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Nèle F Lenders, Ann I McCormack, and Ken K Y Ho

Gonadal steroids modulate the effects of GH, with oestrogens attenuating and androgens augmenting GH action. Whether these divergent effects influence the clinical manifestation, management and prognosis of acromegaly have not been carefully reviewed. This review examines whether there is a gender difference in epidemiology, presentation, quality of life (QoL), morbidity, treatments and mortality of acromegaly. Acromegaly is more common in women who present at an older age with longer diagnostic delay. At presentation, women have a higher GH relative to IGF-1 level than men. QoL is more adversely affected in women both before and after treatment. Prevalence of hypertension and diabetes are greater in women than in men with acromegaly. Treatment outcomes with SSAs are comparable between sexes, but women may require a higher dose of pegvisomant for equivalent response. Mortality in untreated acromegaly is more profoundly affected in women; however, improved treatments in recent decades have resulted in normalisation of standard mortality ratios in both sexes. We conclude that gender does matter in the management of acromegaly, with women presenting later in life, with greater diagnostic delay, higher prevalence of comorbidities and experiencing worse QoL.

Free access

Rolf H H Groenwold and Olaf M Dekkers

The results of observational studies of causal effects are potentially biased due to confounding. Various methods have been proposed to control for confounding in observational studies. Eight basic aspects of confounding adjustment are described, with a focus on correction for confounding through covariate adjustment using regression analysis. These aspects should be considered when planning an observational study of causal effects or when assessing the validity of the results of such a study.

Restricted access

Mirko Peitzsch, Denise Kaden, Christina Pamporaki, Katharina Langton, Georgiana Constantinescu, Catleen Conrad, Stephanie Fliedner, Richard O Sinnott, Aleksander Prejbisz, Roland Därr, Jacques W M Lenders, Michael Bursztyn, and Graeme Eisenhofer

Objective

Sympathoadrenal activity is decreased during overnight rest. This study assessed whether urinary-free normetanephrine, metanephrine and methoxytyramine in overnight/first-morning urine collections might offer an alternative to measurements in 24-h collections or plasma for diagnosis of pheochromocytoma and paraganglioma (PPGL).

Design and methods

Prospective multicenter cross-sectional diagnostic study involving 706 patients tested for PPGL, in whom tumors were confirmed in 79 and excluded in 627 after follow-up. Another 335 age- and sex-matched volunteers were included for reference purposes. Catecholamines and their free O-methylated metabolites were measured in 24-h collections divided according to waking and sleeping hours and normalized to creatinine. Plasma metabolites from blood sampled after supine rest were measured for comparison.

Results

Urinary outputs of norepinephrine, normetanephrine, epinephrine and metanephrine in the reference population were respectively 50 (48–52)%, 35 (32–37)%, 76 (74–78)% and 15 (12–17)% lower following overnight than daytime collections. Patients in whom PPGLs were excluded showed 28 (26–30)% and 6 (3–9)% day-to-night falls in normetanephrine and metanephrine, while patients with PPGLs showed no significant day-to-night falls in metabolites. Urinary methoxytyramine was consistently unchanged from day to night. According to receiver-operating characteristic curves, diagnostic accuracy of metabolite measurements in overnight/first-morning urine samples did not differ from measurements in 24-h urine collections, but was lower for both than for plasma. Using optimized reference intervals, diagnostic specificity was higher for overnight than daytime collections at similar sensitivities.

Conclusions

Measurements of urinary-free catecholamine metabolites in first-morning/overnight urine collections offer an alternative for diagnosis of PPGL to 24-h collections but remain less accurate than plasma measurements.

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S Cambos, K Mohammedi, F Castinetti, C Saie, J Young, P Chanson, and A Tabarin

Objective

Cushing’s disease (CD) may recur despite corticotropic insufficiency (COI) following pituitary surgery. The predictive value of the desmopressin test (DT) for recurrence in this setting remains controversial. We have evaluated whether the disappearance of the response to DT predicts a low probability recurrence in a large cohort of patients with post-operative COI.

Design

Multicentre retrospective study.

Methods

Ninety-five patients with CD (women 82%, age 41 ± 14 years), responding preoperatively to DT and with early post-operative COI (08 00 am cortisol: <138 nmol/L), underwent a DT within 3 months post-surgery. Association between DT findings and the prediction of recurrence was tested using regression and ROC analyses.

Results

Recurrence occurred in 17/95 patients within 29 to 91 months. The cortisol peak (327, 95% CI (237–417) vs 121 (79–164) nmol/L, P = 0.0001) and absolute increment during DT (208 (136–280) vs 56 (22–90) nmol/L, P = 0.005) were greater in the recurrence vs remission group. Cortisol peak (AUC: 0.786 (0.670–0.902)) and increment (0.793 (0.672–0.914)) yielded a higher prognostic performance for recurrence than did the early post-operative 08 00 am cortisol (0.655 (0.505–0.804)). In the context of COI, cortisol peak >100 nmol/L and increment >30 nmol/L had a high negative predictive value (94, 95% CI (88–100) and 94, (88–100), respectively). Patients with a cortisol peak ≤100 nmol/L (vs >100) or an increment ≤30 nmol/L (vs >30) were less likely to have CD recurrence (odds ratios: 0.12, 95% CI (0.03–0.41) and 0.11 (0.02–0.36), respectively).

Conclusion

The disappearance of the response to the post-operative DT was independently associated with a lower odds of CD recurrence and offers an incremental prognostic value, which may help to stratify patients with COI and refine their follow-up according to the risk of recurrence.

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Nikolaos Kyriakakis, Nikoletta Pechlivani, Julie Lynch, Natalie Oxley, Fladia Phoenix, Khyatisha Seejore, Steve M Orme, Ramzi Ajjan, and Robert D Murray

Objective

There remains increased cardiovascular mortality in patients with acromegaly. This study aims to evaluate whether GH/IGF-1 excess increases vascular disease by adversely affecting fibrin network characteristics.

Design

Cross-sectional study in 40 patients with acromegaly (21 males, age 53 ± 13 years) and 40 age/gender-matched controls.

Methods

Clot structure was analysed using a validated turbidimetric assay and fibrin networks were visualised by laser scanning confocal microscopy (LSCM). Metabolic profile parameters, body composition, plasma fibrinogen and PAI-1 were also assessed.

Results

Twenty-two patients had active acromegaly and 18 were in remission. There was no difference in qualitative patient characteristics between the two groups. Both groups had less favourable body composition and cardiovascular risk profile compared with controls. Despite no difference in clot formation and lysis parameters between the two patient groups, active disease patients had higher fibrinogen and clot maximum absorbance compared with controls, after adjusting for BMI (3.8 ± 0.2 vs 2.6 ± 0.2 mg/mL, P < 0.001; and 0.39 ± 0.02 vs 0.33 ± 0.01 arbitrary units, P = 0.03, respectively). Patients in remission had higher fibrinogen compared with controls following adjustment for BMI (3.3 ± 0.2 vs 2.6 ± 0.2 mg/mL, P = 0.02) but not clot maximum absorbance (0.35 ± 0.03 vs 0.33 ± 0.02 arbitrary units, P = 0.6). LSCM showed increased fibrin network density only in active disease patients, consistent with turbidimetric analysis. In addition to active disease, BMI, fat mass and skinfold thickness were associated with higher clot density and longer lysis time.

Conclusions

Patients with active acromegaly have more compact clots, thus conferring increased thrombosis risk. Prothrombotic fibrin networks may represent one mechanism for enhanced vascular risk in active acromegaly.

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Connor Wright, Patrick O’Day, Mohammed Alyamani, Nima Sharifi, and Richard J Auchus

Context

The human adrenal is the dominant source of androgens in castration-resistant prostate cancer (CRPC) and classic 21-hydroxylase deficiency (21OHD). Abiraterone, derived from the prodrug abiraterone acetate (AA), inhibits the activity of cytochrome P450 17-hydroxylase/17,20-lyase (CYP17A1), the enzyme required for all androgen biosynthesis. AA treatment effectively lowers testosterone and androstenedione in 21OHD and CRPC patients. The 11-oxygenated androgens are major adrenal-derived androgens, yet little is known regarding the effects of AA administration on 11-oxygenated androgens.

Objective

To test the hypothesis that AA therapy decreases 11-oxygenated androgens.

Design

Samples were obtained from 21OHD or CRPC participants in AA or AA plus prednisone (AAP)-treatment studies, respectively.

Methods

We employed liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure the 11-oxygenated androgens, 11β-hydroxyandrostenedione, 11-ketoandrostenedione, 11β-hydroxytestosterone, and 11-ketotestosterone, in plasma or serum samples from six 21OHD and six CRPC patients before and after treatment with AA or AAP, respectively.

Results

In CRPC patients, administration of AAP (1000 mg/day AA with prednisone and medical castration) lowered all four 11-oxygenated androgens to below the lower limits of quantitation (<0.1–0.3 nmol/L), equivalent to 64–94% reductions from baseline. In 21OHD patients, administration of AA (100–250 mg/day for 6 days) reduced all 11-oxygenated androgens by on average 56–77% from baseline.

Conclusions

We conclude that AA and AAP therapies markedly reduce the production of the adrenal-derived 11-oxygenated androgens, both in patients with high (21OHD) or normal (CRPC) 11-oxygenated androgens at baseline, respectively. Reduction of 11-oxygenated androgens is an important aspect of AA and AAP pharmacology.

Open access

A Veltroni, E Cosaro, F Spada, N Fazio, A Faggiano, A Colao, S Pusceddu, M C Zatelli, D Campana, A Piovesan, A Pia, E M Grossrubatscher, A Filice, A Bianchi, P Razzore, M Toaiari, S Cingarlini, L Landoni, R Micciolo, and M V Davì

Introduction

Management of malignant insulinomas is challenging due to the need to control both hypoglycaemic syndrome and tumor growth. Literature data is limited to small series.

Aim of the study

To analyze clinico-pathological characteristics, treatments and prognosis of patients with malignant insulinoma.

Materials and methods

Multicenter retrospective study on 31 patients (male: 61.3%) diagnosed between 1988 and 2017.

Results

The mean age at diagnosis was 48 years. The mean NET diameter was 41 ± 31 mm, and 70.8% of NETs were G2. Metastases were widespread in 38.7%, hepatic in 41.9% and only lymph nodal in 19.4%. In 16.1% of the cases, the hypoglycaemic syndrome occurred after 46 ± 35 months from the diagnosis of originally non-functioning NET, whereas in 83.9% of the cases it led to the diagnosis of NET, of which 42.3% with a mean diagnostic delay of 32.7 ± 39.8 months. Surgical treatment was performed in 67.7% of the cases. The 5-year survival rate was 62%. Overall survival was significantly higher in patients with Ki-67 ≤10% (P = 0.03), insulin level <60 µU/mL (P = 0.015) and in patients who underwent surgery (P = 0.006). Peptide Receptor Radionuclide Therapy (PRRT) was performed in 45.1%, with syndrome control in 93% of patients.

Conclusions

Our study includes the largest series of patients with malignant insulinoma reported to date. The hypoglycaemic syndrome may occur after years in initially non-functioning NETs or be misunderstood with delayed diagnosis of NETs. Surgical treatment and Ki67 ≤10% are prognostic factors associated with better survival. PPRT proved to be effective in the control of hypoglycaemia in majority of cases.

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S H Donze, L Damen, E F Mahabier, and A C S Hokken-Koelega

Objective

Children with Prader–Willi syndrome (PWS) have mild to moderate cognitive impairment. Short-term studies showed positive effects of growth hormone (GH) on cognitive development. This study investigated the effects of 8 years of GH on cognitive development in children with PWS. We also investigated whether starting GH during infancy results in higher cognitive functioning after 8 years of GH.

Design

Longitudinal study in 43 children with PWS during 8 years of GH (median age at GH start 8.1 years). Cognitive functioning after 8 years was compared to another group of 22 children with PWS (median age at GH start 1.4 years).

Methods

Cognitive functioning was measured by Wechsler Intelligence Scale for Children. Vocabulary, Similarities and Block Design subtests were expressed as standard deviation scores (SDS) and total IQ (TIQ) calculated.

Results

Estimated mean (95%CI) Block Design SDS changed from −2.2 (−2.6; −1.8) at GH start to −1.8 (−2.2; −1.4) after 8 years of GH (P = 0.18), similarly SDS from −1.5 (−2.1; −0.9) to −1.3 (−1.9; −0.7, P = 0.66) and TIQ from 66 (60; 72) to 69 (63; 75, P = 0.57). Vocabulary SDS remained similar, being −1.9 (−2.3; −1.4) at GH start and −1.9 (−2.4; −1.5) after 8 years (P = 0.85). After 8 years of GH Vocabulary, SDS and TIQ were higher in the children who started GH during infancy, compared to those who started GH later in childhood (P < 0.01, P = 0.04, respectively).

Conclusions

Cognitive functioning in children with PWS remains similar during long-term GH and develops at the same pace as healthy peers.

Open access

Andreas Stomby, Julia Otten, Mats Ryberg, Ruth Andrew, Brian R Walker, and Tommy Olsson

Context

Altered tissue-specific glucocorticoid metabolism has been described in uncomplicated obesity and type 2 diabetes. We hypothesized that weight loss induced by diet and exercise, which has previously been shown to reverse abnormal cortisol metabolism in uncomplicated obesity, also normalizes cortisol metabolism in patients with type 2 diabetes.

Objective

Test the effects of a diet intervention with added exercise on glucocorticoid metabolism.

Design

Two groups followed a Paleolithic diet (PD) for 12 weeks with added 180 min of structured aerobic and resistance exercise per week in one randomized group (PDEX).

Setting

Umeå University Hospital.

Participants

Men and women with type 2 diabetes treated with lifestyle modification ± metformin were included. Twenty-eight participants (PD, n = 15; PDEX, n = 13) completed measurements of glucocorticoid metabolism.

Main outcome measures

Changes in glucocorticoid metabolite levels in 24-h urine samples, expression of HSD11B1 mRNA in s.c. adipose tissue and conversion of orally administered cortisone to cortisol measured in plasma. Body composition and insulin sensitivity were measured using a hyperinsulinemic-euglycemic clamp, and liver fat was measured by magnetic resonance spectroscopy.

Results

Both groups lost weight and improved insulin sensitivity. Conversion of orally taken cortisone to plasma cortisol and the ratio of 5α-THF + 5β-THF/THE in urine increased in both groups.

Conclusions

These interventions caused weight loss and improved insulin sensitivity with concomitant increases in the conversion of cortisone to cortisol, which is an estimate of hepatic HSD11B1 activity. This suggests that dysregulation of liver glucocorticoid metabolism in these patients is a consequence rather than a cause of metabolic dysfunction.

Free access

John P H Wilding

Endocrine disorders such as Cushing’s syndrome and hypothyroidism may cause weight gain and exacerbate metabolic dysfunction in obesity. Other forms of endocrine dysfunction, particularly gonadal dysfunction (predominantly testosterone deficiency in men and polycystic ovarian syndrome in women), and abnormalities of the hypothalamic-pituitary-adrenal axis, the growth hormone-IGF-1 system and vitamin D deficiency are common in obesity. As a result, endocrinologists may be referred people with obesity for endocrine testing and asked to consider treatment with various hormones. A recent systematic review and associated guidance from the European Society of Endocrinology provide a useful evidence summary and clear guidelines on endocrine testing and treatment in people with obesity. With the exception of screening for hypothyroidism, most endocrine testing is not recommended in the absence of clinical features of endocrine syndromes in obesity, and likewise hormone treatment is rarely needed. These guidelines should help reduce unnecessary endocrine testing in those referred for assessment of obesity and encourage clinicians to support patients with their attempts at weight loss, which if successful has a good chance of correcting any endocrine dysfunction.