment with gonadotropin-releasing hormone agonist (GnRHa) in addition to growth hormone (GH) treatment, and the metabolic and cardiovascular health of young adults born SGA after cessation of childhood-GH-treatment in comparison with appropriate control groups. To diagnose SGA, accurate anthropometry and use of national growth charts are recommended. Follow-up in early life is warranted and neurodevelopment evaluation in those at risk. Excessive postnatal weight gain should be avoided, as this is associated with an unfavorable cardio-metabolic health profile in adulthood. Children born SGA with persistent short stature < -2.5 SDS at age 2 years or < -2 SDS at age of 3-4 years, should be referred for diagnostic work-up. In case of dysmorphic features, major malformations, microcephaly, developmental delay, intellectual disability and/or signs of skeletal dysplasia, genetic testing should be considered. Treatment with 0.033-0.067 mg GH/kg/day is recommended in case of persistent short stature at age of 3-4 years. Adding GnRHa treatment could be considered when short adult height is expected at pubertal onset. All young adults born SGA require counseling to adopt a healthy lifestyle.

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.

Highlighting the trajectory from intrauterine growth restriction to future obesity

During the last decades several lines of evidence reported the association of an adverse intrauterine environment, leading to intrauterine restriction, with future disease, such as obesity and metabolic syndrome, both leading to increased cardiovascular and cancer risk. The underlying explanation for this association has firstly been expressed by the Barker's hypothesis, the "thrifty phenotype hypothesis". According to this hypothesis, a fetus facing an adverse intrauterine environment adapts to this environment through a reprogramming of its endocrine-metabolic status, during the crucial window of developmental plasticity to save energy for survival, providing less energy and nutrients to the organs that are not essential for survival. This theory evolved to the concept of the developmental origin of health and disease (DOHaD). Thus, in the setting of an adverse, f. ex. protein restricted intrauterine environment, while the energy is mainly directed to the brain, the peripheral organs, f.ex. the muscles and the liver undergo an adaptation that is expressed through insulin resistance. The adaptation at the hepatic level predisposes to future dyslipidemia, the modifications at the vascular level to endothelial damage and future hypertension and, overall, through the insulin resistance to the development of metabolic syndrome. All these adaptations are suggested to take place through epigenetic modifications of the expression of genes without change of their amino-acid sequence. The epigenetic modifications leading to future obesity and cardiovascular risk are thought to induce appetite dysregulation, promoting food intake and adipogenesis, facilitating obesity development. The epigenetic modifications may even persist into the next generation even though the subsequent generation has not been exposed to an adverse intrauterine environment, a notion defined as the "transgenerational transfer of environmental information". As a consequence, if the increased public health burden and costs of non-communicable chronic diseases such as obesity, hypertension, metabolic syndrome and type 2 diabetes have to be minimized, special attention should be laid to the healthy lifestyle habits of women of reproductive age, including healthy diet and physical activity to be established long before any pregnancy takes place in order to provide the best conditions for both somatic and mental health of future generations.

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.

Association of Childhood Growth Hormone Treatment With Long-term Cardiovascular Morbidity

IMPORTANCE

Concerns about the cardiovascular safety of recombinant human growth hormone (rhGH) treatment in childhood have recently been raised; however, long-term studies are limited.

OBJECTIVE

To investigate the long-term risk of overall and severe cardiovascular events in patients previously treated with rhGH in childhood and whether there is an association with treatment duration or dose.

DESIGN, SETTING, AND PARTICIPANTS

This nationwide population-based cohort study included patients treated with rhGH during childhood from January 1, 1985, to December 31, 2010, in Sweden, with follow-up through December 31, 2014. Included patients were treated with rhGH owing to isolated growth hormone deficiency (GHD), small for gestational age (SGA), and idiopathic short stature (ISS). For each patient, 15 age-, sex-, and region-based matched control individuals were randomly selected from the general population as a comparison group. Data on cardiovascular outcomes and covariates including gestational age, birth weight, birth length, socioeconomic status, and height were obtained through linkage with several health care and population-based registers. Data were analyzed from January 1, 1985, to December 31, 2014.

EXPOSURES

Treatment with rhGH during childhood and adolescence (aged 0-18 years).

MAIN OUTCOMES AND MEASURES

The primary outcome was the first cardiovascular event recorded after the start of follow-up, and the secondary outcome was the first severe cardiovascular event.

RESULTS

A total of 53 444 individuals (3408 patients and 50 036 controls; 67.7% men; mean [SD] age at study end, 25.1 [8.2] years) were followed up for as long as 25 years (median follow-up, 14.9 [range, 0-25] years; total, 795 125 person-years). Among 1809 recorded cardiovascular events, the crude incidence rates were 25.6 events per 10 000 person-years for patients and 22.6 events per 10 000 person-years for controls. The adjusted hazard ratio (HR) for all cardiovascular events was higher in patients compared with controls (HR, 1.69; 95% CI, 1.30-2.19), especially for women (HR, 2.05; 95% CI, 1.31-3.20) compared with men (HR, 1.55; 95% CI, 1.12-2.13). All subgroups had increased HRs (SGA, 1.97 [95% CI, 1.28-3.04]; GHD, 1.66 [95% CI, 1.21-2.26]; and ISS, 1.55 [95% CI, 1.01-2.37]). Longer duration of rhGH treatment (HR, 2.08; 95% CI, 1.35-3.20) and total cumulative dose (HR, 2.05; 95% CI, 1.18-3.55) were associated with higher risk for overall cardiovascular disease. The adjusted HR for severe cardiovascular disease was 2.27 (95% CI, 1.01-5.12).

CONCLUSIONS AND RELEVANCE

In this cohort study, treatment with rhGH during childhood due to GHD, SGA, or ISS was associated with increased risks of cardiovascular events in early adulthood, particularly in women; however, conclusions of causality are still limited and the absolute risk remains low.

Longitudinal Study on Metabolic Health in Adults SGA During 5 Years After GH With or Without 2 Years of GnRHa Treatment

BACKGROUND

In children born small for gestational age (SGA) with persistent short stature, 2 years of gonadotropin-releasing hormone analogue (GnRHa), in addition to long-term growth hormone (GH) treatment, can improve adult height. We assessed safety on metabolic and bone health of GnRHa/GH treatment during 5 years after cessation of GH.

METHODS

A total of 363 young adults born SGA, previously treated with combined GnRHa/GH or GH-only, were followed for 5 years after attainment of adult height at GH cessation and 2 and 5 years thereafter. Data at 5 years after GH cessation, at age 21 years, were also compared with 145 age-matched adults born appropriate for gestational age (AGA). Frequently sampled intravenous glucose tolerance (FSIGT) tests were used to assess insulin sensitivity, acute insulin response, and β-cell function. Body composition and bone mineral density (BMD) was determined by dual-energy x-ray absorptiometry (DXA) scans.

FINDINGS

In the GnRHa/GH and GH-only groups, fat mass increased during the 5 years after GH cessation, but the changes in FSIGT results, body composition, blood pressure, serum lipid levels, and BMD were similar in both groups. At age 21 years, the GnRHa/GH group had similar fat mass, FSIGT results, blood pressure, serum lipid levels and BMD-total body as the GH-only group and the AGA control group, a higher BMD-lumbar spine and lower lean body mass than the AGA control group.

INTERPRETATION

This study during 5 years after GH cessation shows that addition of 2 years of GnRHa treatment to long-term GH treatment of children short in stature born SGA has no unfavorable effects on metabolic and bone health in early adulthood.

CLINICAL TRIAL REGISTRATION

ISRCTN96883876, ISRCTN65230311 and ISRCTN18062389.

Glomerular filtration rate, blood pressure and microalbuminuria in adults born SGA: A 5-year longitudinal study after cessation of GH treatment

BACKGROUND

Growth hormone treatment increases glomerular filtration rate (GFR), as serum IGF-I stimulates the renin-angiotensin system. Infants born with a low birth weight have a smaller number of nephrons, which cause a lower GFR, a higher blood pressure and a higher albumin-to-creatinine ratio in early adulthood.

METHOD

A total of 261 young adults born SGA, previously treated with growth hormone (SGA-GH), were longitudinally followed. Glomerular filtration rate, based on serum creatinine levels, was determined at cessation of GH treatment and at 6 months, 2 years and 5 years thereafter. Glomerular filtration rate, blood pressure and urinary albumin-to-creatinine ratio at 5 years after cessation of GH were compared with untreated age-matched controls (56 untreated short subjects born SGA [SGA-S], 118 subjects born SGA with spontaneous catch-up growth [SGA-CU], 135 subjects born appropriate for gestational age [AGA]).

RESULTS

Glomerular filtration rate decreased significantly only during the first 6 months after cessation of GH treatment, while remaining well within the normal range (124.6 vs 120.2 mL/min/1.73 m² , P < .001). SGA-GH adults had a similar GFR, blood pressure and urinary albumin-to-creatinine ratio as the healthy controls born SGA and AGA.

CONCLUSION

In conclusion, our 5 years longitudinal follow-up study shows a decrease in GFR during 6 months after GH cessation, but thereafter GFR remained stable and within the normal range. Glomerular filtration rate, blood pressure and urinary albumin-to-creatinine ratio at 21 years of age were similar in GH-treated young adults born SGA and untreated controls born SGA or AGA. We conclude that long-term GH treatment in children born SGA has no unfavourable effects on kidney function in early adulthood. PRÉCIS: We present a longitudinal study on kidney function in the follow-up of growth hormone-treated young adults who were born small for gestational age.

Children Born Small for Gestational Age: Differential Diagnosis, Molecular Genetic Evaluation, and Implications

Children born small for gestational age (SGA), defined as a birth weight and/or length below -2 SD score (SDS), comprise a heterogeneous group. The causes of SGA are multifactorial and include maternal lifestyle and obstetric factors, placental dysfunction, and numerous fetal (epi)genetic abnormalities. Short-term consequences of SGA include increased risks of hypothermia, polycythemia, and hypoglycemia. Although most SGA infants show catch-up growth by 2 years of age, ∼10% remain short. Short children born SGA are amenable to GH treatment, which increases their adult height by on average 1.25 SD. Add-on treatment with a gonadotropin-releasing hormone agonist may be considered in early pubertal children with an expected adult height below -2.5 SDS. A small birth size increases the risk of later neurodevelopmental problems and cardiometabolic diseases. GH treatment does not pose an additional risk.