The aim of the study is to find possible explanations for vanishing juvenile hypoglycemia in growth hormone receptor deficiency (GHRD) in human patients and animal models. We reviewed parameters of glucose metabolism in distinct age groups into two human cohorts (Israeli and Ecuadorian) of Laron syndrome (LS) patients, a mouse model (Ghr-KO mouse) and provided additional data for a porcine model (GHR-KO pig). Juvenile hypoglycemia is a common symptom of GHRD and vanishes in adulthood. In the Israeli cohort, developing metabolic syndrome is associated with decreasing insulin sensitivity, insulinopenia and glucose intolerance, and increasing glucose levels with age. In the Ecuadorian patients and both animal models, insulin sensitivity is preserved or even enhanced. Alterations in food intake and energy consumption do not explain the differences in glucose levels; neither is the accumulation of body fat associated with negative effects in the Ecuadorian cohort nor in the animal models. A reduced beta-cell mass and resulting insulin secretory capacity is common and leads to glucose intolerance in Ghr-KO mice, while glucose tolerance is preserved in Ecuadorian patients and the GHR-KO pig. In human patients and the GHR-KO pig, a simultaneous occurrence of normoglycemia with the onset of puberty is reported. Reduced gluconeogenesis in GHRD is discussed to cause juvenile hypoglycemia and a counter-regulatory stimulation of gluconeogenesis can be hypothesized. A coherent study assessing endogenous glucose production and beta-cell capacity in the hypoglycemic and normoglycemic age group is needed. This can be performed in GHR-KO pigs, including castrated animals.
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Arne Hinrichs, Simone Renner, Martin Bidlingmaier, John J Kopchick, and Eckhard Wolf
Annamaria Colao, Rosario Pivonello, Renata S Auriemma, Maria Cristina De Martino, Martin Bidlingmaier, Francesco Briganti, Fabio Tortora, Pia Burman, Ione A Kourides, Christian J Strasburger, and Gaetano Lombardi
Objective: We aimed to investigate the efficacy of pegvisomant in patients with acromegaly resistant to long-term (≧ 24-month), high-dose treatment with octreotide-LAR (40 mg/month) or lanreotide (120 mg/month).
Design: This was an open, prospective study.
Subjects and Methods: We studied 16 patients with acromegaly (nine women; aged 28–61 years). The main outcome measures were IGF-I levels, blood pressure, glucose tolerance and safety (liver function and tumor size). Pegvisomant was given at doses of 10–40 mg s.c. daily. Dose titration was performed every month by IGF-I assay.
Results: Three patients spontaneously stopped pegvisomant treatment after 6–9 months because of poor compliance; from the measurement of serum pegvisomant, another patient was found not to inject herself properly. After 6 months, IGF-I levels decreased by 63 ± 19% (767.8 ± 152.9 vs 299.8 ± 162.9 μg/l, P < 0.0001, t-test); serum IGF-I levels normalized in 57%. After 12 months, IGF-I levels normalized in nine (75%) patients and were reduced by over 50% in another three (25%). The mean tumor volume remained stable during the study (1198 ± 1234 vs 1196 ± 1351 mm3, P = 0.37): it did not change ( ± 25% vs basal) in nine patients, increased by 39.4% and 40.8% in two and decreased by 30.8–46.5% in four. The total/high-density lipoprotein (HDL):cholesterol ratio (from 4.4 ± 1.0 to 3.7 ± 0.6, P= 0.0012), glucose levels (from 5.6 ± 1.2 to 4.4 ± 1.4 mmol/l, P = 0.026), insulin levels (from 12.4 ± 6.7 to 8.1 ± 3.0 mUl/l, P = 0.0023) and homeostasis model assessment (HOMA) index (from 3.4 ± 2.1 to 1.9 ± 1.0, P = 0.0017) decreased.
Conclusions: Treatment for 12 months with pegvisomant normalized IGF-I levels, and improved cardiovascular risk parameters and insulin sensitivity in patients with acromegaly resistant to long-term, high-dose treatment with somatostatin analogs. The tolerance of treatment was good.
Dirk Weismann, Mirko Peitzsch, Anna Raida, Aleksander Prejbisz, Maria Gosk, Anna Riester, Holger S Willenberg, Reiner Klemm, Georg Manz, Timo Deutschbein, Matthias Kroiss, Roland Därr, Martin Bidlingmaier, Andrzej Januszewicz, Graeme Eisenhofer, and Martin Fassnacht
Background
Reports conflict concerning measurements of plasma metanephrines (MNs) for diagnosis of pheochromocytomas/paragangliomas (PPGLs) by immunoassays compared with other methods. We aimed to compare the performance of a commercially available enzyme-linked immunoassay (EIA) kit with liquid chromatography–tandem mass spectrometric (LC–MS/MS) measurements of MNs to diagnose PPGLs.
Methods
In a substudy of a prospective, multicenter trial to study the biochemical profiles of monoamine-producing tumors, we included 341 patients (174 males and 167 females) with suspected PPGLs (median age 54 years), of whom 54 had confirmed PPGLs. Plasma MNs were measured by EIA and LC–MS/MS, each in a specialized laboratory.
Results
Plasma normetanephrine (NMN) and MN were measured 60 and 39% lower by EIA than by LC–MS/MS. Using upper cut-offs stipulated for the EIA, diagnostic sensitivity was only 74.1% at a specificity of 99.3%. In contrast, use of similar cut-offs for MN and overall lower age-adjusted cut-offs for NMN measured by LC–MS/MS returned a diagnostic sensitivity and specificity of 98.1 and 99.7%. Areas under receiver-operating characteristic curves, nevertheless, indicated comparable diagnostic performance of the EIA (0.993) and LC–MS/MS (0.985). Diagnostic sensitivity for the EIA increased to 96.2% with a minimal loss in specificity (95.1%) following use of cut-offs for the EIA adapted to correct for the negative bias.
Conclusions
The EIA underestimates plasma MNs and diagnostic sensitivity is poor using commonly stipulated cut-offs, resulting in a high risk for missing patients with PPGLs. Correction of this shortcoming can be achieved by appropriately determined cut-offs resulting in comparable diagnostic performance of EIA and LC–MS/MS assays.
Anke Hannemann, Christa Meisinger, Martin Bidlingmaier, Angela Döring, Barbara Thorand, Margit Heier, Petra Belcredi, Karl-Heinz Ladwig, Henri Wallaschofski, Nele Friedrich, Sabine Schipf, Jan Lüdemann, Rainer Rettig, Jörg Peters, Henry Völzke, Jochen Seissler, Felix Beuschlein, Matthias Nauck, and Martin Reincke
Objective
The aim of this study was to analyze the potential association of the plasma aldosterone concentration (PAC) with the metabolic syndrome (MetS) and its components in two German population-based studies.
Methods
We selected 2830 and 2901 participants (31–80 years) from the follow-ups of the Study of Health in Pomerania (SHIP)-1 and the Cooperative Health Research in the Region of Augsburg (KORA) F4 respectively. MetS was defined as the presence of at least three out of the following five criteria: waist circumference ≥94 cm (men (m)) and ≥80 cm (women (w)); high-density lipoprotein (HDL) cholesterol <1.0 mmol/l (m) and <1.3 mmol/l (w); blood pressure ≥130/85 mmHg or antihypertensive treatment; non-fasting glucose (SHIP-1) ≥8 mmol/l, fasting glucose (KORA F4) ≥5.55 mmol/l or antidiabetic treatment; non-fasting triglycerides (SHIP-1) ≥2.3 mmol/l, fasting triglycerides (KORA F4) ≥1.7 mmol/l, or lipid-lowering treatment. We calculated logistic regression models by comparing the highest study- and sex-specific PAC quintiles versus all lower quintiles.
Results
MetS was common with 48.1% (m) and 34.8% (w) in SHIP-1 and 42.7% (m) and 27.5% (w) in KORA F4. Our logistic regression models revealed associations of PAC with MetS, elevated triglycerides, and decreased HDL cholesterol in SHIP-1 and KORA F4.
Conclusions
Our findings add to the increasing evidence supporting a relation between aldosterone and MetS and suggest that aldosterone may be involved in the pathophysiology of MetS and lipid metabolism disorders.
Frederick Vogel, Leah Braun, German Rubinstein, Stephanie Zopp, Sarina Benedix, Holger Schneider, Katrin Ritzel, Katharina Schilbach, Ralf Schmidmaier, Felix Beuschlein, Martin Bidlingmaier, and Martin Reincke
Background
Glucocorticoid excess leads to muscle atrophy and weakness in patients with endogenous Cushing’s syndrome. Insulin-like growth factor I (IGF-I) is known to have protective effects on muscle loss. We hypothesized that individual serum IGF-I concentrations might be predictive for long-term myopathy outcome in Cushing’s syndrome.
Patients and methods
In a prospective longitudinal study of 31 patients with florid Cushing’s syndrome, we analyzed IGF-I and IGF binding protein 3 (IGFBP 3) concentrations at the time of diagnosis and following surgical remission over a period of up to 3 years. We assessed muscle strength by grip strength measurements using a hand grip dynamometer and muscle mass by bio-impedance measurements.
Findings
Individual serum IGF-I concentrations in the postoperative phase were strongly predictive of long-term grip strength outcome (rs = 0.696, P ≤ 0.001). Also, lower IGF-I concentrations were associated with a lower muscle mass after 3 years (rs = 0.404, P = 0.033). While patients with high IGF-I s.d. scores (SDS; >1.4) showed an improvement in grip strength within the follow-up period (P = 0.009), patients with lower IGF-I SDS (≤−0.4) had a worse outcome with persisting muscle dysfunction. In contrast, preoperative IGF-I concentrations during the florid phase of Cushing’s syndrome did not predict long-term muscle function outcome (rs = 0.285, P = 0.127).
Conclusion
Lower individual IGF-I concentrations 6 months after curative surgery for Cushing’s syndrome are associated with adverse long-term myopathy outcome and IGF-I might be essential for muscle regeneration in the early phase after correction of hypercortisolism.
Charlotte Michaela Fries, Yoon Ju Bae, Nada Rayes, Benjamin Sandner, Berend Isermann, Michael Stumvoll, Valentina Fagotto, Martin Reincke, Martin Bidlingmaier, Vogel Mandy, Jürgen Kratzsch, and Wiebke Kristin Fenske
Objective
Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) has become state of the art for the quantitative analysis of steroid hormones. Although method comparisons show that aldosterone measurement using LC-MS/MS yields considerably lower levels than immunoassays (IAs), method-specific cutoff values for primary aldosteronism (PA) are largely missing. Objective of this study was to analyze the diagnostic accuracy of proposed LC-MS/MS-specific cutoff values for the saline infusion test (SIT).
Design and methods
From 2016 to 2019, 104 consecutive patients suspected of PA underwent the SIT and captopril challenge test in the tertiary medical center at the University Hospital of Leipzig, Germany. Patients with positive case confirmation underwent adrenal imaging and adrenal venous sampling for subtype classification.
Results
Overall, proposed assay-specific PACLC-MS/MS cutoff values for the SIT achieved higher diagnostic accuracy than established PACIA values with a sensitivity and specificity of 87.5% (95% CI: 71.0–96.5) and 97% (95% CI: 89.6–99.6) for a cutoff of 120 pmol/L and 93.8% (95% CI: 79.2–99.2) and 92.5% (95% CI: 83.4–97.5) for a cutoff of 94 pmol/L. The most accurate post-SIT PACLC-MS/MS cutoff value in this study was 83 pmol/L, yielding a sensitivity and specificity of 96.9% (95% CI: 83.8–99.9) and 92.5% (95% CI: 83.4–97.5), respectively.
Conclusions
The present data confirm the need for the implication of lower method-specific aldosterone cutoff values for the diagnosis of PA with LC-MS/MS based aldosterone measurement.
Matthias K Auer, James M Hawley, Christian Lottspeich, Martin Bidlingmaier, Andrea Sappl, Hanna F Nowotny, Lea Tschaidse, Marcus Treitl, Martin Reincke, Brian G Keevil, and Nicole Reisch
Objective
Differentiation of an adrenal from an ovarian source of hyperandrogenemia can be challenging. Recent studies have highlighted the importance of 11-oxygenated C19 steroids to the androgen pool in humans. The aim of this study was to confirm the origin of 11-oxygenated androgens in females and to explore their potential use in the diagnostics of hyperandrogenic disorders.
Methods
We measured testosterone and its precursors (dehydroepiandrosterone-sulfate and androstenedione) and 11-oxygenated androgens (11β-hydroxyandrostenedione (11-OHA4) and 11-ketotestosterone (11-KT)) in the periphery, adrenal and ovarian veins in four different cases of hyperandrogenism in females (polycystic ovary syndrome (PCOS), primary bilateral macronodular adrenal hyperplasia, Sertoli–Leydig cell tumor and ovarian steroid cell tumor).
Results
Two patients demonstrate excessive testosterone secretion in neoplastic ovarian tumors which was not paralleled by a significant secretion of 11-oxygenated androgens as determined by adrenal and ovarian vein sampling. In androgen-secreting bilateral adrenal macronodular hyperplasia, steroid profiles were characterized by elevated 11-KT and 11-OHA4 concentrations in adrenal veins and the periphery. In the patient with PCOS, peripheral 11-KT concentrations were slightly elevated in comparison to the other patients, but the 11-KT and 11-OHA4 concentrations were comparable in ovarian veins and in the periphery.
Conclusion
This study confirms that 11-OHA4 and 11-KT are not biosynthesized by the ovary. We propose that the testosterone/11-KT ratio as well as 11-OHA4 could help identify predominant adrenal androgen excess and distinguish neoplastic and non-neoplastic ovarian androgen source.
Significance statement
This study confirms that 11β-hydroxyandrostenedione (11-OHA4) and 11-ketotestosterone (11-KT) are not biosynthesized by the human ovary. We propose that the testosterone/11-KT ratio as well as 11-OHA4 could help to identify predominant adrenal androgen excess and distinguish neoplastic and non-neoplastic ovarian androgen source.
Christian J Strasburger, Peter Vanuga, Juraj Payer, Marija Pfeifer, Vera Popovic, László Bajnok, Miklós Góth, Veˇra Olšovská, L‘udmila Trejbalová, Janos Vadasz, Eyal Fima, Ronit Koren, Leanne Amitzi, Martin Bidlingmaier, Oren Hershkovitz, Gili Hart, and Beverly M K Biller
Objective
Growth hormone (GH) replacement therapy currently requires daily injections, which may cause distress and low compliance. C-terminal peptide (CTP)-modified growth hormone (MOD-4023) is being developed as a once-weekly dosing regimen in patients with GH deficiency (GHD). This study’s objective is to evaluate the safety, pharmacokinetics (PK), pharmacodynamics (PD) and efficacy of MOD-4023 administered once-weekly in GHD adults.
Design
54 adults with GHD currently treated with daily GH were normalized and randomized into 4 weekly dosing cohorts of MOD-4023 at 18.5%, 37%, 55.5% or 123.4% of individual cumulative weekly molar hGH dose. The study included 2 stages: Stage A assessed the effectiveness and PK/PD profiles of the 4 dosing regimens of MOD-4023. Stage B was an extension period of once-weekly MOD-4023 administration (61.7% molar hGH content) to collect further safety data and confirm the results from Stage A.
Results
Dose-dependent response was observed for both PK and PD data of weekly MOD-4023 treatment. Insulin-like growth factor I (IGF-I) SDS levels were maintained within normal range. The 18.5% cohort was discontinued due to low efficacy. MOD-4023 was well tolerated and exhibited favorable safety profile in all dose cohorts. The reported adverse events were consistent with known GH-related side effects.
Conclusions
Once-weekly MOD-4023 administration in GHD adults was found to be clinically effective while maintaining a favorable safety profile and may obviate the need for daily injections. Weekly GH injections may improve compliance and overall outcome. The promising results achieved in this Phase 2 study led to a pivotal Phase 3 trial, which is currently ongoing.
Christian J Strasburger, Niki Karavitaki, Sylvère Störmann, Peter J Trainer, Ilonka Kreitschmann-Andermahr, Michael Droste, Márta Korbonits, Berit Feldmann, Kathrin Zopf, Violet Fazal Sanderson, David Schwicker, Dana Gelbaum, Asi Haviv, Martin Bidlingmaier, and Nienke R Biermasz
Background
Long-acting somatostatin analogues delivered parenterally are the most widely used medical treatment in acromegaly. This patient-reported outcomes survey was designed to assess the impact of chronic injections on subjects with acromegaly.
Methods
The survey was conducted in nine pituitary centres in Germany, UK and The Netherlands. The questionnaire was developed by endocrinologists and covered aspects of acromegaly symptoms, injection-related manifestations, emotional and daily life impact, treatment satisfaction and unmet medical needs.
Results
In total, 195 patients participated, of which 112 (57%) were on octreotide (Sandostatin LAR) and 83 (43%) on lanreotide (Somatuline Depot). The majority (>70%) of patients reported acromegaly symptoms despite treatment. A total of 52% of patients reported that their symptoms worsen towards the end of the dosing interval. Administration site pain lasting up to a week following injection was the most frequently reported injection-related symptom (70% of patients). Other injection site reactions included nodules (38%), swelling (28%), bruising (16%), scar tissue (8%) and inflammation (7%). Injection burden was similar between octreotide and lanreotide. Only a minority of patients received injections at home (17%) and 5% were self-injecting. Over a third of patients indicated a feeling of loss of independence due to the injections, and 16% reported repeated work loss days. Despite the physical, emotional and daily life impact of injections, patients were satisfied with their treatment, yet reported that modifications that would offer major improvement over current care would be ‘avoiding injections’ and ‘better symptom control’.
Conclusion
Lifelong injections of long-acting somatostatin analogues have significant burden on the functioning, well-being and daily lives of patients with acromegaly.
Katharina Schilbach, Christina Gar, Andreas Lechner, Shiva Sophia Nicolay, Laura Schwerdt, Michael Haenelt, Jakob Dal, Jens-Otto Lunde Jørgensen, Sylvère Störmann, Jochen Schopohl, and Martin Bidlingmaier
Objective
Growth hormone (GH) nadir (GHnadir) during oral glucose tolerance test (OGTT) is an important tool in diagnosing acromegaly, but data evaluating the need to adjust cut-offs to biological variables utilizing today's assay methods are scarce. We therefore investigated large cohorts of healthy subjects of both sexes to define normal GHnadir concentrations for a modern, sensitive, 22 kD-GH-specific assay.
Design
Multicenter study with prospective and retrospective cohorts (525 healthy adults: 405 females and 120 males).
Methods
GH concentrations were measured by the IDS-iSYS immunoassay after oral application of 75 g glucose.
Results
GHnadir concentrations (µg/L) were significantly higher in lean and normal weight subjects (group A) compared to overweight and obese subjects (group B); (males (M): A vs B, mean: 0.124 vs 0.065, P = 0.0317; premenopausal females without estradiol-containing OC (OC-EE) (FPRE): A vs B, mean: 0.179 vs 0.092, P < 0.0001; postmenopausal women (FPOST): A vs B, mean: 0.173 vs 0.078, P < 0.0061). Age, glucose metabolism and menstrual cycle had no impact on GHnadir. However, premenopausal females on OC-EE (FPREOC) exhibited significantly higher GHnadir compared to all other groups (all P < 0.0001). BMI had no impact on GHnadir in FPREOC (A vs B, mean: 0.624 vs 0.274, P = 0.1228).
Conclusions
BMI, sex and OC-EE intake are the major determinants for the GHnadir during OGTT in healthy adults. Using a modern sensitive GH assay, GHnadir concentrations in healthy subjects are distinctly lower than cut-offs used in previous guidelines for diagnosis and monitoring of acromegaly.