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

Causal relationship between sleep characteristics and thyroid function: A bidirectional Mendelian randomization study

BACKGROUND

Previous researches have revealed some links between thyroid function and sleep characteristics, however it remains unclear which one causes the other. The purpose of this study was to investigate the potential causal relationship between hyperthyroidism, hypothyroidism, and sleep characteristics.

METHODS

We utilized aggregated data from published genome-wide association studies (GWAS) to select genetic instruments for sleep variables. The 5 sleep-related traits (chronotype, short sleep duration, long sleep duration, daytime sleepiness, and insomnia) were associated with distinct genetic variants chosen as instrumental factors. Employing MR Egger's analysis of Mendelian randomization (MR), weighted median, weighted mode, and inverse variance weighted (IVW) methods to assess the 5 sleep traits in relation to hyperthyroidism and hypothyroidism, we subsequently conducted inverse MR analysis to examine the causal relationship between thyroid function and the 5 sleep characteristics.

RESULTS

The IVW technique did not reveal a causal association between chronotype, short sleep duration, long sleep duration, daytime sleepiness, or insomnia and the risk of abnormal thyroid function in the study investigating the influence of sleep characteristics on this risk. The outcomes of the IVW approach were consistent with the remaining 3 methods. The IVW, weighted median, MR Egger, and weighted mode methods in the reverse magnetic resonance imaging investigation did not yield evidence of a causative association between the risk of time type, long sleep duration, and insomnia and abnormal thyroid function. In contrast, the weighted median and weighted mode methods showed a possible causal relationship between hypothyroidism and short sleep duration and daytime sleepiness. Sensitivity analyses showed that the results were robust and no pleiotropy or heterogeneity was detected.

CONCLUSION

More precisely, our analysis did not uncover any indication of a reciprocal causal link between thyroid function and genetically predicted sleep characteristics.

A 2024 Update on Growth Hormone Deficiency Syndrome in Adults: From Guidelines to Real Life

Background: Adult growth hormone deficiency (GHD) has been recognized since the late 1980s. The clinical manifestations of adult GHD are often nonspecific, and diagnosis relies on GH stimulation tests, which are intricate, costly, time-consuming, and may carry the risk of adverse effects. Diagnosis is further complicated by factors like age, sex, and BMI, which affect GH response during testing. Therefore, GH replacement therapy remains challenging, requiring careful individualized evaluation of risks and benefits. The aim of this review is to provide an update on diagnosing and treating adult GHD, addressing current limitations and challenges based on recent studies. Methods: We conducted a comprehensive review of the literature regarding the diagnosis and management of adult GHD by searching PubMed and EMBASE. Only articles in English were included, and searches were conducted up to August 2024. Results: A review of guidelines and literature up to 2024 highlights the significant heterogeneity in the data and reveals various protocols for managing GHD, covering both diagnostic and therapeutic approaches. Conclusions: Despite diagnostic and treatment advances, managing adult GHD remains challenging due to variable presentation and the need for personalized GH therapy. Future efforts should aim to improve and standardize diagnostic and treatment protocols.

Development and validation of a novel treatment adherence, satisfaction and knowledge questionnaire (TASK-Q) for adult patients with hypothalamic-pituitary disorders

PURPOSE

Successful treatment outcomes of adults with hypothalamic-pituitary disorders necessitate the adoption of intricate self-management behaviors, yet current scales for evaluating treatment adherence and satisfaction are inadequate for this patient group. This research introduces a novel treatment adherence, satisfaction and knowledge questionnaire (TASK-Q) developed specifically to identify patients' unmet needs in better assessing and managing these disorders.

METHODS

The study was conducted in three phases: (1) generating items and testing content validity, (2) refining these items through a pilot study, and (3) a main study evaluating the psychometric properties of the TASK-Q scale among 262 adults in a Pituitary Nurse-led Clinic, with 152 (58%) patients completing the questionnaire.

RESULTS

Exploratory factor analysis was used to test the factor structure and construct validity of the TASK-Q, revealing a 22-item scale divided into Satisfaction and Knowledge (17 items) and Adherence (5 items) subscales, and exhibiting high internal consistency (Cronbach's α = 0.90). Significant correlations were identified between satisfaction and knowledge (r = 0.67, p < 0.001), satisfaction and adherence (r = 0.23, p = 0.005), and knowledge and adherence (r = 0.43, p < 0.001). Complex treatment regimens, like daily growth hormone injections and adjusting glucocorticoids during illness, negatively affected adherence (p < 0.001).

CONCLUSION

The TASK-Q is a novel validated scale that can effectively evaluate patients' perspectives on adherence, knowledge and satisfaction. Our findings highlight the significant impact of Advanced Nurse Practitioners in improving patient self-management behaviors, which likely leads to better treatment outcomes for people with hypothalamic-pituitary disorders.

Utilizing Somapacitan, a Long-acting Growth Hormone Formulation, for the Treatment of Adult Growth Hormone Deficiency: A Guide for Clinicians

OBJECTIVE

Somapacitan is the first approved and currently the only long-acting growth hormone (GH) formulation in the United States for treatment of adults with growth hormone deficiency (GHD). The aim of this review was to provide a practical approach for clinicians on how to utilize somapacitan in the treatment of adults with GHD.

METHODS

Literature search was performed on PubMed using key words, including adult GHD, long-acting growth hormone, somapacitan, treatment, and management. The discussion of treatment aspects utilizing somapacitan was based on evidence from previous clinical studies and personal experience.

RESULTS

Clinical trial data demonstrated that somapacitan, a once-weekly reversible albumin-binding GH derivative, decreased truncal fat, improved visceral fat and lean body mass, increased insulin-like growth factor-I standard deviation score and exerted neutral effects on glucose metabolism. Overall, somapacitan was well-tolerated, adverse event rates were comparable with daily GH, antisomapacitan or anti-GH antibodies were not detected, and treatment satisfaction was in favor of somapacitan vs daily GH.

CONCLUSION

Somapacitan is an efficacious, safe, convenient and well-tolerated once-weekly long-acting GH formulation that reduces the treatment burden of once-daily GH injections for adults with GHD. This article provides a review of the pharmacology of somapacitan and offers practical recommendations based on previous clinical trial data on how to initiate, dose titration, monitoring and dose adjustments whilst on therapy in adults with GHD. Timing of measurement of serum insulin-like growth factor-I levels, information on administration, recommendations on missed doses, and clinical recommendations on dosing in certain sub-population of patients are also discussed.

Causal relationship between insomnia and thyroid disease: A bidirectional Mendelian randomization study

OBJECTIVE

Some correlations between thyroid disorders and insomnia have been found in previous studies; however, the causal relationship between them is unclear. The aim of this study was to investigate the causal relationship between insomnia and five thyroid disorders (hyperthyroidism, hypothyroidism, thyroiditis, thyroid nodules, and thyroid cancer).

METHODS

We assessed the causal relationship between insomnia and thyroid disorders using inverse variance weighted, weighted median, and Mendelian randomization (MR)-Egger analyses in MR analyses and then used inverse MR analyses to assess the causal relationship between thyroid disorders and insomnia.

RESULTS

MR analysis showed that insomnia did not increase the risk of hyperthyroidism, hypothyroidism, thyroiditis, thyroid nodules, and thyroid cancer. However, reverse MR analysis showed that thyroid cancer increased the risk of insomnia (OR = 1.01, 95%CI: 1.00-1.02, p = .01), and the other four thyroid disorders had no direct causal relationship with insomnia. Sensitivity analyses indicated that the results were robust and no pleiotropy or heterogeneity was detected.

CONCLUSION

This study did not find evidence of a bidirectional causal relationship between genetically predicted insomnia and hyperthyroidism, hypothyroidism, thyroiditis, and thyroid nodules. However, we found that although insomnia does not increase the risk of thyroid cancer, thyroid cancer does increase the risk of insomnia.

Investigating the Bioavailability and Insulin-like Growth Factor-I Release of Two Different Strengths of Somapacitan: A Randomised, Double-Blind Crossover Trial

STUDY DESIGN AND OBJECTIVE

Randomised, double-blind, crossover trial to confirm bioequivalence of somapacitan, a long-acting growth hormone (GH), in 5 mg/1.5 mL and 10 mg/1.5 mL strengths in equimolar doses.

METHODS

Healthy participants were randomised (1:1:1) to subcutaneous somapacitan treatment in one dosing period with 5 mg/1.5 mL and two periods with 10 mg/1.5 mL. Eligibility criteria included age 18-45 years and body mass index 18.5-24.9 kg/m2. Exclusion criteria included history of GH deficiency, previous GH treatment, weight > 100.0 kg and participation in any clinical trial of an investigational medicinal product within 45 days or five times the half-life of the previous investigational product before screening. Area under the curve from time 0 until last quantifiable observation (AUC0-t), maximum serum concentration (Cmax), time to Cmax and terminal half-life of somapacitan and safety were assessed.

RESULTS

In total, 33 participants were randomised. For AUC0-t, estimated treatment ratio (ETR) (5 mg/1.5 mL versus 10 mg/1.5 mL) was 0.95 (90% confidence interval [CI] 0.89-1.01). Point estimate and 90% CIs were within the acceptance range (0.80-1.25). For Cmax, ETR was 0.77 (90% CI 0.68-0.89). Point estimate and 90% CIs were outside the acceptance range (0.80-1.25). Mean insulin-like growth factor-I (IGF-I) and IGF-I standard deviation score concentration-time curves for each strength were almost identical. No new safety issues were identified.

CONCLUSIONS

Bioequivalence criterion for somapacitan 5 mg/1.5 mL and 10 mg/1.5 mL was met for AUC0-t but not for Cmax. The two strengths had equivalent IGF-I responses.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03905850 (3 April 2019).

Safety of long-term use of daily and long-acting growth hormone in growth hormone-deficient adults on cancer risk

Daily injections of recombinant human growth hormone (rhGH) have been used in clinical practice for almost four decades as a replacement therapy in adult patients with GH deficiency (GHD). Long-term adherence to daily injections of rhGH is a clinical concern that may result in reduced therapeutic efficacy, and long-acting GH (LAGH) formulations have been developed in an attempt of overcoming this problem. Long-term safety issues of rhGH are the other side of the coin that has been carefully monitored over the years, particularly related to the proliferative actions of GH that could increase the risk of tumor recurrence or induce the development of new benign and malignant tumors. In this review, we present what is currently known about the cancer risk in GHD adults treated with daily rhGH injections and we discuss the major concerns and responses needed from future surveillance studies regarding the safety of LAGH preparations.

The relationship between sleep duration and thyroid function in the adult US population: NHANES 2007-2012

OBJECTIVE

Sleep disturbance is a common problem in the general population. Sleep deprivation or dysfunction can have profound health consequences. However, how sleep duration is associated with thyroid function remains unclear. This study was thus developed to examine the association between sleep duration and thyroid function in the US adult population.

METHODS

A total of 8102 participants from the NHANES 2007-2012 dataset were included in this study. Weighted data analyses were conducted, and the link between sleep duration and thyroid function was probed using linear regression models with smoothed curve fitting. Stratified analyses were also performed.

RESULTS

Weighted mean (standard deviation) values for study variables were as follows: sleep duration 6.85 (0.02) hours, thyroid-stimulating hormone (TSH) 1.86 (0.03) mIU/ml, serum free T3 3.20 (0. 01) pg/mL, serum free T4 0.80 (0.01) ng/dL, serum total T3 115.12 (0.64) ng/dL, serum total T4 7.81 (0.04) ug/dL, TPOAb 16.20 (1.53) IU/mL, TgAb 5.75 (0.73) IU/mL, and Tg 15.11 (0.46) ng/mL. In unadjusted analyses, increased sleep duration was associated with higher serum TSH levels and decreased FT3 levels. After adjustment for potential confounders, a significant negative relationship was detected between sleep duration and FT3 levels in participants with ≤7 hours of sleep. When sleep duration exceeded 7 hours, no significant changes in FT3 levels were observed after further increases in sleep duration.

CONCLUSION

Increased sleep duration was related to decreased FT3 levels, primarily at short sleep durations, and this correlation was no longer evident when participants reached the recommended healthy sleep duration.

Contribution of Dynamic and Genetic Tests for Short Stature Diagnosing: A Case Report

Genetic tests have led to the discovery of many novel genetic variants related to growth failure, but the clinical significance of some results is not always easy to establish. The aim of this report is to describe both clinical phenotype and genetic characteristics in an adult patient with short stature associated with a homozygous variant in disintegrin and metalloproteinase with thrombospondin motifs type 17 gene (ADAMTS17) combined with a homozygous variant in the GH secretagogue receptor (GHS-R). The index case had severe short stature (SS) (-3.0 SD), small hands and feet, associated with eye disturbances. Genetic tests revealed homozygous compounds for ADAMTS17 responsible for Weill-Marchesani-like syndrome but a homozygous variant in GHS-R was also detected. Dynamic stimulation with an insulin tolerance test showed a normal elevation of GH, while the GH response to macimorelin stimulus was totally flattened. We show the implication of the GHS-R variant and review the molecular mechanisms of both entities. These results allowed us to better interpret the phenotypic spectrum, associated co-morbidities, its implications in dynamic tests, genetic counselling and treatment options not only to the index case but also for her relatives.

Dose-exposure-IGF-I response of once-weekly somapacitan in adults with GH deficiency

OBJECTIVE

Growth hormone (GH) replacement therapy in patients with adult growth hormone deficiency (AGHD) is individually titrated due to variable dose-responses among patients. The aim of this study was to provide clinical guidance on dosing and titration of the novel long-acting GH derivative somapacitan based on analyses of somapacitan dose-insulin-like growth factor I (IGF-I) responses in AGHD patients.

DESIGN

Analyses of dosing information, 4364 somapacitan concentration samples and 4880 IGF-I samples from 330 AGHD patients treated with somapacitan in three phase 3 trials.

METHODS

Pharmacokinetic/pharmacodynamic modelling was used to evaluate starting dose groups by age and oral oestrogen therapy, characterise the dose-IGF-I response in the overall AGHD population and patient subgroups, predict the IGF-I response to dose changes and simulate missed dosing.

RESULTS

The analyses supported the clinical recommendations of higher starting doses for younger patients and women on oral oestrogen replacement therapy. For patients switching from daily GH treatment, the mean maintenance dose ratio between somapacitan (mg/week) and somatropin (mg/day) was predicted to be 8.2 (observed interquartile range of 6.7-9.1). Simulations of IGF-I SDS profiles confirmed the appropriate time for IGF-I sampling to be 3-4 days after somapacitan dosing and supported somapacitan administration with up to 3 days delay in case of missed dosing. Subgroup analyses characterised the dose-exposure-IGF-I response in patient subgroups and indicated that dose requirements are mainly influenced by sex and oral oestrogen treatment.

CONCLUSIONS

This study extends the knowledge of the somapacitan dose-IGF-I response and provides information on clinical dosing of once-weekly somapacitan in patients with AGHD.

Effects of adult growth hormone deficiency and replacement therapy on the cardiometabolic risk profile

Adult growth hormone deficiency (AGHD) is considered a rare endocrine disorder involving patients with childhood-onset and adult-onset growth hormone deficiency (AoGHD) and characterized by adverse cardiometabolic risk profile. Besides traditional cardiovascular risk factors, endothelial dysfunction, low-grade inflammation, impaired adipokine profile, oxidative stress and hypovitaminosis D may also contribute to the development of premature atherosclerosis and higher cardiovascular risk in patients with AGHD. Growth hormone replacement has been proved to exert beneficial effects on several cardiovascular risk factors, but it is also apparent that hormone substitution in itself does not eliminate all cardiometabolic abnormalities associated with the disease. Novel biomarkers and diagnostic techniques discussed in this review may help to evaluate individual cardiovascular risk and identify patients with adverse cardiometabolic risk profile. In the absence of disease-specific guidelines detailing how to assess the cardiovascular status of these patients, we generally recommend close follow-up of the cardiovascular status as well as low threshold for a more detailed evaluation.

A meta-analysis of combination therapy with gonadotrophin-releasing hormone agonist and growth hormone for children with idiopathic short stature and normal timed puberty

PURPOSE

The aim of this meta-analysis is to evaluate whether the combination therapy with gonadotrophin-releasing hormone agonist (GnRHa) and recombinant human growth hormone (rhGH) are effective in the treatment of children with idiopathic short stature (ISS) and normal timed puberty by interrogating data from clinical controlled trials.

METHODS

Literature retrieval, trail selection, data abstraction and quality assessment were completed independently by two authors. STATA software (version 14.1) was used for data analyses.

RESULTS

This meta-analysis was conducted based on 8 (4 randomized and 4 non-randomized) controlled trials. A total of 245 ISS children with normal timed puberty were financially analyzed. Overall, combination therapy with GnRHa and rhGH can slightly increase final height by 3.70 and 3.43 cm compared with GH treatment alone and no treatment, final height standard deviation score (FHSDS) by 0.10 and 0.22, final height minus predicted adult height (FH-PAH) by 1.5 and 5.32 cm, final height minus predicted adult height (FH-TH) by 7.70 and 4.32 cm, respectively. Subgroup and meta-regression analyses revealed that study type, sample size, GnRHa duration, and percentage of boys were potential sources of between-trial heterogeneity. There was a low probability of publication bias for above comparisons, as indicated by Egger's tests.

CONCLUSIONS

Our meta-analytical findings indicate that the combination therapy with GnRHa and rhGH can slightly increase the final height of ISS children with normal timed puberty, and the effect was not more obvious than GH alone. We do not recommend the combination therapy as a routine treatment for ISS.

TRIAL REGISTRATION NUMBER

CRD42019133438.

Guidance for the treatment of adult growth hormone deficiency with somapacitan, a long-acting growth hormone preparation

Adult growth hormone deficiency (AGHD) is a rare endocrine disorder characterized by an abnormal body composition, metabolic abnormalities associated with increased cardiovascular diseases, bone loss, and impaired quality of life. Daily subcutaneous injections with recombinant growth hormone (GH) can alleviate the abnormalities associated with AGHD. Several long-acting GH (LAGH) preparations are currently in development that aim to reduce treatment burden for patients receiving daily GH injections. Somapacitan (Sogroya^®; Novo Nordisk, Denmark) is the first LAGH preparation that has been approved for treatment of AGHD in the United States, Europe, and Japan. The recent approval of somapacitan and anticipated approval of other LAGH molecules presents new questions for physicians planning to treat AGHD with LAGH in the future. Differences in the technologies used to prolong the half-life of recombinant GH are expected to result in variations in pharmacokinetic and pharmacodynamic profiles between preparations. Therefore, it is essential that physicians understand and consider such variations when treating patients with these novel GH replacement therapies. Here, we present a set of treatment recommendations that have been created to guide physicians initiating therapy with somapacitan in patients with AGHD who are eligible for GH replacement. Furthermore, we will review the published data that underlie these recommendations to explain the rationale for the treatment and monitoring advice provided.

The Hypothalamic Pituitary Thyroid Axis and Sleep

Sleep has a bidirectional relationship with the hypothalamic-pituitary-thyroid (HPT) axis, and both these homeostatic processes are inter-dependent for robust physiological functioning. The quality and quantity of sleep influence the circadian pattern of TSH and thyroid hormone secretion. Short term sleep restriction significantly reduces the amplitude of nocturnal TSH secretion and may modulate active thyroid hormone secretion, likely through an increased sympathetic tone. Conversely, TSH and active thyroid hormone affect the quantity and architecture of sleep. For instance, low TSH values are permissive for slow wave sleep and maintenance of normal sleep architecture, while the hypo- or hyper-secretion of active thyroid hormones adversely affects the quality and quantity of sleep. Structural thyroid disorders may also be associated with an altered circadian clock - a phenomenon warranting further investigation. In this review, we aim to provide readers a comprehensive review on the associations between the HPT axis and sleep patterns.

Vasculometabolic effects in patients with congenital growth hormone deficiency with and without GH replacement therapy during adulthood

PURPOSE

To evaluated the metabolic profiles and vascular properties in congenital growth hormone (GH) deficiency (GHD) and its replacement in adults.

PATIENTS AND METHODS

Cross-sectional study conducted in a single tertiary center for pituitary diseases. Eighty-one adult subjects were divided into three groups: (1) 29 GHD patients with daily subcutaneous GH replacement therapy (GHRT) during adulthood; (2) 20 GHD patients without GHRT during adulthood and (3) 32 controls. Only patients with adequate adherence to others pituitary hormone deficiencies were included. Anthropometric parameters, body composition by dual-energy X-ray absorptiometry, metabolic profiles and vascular properties (carotid intima media thickness, pulse wave velocity and flow-mediated dilation) were compared among the groups.

RESULTS

Waist-to-height ratio (WHR), body fat percentages and fat mass index (FMI) were lower in patients with GHRT than patients without GHRT during adulthood (0.49 ± 0.06 vs. 0.53 ± 0.06 p = 0.026, 30 ± 10 vs. 40 ± 11 p = 0.003 and 7.3 ± 4 vs. 10 ± 3.5 p = 0.041, respectively). In addition, association between longer GHRT and lower body fat percentage was observed (r =  - 0.326, p = 0.04). We found higher triglyceride (113.5 ± 62 vs. 78 ± 36, p = 0.025) and lower HDL cholesterol (51 ± 17 vs. 66 ± 23, p = 0.029) levels in patients without GHRT during adulthood in comparison to controls. No statistical differences were observed for vascular properties among the groups.

CONCLUSIONS

No differences in vascular properties were observed in congenital GHD adult patients with or without GHRT despite patients without GHRT had an unfavorable body composition. GHRT currently remains an individualized decision in adults with GHD and these findings bring new insight into the treatment and follow-up of these patients.

Growth hormone deficiency and replacement in children

Growth hormone deficiency (GHD) is a rare but treatable cause of short stature. The diagnosis requires a careful evaluation of clinical history, physical examination and appropriate interpretation of longitudinal growth, with specific features for each period of life. Other clinical findings, in addition to growth failure, may be present and can be related to the etiology and to associated hormone deficiencies. Despite more than 50 years since the first reports of provocative tests of growth hormone (GH) secretion for the diagnosis of GHD, the interpretation of the results remains a matter of debate. When GHD is confirmed, GH treatment is recommended. Treatment is effective and safe, but requires daily injections during many years, which can affect adherence. At the end of longitudinal growth, during the transition phase, it might be necessary to re-evaluate GH secretion. This review summarizes and updates the recent information related to GHD in children, as well the recommendations for treatment.

Adult growth hormone deficiency: Optimizing transition of care from pediatric to adult services

OBJECTIVE

Most patients with childhood-onset growth hormone deficiency (CO-GHD) receive treatment with exogenous growth hormone (GH) to facilitate the attainment of their full potential adult height. Recent evidence suggests that continuing GH administration during the transition period between the end of linear growth and full adult maturity is necessary for proper body composition and bone and muscle health, and may also have beneficial effects on metabolic parameters, bone mineral density, and quality of life. The timing of this transition period coincides with the transfer of care from a pediatric to an adult endocrinologist, creating the potential for a care gap as a consequence of losing the patient to follow-up.

DESIGN

An advisory board comprising both pediatric and adult endocrinologists was assembled to address current clinical unmet needs and to collaborate on a structured transitional plan for optimal management of patients with CO-GHD.

INSIGHTS/CONCLUSION

The advisors suggest collaborative, multidisciplinary approaches to ensure continuity of care; ongoing testing and monitoring of GHD status into adulthood; and a clearly structured protocol that includes practical guidance for clinicians to establish best practices for transitioning older adolescents with persistent CO-GHD to adult care.

Sensitivity and specificity of the macimorelin test for diagnosis of AGHD

OBJECTIVE

The macimorelin test is approved for the diagnosis of adult growth hormone deficiency (AGHD) based on its efficacy vs the insulin tolerance test (ITT). Macimorelin has a significant advantage over ITT in avoiding hypoglycemia. Analyses were conducted to determine whether macimorelin performance is affected by age, BMI, or sex, and evaluate its performance vs ITT over a range of GH cutpoints.

DESIGN

Post hoc analyses of data from a previous randomized phase 3 study included participants aged 18-66 years with BMI <37 kg/m2 and high (Group A), intermediate (Group B), or low (Group C) likelihood for AGHD based on pituitary history, and matched controls (Group D).

METHODS

Probability of AGHD was estimated using unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted logistic models. Area under the curve (AUC) of the estimated receiver operating characteristic (ROC) curve (range, 0-1; 1 = perfect) was compared for adjusted vs unadjusted models. Separate analyses evaluated agreement, sensitivity, and specificity for macimorelin and ITT using cutpoints of 2.8, 4.0, 5.1, and 6.5 ng/mL.

RESULTS

For participants in Group A (n = 41) and Group D (n = 29), unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted models had ROC AUCs (95% CIs) of 0.9924 (0.9807-1), 0.9924 (0.9807-1), 0.9916 (0.9786-1), and 0.9950 (0.9861-1), respectively.

CONCLUSIONS

Macimorelin performance was not meaningfully affected by age, BMI, or sex, indicating robustness for AGHD diagnosis. Of the 4 GH cutpoints evaluated, the cutpoint of 5.1 ng/mL provided maximal specificity (96%) and high sensitivity (92%) and was in good overall agreement with the ITT at the same cutpoint (87%).

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.

Similar safety and efficacy in previously treated adults with growth hormone deficiency randomized to once-weekly somapacitan or daily growth hormone

OBJECTIVE

Somapacitan is a long-acting, reversible albumin-binding growth hormone (GH) derivative in development. This study aimed to evaluate the safety and efficacy of once-weekly somapacitan versus daily GH over 52 weeks in Japanese patients with adult growth hormone deficiency (AGHD).

DESIGN

Phase 3, multicentre, randomized, parallel-group, open-label, active-controlled trial (NCT03075644).

PATIENTS

Previously GH-treated Japanese patients with AGHD were randomized 3:1 to somapacitan (n = 46) or daily GH (n = 16) for 20 weeks' dose titration and 32 weeks' fixed-dose treatment.

MEASUREMENTS

Primary endpoint was the incidence of adverse events (AEs). Secondary endpoints included change from baseline to week 52 in visceral, subcutaneous and total adipose tissue (VAT, SAT and TAT).

RESULTS

Mean (SD) prescribed doses after titration were 1.780 (1.058) mg/week for somapacitan and 0.197 (0.083) mg/day for daily GH. Rate of AEs per 100 patient-years was similar between arms (somapacitan, 312.7; daily GH, 309.8). Four AEs in the somapacitan arm were serious; none were considered treatment-related. Mean insulin-like growth factor-I standard deviation score (IGF-I SDS) was maintained from baseline in both arms. No significant differences were observed between arms for change from baseline to week 52 in VAT, SAT or TAT (estimated difference, somapacitan - daily GH [95% CI]: -1.74 [-18.13; 14.66], -11.53 [-35.54; 12.48] and - 12.85 [-47.31; 21.62] cm² , respectively).

CONCLUSIONS

Treatment in both groups was well tolerated, with no unexpected safety findings. Impact on adipose tissue was similar to somapacitan and daily GH in patients with AGHD. A short visual summary of our work is available at https://bit.ly/3946YNF.

Combined therapy with GnRH analogue and growth hormone increases adult height in children with short stature and normal pubertal onset

OBJECTIVE

To investigate whether gonadotropin releasing hormone analogue (GnRHa) combined with recombinant human growth hormone (rhGH) can improve the adult height (AHt) of children with short stature and normal pubertal onset.

METHODS

In this retrospective study, GnRHa/rhGH treatment was given to children with normal pubertal onset and short stature. Patients were followed up to measure their AHt. The primary outcomes were the disparity between AHt standard deviation score (AHt SDS) and pre-treatment height standard deviation score (Ht SDS) and the disparity between AHt and target height (THt).

RESULTS

A total of 94 patients were included. Forty-nine boys were treated with GnRHa/rhGH for 24.84 ± 13.01 months, and 45 girls were treated for 23.89 ± 10.43 months. (2) Before treatment, the Ht SDS of boys and girls was -1.82 ± 1.30 and -1.10 ± 1.61, respectively, and the target height was 168.98 ± 3.51 cm and 157.90 ± 3.25 cm, respectively. (3) After treatment, for boys, the AHt SDS increased by 1.37 ± 1.28 (p = 0.000) and the disparity between AHt and THt was 0.98 ± 6.18 cm (p = 0.273); for girls, the AHtSDS increased by 1.28 ± 1.48 (p = 0.000), and the disparity between AHt and THt was 3.64 ± 4.86 cm (n = 45, p = 0.000). (4) Subgroup analysis showed that, for boys with idiopathic short stature (ISS) and non-ISS, AHt SDS increased by 2.00 ± 1.16 (p = 0.000) and 0.71 ± 1.06 (p = 0.003) respectively, compared with the pre-treatment HtSDS; The disparities between AHt and THt were -0.70 ± 6.54 cm and 2.73 ± 5.37 cm respectively. For girls with ISS and non-ISS, AHtSDS increased by 2.73 ± 1.21 (p = 0.000) and 0.748 ± 1.19 (p = 0.001), respectively; AHt increased by 2.63 ± 6.12 cm (p = 0.165) and 4.02 ± 4.37 cm (p = 0.000) compared with THt, respectively. (5) Multiple linear regression analysis showed that the baseline bone age (BA) (β = -0.200, p = 0.003), basal IGF-1(β = -0.002, p = 0.008) and HtSDS (β = -0.679, p = 0.000) had negative effects on increment of AHtSDS.

CONCLUSION

For adolescents with normal pubertal onset and short stature, with or without ISS, GnRHa/rhGH therapy can effectively improve AHtSDS. After treatment, ISS adolescents can reach the THts, and Non-ISS adolescents can exceed their THts.

Comparison of nocturnal and morning ghrelin concentration in children with growth hormone deficiency and with idiopathic short stature

Ghrelin - a growth hormone (GH) secretagogue - presents a circadian rhythm with higher nocturnal than diurnal concentration (similar to GH). However, daily ghrelin production depends on food intake and nutritional state; it is increased in the fasting state and decreased after a meal. Since most past research concerning short stature children has relied on the morning ghrelin concentration for analyses, we decided to assess ghrelin concentration at the 60^th and 90^th minute after falling asleep and in the morning at 06:00 h, shortly after waking up from nighttime sleep (after 12 h of fasting). We compared these ghrelin concentrations to determine differences between nocturnal and morning ghrelin release in short children, both with idiopathic short stature (ISS) and growth hormone deficiency (GHD). We also analyzed the correlation between the nocturnal and morning ghrelin concentrations with nocturnal GH concentrations, measured at the same time points, as well as with maximal GH concentration, achieved by stimulation tests, and with the insulin-like growth factor I (IGF-I). The ghrelin and GH concentration 60^th and 90^th minute after falling asleep, as well as fasting morning ghrelin and IGF-I concentrations, were measured in 19 (n = 10 ISS and n = 9 GHD) prepubertal short children (7 girls and 12 boys), aged 10.36 ± 3.06 y. Differences between the nocturnal and morning ghrelin concentrations were analyzed by the Wilcoxon matched-pairs signed-rank test. Typical regression and correlation analyses were used to assess relationships among parametric data for other analyses. The Wilcoxon test showed ghrelin concentration is significantly higher in the morning than both at the 60^th and 90^th minute after falling asleep time points (in ISS and GHD). A significant correlation was observed: a) positive - between nocturnal ghrelin (both at the 60^th and 90^th minute) and morning ghrelin concentrations; b) positive - between ghrelin at the 60^th minute and nocturnal GH concentrations (both at the 60^th and 90^th minute); c) negative - between ghrelin at the 60^th minute and IGF-I concentrations; and d) negative - between body mass index and ghrelin concentrations at the 60^th and 90^th minute. We conclude: 1) in short children, both with GHD and with ISS, morning ghrelin level reflects its nocturnal concentration; however, it is significantly higher than the nocturnal ones. There is no significant difference between the measurement of ghrelin concentration at night at the 60^th or 90^th minute after falling asleep; 2) morning ghrelin concentration is affected by the hunger and satiety; therefore, it appears that nocturnal measurements better reflect the pool of hormone responsible for stimulation of GH and IGF-I secretion, especially since positive correlation between nocturnal ghrelin and nocturnal GH secretion was noted; 3) it seems that a higher body mass index is an additional independent factor, associated mainly with lower nocturnal (but not morning) ghrelin secretion.