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Dive into the research topics where Christina Dimopoulou is active.

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Featured researches published by Christina Dimopoulou.


The Journal of Clinical Endocrinology and Metabolism | 2015

The Gene of the Ubiquitin-Specific Protease 8 Is Frequently Mutated in Adenomas Causing Cushing's Disease

Luis Gustavo Perez-Rivas; Marily Theodoropoulou; Francesco Ferraù; Clara Nusser; Kohei Kawaguchi; Constantine A. Stratakis; Fabio R. Faucz; Luiz Eduardo Wildemberg; Guillaume Assié; Rudi Beschorner; Christina Dimopoulou; Michael Buchfelder; Vera Popovic; Christina Maria Berr; Miklós Tóth; Arif Ibrahim Ardisasmita; Jürgen Honegger; Jérôme Bertherat; Mônica R. Gadelha; Felix Beuschlein; Günter K. Stalla; Masayuki Komada; Márta Korbonits; Martin Reincke

CONTEXT We have recently reported somatic mutations in the ubiquitin-specific protease USP8 gene in a small series of adenomas of patients with Cushings disease. OBJECTIVE To determine the prevalence of USP8 mutations and the genotype-phenotype correlation in a large series of patients diagnosed with Cushings disease. DESIGN We performed a retrospective, multicentric, genetic analysis of 134 functioning and 11 silent corticotroph adenomas using Sanger sequencing. Biochemical and clinical features were collected and examined within the context of the mutational status of USP8, and new mutations were characterized by functional studies. PATIENTS A total of 145 patients who underwent surgery for an ACTH-producing pituitary adenoma. MAIN OUTCOMES MEASURES Mutational status of USP8. Biochemical and clinical features included sex, age at diagnosis, tumor size, preoperative and postoperative hormonal levels, and comorbidities. RESULTS We found somatic mutations in USP8 in 48 (36%) pituitary adenomas from patients with Cushings disease but in none of 11 silent corticotropinomas. The prevalence was higher in adults than in pediatric cases (41 vs 17%) and in females than in males (43 vs 17%). Adults having USP8-mutated adenomas were diagnosed at an earlier age than those with wild-type lesions (36 vs 44 y). Mutations were primarily found in adenomas of 10 ± 7 mm and were inversely associated with the development of postoperative adrenal insufficiency. All the mutations affected the residues Ser718 or Pro720, including five new identified alterations. Mutations reduced the interaction between USP8 and 14-3-3 and enhanced USP8 activity. USP8 mutants diminished epidermal growth factor receptor ubiquitination and induced Pomc promoter activity in immortalized AtT-20 corticotropinoma cells. CONCLUSIONS USP8 is frequently mutated in adenomas causing Cushings disease, especially in those from female adult patients diagnosed at a younger age.


European Journal of Endocrinology | 2014

Long-term remission and recurrence rates after first and second transsphenoidal surgery for Cushing's disease: care reality in the Munich Metropolitan Region

Christina Dimopoulou; Jochen Schopohl; Walter Rachinger; M Buchfelder; J Honegger; Martin Reincke; G. K. Stalla

OBJECTIVE Transsphenoidal surgery (TSS) presents the treatment of choice for Cushings disease (CD). Remission and recurrence rates vary dependent on tumor size, extension, adenoma visibility on magnetic resonance imaging, and neurosurgical expertise. Other than published from single-surgeon neurosurgical series so far, we have aimed to describe long-term remission and recurrence rates of CD in a series incorporating different neurosurgeons, trying to reflect care reality in the Munich Metropolitan Region, which is accommodated by three tertiary university and multiple, smaller neurosurgical centers. DESIGN We conducted a retrospective analysis of 120 patients who underwent first and 36 patients who underwent second TSS as treatment for CD between 1990 and 2012. METHODS Patients were divided into three groups according to remission status. Potential risk factors for recurrence, pituitary function, and strategy in persistent disease were assessed. RESULTS THREE OUTCOME GROUPS WERE IDENTIFIED ACCORDING TO REMISSION STATUS AFTER FIRST TSS (MEAN FOLLOW-UP 79 MONTHS): remission, 71% (85/120), disease persistence, 29% (35/120), and disease recurrence, 34% (29/85) (mean time to recurrence 54 months). After second TSS (n=36, mean follow-up 62 months), we documented remission in 42% (15/36), disease persistence in 58% (21/36), and disease recurrence in 40% (6/15) (mean time to recurrence 42 months). Postoperative hypocortisolism after first, though not after second, TSS was associated with a lower risk of suffering disease recurrence (risk=0.72; 95% CI 0.60-0.88; exact significance (two-sided) P=0.035). CONCLUSIONS Our study shows higher recurrence rates of CD after first TSS than previously reported. Second TSS leads an additional 8% of the patients to long-term CD remission.


Clinical Endocrinology | 2009

Prevalence of mental disorders in acromegaly: a cross‐sectional study in 81 acromegalic patients

Caroline Sievers; Christina Dimopoulou; Hildegard Pfister; Roselind Lieb; B. Steffin; J. Roemmler; Jochen Schopohl; Marion Mueller; Harald Schneider; Marcus Ising; Hans-Ulrich Wittchen; Guenter Karl Stalla

Objective  Emotional and behavioural alterations have been described in acromegalic patients. However, the nature and psychopathological value of these changes remained unclear.


Pituitary | 2012

Cognitive function in acromegaly: description and brain volumetric correlates.

Caroline Sievers; Philipp G. Sämann; Hildegard Pfister; Christina Dimopoulou; Michael Czisch; J. Roemmler; J. Schopohl; G. K. Stalla; J. Zihl

In acromegaly, we reported on increased rates of affective disorders such as dysthymia and depression, as well as structural brain changes. Objective of this study was to determine if cognitive impairments in patients with acromegaly exist and whether such impairments are associated with structural brain alterations defined by magnetic resonance imaging (MRI). In this cross-sectional study, 55 patients with biochemically confirmed acromegaly were enrolled. MRI data were compared with 87 control subjects. Main outcome measures were performance levels in 13 cognitive tests covering the domains of attention, memory and executive function, with performance below the cut-off level of the 16th percentile rated as impaired. In addition, individual global and hippocampal volume changes were defined for each patient in reference to a normative sample. We found that up to 33.3% of the patients were impaired in the attention, up to 24.1% in the memory, and up to 16.7% in the executive function domain. 67.3% of the patients failed to reach the cut-off level in at least one subtest. MRI demonstrated increased global, left and right hippocampal grey matter and white matter, particularly early in the disease course. Rather few positive than expected negative correlations could be established between the hippocampal grey matter gain and cognitive performance. Cognitive dysfunction, particularly attentional deficits, are common in acromegaly, rendering neuropsychological testing essential in the diagnostic work-up.


The Journal of Clinical Endocrinology and Metabolism | 2015

The Incidence of Cancer Among Acromegaly Patients: Results From the German Acromegaly Registry

David Petroff; Anke Tönjes; Martin Grussendorf; Michael Droste; Christina Dimopoulou; Günter K. Stalla; Cornelia Jaursch-Hancke; Manuel Mai; Jochen Schopohl; Christof Schöfl

CONTEXT Acromegaly is a rare disease characterized by high serum levels of GH and IGF-1. Animal studies have demonstrated links between these hormones and cancer, but data regarding cancer incidence among acromegaly patients are inconsistent. Moreover, therapy options have changed considerably since many of the aforementioned data were collected. OBJECTIVE The objective was to determine whether the overall and site-specific incidence of cancer is comparable to that of the general population. DESIGN AND SETTING Data from the German Acromegaly Registry for 446 patients (6656 person-years from diagnosis) treated in seven specialized endocrine centers were analyzed. MAIN OUTCOME MEASURE Standard incidence ratios (SIRs) were calculated as compared to the general population. RESULTS Overall cancer incidence was slightly but not significantly lower than in the general population (SIR, 0.75; 95% confidence interval, 0.55 to 1.00; P = .051) and was not significantly higher for colorectal, breast, thyroid, prostate, and lung cancers. The SIRs of those with GH in the ranges <1, 1-2.5, and ≥ 2.5 ng/mL were 0.75, 0.44, and 0.92, respectively (P = .94). There was not a significant dependence on normal vs elevated IGF-1 (P = .87), radiation therapy (P = .45), disease duration (P = .96), age at diagnosis (P = .15), or during a period of high GH and IGF-1 from 8 years before to 2 years after diagnosis of acromegaly (P = .41). CONCLUSIONS Cancer screening strategies need to take incidence into account, which does not seem to be substantially higher in treated acromegaly patients than in the general population for any site of cancer.


Frontiers in Endocrinology | 2015

Health outcomes in acromegaly: depression and anxiety are promising targets for improving reduced quality of life

Victor Geraedts; Christina Dimopoulou; Matthias K. Auer; Jochen Schopohl; Günter Karl Stalla; Caroline Sievers

Introduction: Remission criteria of acromegaly are based on biochemical variables, i.e., normalization of increased hormone levels. However, the established reduction in Quality of Life (QoL) is suggested to be independent of biochemical control. The aim of this study was to test which aspects predict QoL best in acromegaly. Methods/design: This is a prospective cohort study in 80 acromegalic patients, with a cross-sectional and longitudinal part. The main outcome measure was health-related QoL, measured by a generic and a disease-specific questionnaire (the SF-36 and AcroQoL). Main predictors were age, gender, biochemical control, disease characteristics, treatment modalities, and psychopathology. Results: Our cohort of 80 acromegalics had a mean age 54.7 ± 12.3 years with an average disease duration of 10.8 ± 10.0 years. Ratio macro-/microadenoma was 54/26. In adjusted mixed method models, we found that psychopathology significantly predicts QoL in acromegaly (in models including the variables age, gender, disease duration, tumor size, basal hormone levels, relevant treatment modalities, and relevant comorbidities), with a higher degree of psychopathology indicating a lower QoL (depression vs. AcroQoL: B = −1.175, p < 0.001, depression vs. SF-36: B = −1.648, p < 0.001, anxiety vs. AcroQoL: B = −0.399, p < 0.001, anxiety vs. SF-36: B = −0.661, p < 0.001). The explained variances demonstrate superiority of psychopathology over biochemical control and other variables in predicting QoL in our models. Discussion: Superiority of psychopathology over biochemical control calls for a more extensive approach regarding diagnosing depression and anxiety in pituitary adenomas to improve QoL. Depressive symptoms and anxiety are modifiable factors that might provide valuable targets for possible future treatment interventions.


The Journal of Clinical Endocrinology and Metabolism | 2014

Frequency of AIP gene mutations in young patients with acromegaly: a registry-based study

Christof Schöfl; Jürgen Honegger; Michael Droste; Martin Grussendorf; Reinhard Finke; Ursula Plöckinger; Christian Berg; Holger S. Willenberg; Alexander Lammert; Dietrich Klingmüller; Cornelia Jaursch-Hancke; Anke Tönjes; Sabine Schneidewind; Jörg Flitsch; Catharina Bullmann; Christina Dimopoulou; Günter K. Stalla; Bernhard Mayr; Wolfgang Hoeppner; Jochen Schopohl

CONTEXT Familial and sporadic GH-secreting pituitary adenomas are associated with mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene. Patients with an AIP mutation (AIPmut) tend to have more aggressive tumors occurring at a younger age. OBJECTIVE The objective of the study was to investigate the frequency of AIPmut in patients diagnosed at 30 years of age or younger. DESIGN The German Acromegaly Registry database (1795 patients in 58 centers) was screened for patients diagnosed with acromegaly at 30 years of age or younger (329 patients). Sixteen centers participated and 91 patients consented to AIPmut analysis. INTERVENTION DNA was analyzed by direct sequencing and multiplex ligation dependent probe amplification Main outcome Measures: The number of patients with AIPmut was measured. RESULTS Five patients had either a mutation (c.490C>T, c.844C>T, and c.911G>A, three males) or gross deletions of exons 1 and 2 of the AIP gene (n = 2, one female). The overall frequency of an AIPmut was 5.5%, and 2.3% or 2.4% in patients with an apparently sporadic adenoma or macroadenoma, respectively. By contrast, three of four patients (75%) with a positive family history were tested positive for an AIPmut. Except for a positive family history, there were no significant differences between patients with and without an AIPmut. CONCLUSIONS The frequency of AIPmut in this registry-based cohort of young patients with acromegaly is lower than previously reported. Patients with a positive family history should be tested for an AIPmut, whereas young patients without an apparent family history should be screened, depending on the individual cost to benefit ratio.


European Journal of Endocrinology | 2014

Clinical characteristics of pain in patients with pituitary adenomas.

Christina Dimopoulou; Ap Athanasoulia; Erik Hanisch; Stefanie Held; Till Sprenger; Thomas R Toelle; Josefine Roemmler-Zehrer; Jochen Schopohl; Günter K. Stalla; Caroline Sievers

OBJECTIVE Clinical presentation of pituitary adenomas frequently involves pain, particularly headache, due to structural and functional properties of the tumour. Our aim was to investigate the clinical characteristics of pain in a large cohort of patients with pituitary disease. DESIGN In a cross-sectional study, we assessed 278 patients with pituitary disease (n=81 acromegaly; n=45 Cushings disease; n=92 prolactinoma; n=60 non-functioning pituitary adenoma). METHODS Pain was studied using validated questionnaires to screen for nociceptive vs neuropathic pain components (painDETECT), determine pain severity, quality, duration and location (German pain questionnaire) and to assess the impact of pain on disability (migraine disability assessment, MIDAS) and quality of life (QoL). RESULTS We recorded a high prevalence of bodily pain (n=180, 65%) and headache (n=178, 64%); adrenocorticotropic adenomas were most frequently associated with pain (n=34, 76%). Headache was equally frequent in patients with macro- and microadenomas (68 vs 60%; P=0.266). According to painDETECT, the majority of the patients had a nociceptive pain component (n=193, 80%). Despite high prevalence of headache, 72% reported little or no headache-related disability (MIDAS). Modifiable factors including tumour size, genetic predisposition, previous surgery, irradiation or medical therapy did not have significant impact neither on neuropathic pain components (painDETECT) nor on headache-related disability (MIDAS). Neuropathic pain and pain-related disability correlated significantly with depression and impaired QoL. CONCLUSIONS Pain appears to be a frequent problem in pituitary disease. The data suggest that pain should be integrated in the diagnostic and therapeutic work-up of patients with pituitary disease in order to treat them appropriately and improve their QoL.


European Journal of Endocrinology | 2014

Food intake regulating hormones in adult craniopharyngioma patients.

Josefine Roemmler-Zehrer; Veronika Geigenberger; Sylvère Störmann; Marco Losa; Valentina Crippa; B. Otto; Martin Bidlingmaier; Christina Dimopoulou; Günter K. Stalla; Jochen Schopohl

INTRODUCTION Patients with craniopharyngioma (CP) have disturbances of the hypothalamic-pituitary axis and serious comorbidities such as obesity. We hypothesized that the secretion of hormones regulating the nutritional status is altered in adult patients with CP compared with patients with non-functioning pituitary adenoma (NFPA). METHODS WE INCLUDED 40 CP (50% MALES, MEAN AGE: 49.6±14.3 years) and 40 NFPA (72.5% males, mean age: 63.4±9.8 years) patients. We measured glucose, insulin, leptin, total ghrelin, peptide-YY (PYY) and cholecystokinin (CCK) during oral glucose tolerance test (OGTT). Fat mass (FM) was determined by dual X-ray absorptiometry. RESULTS Gender distribution was not significantly different, but CP patients were significantly younger (P<0.001). CP patients had significantly higher BMI and FM than NFPA patients (BMI 32±8 vs 28±4 kg/m(2), P=0.009 and FM 37±9 vs 33±9%, P=0.02). Fasting glucose level (84±12 vs 78±11 mg/dl, P=0.03), leptin (27.9±34.2 vs 11.9±11.6 μg/l, P=0.008) and leptin levels corrected for percentage FM (0.66±0.67 vs 0.32±0.25 μg/l%, P=0.005) were significantly higher in CP than in NFPA patients, whereas ghrelin was significantly lower (131±129 vs 191±119 ng/l, P=0.035). Insulin, PYY and CCK did not differ significantly between groups. After glucose load, leptin decreased significantly in CP patients (P=0.019). In both groups, ghrelin decreased significantly during OGTT (both P<0.001). The percentage decline was significantly smaller for CP. PYY and CCK increased equally after glucose in both groups. CONCLUSION Our patients with CP have more metabolic complications than our patients with NFPA. The levels of leptin and ghrelin at fasting status and after glucose seem to be altered in CP, whereas changes in insulin, PYY and CCK do not seem to be responsible for the metabolic changes in these patients.


European Journal of Endocrinology | 2017

Persistence of myopathy in Cushing's syndrome: evaluation of the German Cushing's Registry

Christina Maria Berr; Mareike R. Stieg; Timo Deutschbein; Marcus Quinkler; Ralf Schmidmaier; Andrea Osswald; Nicole Reisch; Katrin Ritzel; Christina Dimopoulou; Julia Fazel; Stefanie Hahner; Günter K. Stalla; Felix Beuschlein; Martin Reincke

BACKGROUND Cushings syndrome (CS) is characterized by an excessive secretion of glucocorticoids that results in a characteristic clinical phenotype. One feature of clinical hypercortisolism is breakdown of protein metabolism translating into clinical consequences including glucocorticoid-induced myopathy. While surgery is effective in control of cortisol excess, the effect of biochemical remission on muscular function is yet unclear. METHODS In a cross-sectional study we analyzed 47 patients with CS during the florid phase (ActiveCS). 149 additional patients were studied 2-53 years (mean: 13 years) after surgery in biochemical long-term remission (RemissionCS). Also, 93 rule-out CS patients were used as controls (CON). All subjects were assessed for grip strength using a hand grip dynamometer and underwent the chair rising test (CRT). RESULTS Hand grip strength (85% vs 97% of norm, P = 0.002) and the CRT performance (9.5 s vs 7.1 s, P = 0.001) were significantly lower in ActiveCS compared to the CON group. Six months after treatment grip strength further decreased in CS (P = 0.002) and CRT performance remained impaired. The RemissionCS group (mean follow-up 13 years) had reduced hand grip strength (92% compared to normal reference values for dominant hand, P < 0.001). The chair rising test performance was at 9.0 s and not significantly different from the ActiveCS group (P = 0.45). CONCLUSION CS affects muscle strength in the acute phase, but functional impairment remains detectable also during long-term follow-up despite biochemical remission.

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Harald Schneider

Helmholtz-Zentrum Dresden-Rossendorf

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Hans-Ulrich Wittchen

Dresden University of Technology

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