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Dive into the research topics where Ragnhildur Bergthorsdottir is active.

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Featured researches published by Ragnhildur Bergthorsdottir.


The Journal of Clinical Endocrinology and Metabolism | 2012

Improved Cortisol Exposure-Time Profile and Outcome in Patients with Adrenal Insufficiency: A Prospective Randomized Trial of a Novel Hydrocortisone Dual-Release Formulation

Gudmundur Johannsson; Ann-Sofie Nilsson; Ragnhildur Bergthorsdottir; Pia Burman; Per Dahlqvist; Bertil Ekman; Britt Edén Engström; Tommy Olsson; Oskar Ragnarsson; Mats Ryberg; Jeanette Wahlberg; Beverly M. K. Biller; John P. Monson; Paul M. Stewart; Hans Lennernäs; Stanko Skrtic

CONTEXT Patients with treated adrenal insufficiency (AI) have increased morbidity and mortality rate. Our goal was to improve outcome by developing a once-daily (OD) oral hydrocortisone dual-release tablet with a more physiological exposure-time cortisol profile. OBJECTIVE The aim was to compare pharmacokinetics and metabolic outcome between OD and the same daily dose of thrice-daily (TID) dose of conventional hydrocortisone tablets. DESIGN AND SETTING We conducted an open, randomized, two-period, 12-wk crossover multicenter trial with a 24-wk extension at five university hospital centers. PATIENTS The trial enrolled 64 adults with primary AI; 11 had concomitant diabetes mellitus (DM). INTERVENTION The same daily dose of hydrocortisone was administered as OD dual-release or TID. MAIN OUTCOME MEASURE We evaluated cortisol pharmacokinetics. RESULTS Compared with conventional TID, OD provided a sustained serum cortisol profile 0-4 h after the morning intake and reduced the late afternoon and the 24-h cortisol exposure. The mean weight (difference = -0.7 kg, P = 0.005), systolic blood pressure (difference = -5.5 mm Hg, P = 0.0001) and diastolic blood pressure (difference: -2.3 mm Hg; P = 0.03), and glycated hemoglobin (absolute difference = -0.1%, P = 0.0006) were all reduced after OD compared with TID at 12 wk. Compared with TID, a reduction in glycated hemoglobin by 0.6% was observed in patients with concomitant DM during OD (P = 0.004). CONCLUSION The OD dual-release tablet provided a more circadian-based serum cortisol profile. Reduced body weight, reduced blood pressure, and improved glucose metabolism were observed during OD treatment. In particular, glucose metabolism improved in patients with concomitant DM.


European Journal of Endocrinology | 2009

Improving glucocorticoid replacement therapy using a novel modified-release hydrocortisone tablet: a pharmacokinetic study

Gudmundur Johannsson; Ragnhildur Bergthorsdottir; Anna G Nilsson; Hans Lennernäs; Thomas Hedner; Stanko Skrtic

BACKGROUND Endogenous plasma cortisol levels have a well-defined circadian rhythm. The aim of this project is to develop a once daily oral dual-release formulation for cortisol replacement therapy that mimics the diurnal variation in the plasma cortisol profile. OBJECTIVE To determine single-dose plasma pharmacokinetics and dose-proportionality of oral 5 and 20 mg dual-release hydrocortisone tablets in healthy volunteers. In addition, the effect of food intake was investigated for the 20 mg dose. DESIGN A randomised, controlled, two-way cross-over, double-blind, phase I study of oral hydrocortisone (modified (dual) release; 5 and 20 mg) with an open food-interaction arm. METHODS The single dose pharmacokinetic studies were performed with betamethasone suppression. The two first study days were blinded and randomised between morning administration of 5 and 20 mg tablet in a fasting state. The third day was open with a 20 mg tablet taken 30 min after a high-calorie, high-fat meal. The plasma samples were assayed using both a validated LC-MS/MS and an immunoassay. The plasma pharmacokinetic variables were calculated using non-compartmental data analysis. RESULTS The time to reach a clinically significant plasma concentration of cortisol (>200 nmol/l) was within 20 min and a mean peak of 431 (s.d. 126) nmol/l was obtained within 50 min after administration of the 20 mg tablet. Plasma cortisol levels remained above 200 nmol/l for around 6 h thereafter and all plasma concentrations 18-24 h after intake were below 50 nmol/l. In the fed state the time to reach 200 nmol/l was delayed by 28 and 9 min based on LC-MS/MS and immunoassay, respectively. The 5 and 20 mg tablets produced an increase in plasma exposure of cortisol that was not fully dose proportional. CONCLUSION The dual release hydrocortisone tablet with once-daily administration produced a diurnal plasma cortisol profile mimicking the physiological serum cortisol profile.


European Journal of Endocrinology | 2014

Prospective evaluation of long-term safety of dual-release hydrocortisone replacement administered once daily in patients with adrenal insufficiency

Anna G. Nilsson; C Marelli; D Fitts; Ragnhildur Bergthorsdottir; Pia Burman; Per Dahlqvist; Bertil Ekman; B. Eden Engstrom; Tommy Olsson; Oskar Ragnarsson; Mats Ryberg; Jeanette Wahlberg; H Lennernäs; Stanko Skrtic; Gudmundur Johannsson

Objective The objective was to assess the long-term safety profile of dual-release hydrocortisone (DR-HC) in patients with adrenal insufficiency (AI). Design Randomised, open-label, crossover trial of DR-HC or thrice-daily hydrocortisone for 3 months each (stage 1) followed by two consecutive, prospective, open-label studies of DR-HC for 6 months (stage 2) and 18 months (stage 3) at five university clinics in Sweden. Methods Sixty-four adults with primary AI started stage 1, and an additional 16 entered stage 3. Patients received DR-HC 20–40 mg once daily and hydrocortisone 20–40 mg divided into three daily doses (stage 1 only). Main outcome measures were adverse events (AEs) and intercurrent illness (self-reported hydrocortisone use during illness). Results In stage 1, patients had a median 1.5 (range, 1–9) intercurrent illness events with DR-HC and 1.0 (1–8) with thrice-daily hydrocortisone. AEs during stage 1 were not related to the cortisol exposure-time profile. The percentage of patients with one or more AEs during stage 1 (73.4% with DR-HC; 65.6% with thrice-daily hydrocortisone) decreased during stage 2, when all patients received DR-HC (51% in the first 3 months; 54% in the second 3 months). In stages 1–3 combined, 19 patients experienced 27 serious AEs, equating to 18.6 serious AEs/100 patient-years of DR-HC exposure. Conclusions This long-term prospective trial is the first to document the safety of DR-HC in patients with primary AI and demonstrates that such treatment is well tolerated during 24 consecutive months of therapy.


Hormone Research in Paediatrics | 2007

Long-Acting Hydrocortisone for Glucocorticoid Replacement Therapy

Gudmundur Johannsson; Helena Filipsson; Ragnhildur Bergthorsdottir; Hans Lennernäs; Stanko Skrtic

Background: Glucocorticoid (GC) deficiency is a consequence of various disorders that are by themselves rare. Because of this low prevalence, the low cost of GC replacement therapy and the belief that existing outcomes are good, there has been little interest in development of new and improved pharmaceutical products for treatment of GC deficiency. However, GC replacement therapy is complex: diurnal variation of endogenous cortisol must be replicated, GC needs may change during times of physical and psychological stress and there is no biomarker of its action that can be used to monitor individual dose response. Current Limitations: Recent data suggest that the outcome of established long-term GC replacement therapy may not be as good as previously believed. Short-acting GCs such as hydrocortisone (HC) and cortisone acetate for replacement therapy require 2 to 3 administrations per day. Developing Alternatives: Drug delivery system technologies are now available that could permit design and manufacture of a formulation that could accommodate once-daily administration of HC. Such a formulation would enable more physiological serum cortisol-time profiles than are possible with currently available formulations. This short review provides some background on GC replacement therapy, along with recent data on the outcome of patient groups with GC insufficiency, and briefly discusses some general principles for a controlled-release (‘long-acting’) HC formulation.


The Journal of Clinical Endocrinology and Metabolism | 2014

Common Genetic Variants in the Glucocorticoid Receptor and the 11β-Hydroxysteroid Dehydrogenase Type 1 Genes Influence Long-Term Cognitive Impairments in Patients With Cushing's Syndrome in Remission

Oskar Ragnarsson; Camilla A. M. Glad; Peter Berglund; Ragnhildur Bergthorsdottir; Derek N. Eder; Gudmundur Johannsson

CONTEXT Cognitive function is impaired in patients with Cushings syndrome (CS) in remission. OBJECTIVE The objective of the investigation was to study the effects of polymorphisms in genes associated with glucocorticoid (GC) sensitivity on cognitive function in patients with CS in long-term remission. DESIGN This was a cross-sectional, case-controlled, single-center study. PATIENTS Fifty-three patients with CS in remission and 53 controls matched for age, gender, and educational level participated in the study. MAIN OUTCOME MEASURES Cognitive function, studied using standardized neuropsychological testing, and polymorphisms in the GC receptor (NR3C1; Bcl1 and A3669G), mineralocorticoid receptor (NR3C2; I180V), 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1; rs11119328), and ATP binding cassette B1 (ABCB1; rs1045642) genes were measured. The association between cognitive function and polymorphisms were analyzed using linear regression with adjustments for age and educational level. RESULTS The mean age in patients and controls was 53 ± 14 years. The median (interquartile range) duration of remission was 13 (5-18) years. In patients, the single-nucleotide polymorphism rs11119328 was associated with impairments in processing speed, auditory attention, auditory working memory, and reading speed. This association was not seen in matched controls. The Bcl1 polymorphism was associated with fatigue and worse visual attention and working memory. The remaining single-nucleotide polymorphisms were not associated with cognitive performance. CONCLUSION In this study, polymorphisms in the 11βHSD1 and NR3C1 genes were associated with impaired cognitive function, indicating that GC sensitivity and prereceptor regulation of GC action may play a role in the long-term consequences of CS. The study provides a novel insight into the etiology of cognitive dysfunction in patients with CS in remission.


The Journal of Clinical Endocrinology and Metabolism | 2016

Clinical and immunological characteristics of Autoimmune Addison's disease : a nationwide Swedish multicenter study

Frida Dalin; Gabriel Nordling Eriksson; Per Dahlqvist; Åsa Hallgren; Jeanette Wahlberg; Olov Ekwall; Stefan Söderberg; Johan Rönnelid; Per Olcén; Ola Winqvist; Sergiu-Bogdan Catrina; Berit Kriström; Maria Laudius; Magnus Isaksson; Maria Halldin Stenlid; Jan Gustafsson; Gennet Gebre-Medhin; Sigridur Bjornsdottir; Annika Janson; Anna Karin Akerman; Jan Åman; Karel Duchén; Ragnhildur Bergthorsdottir; Gudmundur Johannsson; Emma Lindskog; Mona Landin-Olsson; Maria Elfving; Erik Waldenstrom; Anna Lena Hulting; Olle Kämpe

Context: Studies of the clinical and immunological features of autoimmune Addison disease (AAD) are needed to understand the disease burden and increased mortality. Objective: To provide upgraded data on autoimmune comorbidities, replacement therapy, autoantibody profiles, and cardiovascular risk factors. Design, Setting, and Participants: A cross-sectional, population-based study that included 660 AAD patients from the Swedish Addison Registry (2008–2014). When analyzing the cardiovascular risk factors, 3594 individuals from the population-based survey in Northern Sweden, MONICA (monitoring of trends and determinants of cardiovascular disease), served as controls. Main Outcome Measures: The endpoints were the prevalence of autoimmune comorbidities and cardiovascular risk factors. Autoantibodies against 13 autoantigens were determined. Results: The proportion of 21-hydroxylase autoantibody-positive patients was 83%, and 62% of patients had ≥1 associated autoimmune diseases, more frequently coexisting in females (P < 0.0001). AAD patients had a lower body mass index (P < 0.0001) and prevalence of hypertension (P = 0.027) compared with controls. Conventional hydrocortisone tablets were used by 89% of the patients, with a mean dose of 28.1 ± 8.5 mg/d. The mean hydrocortisone equivalent dose normalized to the body surface was 14.8 ± 4.4 mg/m2/d. A greater hydrocortisone equivalent dose was associated with a greater incidence of hypertension (P = 0.046). Conclusions: Careful monitoring of AAD patients is warranted to detect associated autoimmune diseases. Contemporary Swedish AAD patients did not have an increased prevalence of overweight, hypertension, type 2 diabetes mellitus, or hyperlipidemia. However, high glucocorticoid replacement doses could be a risk factor for hypertension.


PLOS ONE | 2014

Cardiovascular risk factors in patients with Addison's disease: a comparative study of South African and Swedish patients.

Ragnhildur Bergthorsdottir; Naomi S. Levitt; Joel A. Dave; Desmond A. Schatz; David Marais; Gudmundur Johannsson

Background Patients with Addisons disease (AD) in Scandinavia have an increased risk for premature death due to cardiovascular disease (CVD). Serum lipids are important risk factors for CVD and vascular mortality. Replacement doses of hydrocortisone have historically been higher in Sweden than South Africa. The primary aim was to study the lipid profiles in a large group of patients with AD with the hypothesis that the lipid profile in patients in Sweden would be worse than in South Africa. Methods In a cross-sectional study, 110 patients with AD (55 from South Africa, 55 from Sweden) matched for age, gender, ethnicity and BMI were studied. Anthropometric measures, blood pressure, lipids, highly sensitive C-reactive protein (hs-CRP) and adiponectin were studied. Results All patients were Caucasian and the majority were women N = 36 (65.5%). Mean (standard deviation; SD) ages of the Swedish and South African patients were 52.9 (13.0) and 52.6 (14.4) years and BMI 25.3 (3.2) and 25.8 (4.1) kg/m2, respectively. The mean total daily hydrocortisone dose was greater in the Swedish patients than the South African patients, [33.0 (8.1) versus 24.3 (8.0) mg; p<0.0001]. South African patients had higher median (interquartilerange; IQR) triglycerides (TG) [1.59 (1.1–2.46) versus 0.96 (0.74–1.6) mmol/l; p<0.001], total cholesterol (TC) [6.02(1.50) versus 5.13 (0.87) mmol/l; p<0.001], LDL-C [4.43 (1.44) versus 2.75 (0.80) mmol/l; p<0.001] and median hs-CRP [2.15 (0.93–5.45) versus 0.99 (0.57–2.10) mg/L; p<0.003] and lower HDL-C [0.80 (0.40) versus 1.86 (0.46) mmol/l; p<0.001] than the Swedish patients. Approximately 20% of the patients in both cohorts had hypertension and diabetes mellitus. Conclusions South African patients with AD have worse lipid profiles and higher hs-CRP compared to their matched Swedish patients, despite lower doses of hydrocortisone. It is uncertain at this time whether these are due to genetic or environmental factors.


European Journal of Endocrinology | 2014

Body composition and bone mineral density in women with Cushing's syndrome in remission and the association with common genetic variants influencing glucocorticoid sensitivity

Oskar Ragnarsson; Camilla A. M. Glad; Ragnhildur Bergthorsdottir; Erik Almqvist; Eva Ekerstad; Håkan Widell; Bo Wängberg; Gudmundur Johannsson

OBJECTIVE Adverse body compositional features and low bone mineral density (BMD) are the characteristic of patients with active Cushings syndrome (CS). The aim of this study was to evaluate body composition and BMD in women with CS in long-term remission and the influence of polymorphisms in genes affecting glucocorticoid (GC) sensitivity on these end-points. DESIGN, PATIENTS AND METHODS This was a cross-sectional, case-controlled study, including 50 women previously treated for CS and 50 age and gender-matched controls. Median (interquartile range) remission time was 13 (5-19) years. Body composition and BMD were measured with dual-energy X-ray absorptiometry. Five polymorphisms in four genes associated with GC sensitivity were analysed using TaqMan or Sequenom single-nucleotide polymorphism genotyping. RESULTS Patients with CS in remission had increased abdominal fat mass (P<0.01), whereas BMD was not significantly different at any site between patients and controls. In patients, the NR3C1 Bcl1 polymorphism was associated with reduced total (P<0.05) and femur neck BMD (P<0.05). The polymorphism rs1045642 in the ABCB1 gene was associated with increased abdominal fat mass (P<0.05) and decreased appendicular skeletal muscle mass (P<0.05). GC replacement was associated with reduced total BMD (P<0.01), BMD at lumbar spine (P<0.05) and increased abdominal fat (P<0.01). CONCLUSION Ongoing GC replacement therapy together with polymorphisms in two genes related with GC sensitivity is associated with abdominal obesity and adverse skeletal health in patients with CS in long-term remission.


The Journal of Clinical Endocrinology and Metabolism | 2017

Visceral Fat and Novel Biomarkers of Cardiovascular Disease in Patients With Addison’s Disease: A Case-Control Study

Ragnhildur Bergthorsdottir; Oskar Ragnarsson; Stanko Skrtic; Camilla A. M. Glad; Staffan Nilsson; Maria Leonsson-Zachrisson; Gudmundur Johannsson

Context: Patients with Addisons disease (AD) have increased cardiovascular mortality. Objective: To study visceral fat and conventional and exploratory cardiovascular risk factors in patients with AD. Design: A cross‐sectional, single‐center, case‐control study. Subjects: Patients (n = 76; n = 51 women) with AD and 76 healthy control subjects were matched for sex, age, body mass index (BMI), and smoking habits. Main outcome measures: The primary outcome variable was visceral abdominal adipose tissue (VAT) measured using computed tomography. Secondary outcome variables were prevalence of metabolic syndrome (MetS) and 92 biomarkers of cardiovascular disease. Results: The mean ± standard deviation age of all subjects was 53 ± 14 years; mean BMI, 25 ± 4 kg/m2; and mean duration of AD, 17 ± 12 years. The median (range) daily hydrocortisone dose was 30 mg (10 to 50 mg). Median (interquartile range) 24‐hour urinary free cortisol excretion was increased in patients vs controls [359 nmol (193 to 601 nmol) vs 175 nmol (140 to 244 nmol); P < 0.001]. VAT did not differ between groups. After correction for multiple testing, 17 of the 92 studied biomarkers differed significantly between patients and control subjects. Inflammatory, proinflammatory, and proatherogenic risk biomarkers were increased in patients [fold change (FC), >1] and vasodilatory protective marker was decreased (FC, <1). Twenty‐six patients (34%) vs 12 control subjects (16%) fulfilled the criteria for MetS (P = 0.01). Conclusion: Despite higher cortisol exposure, VAT was not increased in patients with AD. The prevalence of MetS was increased and several biomarkers of cardiovascular disease were adversely affected in patients with AD.


Scientific Reports | 2017

Reduced DNA methylation and psychopathology following endogenous hypercortisolism – a genome-wide study

Camilla A. M. Glad; Johanna C. Andersson-Assarsson; Peter Berglund; Ragnhildur Bergthorsdottir; Oskar Ragnarsson; Gudmundur Johannsson

Patients with Cushing’s Syndrome (CS) in remission were used as a model to test the hypothesis that long-standing excessive cortisol exposure induces changes in DNA methylation that are associated with persisting neuropsychological consequences. Genome-wide DNA methylation was assessed in 48 women with CS in long-term remission (cases) and 16 controls matched for age, gender and education. The Fatigue impact scale and the comprehensive psychopathological rating scale were used to evaluate fatigue, depression and anxiety. Cases had lower average global DNA methylation than controls (81.2% vs 82.7%; p = 0.002). Four hundred and sixty-one differentially methylated regions, containing 3,246 probes mapping to 337 genes were identified. After adjustment for age and smoking, 731 probes in 236 genes were associated with psychopathology (fatigue, depression and/or anxiety). Twenty-four gene ontology terms were associated with psychopathology; terms related to retinoic acid receptor signalling were the most common (adjusted p = 0.0007). One gene in particular, COL11A2, was associated with fatigue following a false discovery rate correction. Our findings indicate that hypomethylation of FKBP5 and retinoic acid receptor related genes serve a potential mechanistic explanation for long-lasting GC-induced psychopathology.

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Gudmundur Johannsson

Federal University of Paraná

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Oskar Ragnarsson

Sahlgrenska University Hospital

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Anna G Nilsson

University of Gothenburg

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Gudmundur Johannsson

Federal University of Paraná

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