Hair Glucocorticoids as a Biomarker for Endogenous Cushing's Syndrome: Validation in Two Independent Cohorts.

BACKGROUND/AIMS: The current diagnostic workup of Cushing's syndrome (CS) requires various tests which only capture short-term cortisol exposure, whereas patients with endogenous CS generally have elevated cortisol levels over longer periods of time. Scalp hair assessment has emerged as a convenient test in capturing glucocorticoid concentrations over long periods of time. The aim of this multicenter, multinational, prospective, case-control study was to evaluate the diagnostic efficacy of scalp hair glucocorticoids in screening of endogenous CS. METHODS: We assessed the diagnostic performances of hair cortisol (HairF), hair cortisone (HairE), and the sum of both (sumHairF+E), as measured by a state-of-the-art LC-MS/MS technique, in untreated patients with confirmed endogenous CS (n = 89) as well as in community controls (n = 295) from the population-based Lifelines cohort study. RESULTS: Both glucocorticoids were significantly elevated in CS patients when compared to controls. A high diagnostic efficacy was found for HairF (area under the curve 0.87 [95% CI: 0.83-0.92]), HairE (0.93 [0.89-0.96]), and sumHairF+E (0.92 [0.88-0.96]) (all p < 0.001). The participants were accurately classified at the optimal cutoff threshold in 86% of the cases (81% sensitivity, 88% specificity, and 94% negative predictive value [NPV]) by HairF, in 90% of the cases (87% sensitivity, 90% specificity, and 96% NPV) by HairE, and in 87% of the cases (86% sensitivity, 88% specificity, and 95% NPV) by the sumHairF+E. HairE was shown to be the most accurate in differentiating CS patients from controls. CONCLUSION: Scalp hair glucocorticoids, especially hair cortisone, can be seen as a promising biomarker in screening for CS. Its convenience in collection and workup additionally makes it feasible for first-line screening.

Frequency of clinical signs in patients with Cushing's syndrome and mild autonomous cortisol secretion: overlap is common.

BACKGROUND: Cushing's syndrome (CS) can be difficult to diagnose. A timely diagnosis, however, is the cornerstone for targeted treatment, to reduce morbidity and mortality. One reason for the difficulties to identify early on patients with CS might be the presence of a mild phenotype. The aim of the study was to classify the phenotypic landscape of CS. We studied patients with overt CS and mild autonomous cortisol secretion (MACS). METHOD: The study was part of the German Cushing's registry. Patients were prospectively included at time of diagnosis and the number of comorbidities and clinical signs and symptoms were assessed in a standardized fashion. One hundred twenty-nine patients with CS (pituitary CS, n = 85, adrenal CS, n = 32, ectopic CS, n = 12, respectively) and 48 patients with MACS were included. Patients with clinical signs and/or comorbidities typical for CS and at least 2 pathological screening tests were classified as having CS. Patients with a 1 mg low-dose-dexamethasone-suppression test above 1.8 µg/dL without being clinically overt CS were classified as having MACS. RESULTS: On average, patients with CS had 2 comorbidities (range 1-3) at time of diagnosis (pituitary CS: 2 [1-3], adrenal CS: 3 [2-4], ectopic CS: 3 [2-4]). Patients with MACS, however, had 3 comorbidities (range 2-3). Hypertension was the most common comorbidity in all subtypes of CS (78%-92%) and in patients with MACS (87%). Of a total of 11 clinical signs, patients with CS had on average 5 with 28% of patients having between 0 and 3 clinical signs, 50% 4-7 signs, and 22% more than 7 clinical signs. Patients with MACS had on average 2 clinical signs (range 1-3) at time of diagnosis. CONCLUSION: The phenotypic landscape of CS is quite variable. The frequency of comorbidities is similar between patients with CS and MACS. A relevant number of patients with overt CS have just a few clinical signs. There is also an overlap in frequency of symptoms and clinical signs between patients with CS and MACS. According to the current guidelines, 96% of our patients with MACS fall into the category "consideration of adrenalectomy". This should be kept in mind when making treatment decisions in the latter group of patients.

Biochemical Control in Cushing's syndrome: Outcomes of the treatment in a large single center cohort.

BACKGROUND: Normalization of hypercortisolism is essential to reduce morbidity and mortality in patients with Cushing's syndrome (CS). The aim of this analysis was to assess biochemical control rates in patients with Cushing's disease (CD), ectopic Cushing's syndrome (ECS) and adrenal Cushing's syndrome (ACS). METHODS: Patients with confirmed CS (n= 296) treated in a single tertiary care center were retrospectively analysed (185 CD, 27 ECS, 84 uni- and bilateral ACS). RESULTS: Firstline treatment led to biochemical control in 82% of the patients. Time to biochemical control (median, IQR) was longer in CD (11.0 weeks, 5.6-29.8; p< 0.05) than in ACS (7.7 weeks, 4.1-17.1) and ECS (5.6 weeks, 4.1-23.3). Disease persistence or recurrence after first-line therapy was observed more often in CD (24% and 18%; p< 0.05) than in ECS (15% and 15%) and ACS (6% and 4%). Total time in hypercortisolism since diagnosis was significantly shorter in patients with CD diagnosed since 2013, after specialized patient care was implemented, compared to patients diagnosed before 2013 (13.5 weeks, vs. 26.1 weeks; p< 0.0070). Control of hypercortisolism at last follow up (76 months, 38-163) was achieved in 94% of patients with ACS, 100% of patients with ECS and 92% of patients with CD. CONCLUSIONS: Biochemical control can be achieved in most patients with different subtypes of CS within a reasonable time frame. Control of hypercortisolism has improved over time.

Prevalence and outcome of secondary hypogonadism in male patients with Cushing's syndrome and mild autonomous cortisol secretion.

BACKGROUND: Secondary hypogonadism (SH) is common in men with Cushing's syndrome (CS), but its impact on comorbidities is largely unknown and longitudinal data are scarce. If SH also affects men with mild autonomous cortisol secretion (MACS) is unknown. METHODS: We included 30 treatment-naïve adult men with CS and 17 men with MACS diagnosed since 2012. Hypogonadism was diagnosed based on total testosterone (TT) concentrations < 10.4 nmol/L and age-specific cut-offs. Outcomes were compared to age- and BMI-matched controls. In 20 men in remission of CS, a longitudinal analysis was conducted at 6, 12, and 24 months. RESULTS: Men with CS had significantly lower concentrations of TT, bioavailable T, and free T compared to controls (P < .0001) with lowest concentrations in ectopic CS. Likewise, TT was lower in men with MACS compared to controls. At baseline, 93% of men with CS and 59% of men with MACS had SH. Testosterone correlated negatively with late night salivary cortisol and serum cortisol pre- and post-1 mg dexamethasone suppression test. Following successful surgery, TT increased significantly (P = .001), normalising within 6 months. Despite normalisation, several RBC parameters remained lower in men with CS even 2 years after successful surgery. CONCLUSIONS: Secondary hypogonadism is common in men with CS and MACS but usually reversible after successful surgery. The persisting changes observed in RBC parameters need to be further investigated in larger cohorts and longer follow-up durations.

Delineating endogenous Cushing's syndrome by GC-MS urinary steroid metabotyping.

BACKGROUND: Diagnosing Cushing's syndrome (CS) is highly complex. As the diagnostic potential of urinary steroid metabolome analysis by gas chromatography-mass spectrometry (GC-MS) in combination with systems biology has not yet been fully exploited, we studied a large cohort of patients with CS. METHODS: We quantified daily urinary excretion rates of 36 steroid hormone metabolites. Applying cluster analysis, we investigated a control group and 168 patients: 44 with Cushing's disease (CD) (70% female), 18 with unilateral cortisol-producing adrenal adenoma (83% female), 13 with primary bilateral macronodular adrenal hyperplasia (PBMAH) (77% female), and 93 ruled-out CS (73% female). FINDINGS: Cluster-Analysis delineated five urinary steroid metabotypes in CS. Metabotypes 1, 2 and 3 revealing average levels of cortisol and adrenal androgen metabolites included patients with exclusion of CS or and healthy controls. Metabotype 4 reflecting moderately elevated cortisol metabolites but decreased DHEA metabolites characterized the patients with unilateral adrenal CS and PBMAH. Metabotype 5 showing strong increases both in cortisol and DHEA metabolites, as well as overloaded enzymes of cortisol inactivation, was characteristic of CD patients. 11-oxygenated androgens were elevated in all patients with CS. The biomarkers THS, F, THF/THE, and (An + Et)/(11ß-OH-An + 11ß-OH-Et) correctly classified 97% of patients with CS and 95% of those without CS. An inverse relationship between 11-deoxygenated and 11-oxygenated androgens was typical for the ACTH independent (adrenal) forms of CS with an accuracy of 95%. INTERPRETATION: GC-MS based urinary steroid metabotyping allows excellent identification of patients with endogenous CS and differentiation of its subtypes. FUNDING: The study was funded by the Else Kröner-Fresenius-Stiftung and the Eva-Luise-und-Horst-Köhler-Stiftung.

Diagnostic challenges in cyclic Cushing's syndrome: a systematic review.

Cyclic Cushing's syndrome is a subentity of Cushing's syndrome in which phases of biochemical hypercortisolism (peaks) are followed by spontaneous periods of physiological or even hypocortisolaemic cortisol secretion (troughs). To identify common features of cyclic Cushing's syndrome, we systematically reviewed single case reports and case series in MEDLINE from database inception to Oct 10, 2022, and identified 707 articles, of which 149 articles were assessed for eligibility and 118 articles (covering 212 cases) were included in the analysis. Pituitary tumours accounted for 67% of cases of cyclic Cushing's syndrome (n=143), ectopic tumours for 17% (n=36), and adrenal tumours for 11% (n=23). Occult tumours accounted for 2% of cases (n=4), and 3% of cases were unclassified (n=6). We compared the clinical symptoms and comorbidities of patients with cyclic Cushing's syndrome with those of patients with non-cyclic Cushing's syndrome and observed no major difference. In adrenocorticotropic hormone (ACTH)-dependent cyclic Cushing's syndrome, bilateral inferior petrosal sinus sampling had a positive (ie, true pituitary) and negative (ie, true ectopic) predictive value of 100% when performed during periods of hypercortisolism, versus a positive predictive value of 73% and a negative predictive value of 86% when performed, irrespective of cortisolaemic status. Overall, 6% of patients (n=12) with cyclic Cushing's syndrome had unnecessary surgery due to misclassification. Remission rates were significantly lower and the time to remission significantly longer in patients with cyclic Cushing's syndrome compared with patients with non-cyclic Cushing's syndrome (p<0·001). Variations in biochemical test results due to unpredictable cycle duration and frequency might cause diagnostic challenges resulting in misdiagnoses and missed diagnoses.

Lack of sensitivity of diagnostic Cushing-scores in Germany: a multicenter validation.

OBJECTIVE: Endogenous Cushing's syndrome (CS) is a severe condition, often diagnosed at a late stage. To reduce mortality, early diagnosis plays an important role. Two screening tools for early identification of patients with CS have been developed in multicentric cohorts, but have not yet been validated in cohorts with different geographic backgrounds. DESIGN: We validated the Spanish score published by Leon-Justel et al. in 2016 and the Italian score by Parasiliti-Caprino et al. published in 2021 in our cohort. METHODS: In the multicentric German Cushing registry, patients with confirmed and expected but ruled out Cushing's syndrome are prospectively diagnosed and followed up. We validated both scores in a cohort of 458 subjects: 176 patients with confirmed CS and 282 patients with suspected, but finally excluded CS. RESULTS: Using the Spanish score, 17.5% of our patients with proven CS biochemical screening would not have been recommended. This concerned patients with pituitary CS (22%) and with adrenal CS (10%). On the contrary, only 14% of patients without CS would have received a recommendation for biochemical screening. Using the Italian score, 29% of patients with proven CS were classified into the low-risk classes not recommended for biochemical screening. This mostly affected patients with adrenal (31%) and pituitary CS (30%). About 12% of subjects without CS would have received a biochemical screening recommendation. CONCLUSIONS: Both scores had limited sensitivity and high specificity in a German validation cohort. Further research is necessary to develop a screening score, which is effective in different healthcare systems and ethnicities.

Low-grade inflammation during the glucocorticoid withdrawal phase in patients with Cushing's syndrome.

IMPORTANCE: Endogenous Cushing's syndrome (CS) leads to profound immunosuppression. Successful surgery induces biochemical remission and reversal of immunosuppression, which is characterized by clinical signs of glucocorticoid withdrawal and associated with increased susceptibility to infections and thromboembolic complications. OBJECTIVE: We hypothesized that the glucocorticoid withdrawal phase is characterized by low-grade inflammation that may be related to patient-relevant outcomes. SETTING: In this retrospective observational study, we analyzed longitudinal data from 80 patients with CS prospectively enrolled in the German Cushing's registry between 2012 and 2021. All enrolled patients underwent successful surgery. In a second step, a case-control study was performed in 25 of the patients with age-, gender-, and body mass index-matched control patients in whom hypercortisolism was excluded. Analyses included the inflammatory markers C-reactive protein and interleukin-6, as well as body composition, muscle function testing, and quality-of-life questionnaires. The patients were studied during active CS and in the postoperative remission phase 1, 3, 6, 12, and 24 months after surgery. RESULTS: Compared with the preoperative phase and matched controls, patients with CS had increased systemic inflammatory markers in the early remission phase. One month following surgery, median (interquartile range) C-reactive protein was 0.48 mg dL-1 (0.14-0.90) vs 0.10 mg dL-1 (0.06-0.39) during active CS (P ≤ .001). Similarly, interleukin-6 1 month after surgery was 7.2 pg mL-1 (3.3-11.7) vs 1.7 pg mL-1 (1.5-2.5) during active CS (P ≤ .001). Obesity and hemoglobin A1c (HbA1c) were associated with increased inflammation levels. This proinflammatory state lasted until 1 year following surgery. Moreover, inflammatory markers during early remission showed an inverse correlation with long-term muscle function. CONCLUSIONS: The glucocorticoid withdrawal phase is associated with a low-grade inflammatory state, which is particularly pronounced in obese and hyperglycemic patients and related to lower muscle function.

Glucocorticoid receptor polymorphism BclI with increased glucocorticoid sensitivity has a positive influence on quality of life in endogenous Cushing's syndrome in remission.

CONTEXT: Patients with endogenous Cushing's syndrome (CS) may suffer from a wide range of neuropsychiatric symptoms leading to impaired quality of life (QoL). OBJECTIVE: Glucocorticoid receptor (GR) polymorphisms are associated with increased (BclI and N363S) or decreased (A3669G and ER22/23EK) GR sensitivity. HYPOTHESIS: GR genotypes may modulate and affect QoL and recovery after remission differently via GR sensitivity. METHODS: 295 patients with endogenous CS (81 active, 214 in remission) from 3 centers of the German Cushing's Registry were included for the cross-sectional analysis. All subjects were assessed with three questionnaires (CushingQoL, Tuebingen CD-25, SF-36). For the longitudinal part, 120 patients of them were analyzed at baseline and after 1.5 ± 0.9 yrs of follow-up. DNA samples were obtained from peripheral blood leukocytes for GR genotyping. RESULTS: Patients in remission scored significantly better than patients with active CS in the CushingQoL questionnaire and in the SF-36 sub-categories physical and social functioning, role-physical, bodily pain, and vitality. In cross-sectional analysis, no differences in QoL between minor allele and wildtype carriers were detected for all polymorphisms in active or cured CS. In longitudinal analysis, however, carriers with BclI minor allele showed significant improvement in SF-36 sub-categories vitality (P = .038) and mental health (P = .013) compared to wildtype carriers (active CS at baseline vs. CS in remission at follow-up). The outcome of the two questionnaires CushingQoL and Tuebingen CD-25 improved significantly in both wildtype and minor allele carriers. CONCLUSION: BclI minor allele carriers initially had the lowest QoL but recovered better from impaired QoL than wildtype carriers.

Diurnal Salivary Cortisol Profiles in Patients with Cushing's Syndrome.

BACKGROUND: Quantification of salivary cortisol is one of the highly sensitive and specific screening parameters for Cushing's syndrome (CS). However, only late-night salivary cortisol is part of the standard screening procedure. In this study, we aimed to analyze salivary cortisol day profiles in patients with different types of CS to test whether specific patterns might be relevant for diagnosis and subtyping. MATERIAL AND METHODS: Among 428 patients including those with confirmed Cushing's syndrome (N=111, of those 75 with Cushing's disease, 27 patients with adrenal CS and nine patients with ectopic CS), autonomous cortisol secretion (N=39) or exclusion of CS (control group, N=278) salivary cortisol was measured five times a day. RESULTS: At each of the five time points, salivary cortisol was significantly higher in patients with CS compared to the control group (p≤0.001). Using the entire profile instead of one single salivary cortisol at 11 p.m. improved diagnostic accuracy (85 vs. 91%) slightly. Patients with ACTH-dependent CS had higher salivary cortisol levels than patients with adrenal CS. Also, morning cortisol was significantly higher in patients with ectopic CS than in patients with Cushing's disease (p=0.04). Nevertheless, there was a strong overlap between diurnal profiles, and the diagnostic yield for subtyping was low. DISCUSSION: The study results show that using diurnal salivary cortisol profiles for CS diagnosis results in a limited increase in diagnostic accuracy. With significant differences between Cushing subtypes, cortisol profiles are not useful in everyday clinical practice for subtyping of CS.

Whom Should We Screen for Cushing Syndrome? The Endocrine Society Practice Guideline Recommendations 2008 Revisited.

CONTEXT: Cushing syndrome (CS) is a rare and serious disease with high mortality. Patients are often diagnosed late in the course of the disease. OBJECTIVE: This work investigated whether defined patient populations should be screened outside the at-risk populations defined in current guidelines. METHODS: As part of the prospective German Cushing registry, we studied 377 patients with suspected CS. The chief complaint for CS referral was documented. Using urinary free cortisol, late-night salivary cortisol, and the 1-mg dexamethasone suppression test as well as long-term clinical observation, CS was confirmed in 93 patients and ruled out for the remaining 284. RESULTS: Patients were referred for 18 key symptoms, of which 5 were more common in patients with CS than in those in whom CS was ruled out: osteoporosis (8% vs 2%; P = .02), adrenal incidentaloma (17% vs 8%, P = 0.01), metabolic syndrome (11% vs 4%; P = .02), myopathy (10% vs 2%; P < .001), and presence of multiple symptoms (16% vs 1%; P < .001). Obesity was more common in patients in whom CS was ruled out (30% vs 4%, P < .001), but recent weight gain was prominent in those with CS. A total of 68 of 93 patients with CS (73%) had typical chief complaints, as did 106 of 284 of patients with ruled-out CS status (37%) according to the Endocrine Society practice guideline 2008. CONCLUSION: The 2008 Endocrine Society Practice guideline for screening and diagnosis of CS defined at-risk populations that should undergo testing. These recommendations are still valid in 2022.

Steroid profiling using liquid chromatography mass spectrometry during adrenal vein sampling in patients with primary bilateral macronodular adrenocortical hyperplasia.

Introduction: Adrenal vein sampling (AVS) is not a routine procedure in patients with primary bilateral macronodular adrenocortical hyperplasia (PBMAH), but has been used to determine lateralization of cortisol secretion in order to guide decision of unilateral adrenalectomy. Our aim was to characterize the steroid fingerprints in AVS samples of patients with PBMAH and hypercortisolism and to identify a reference hormone for AVS interpretation. Method: Retrospectively, we included 17 patients with PBMAH from the German Cushing's registry who underwent AVS. 15 steroids were quantified in AVS and peripheral blood samples using LC-MS/MS. We calculated lateralization indices and conversion ratios indicative of steroidogenic enzyme activity to elucidate differences between individual adrenal steroidomes and in steroidogenic pathways. Results: Adrenal volume was negatively correlated with peripheral cortisone (r=0.62, p<0.05). 24-hour urinary free cortisol correlated positively with peripheral androgens (rDHEA=0.57, rDHEAS=0.82, rA=0.73, rT=0.54, p<0.05). DHEA was found to be a powerful reference hormone with high selectivity index, which did not correlate with serume cortisol and has a short half-life. All investigated steroids showed lateralization in single patients indicating the heterogenous steroid secretion pattern in patients with PBMAH. The ratios of corticosterone/aldosterone (catalyzed by CYP11B2), androstenedione/dehydroepiandrosterone (catalyzed by HSD3B2) and cortisone/cortisol (catalyzed by HSD11B2) in adrenal vein samples were higher in smaller adrenals (p<0.05). ARMC5 mutation carriers (n=6) showed lower androstenedione/17-hydroxyprogesterone and higher testosterone/androstenedione (p<0.05) ratios in peripheral blood, in line with lower peripheral androstenedione concentrations (p<0.05). Conclusion: Steroid profiling by LC-MS/MS led us to select DHEA as a candidate reference hormone for cortisol secretion. Lateralization and different steroid ratios showed that each steroid and all three steroidogenic pathways may be affected in PBMAH patients. In patients with germline ARMC5 mutations, the androgen pathway was particularly dysregulated.

The role of adrenal venous sampling (AVS) in primary bilateral macronodular adrenocortical hyperplasia (PBMAH): a study of 16 patients.

OBJECTIVE: Primary bilateral macronodular adrenocortical hyperplasia (PBMAH) is a rare cause of ACTH-independent Cushing's syndrome. Current guidelines recommend bilateral adrenalectomy for PBMAH, but several studies showed clinical effectiveness of unilateral adrenalectomy despite bilateral disease in selected patients. Our aim was to evaluate the gain of information which can be obtained through adrenal venous sampling (AVS) based cortisol lateralization ratios for guidance of unilateral adrenalectomy. DESIGN: We performed a retrospective analysis of 16 patients with PBMAH and clinical overt cortisol secretion in three centers METHODS: Selectivity of adrenal vein sampling during AVS was defined as a gradient of cortisol or a reference adrenal hormone ≥2.0 between adrenal and peripheral vein. Lateralization was assumed if the dominant to non-dominant ratio of cortisol to reference hormone was ≥4.0. RESULTS: AVS was technically successful in all patients based on absolute cortisol levels and in 13 of 16 patients (81%) based on reference hormone levels. Lateralization was documented in 8 of 16 patients. In patients with lateralization, in 5 of 8 cases this occurred toward morphologically larger adrenals, while in 3 patients lateralization was present in bilaterally identical adrenals. The combined volume of adrenals correlated positively with urinary free cortisol, suggesting that adrenal size is the dominant determinant of cortisol secretion. CONCLUSIONS: In this study the gain of information through AVS for unilateral adrenalectomy was limited in patients with PBMAH and marked adrenal asymmetry.

Chemosensory dysfunction in Cushing's syndrome.

PURPOSE: Cushing's syndrome (CS) can lead to structural changes in the brain and cognitive impairment, but chemosensory function has not been investigated yet. The aim was to analyze sense of smell and taste in patients with CS and explore the effect of therapy. METHODS: The study cohort comprised 20 patients with florid CS treated between 2018 and 2020 in the outpatient clinic of the LMU Munich. We compared these 20 patients with CS to 40 healthy subjects matched for age, sex, and smoking status. Patients' sense of smell and taste was examined at diagnosis and 3 months after successful therapeutic surgery leading to clinical and biochemical remission. Odor threshold, discrimination, and identification were measured with "Sniffin' Sticks", taste was measured with "Taste Strips". Perceived sense of smell and taste was retrieved via a questionnaire. RESULTS: Patients with florid CS had significantly reduced smell (total smell score 30.3 vs. 34.4, p < 0.0005) and taste scores (9.5 vs. 12.0, p < 0.0005) compared to controls and significantly more frequently hyposmia (55 vs. 2.5%, p < 0.0005), hypogeusia (40 vs. 0%, p < 0.0005), and self-reported chemosensory impairment (60 vs. 0%, p < 0.0005). Three months after successful surgery, CS patients showed significant improvement of odor threshold (8.1 vs. 7.0, p < 0.0005), odor discrimination (12.0 vs. 11.0, p = 0.003), total smell score (33.4 vs. 30.3, p < 0.0005), and taste (11.5 vs. 9.5, p = 0.003). CONCLUSIONS: Chemosensory dysfunction is a novel and clinically relevant feature of CS.

Metformin and Bone Metabolism in Endogenous Glucocorticoid Excess: An Exploratory Study.

Context: Glucocorticoid excess exhibits multiple detrimental effects by its catabolic properties. Metformin was recently suggested to protect from adverse metabolic side-effects of glucocorticoid treatment. Whether metformin is beneficial in patients with endogenous glucocorticoid excess has not been clarified. Objective: To evaluate the phenotype in patients with endogenous Cushing's syndrome (CS) treated with metformin at the time of diagnosis. Patients and Methods: As part of the German Cushing's Registry we selected from our prospective cohort of 96 patients all 10 patients who had been on pre-existing metformin treatment at time of diagnosis (CS-MET). These 10 patients were matched for age, sex and BMI with 16 patients without metformin treatment (CS-NOMET). All patients had florid CS at time of diagnosis. We analyzed body composition, metabolic parameters, bone mineral density and bone remodeling markers, muscle function and quality of life. Results: As expected, diabetes was more prevalent in the CS-MET group, and HbA1c was higher. In terms of comorbidities and the degree of hypercortisolism, the two groups were comparable. We did not observe differences in terms of muscle function or body composition. In contrast, bone mineral density in metformin-treated patients was superior to the CS-NOMET group at time of diagnosis (median T-Score -0.8 versus -1.4, p = 0.030). CS-MET patients showed decreased ß-CTX levels at baseline (p = 0.041), suggesting reduced bone resorption under metformin treatment during glucocorticoid excess. Conclusion: This retrospective cohort study supports potential protective effects of metformin in patients with endogenous glucocorticoid excess, in particular on bone metabolism.

Patients with low IGF-I after curative surgery for Cushing's syndrome have an adverse long-term outcome of hypercortisolism-induced myopathy.

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.

Corticotroph tumor progression after bilateral adrenalectomy (Nelson's syndrome): systematic review and expert consensus recommendations.

BACKGROUND: Corticotroph tumor progression (CTP) leading to Nelson's syndrome (NS) is a severe and difficult-to-treat complication subsequent to bilateral adrenalectomy (BADX) for Cushing's disease. Its characteristics are not well described, and consensus recommendations for diagnosis and treatment are missing. METHODS: A systematic literature search was performed focusing on clinical studies and case series (≥5 patients). Definition, cumulative incidence, treatment and long-term outcomes of CTP/NS after BADX were analyzed using descriptive statistics. The results were presented and discussed at an interdisciplinary consensus workshop attended by international pituitary experts in Munich on October 28, 2018. RESULTS: Data covered definition and cumulative incidence (34 studies, 1275 patients), surgical outcome (12 studies, 187 patients), outcome of radiation therapy (21 studies, 273 patients), and medical therapy (15 studies, 72 patients). CONCLUSIONS: We endorse the definition of CTP-BADX/NS as radiological progression or new detection of a pituitary tumor on thin-section MRI. We recommend surveillance by MRI after 3 months and every 12 months for the first 3 years after BADX. Subsequently, we suggest clinical evaluation every 12 months and MRI at increasing intervals every 2-4 years (depending on ACTH and clinical parameters). We recommend pituitary surgery as first-line therapy in patients with CTP-BADX/NS. Surgery should be performed before extrasellar expansion of the tumor to obtain complete and long-term remission. Conventional radiotherapy or stereotactic radiosurgery should be utilized as second-line treatment for remnant tumor tissue showing extrasellar extension.

Recurrence after pituitary surgery in adult Cushing's disease: a systematic review on diagnosis and treatment.

PURPOSE: Recurrence after pituitary surgery in Cushing's disease (CD) is a common problem ranging from 5% (minimum) to 50% (maximum) after initially successful surgery, respectively. In this review, we give an overview of the current literature regarding prevalence, diagnosis, and therapeutic options of recurrent CD. METHODS: We systematically screened the literature regarding recurrent and persistent Cushing's disease using the MESH term Cushing's disease and recurrence. Of 717 results in PubMed, all manuscripts in English and German published between 1980 and April 2020 were screened. Case reports, comments, publications focusing on pediatric CD or CD in veterinary disciplines or studies with very small sample size (patient number < 10) were excluded. Also, papers on CD in pregnancy were not included in this review. RESULTS AND CONCLUSIONS: Because of the high incidence of recurrence in CD, annual clinical and biochemical follow-up is paramount. 50% of recurrences occur during the first 50 months after first surgery. In case of recurrence, treatment options include second surgery, pituitary radiation, targeted medical therapy to control hypercortisolism, and bilateral adrenalectomy. Success rates of all these treatment options vary between 25 (some of the medical therapy) and 100% (bilateral adrenalectomy). All treatment options have specific advantages, limitations, and side effects. Therefore, treatment decisions have to be individualized according to the specific needs of the patient.

Glucocorticoid Receptor Polymorphisms Influence Muscle Strength in Cushing's Syndrome.

CONTEXT: An important clinical feature of Cushing's syndrome (CS) is proximal muscle myopathy caused by glucocorticoid induced protein metabolism. However, interindividual differences cannot be explained solely by the pure extent of hypercortisolemia. OBJECTIVE: To evaluate the effects of glucocorticoid receptor (GR) polymorphisms (BclI, N363S, ER22/23EK and A3669G), which influence peripheral glucocorticoid sensitivity on muscular function in endogenous CS. METHODS: 205 patients with proven endogenous CS (128 central, 77 adrenal) from 3 centers of the German Cushing's Registry and 125 subjects, in whom CS was ruled out, were included. All subjects were assessed for grip strength (via hand grip dynamometer) and performed a chair-rising test (CRT). DNA samples were obtained from peripheral blood leukocytes for GR genotyping. RESULTS: In patients with active CS, normalized handgrip strength of the dominant and nondominant hand was higher in A3669G minor allele than in wildtype carriers (P = .006 and P = .021, respectively). CS patients in remission and ruled-out CS showed no differences in handgrip strength regarding A3669G minor allele and wildtype carriers. Male CS patients harboring the ER22/23EK wildtype presented lower hand grip strength than minor allele carriers (P = .049 dominant hand; P = .027 nondominant hand). The other polymorphisms did not influence handgrip strength. CRT showed no differences regarding GR polymorphisms carrier status. CONCLUSION: Handgrip strength seems to be more susceptible to hypercortisolism in A3669G wildtype than in A3669G minor allele carriers. This might partially explain the inter-individual differences of glucocorticoid-induced myopathy in patients with endogenous CS. ER22/23EK polymorphism seems to exert sex-specific differences.

Persisting Muscle Dysfunction in Cushing's Syndrome Despite Biochemical Remission.

CONTEXT: Glucocorticoid-induced myopathy is a characteristic symptom of endogenous Cushing's syndrome (CS). Its long-term outcome is largely unknown. OBJECTIVE: To evaluate long-term muscle function following the remission of endogenous CS. STUDY DESIGN: Observational longitudinal cohort study. SETTING: Tertiary care hospitals and a specialized outpatient clinic. PATIENTS: As part of the prospective multicenter German Cushing's Registry, we assessed muscle strength in patients with overt endogenous CS. We studied the patients at the time of diagnosis (n = 88), after 6 months (n = 69), and thereafter annually, following surgical remission over a period of up to 4 years (1 year: n = 55; 2 years: n = 34; 3 years: n = 29; 4 years: n = 22). Muscle function was evaluated by hand grip strength and by chair rising test. RESULTS: Grip strength was decreased to 83% of normal controls (100%) at the time of diagnosis. It further decreased to 71% after 6 months in remission (P ≤ 0.001) and showed no improvement during further follow-up compared with baseline. Chair rising test performance improved initially (8 seconds at baseline vs 7 seconds after 6 months, P = 0.004) but remained at this reduced level thereafter (7 seconds after 3 years vs 5 seconds in controls, P = 0.038). In multivariate analysis, we identified, as predictors for long-term muscle dysfunction, age, waist-to-hip ratio, and hemoglobin A1c at baseline. Furthermore, muscle strength during follow-up was strongly correlated with quality of life. CONCLUSION: This study shows that CS-associated myopathy does not spontaneously resolve during remission. This calls for action to identify effective interventions to improve muscle dysfunction in this setting.