Seven years of growth hormone (GH) replacement improves quality of life in hypopituitary patients with adult-onset GH deficiency

Clinical Management of Postoperative Growth Hormone Deficiency in Hypothalamic-Pituitary Tumors

The present review focuses on growth hormone (GH) deficiency in pediatric and adult patients following surgery for hypothalamic-pituitary tumors, with a special emphasis on hormone replacement therapy with recombinant human growth hormone (rhGH). The symptoms and metabolic changes associated with GH deficiency are reviewed, and the potential risks and therapeutic outcomes of rhGH treatment in these patients are discussed. This review emphasizes the importance of rhGH in the normalization of growth in children and the improvement of quality of life (QoL) and metabolic health in adults. Aspects related to efficacy, safety, dosage, duration of treatment, and QoL in this population are analyzed. The need for regular follow-up and dose adjustment to maintain the optimal IGF-I levels in these patients is emphasized, as is the importance of individualized assessment and collaboration with a specialized multidisciplinary medical team to make the appropriate therapeutic decisions. Furthermore, continuous follow-up are necessary to optimize the clinical outcomes in this patient population.

Approach to the Patient: Case Studies in Pediatric Growth Hormone Deficiency and Their Management

CONTEXT

Pathologies attributed to perturbations of the GH/IGF-I axis are among the most common referrals received by pediatric endocrinologists.

AIM

In this article, distinctive cased-based presentations are used to provide a practical and pragmatic approach to the management of pediatric growth hormone deficiency (GHD).

CASES

We present 4 case vignettes based on actual patients that illustrate (1) congenital GHD, (2) childhood GHD presenting as failure to thrive, (3) childhood GHD presenting in adolescence as growth deceleration, and (4) childhood-onset GHD manifesting as metabolic complications in adolescence. We review patient presentation and a management approach that aims to highlight diagnostic considerations for treatment based on current clinical guidelines, with mention of new therapeutic and diagnostic modalities being used in the field.

CONCLUSION

Pediatric GHD is diverse in etiology and clinical presentation. Timely management has the potential not only to improve growth but can also ameliorate or even mitigate adverse metabolic outcomes, which can be directly attributed to a GH deficient state.

Metabolic and quality of life effects of growth hormone replacement in patients with TBI and AGHD: A pilot study

OBJECTIVE

Traumatic brain injury (TBI), a common cause of adult growth hormone deficiency (AGHD), affects 20% of Veterans returning from Iraq and Afghanistan (OEF/OIF/OND). Growth hormone replacement therapy (GHRT) improves quality of life (QoL) in AGHD but remains unexplored in this population. This pilot, observational study investigates the feasibility and efficacy of GHRT in AGHD following TBI.

DESIGN

In this 6-month study of combat Veterans with AGHD and TBI starting GHRT (N = 7), feasibility (completion rate and rhGH adherence) and efficacy (improvements in self-reported QoL) of GHRT were measured (primary outcomes). Secondary outcomes included body composition, physical and cognitive function, psychological and somatic symptoms, physical activity, IGF-1 levels and safety parameters. It was hypothesized that participants would adhere to GHRT and that QoL would significantly improve after six months.

RESULTS

Five subjects (71%) completed all study visits. All patients administered daily rhGH injections, 6 (86%) of whom consistently administered the clinically-prescribed dose. While QoL demonstrated numeric improvement, this change did not reach statistical significance (p = 0.17). Significant improvements were observed in total lean mass (p = 0.02), latissimus dorsi strength (p = 0.05), verbal learning (Trial 1, p = 0.02; Trial 5, p = 0.03), attention (p = 0.02), short-term memory (p = 0.04), and post-traumatic stress disorder (PTSD) symptoms (p = 0.03). Body weight (p = 0.02) and total fat mass (p = 0.03) increased significantly.

CONCLUSION

GHRT is a feasible and well-tolerated intervention for U.S. Veterans with TBI-related AGHD. It improved key areas impacted by AGHD and symptoms of PTSD. Larger, placebo-controlled studies testing the efficacy and safety of this intervention in this population are warranted.

Effects of 18 months of GH replacement on cardiovascular risk factors and quality of life in GH deficient adults; a randomized controlled trial using a fixed very low and a standard dose of GH

OBJECTIVE

Little is known of the effects of a fixed very low dose of growth hormone (GH) replacement on cardiovascular risk factors, bone mass, muscle strength and quality of life (QoL) in hypopituitary patients.

DESIGN/PATIENTS/METHODS

This was an open-label randomized study performed at a single center. Consecutive hypopituitary patients with adult onset GH deficiency (GHD) and BMI ≥ 27 kg/m² were randomized to receive a very low fixed dose of GH (LG, n = 9) or a standard dose of GH (SG, n = 9). Body composition, glucose and lipid metabolism, bone mineral content (BMC) and density (BMD), muscle strength, and QoL were measured at baseline and after 6, 12 and 18 months.

RESULTS

The fixed GH dose in LG was 0.1 mg/day. In SG, the mean baseline GH dose of 0.13 mg/day was gradually increased to 0.31 mg/day at study end. Lean body mass (LBM) as measured using DEXA as well as total body water (TBW) and extracellular water (ECW) were increased only in SG (P < 0.01, P < 0.05, and P < 0.01 vs. LG, respectively). There were no between-groups differences in BMD, BMC, insulin sensitivity, lipids, or muscle strength. Finally, although not significant compared with SG, a sustained improvement in QoL was seen in LG according to the QoL-AGHDA questionnaire.

CONCLUSION

In this pilot study, a fixed very low GH dose improved QoL in GHD adults without any induction of fluid retention. Other effects were comparable to those produced by the standard GH dose. Replacement with a very low GH dose could therefore be a treatment option in hypopituitary patients, especially in patients who do not tolerate higher GH dosage. Trial registration This study is registered at ClinicalTrials.gov, EU-nr 2009-016783-37.

Quality of Life in Craniopharyngioma: A Systematic Review

BACKGROUND

Craniopharyngiomas are morbid tumors that significantly reduce patients' quality of life (QoL). The lifelong burden of endocrine, visual, hypothalamic, and limbic dysfunction can have disastrous consequences for the physical and psychosocial health of patients. Elucidating the factors that influence QoL could guide therapeutic interventions to improve patient well-being.

METHODS

A systematic review was performed in accordance with the PRISMA (preferred reporting items for systematic reviews and meta-analyses) statement using the PubMed and Medline databases. Studies that had reported patient QoL using validated metrics in both adult and pediatric populations were included. Bias and methodological rigor were assessed using the MINORS (methodological index for nonrandomized studies) criteria.

RESULTS

A total of 25 studies, including 2025 patients, were available for review. Most studies were small, retrospective, cohort studies with a high risk of bias. The QoL of the patients with craniopharyngioma was lower than that of the general population. Hypothalamic involvement was consistently the strongest predictor of QoL. Endocrinopathy contributed to morbidity but could be ameliorated by hormone replacement therapy. Social and emotional dysregulation and a poor memory are common complaints after surgery, and iatrogenic damage to the infundibulum, hypothalamus, limbic system, and frontal lobes might underlie these concerns. Sleep-wake cycle dysfunction and hypothalamic obesity are serious consequences of hypothalamic damage.

CONCLUSIONS

An experienced multidisciplinary team is necessary to optimally manage the complex cases of these patients. The poor QoL of patients with craniopharyngioma is multifactorial. However, the contribution of iatrogenesis is not insubstantial. Improved surgical techniques, focusing on hypothalamic preservation, and adjuvant treatment options are required to improve the well-being of these patients.

Metabolomics as a potential tool for the diagnosis of growth hormone deficiency (GHD): a review

Metabolomics uses several analytical tools to identify the chemical diversity of metabolites present in organisms. These metabolites are low molecular weight molecules (<1500 Da) classified as a final or intermediary product of metabolic processes. The application of this omics technology has become prominent in inferring physiological conditions through reporting on the phenotypic state; therefore, the introduction of metabolomics into clinical studies has been growing in recent years due to its efficiency in discriminating pathophysiological states. Regarding endocrine diseases, there is a great interest in verifying comprehensive and individualized physiological scenarios, in particular for growth hormone deficiency (GHD). The current GHD diagnostic tests are laborious and invasive and there is no exam with ideal reproducibility and sensitivity for diagnosis neither standard GH cut-off point. Therefore, this review was focussed on articles that applied metabolomics in the search for new biomarkers for GHD. The present work shows that the applications of metabolomics in GHD are still limited, since the little complementarily of analytical techniques, a low number of samples, GHD combined to other deficiencies, and idiopathic diagnosis shows a lack of progress. The results of the research are relevant and similar; however, their results do not provide an application for clinical practice due to the lack of multidisciplinary actions that would be needed to mediate the translation of the knowledge produced in the laboratory, if transferred to the medical setting.

Growth Hormone (GH) Enhances Endogenous Mechanisms of Neuroprotection and Neuroplasticity after Oxygen and Glucose Deprivation Injury (OGD) and Reoxygenation (OGD/R) in Chicken Hippocampal Cell Cultures

As a classical growth promoter and metabolic regulator, growth hormone (GH) is involved in development of the central nervous system (CNS). This hormone might also act as a neurotrophin, since GH is able to induce neuroprotection, neurite growth, and synaptogenesis during the repair process that occurs in response to neural injury. After an ischemic insult, the neural tissue activates endogenous neuroprotective mechanisms regulated by local neurotrophins that promote tissue recovery. In this work, we investigated the neuroprotective effects of GH in cultured hippocampal neurons exposed to hypoxia-ischemia injury and further reoxygenation. Hippocampal cell cultures obtained from chick embryos were incubated under oxygen-glucose deprivation (OGD, <5% O₂, 1 g/L glucose) conditions for 24 h and simultaneously treated with GH. Then, cells were either collected for analysis or submitted to reoxygenation and normal glucose incubation conditions (OGD/R) for another 24 h, in the presence of GH. Results showed that OGD injury significantly reduced cell survival, the number of cells, dendritic length, and number of neurites, whereas OGD/R stage restored most of those adverse effects. Also, OGD/R increased the mRNA expression of several synaptogenic markers (i.e., NRXN1, NRXN3, NLG1, and GAP43), as well as the growth hormone receptor (GHR). The expression of BDNF, IGF-1, and BMP4 mRNAs was augmented in response to OGD injury, and exposure to OGD/R returned it to normoxic control levels, while the expression of NT-3 increased in both conditions. The addition of GH (10 nM) to hippocampal cultures during OGD reduced apoptosis and induced a significant increase in cell survival, number of cells, and doublecortin immunoreactivity (DCX-IR), above that observed in the OGD/R stage. GH treatment also protected dendrites and neurites during OGD, inducing plastic changes reflected in an increase and complexity of their outgrowths during OGD/R. Furthermore, GH increased the expression of NRXN1, NRXN3, NLG1, and GAP43 after OGD injury. GH also increased the BDNF expression after OGD, but reduced it after OGD/R. Conversely, BMP4 was upregulated by GH after OGD/R. Overall, these results indicate that GH protective actions in the neural tissue may be explained by a synergic combination between its own effect and that of other local neurotrophins regulated by autocrine/paracrine mechanisms, which together accelerate the recovery of tissue damaged by hypoxia-ischemia.

Safety and effectiveness of replacement with biosimilar growth hormone in adults with growth hormone deficiency: results from an international, post-marketing surveillance study (PATRO Adults)

PURPOSE

To evaluate safety and effectiveness of biosimilar recombinant human growth hormone (rhGH; Omnitrope®) in adults with growth hormone deficiency (GHD), using data from the PATRO Adults study.

METHODS

PATRO Adults was a post-marketing surveillance study conducted in hospitals and specialized endocrinology units across Europe. The primary objective was to assess the safety of rhGH in adults treated in routine clinical practice. All adverse events (AEs) were monitored and recorded for the complete duration of Omnitrope® treatment. Effectiveness was evaluated as a secondary objective.

RESULTS

As of January 2020, 1447 patients (50.9% male) had been enrolled from 82 centers in 9 European countries. Most patients had adult-onset GHD (n = 1179; 81.5%); 721 (49.8%) were rhGH-naïve at study entry. Overall, 1056 patients (73.0%) reported adverse events (AEs; n = 5397 events); the majority were mild-to-moderate in intensity. Treatment-related AEs were reported in 117 patients (8.1%; n = 189 events); the most commonly reported (MedDRA preferred terms) were arthralgia (n = 19), myalgia (n = 16), headache (n = 14), and edema peripheral (n = 10). In total, 495 patients (34.2%) had serious AEs (SAEs; n = 1131 events); these were considered treatment-related in 28 patients (1.9%; n = 35 events). Mean (standard deviation) IGF-I SDS increased from - 2.34 (1.47) at baseline to - 0.23 (1.65) at 12 months, and remained relatively stable thereafter (up to 3 years). Body mass index remained stable between baseline and 3 years.

CONCLUSION

Data from PATRO Adults indicate biosimilar rhGH (Omnitrope^®) is not associated with any unexpected safety signals, and is effective in adults with GHD treated in real-world clinical practice.

GH Replacement in the Elderly: Is It Worth It?

Growth hormone (GH), once the age of linear growth is completed, continues to play a fundamental role for the human body. In adulthood, GH contributes to regulate muscle, cardiovascular and bone metabolism. The same happens in old age, although there is less data on the effect of GH in the elderly. Regardless the age of onset, a reduced quality of life (QoL), an increased cardiovascular risk and an accelerated age-related decline in physical strength have been demonstrated in the elderly with GH deficiency (EGHD). In adults with GH deficiency (AGHD), recent studies suggest a role of GH replacement therapy (GHrt) in improving lean/fat mass ratio, blood pressure, lipid profile, bone metabolism and QoL. Despite these recent studies, there is still a lack of randomized controlled trials proving these positive effects in EGHD. Moreover, the lack of a long-term positive outcome on mortality, and the cost of GHrt could often impact on treatment decision-making and lead to postpone or avoid the prescription. The aim of this mini-review is to summarize the available data on GHrt in EGHD, in order to highlight its weaknesses and strengths and to provide directions to clinicians that will help in the management of this specific set of patients.

Motivation for and adherence to growth hormone replacement therapy in adults with hypopituitarism: the patients' perspective

INTRODUCTION

While reasons for non-adherence in children requiring growth hormone (GH) replacement (GH-Rx) are well researched, few studies have investigated adherence in adult GH deficient patients. Against the background of the adverse medical sequelae of untreated severe GH deficiency (GHD) in adults, we explored adherence to GH-Rx and associated factors in this patient group.

METHOD

Cross-sectional analysis including 107 adult patients with severe GHD on GH-Rx, 15 untreated GDH patients and 19 who had discontinued therapy. Patients completed self-developed ad hoc surveys on adherence to medication and GH-Rx, specific beliefs about GH-Rx, side effects and burden of injection, reasons for never receiving or dropping out of therapy, respectively.

RESULTS

Adherence to GH-Rx was high (mean 15.8/18 points on the self-developed adherence score) and significantly correlated with general medication adherence. Higher age was significantly associated with better adherence to GH-Rx, while injection side effects, duration of treatment or device used were not. The most frequent reasons for not being on GH-Rx apart from medical reasons included fear of side effects, lack of belief in treatment effects and dislike of injections. In patients not on GH-Rx, the proportion of patients in employment was significantly smaller than in the treatment group, despite similar age and comorbidities.

CONCLUSIONS

Adherence to GH-Rx was high for those patients on therapy. Instead of focusing on improving adherence in those adults already on GH-Rx, efforts should be undertaken to ally fear of side effects and provide education on positive treatment effects for those eligible but not receiving therapy.

Growth hormone (GH) and synaptogenesis

Growth hormone (GH) is known to exert several roles during development and function of the nervous system. Initially, GH was exclusively considered a pituitary hormone that regulates body growth and metabolism, but now its alternative extrapituitary production and pleiotropic functions are widely accepted. Through excess and deficit models, the critical role of GH in nervous system development and adult brain function has been extensively demonstrated. Moreover, neurotrophic actions of GH in neural tissues include pro-survival effects, neuroprotection, axonal growth, synaptogenesis, neurogenesis and neuroregeneration. The positive effects of GH upon memory, behavior, mood, sensorimotor function and quality of life, clearly implicate a beneficial action in synaptic physiology. Experimental and clinical evidence about GH actions in synaptic function modulation, protection and restoration are revised in this chapter.

Growth hormone therapy in adults with growth hormone deficiency: a critical assessment of the literature

PURPOSE

Growth hormone (GH) therapy has been studied as treatment for clinical manifestations of adult-onset growth hormone deficiency (AO-GHD), including cardiovascular risk, bone health, and quality of life. Patients with AO-GHD typically also have significant history of pituitary pathology and hypopituitarism, which raises the question of what proportion of their clinical presentation can be attributed to GHD alone. Currently, much of the existing data for GH therapy in AO-GHD come from uncontrolled retrospective studies and observational protocols. These considerations require careful reassessment of the role of GH as a therapeutic agent in adult patients with hypopituitarism.

METHODS

We contrast results from placebo-controlled trials with those from uncontrolled and retrospective studies for GH replacement in patients with hypopituitarism. We also examine the evidence for the manifestations of AO-GHD being attributed to GHD alone, as well as the data on adults with congenital, life-long untreated isolated GHD.

RESULTS

The evidence for increased morbidity and mortality in hypopituitary patients with GHD, and for the benefits of GH therapy, are conflicting. There remains the possibility that the described clinical manifestations of AO-GHD may not be due to GHD alone, but may also be related to underlying pituitary pathology, treatment history and suboptimal hormone replacement.

CONCLUSIONS

In the setting of inconsistent data on the benefits of GH therapy, treatment of AO-GHD remains an individualized decision. There is a need for more randomized, placebo-controlled studies to evaluate the long-term outcomes of GH therapy in adults with hypopituitarism.

Growth Hormone Alters Brain Morphometry, Connectivity, and Behavior in Subjects with Fatigue after Mild Traumatic Brain Injury

Pituitary dysfunction with reduced growth hormone (GH) secretion is common in patients following traumatic brain injury (TBI), and these patients often develop chronic symptoms including fatigue and altered cognition. We examined 18 subjects with a history of mild TBI, fatigue, and insufficient GH secretion. Subjects received GH replacement in a year-long, double-blind, placebo-controlled, crossover study, and were assessed for changes in physical performance, body composition, resting energy expenditure, fatigue, sleep, mood, and neuropsychological status. Additionally, magnetic resonance imaging (MRI) was used to assess changes in brain structure and resting state functional connectivity. GH replacement resulted in decreased fatigue, sleep disturbance, and anxiety, as well as increased resting energy expenditure, improved body composition, and altered perception of submaximal effort when performing exercise testing. Associated brain changes included increased frontal cortical thickness and gray matter volume and resting state connectivity changes in regions associated with somatosensory networks. GH replacement altered brain morphology and connectivity and reduced fatigue and related symptoms in mild TBI patients. Additional studies are needed to understand the mechanisms causing TBI-related fatigue and symptom relief with GH replacement.

Growth hormone increases dendritic spine density in primary hippocampal cell cultures

OBJECTIVE

Growth hormone (GH) is widely known for its peripheral effects during growth and development. However, numerous reports also suggest that GH exert pro-cognitive, restorative, and protective properties in the brain. In in vitro studies, the detection of dendritic spines, small protrusions extending from axons, can act as a marker for cognition-related function as spine formation is considered to be associated with learning and memory. Here we show that an acute 24-hour treatment of GH can increase dendritic spine density in primary hippocampal cell cultures.

DESIGN

Primary hippocampal cells were harvested from embryonic Wistar rats and cultured for 14 days. Cells were treated with supra-physiological doses of GH (10-1000 nM) and subjected to a high-throughput screening protocol. Images were acquired and analyzed using automated image analysis and the number of spines, spines per neurite length, neurite length, and mean area of spines, was reported.

RESULTS

GH treatment (1000 nM) increased the number of dendritic spines by 83% and spines per neurite length by 82% when compared to control. For comparison BDNF, a known inducer of spine densities, produced statistically non-significant increase in this setting.

CONCLUSION

The results was found significant using the highest supra-physiological dose of GH, and the present study further confirms a potential role of the hormone in the treatment of cognitive dysfunction.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY GUIDELINES FOR MANAGEMENT OF GROWTH HORMONE DEFICIENCY IN ADULTS AND PATIENTS TRANSITIONING FROM PEDIATRIC TO ADULT CARE

Objective: The development of these guidelines is sponsored by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPG). Methods: Recommendations are based on diligent reviews of clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols. Results: The Executive Summary of this 2019 updated guideline contains 58 numbered recommendations: 12 are Grade A (21%), 19 are Grade B (33%), 21 are Grade C (36%), and 6 are Grade D (10%). These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world care of patients. The evidence base presented in the subsequent Appendix provides relevant supporting information for the Executive Summary recommendations. This update contains 357 citations of which 51 (14%) are evidence level (EL) 1 (strong), 168 (47%) are EL 2 (intermediate), 61 (17%) are EL 3 (weak), and 77 (22%) are EL 4 (no clinical evidence). Conclusion: This CPG is a practical tool that practicing endocrinologists and regulatory bodies can refer to regarding the identification, diagnosis, and treatment of adults and patients transitioning from pediatric to adult-care services with growth hormone deficiency (GHD). It provides guidelines on assessment, screening, diagnostic testing, and treatment recommendations for a range of individuals with various causes of adult GHD. The recommendations emphasize the importance of considering testing patients with a reasonable level of clinical suspicion of GHD using appropriate growth hormone (GH) cut-points for various GH-stimulation tests to accurately diagnose adult GHD, and to exercise caution interpreting serum GH and insulin-like growth factor-1 (IGF-1) levels, as various GH and IGF-1 assays are used to support treatment decisions. The intention to treat often requires sound clinical judgment and careful assessment of the benefits and risks specific to each individual patient. Unapproved uses of GH, long-term safety, and the current status of long-acting GH preparations are also discussed in this document. LAY ABSTRACT This updated guideline provides evidence-based recommendations regarding the identification, screening, assessment, diagnosis, and treatment for a range of individuals with various causes of adult growth-hormone deficiency (GHD) and patients with childhood-onset GHD transitioning to adult care. The update summarizes the most current knowledge about the accuracy of available GH-stimulation tests, safety of recombinant human GH (rhGH) replacement, unapproved uses of rhGH related to sports and aging, and new developments such as long-acting GH preparations that use a variety of technologies to prolong GH action. Recommendations offer a framework for physicians to manage patients with GHD effectively during transition to adult care and adulthood. Establishing a correct diagnosis is essential before consideration of replacement therapy with rhGH. Since the diagnosis of GHD in adults can be challenging, GH-stimulation tests are recommended based on individual patient circumstances and use of appropriate GH cut-points. Available GH-stimulation tests are discussed regarding variability, accuracy, reproducibility, safety, and contraindications, among other factors. The regimen for starting and maintaining rhGH treatment now uses individualized dose adjustments, which has improved effectiveness and reduced reported side effects, dependent on age, gender, body mass index, and various other individual characteristics. With careful dosing of rhGH replacement, many features of adult GHD are reversible and side effects of therapy can be minimized. Scientific studies have consistently shown rhGH therapy to be beneficial for adults with GHD, including improvements in body composition and quality of life, and have demonstrated the safety of short- and long-term rhGH replacement. Abbreviations: AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; AHSG = alpha-2-HS-glycoprotein; AO-GHD = adult-onset growth hormone deficiency; ARG = arginine; BEL = best evidence level; BMD = bone mineral density; BMI = body mass index; CI = confidence interval; CO-GHD = childhood-onset growth hormone deficiency; CPG = clinical practice guideline; CRP = C-reactive protein; DM = diabetes mellitus; DXA = dual-energy X-ray absorptiometry; EL = evidence level; FDA = Food and Drug Administration; FD-GST = fixed-dose glucagon stimulation test; GeNeSIS = Genetics and Neuroendocrinology of Short Stature International Study; GH = growth hormone; GHD = growth hormone deficiency; GHRH = growth hormone-releasing hormone; GST = glucagon stimulation test; HDL = high-density lipoprotein; HypoCCS = Hypopituitary Control and Complications Study; IGF-1 = insulin-like growth factor-1; IGFBP = insulin-like growth factor-binding protein; IGHD = isolated growth hormone deficiency; ITT = insulin tolerance test; KIMS = Kabi International Metabolic Surveillance; LAGH = long-acting growth hormone; LDL = low-density lipoprotein; LIF = leukemia inhibitory factor; MPHD = multiple pituitary hormone deficiencies; MRI = magnetic resonance imaging; P-III-NP = procollagen type-III amino-terminal pro-peptide; PHD = pituitary hormone deficiencies; QoL = quality of life; rhGH = recombinant human growth hormone; ROC = receiver operating characteristic; RR = relative risk; SAH = subarachnoid hemorrhage; SDS = standard deviation score; SIR = standardized incidence ratio; SN = secondary neoplasms; T3 = triiodothyronine; TBI = traumatic brain injury; VDBP = vitamin D-binding protein; WADA = World Anti-Doping Agency; WB-GST = weight-based glucagon stimulation test.

Adult growth hormone deficiency: clinical advances and approaches to improve adherence

Introduction: There have been significant clinical advances in the understanding of the diagnosis and benefits of long-term recombinant human growth hormone (rhGH) replacement in adults with GH deficiency (GHD) since its approval in 1996 by the United States Food and Drug Administration.Areas covered: We searched PubMed, Medline, CINAHL, EMBASE and PsychInfo databases between January 2000 and June 2019 for published studies evaluating adults with GHD. We reviewed the data of the oral macimorelin test compared to the GHRH plus arginine and the insulin tolerance tests that led to its approval by the United States FDA and European Medicines Agency for adult diagnostic testing. We summarize the clinical advances of long-term benefits of rhGH therapy and the potential effects of GH receptor polymorphisms on individual treatment responsiveness. We identify that non-adherence and discontinuation rates are high and recommend strategies to support patients to improve adherence. We also provide an overview of several long-acting GH (LAGH) preparations currently under development and their potential role in improving treatment adherence.Expert opinion: This article summarizes recent clinical advances in rhGH replacement therapy, the biological and molecular aspects that may influence rhGH action, and offers practical strategies to enhance adherence in adults with GHD.

Adherence, Attitudes and Beliefs of Growth Hormone Deficient Patients - A Questionnaire-based Cohort Study

INTRODUCTION

GHD is a chronic and systemic disease requiring daily replacement of growth hormone (GHRT). Adherence and attitudes of adult GHD patients are not well known. We sought to assess patients' knowledge of growth hormone deficiency (GHD) in association with treatment adherence and attitudes regarding available and upcoming treatment options.

METHODS

We performed a cross-sectional survey with a custom-made questionnaire at a single centre assessing data on demographics, knowledge of GHD, adherence and attitudes towards GHRT.

RESULTS

Of 106 eligible patients actively followed for GHD 70 returned the completed survey (return-rate 66%, 34 m/36 f; age 56±14 years). 46 patients were actively treated, but almost one third (n=24) refused GHRT. 12 patients had participated in clinical trials with LAGH (long-acting growth hormone). Overall, patients with GHRT showed good adherence. Patients refusing GHRT mostly feared side effects and/or had a lack of information/perceived effect. Disease knowledge and level of education were higher in treated than untreated patients (p=0.023/0.017). Only 36% of respondents would initiate treatment with LAGH. Patients with prior LAGH experience and patients with childhood-onset GHD were more likely to adopt LAGH (p=0.048/0.031).

DISCUSSION

Most often, misinformation causes patients to refuse GHRT. Possibly the understanding of their condition and consequences of non-treatment is limited. To improve adherence more focused educational and behavioural strategies may be needed. Willingness to begin a therapy with LAGH was lower than expected (36%). The reasons for reluctance against LAGH need to be elucidated.

Effects of somatotropic axis on cognitive dysfunction of obstructive sleep apnea

PURPOSE

Obstructive sleep apnea (OSA) is associated with a variety of neuroendocrine disorders and may lead to many complications, including cognitive dysfunction. The aim of this study was to assess the change of somatotropic axis and to detect the relation between somatotropic axis hormone and cognitive dysfunction.

METHODS

Sixty-six patients with OSA and 16 healthy controls were enrolled in this cross-sectional study. Cognitive function assessment using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) and polysomnography were performed on all individuals. Blood samples were taken the next morning following the polysomnography and the level of serum growth hormone-releasing hormone (GHRH) and growth hormone (GH) were analyzed by enzyme-linked immunosorbent assay.

RESULTS

Compared with the control group, OSA patients showed significantly lower serum GH level (p < 0.05), whereas no statistical significance of GHRH level was found. In addition, lower MMSE and MoCA scores were found only in the severe OSA patients when compared with the controls. Furthermore, in severe OSA patients with cognitive dysfunction (MMSE score < 27 and MoCA score < 26), serum GHRH and GH levels were significantly lower than those without cognitive dysfunction. Logistic analysis revealed that cognitive dysfunction in severe OSA patients was associated with micro-arousal index and the level of serum GHRH and GH.

CONCLUSION

Decreased serum GH and GHRH levels were found among severe OSA patients with cognitive dysfunction who were overweight, which might promote the occurrence of cognitive dysfunction.

The Protective and Restorative Effects of Growth Hormone and Insulin-Like Growth Factor-1 on Methadone-Induced Toxicity In Vitro

Evidence to date suggests that opioids such as methadone may be associated with cognitive impairment. Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) are suggested to be neuroprotective and procognitive in the brain and may therefore counteract these effects. This study aims to explore the protective and restorative effects of GH and IGF-1 in methadone-treated cell cultures. Primary cortical cell cultures were harvested from rat fetuses and grown for seven days in vitro. To examine the protective effects, methadone was co-treated with or without GH or IGF-1 for three consecutive days. To examine the restorative effects, methadone was added for the first 24 h, washed, and later treated with GH or IGF-1 for 48 h. At the end of each experiment, mitochondrial function and membrane integrity were evaluated. The results revealed that GH had protective effects in the membrane integrity assay and that both GH and IGF-1 effectively recovered mitochondrial function and membrane integrity in cells pretreated with methadone. The overall conclusion of the present study is that GH, but not IGF-1, protects primary cortical cells against methadone-induced toxicity, and that both GH and IGF-1 have a restorative effect on cells pretreated with methadone.

GH Therapy in Childhood Cancer Survivors: A Systematic Review and Meta-Analysis

BACKGROUND

GH deficiency (GHD) is common among childhood cancer survivors (CCSs) with history of tumors, surgery, and/or radiotherapy involving the hypothalamus-pituitary region. We aimed to evaluate the effects of GH therapy (GHT) in CCSs on adult height, risk of diabetes mellitus, abnormal lipids, metabolic syndrome, quality of life, secondary tumors, and disease recurrence.

METHODS

We searched multiple databases for randomized and observational studies. Pairs of reviewers independently selected studies and collected data. Random effects meta-analysis was used to pool outcomes across the studies.

RESULTS

We included 29 observational studies at moderate to high risk of bias. Sixteen studies compared CCSs on GHT with those not on GHT (512 patients, GH dose: 0.3 to 0.9 IU/kg/week). GHT was significantly associated with height gain [standard deviation score, 0.61; 95% CI, 0.08 to 1.13] and was not significantly associated with the occurrence of secondary tumors [odds ratio (OR), 1.10; 95% CI, 0.72 to 1.67] or tumor recurrence (OR, 0.57; 95% CI, 0.31 to 1.02). Thirteen studies compared CCSs on GHT with normal age- or sex-matched controls or controls with idiopathic GHD or short stature. GHT was associated with either improved or unchanged risk of diabetes, lipid profiles, and metabolic syndrome. GHT was associated with improvements in quality of life.

CONCLUSION

CCSs treated with GHT gain height compared with the untreated controls. GHT may improve lipid profiles and quality of life and does not appear to increase the risk of diabetes or the development of secondary tumors, although close monitoring for such complications remains warranted due to uncertainty in the current evidence.

Biomarkers of GH action in children and adults

Growth hormone (GH) and IGF-I levels in serum are used as biomarkers in the diagnosis and management of GH-related disorders but have not been subject to structured validation. Auxological parameters in children and changes in body composition in adults, as well as metabolic parameters and patient related outcomes are used as clinical and surrogate endpoints. New treatment options, such as long acting GH and GH antagonists, require reevaluation of the currently used biochemical biomarkers. This article will review biomarkers, surrogate endpoints and clinical endpoints related to GH treatment in children and adults as well as in acromegaly.

Treatment of adult growth hormone deficiency with human recombinant growth hormone: an update on current evidence and critical review of advantages and pitfalls

Adult-onset growth-hormone (GH) deficiency (GHD) is a rare disorder, which most commonly results from pituitary or peripituitary tumors and their treatment, and is characterized by alterations in body composition, carbohydrate and lipid metabolism, bone mineral density, cardiovascular risk profile and quality of life, all of which may contribute to an increased morbidity and mortality. Since recombinant human GH (rhGH) became available in 1985, several studies have provided evidence of its beneficial effects, despite the potential risk of developing adverse effects, and much clinical experience has been accumulated. However, in adults, the precise therapeutic role of GH replacement therapy and the individual response to it remains highly variable and is still a matter of debate. In this article, we present a critical review of the available evidence on rhGH replacement therapy in GHD adults, emphasizing the pitfalls clinicians encounter in the diagnosis of GHD and monitoring of rhGH replacement therapy. We will cover all the relevant aspects regarding the potential usefulness of GH treatment, including the hot topic of mortality.

Treatment with Growth Hormone for Adults with Growth Hormone Deficiency Syndrome: Benefits and Risks

Pharmacological treatment of growth hormone deficiency (GHD) in adults began in clinical practice more than 20 years ago. Since then, a great volume of experience has been accumulated on its effects on the symptoms and biochemical alterations that characterize this hormonal deficiency. The effects on body composition, muscle mass and strength, exercise capacity, glucose and lipid profile, bone metabolism, and quality of life have been fully demonstrated. The advance of knowledge has also taken place in the biological and molecular aspects of the action of this hormone in patients who have completed longitudinal growth. In recent years, several epidemiological studies have reported interesting information about the long-term effects of GH replacement therapy in regard to the possible induction of neoplasms and the potential development of diabetes. In addition, GH hormone receptor polymorphism could potentially influence GH therapy. Long-acting GH are under development to create a more convenient GH dosing profile, while retaining the excellent safety, efficacy, and tolerability of daily GH. In this article we compile the most recent data of GH replacement therapy in adults, as well as the molecular aspects that may condition a different sensitivity to this treatment.

Growth Hormone (GH) and Gonadotropin-Releasing Hormone (GnRH) in the Central Nervous System: A Potential Neurological Combinatory Therapy?

This brief review of the neurological effects of growth hormone (GH) and gonadotropin-releasing hormone (GnRH) in the brain, particularly in the cerebral cortex, hypothalamus, hippocampus, cerebellum, spinal cord, neural retina, and brain tumors, summarizes recent information about their therapeutic potential as treatments for different neuropathologies and neurodegenerative processes. The effect of GH and GnRH (by independent administration) has been associated with beneficial impacts in patients with brain trauma and spinal cord injuries. Both GH and GnRH have demonstrated potent neurotrophic, neuroprotective, and neuroregenerative action. Positive behavioral and cognitive effects are also associated with GH and GnRH administration. Increasing evidence suggests the possibility of a multifactorial therapy that includes both GH and GnRH.

Update on GH therapy in adults

Over the last three decades, short- and long-term observational studies, clinical trials, systematic reviews, and meta-analyses have provided relevant information on the efficacy and safety of growth hormone (GH) replacement therapy in adults with GH deficiency (AGHD). The knowledge acquired during this time has been compiled into different guidelines that offer clinicians an evidence-based, practical approach for the management of AGHD. There are, however, still open questions in some key areas in which recommendations are supported by only moderate or weak evidence. In the last recent years, the development of long-acting GH preparations has created new therapeutic possibilities by decreasing injection frequency, improving adherence and thereby potentially maximizing clinical outcomes. The aims of this review are to advance our understanding on the diagnosis and treatment of AGHD and to present an update and future perspectives on the use of long-acting GH preparations.

Oral glucose-stimulated growth hormone (GH) test in adult GH deficiency patients and controls: Potential utility of a novel test

CONTEXT

The diagnosis of adult GH deficiency requires confirmation with a GH stimulation test. Oral glucose (OG) administration affects GH secretion, initially decreasing and subsequently stimulating GH secretion.

OBJECTIVE

The aim of this study was to investigate the diagnostic efficacy and safety of a long OG test (LOGT) as a stimulus of GH secretion for the diagnosis of adult GH deficiency (AGHD).

DESIGN

Prospective experimental cross-sectional study.

SETTINGS

The study was conducted at the Endocrinology department of the University Hospital of a Coruña, Spain.

PARTICIPANTS AND METHODS

We included 60 (40 women) AGHD patients (15) and controls (45) paired 1:3, of similar age, sex and BMI. The area under the curve (AUC) and peak were calculated for GH. The Mann-Whitney test was used to compare the different groups. ROC curve analyses were used. p-Values<0.05 were considered as statistically significant.

INTERVENTIONS

The intervention consisted of orally administering 75g oral glucose administration; GH was obtained every 30min for a total of 300min.

MAIN OUTCOME MEASUREMENT

Peak GH area under receiver operating characteristic curve (ROC-AUC) following LOGT.

RESULTS

Peak GH (μg/L) levels were lower in the AGHD patients (0.26±0.09) than in the controls (4.00±0.45), p<0.001. After LOGT, with the ROC plot analysis the best peak GH cut-point was 1.0μg/L, with 100% sensitivity, 78% specificity, ROC-AUC of 0.9089 and 81.82% accuracy. There were no relevant adverse events during any of the LOGT.

CONCLUSIONS

The LOGT could be a cheap, safe, convenient and effective test for the diagnosis of AGHD.