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Featured researches published by Birgit Rami-Merhar.


PLOS ONE | 2014

HbA1c Variability as an Independent Risk Factor for Diabetic Retinopathy in Type 1 Diabetes: A German/Austrian Multicenter Analysis on 35,891 Patients

Julia M. Hermann; Hans-Peter Hammes; Birgit Rami-Merhar; Joachim Rosenbauer; Morten Schütt; Erhard Siegel; Reinhard W. Holl

Objective This study aimed to analyze the effect of HbA1c variability on the occurrence of diabetic retinopathy in type 1 diabetes patients. Patients and Methods 35,891 patients with childhood, adolescent or adult onset of type 1 diabetes from a large multicentre survey, the German/Austrian prospective documentation system (DPV), were analysed. Cox proportional hazard models were used to examine whether intra-individual HbA1c variability expressed as variation coefficient is an independent risk factor for the occurrence of diabetic retinopathy. Results Kaplan-Meier curves stratified by median HbA1c and variation coefficient revealed that retinopathy-free survival probability is lower when both median HbA1c and HbA1c variability are above the 50th percentile. Cox regression models confirmed this finding: After adjustment for age at diabetes onset, gender and median HbA1c, HbA1c variability was independently associated with the occurrence of diabetic retinopathy. Time-covariate interactions used to model non-proportionality indicated an effect decreasing with duration of diabetes for both median HbA1c and HbA1c variability. Predictive accuracy increased significantly when adding HbA1c variability to the Cox regression model. Conclusions In patients with type 1 diabetes, HbA1c variability adds to the risk of diabetic retinopathy independently of average metabolic control.


The Journal of Pediatrics | 2013

Diabetic Ketoacidosis at Diagnosis in Austrian Children: A Population-Based Analysis, 1989-2011

Maria Fritsch; Edith Schober; Birgit Rami-Merhar; Sabine E. Hofer; Elke Fröhlich–Reiterer; Thomas Waldhoer

OBJECTIVE To analyze the effect of a community-based, poster-focused prevention program on the frequency of diabetic ketoacidosis (DKA) at diabetes onset in Austria. STUDY DESIGN All newly diagnosed patients with diabetes ≤ 15 years of age were registered prospectively by the Austrian Diabetes Incidence Study Group. Registered data included initial blood glucose, pH, and ketonuria. DKA was defined as pH < 7.3 and severe DKA as pH < 7.1. Data between 1989 and 2011 were available. In autumn, 2009, a community-based prevention program similar to the Parma Campaign, in which posters were dispensed broadly, was initiated. The frequency of DKA at the onset of diabetes in the years 2005-2009 and 2010-2011 was compared. RESULTS During the study period, 4038 children were registered. A total of 37.2% presented with DKA; 26% had a mild and 11.2% a severe form. The frequency of DKA was negatively associated with age at onset. In the years before the intervention program, 26% had mild DKA compared with 27% after the intervention (not significant). The prevalence of severe DKA in the years before the campaign was 12% compared with 9.5% thereafter (not significant). No significant change in the DKA rate at onset by the prevention program could be found when we compared age groups <5, 5 to <10, and 10 to <15 years, neither for mild nor for severe DKA. CONCLUSION The frequency of DKA in children with newly diagnosed type 1 diabetes in Austria is high and did not change despite the efforts of a community-based information program.


Diabetes Care | 2017

Longitudinal Trajectories of Metabolic Control From Childhood to Young Adulthood in Type 1 Diabetes From a Large German/Austrian Registry: A Group-Based Modeling Approach

Anke Schwandt; Julia M. Hermann; Joachim Rosenbauer; Claudia Boettcher; Desiree Dunstheimer; Jürgen Grulich-Henn; Oliver Kuss; Birgit Rami-Merhar; Christian Vogel; Reinhard W. Holl

OBJECTIVE Worsening of glycemic control in type 1 diabetes during puberty is a common observation. However, HbA1c remains stable or even improves for some youths. The aim is to identify distinct patterns of glycemic control in type 1 diabetes from childhood to young adulthood. RESEARCH DESIGN AND METHODS A total of 6,433 patients with type 1 diabetes were selected from the prospective, multicenter diabetes patient registry Diabetes-Patienten-Verlaufsdokumentation (DPV) (follow-up from age 8 to 19 years, baseline diabetes duration ≥2 years, HbA1c aggregated per year of life). We used latent class growth modeling as the trajectory approach to determine distinct subgroups following a similar trajectory for HbA1c over time. RESULTS Five distinct longitudinal trajectories of HbA1c were determined, comprising group 1 = 40%, group 2 = 27%, group 3 = 15%, group 4 = 13%, and group 5 = 5% of patients. Groups 1–3 indicated stable glycemic control at different HbA1c levels. At baseline, similar HbA1c was observed in group 1 and group 4, but HbA1c deteriorated in group 4 from age 8 to 19 years. Similar patterns were present in group 3 and group 5. We observed differences in self-monitoring of blood glucose, insulin therapy, daily insulin dose, physical activity, BMI SD score, body-height SD score, and migration background across all HbA1c trajectories (all P ≤ 0.001). No sex differences were present. Comparing groups with similar initial HbA1c but different patterns, groups with higher HbA1c increase were characterized by lower frequency of self-monitoring of blood glucose and physical activity and reduced height (all P < 0.01). CONCLUSIONS Using a trajectory approach, we determined five distinct longitudinal patterns of glycemic control from childhood to early adulthood. Diabetes self-care, treatment differences, and demographics were related to different HbA1c courses.


Pediatric Diabetes | 2016

Insulin pump therapy in children with type 1 diabetes: analysis of data from the SWEET registry

Agnieszka Szypowska; Anke Schwandt; Jannet Svensson; Shlomit Shalitin; Roque Cardona‐Hernandez; Gun Forsander; Frida Sundberg; Carine De Beaufort; David M. Maahs; Claudio Maffeis; Stephen M.P. O‘Riordan; Iveta Dzivite Krisane; Mauro Scharf; Sofia Castro; Maia Konstantinova; Barbora Obermannova; Kristina Casteels; Damla Goksen; Júlia Galhardo; Christina Kanaka-Gantenbein; Birgit Rami-Merhar; László Madácsy

Intensified insulin delivery using multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII) is recommended in children with type 1 diabetes (T1D) to achieve good metabolic control.


The Journal of Clinical Endocrinology and Metabolism | 2014

Activating AKT2 Mutation: Hypoinsulinemic Hypoketotic Hypoglycemia

Ved Bhushan Arya; Sarah E. Flanagan; Edith Schober; Birgit Rami-Merhar; Sian Ellard; Khalid Hussain

BACKGROUND Hyperinsulinemic hypoglycemia (HH), characterized by unregulated insulin secretion, is an important cause of persistent and severe hypoglycemia. The biochemical picture of HH is hypoketotic hypo-fatty-acidemic hypoglycemia along with elevated serum insulin. Not infrequently, serum insulin might be undetectable in HH despite the presence of evidence of insulin action (suppressed ketogenesis and lipolysis). However, autonomous activity of the downstream insulin signaling pathway without the presence of the ligand (insulin) will give rise to the same clinical and biochemical picture, apart from undetectable serum insulin/C-peptide. AKT2, a serine/threonine protein kinase, is involved downstream to the insulin receptor in mediating the physiological effects of insulin. AIM We describe the second report of an activating AKT2 mutation leading to hypoinsulinemic hypoketotic hypoglycemia. PATIENTS AND METHODS The proband presented with hemihypertrophy and symptomatic hypoglycemia. Investigations confirmed evidence of insulin action, despite absence of detectable serum insulin on multiple occasions. Molecular genetic testing for common causes of HH (ABCC8, KCNJ11, and GLUD1) was negative. Sequencing of AKT2 identified a de novo mosaic c.49G→A (p.E17K) mutation, consistent with the clinical and biochemical phenotype. CONCLUSIONS This is the second report of an activating AKT2 mutation leading to hypoinsulinemic hypoketotic hypo-fatty-acidemic hypoglycemia. In patients presenting a clinical and biochemical picture of HH with undetectable serum insulin, consideration of autonomous activation of the downstream insulin signaling pathway should be made.


Clinical Immunology | 2015

Cholecalciferol supplementation improves suppressive capacity of regulatory T-cells in young patients with new-onset type 1 diabetes mellitus - A randomized clinical trial.

Gerlies Treiber; Barbara Prietl; Elke Fröhlich-Reiterer; Evelyne Lechner; Anja Ribitsch; Maria Fritsch; Birgit Rami-Merhar; Claudia Steigleder-Schweiger; Winfried Graninger; Martin Borkenstein; Thomas R. Pieber

It is unknown if cholecalciferol is able to modify defects in regulatory T cells (Tregs) in type 1 diabetes (T1D). In this randomized, double-blind, placebo controlled trial 30 young patients with new-onset T1D were assigned to cholecalciferol (70IU/kgbodyweight/day) or placebo for 12months. Tregs were determined by FACS-analysis and functional tests were assessed with ex vivo suppression co-cultures at months 0, 3, 6 and 12. Suppressive capacity of Tregs increased (p<0.001) with cholecalciferol from baseline (-1.59±25.6%) to 3 (30.5±39.4%), 6 (44.6±23.8%) and 12months (37.2±25.0%) and change of suppression capacity from baseline to 12months was significantly higher (p<0.05) with cholecalciferol (22.2±47.2%) than placebo (-16.6±21.1%). Serum calcium and parathormone stayed within normal range. This is the first study, which showed that cholecalciferol improved suppressor function of Tregs in patients with T1D and vitamin D could serve as one possible agent in the development of immunomodulatory combination therapies for T1D.


Pediatric Diabetes | 2017

Factors contributing to partial remission in type 1 diabetes: analysis based on the insulin dose‐adjusted HbA1c in 3657 children and adolescents from Germany and Austria

Katrin Nagl; Julia M. Hermann; Michaela Plamper; Carmen Schröder; Axel Dost; Olga Kordonouri; Birgit Rami-Merhar; Reinhard W. Holl

Insulin dose‐adjusted hemoglobin A1c (HbA1C, IDAA1c) correlates well with stimulated C‐peptide levels, but has not yet been evaluated in a large cohort of patients with Type 1 diabetes (T1D).


Pediatric Diabetes | 2015

Why is insulin pump treatment rarely used in adolescents and young adults with cystic fibrosis-related diabetes?

Nicole Scheuing; Klaus Badenhoop; Martin Borkenstein; Katja Konrad; Eggert Lilienthal; K Laubner; Andrea Naeke; Birgit Rami-Merhar; Angelika Thon; Dagobert Wiemann; Reinhard W. Holl

In type 1 diabetes (T1D), the use of continuous subcutaneous insulin infusion (CSII) has increased steadily in the last years. Compared with conventional insulin injection regimes, major advantages might be a nearly physiological insulin secretion, lower rates of hypoglycemia, higher flexibility in daily life, and increased quality of life. Data on CSII in cystic fibrosis‐related diabetes (CFRD) are scarce.


Diabetes Care | 2017

Use of Adjuvant Pharmacotherapy in Type 1 Diabetes: International Comparison of 49,996 Individuals in the Prospective Diabetes Follow-up and T1D Exchange Registries

Sarah K. Lyons; Julia M. Hermann; Kellee M. Miller; Sabine E. Hofer; Nicole C. Foster; Birgit Rami-Merhar; Grazia Aleppo; Jochen Seufert; Linda A. DiMeglio; Thomas Danne; David M. Maahs; Reinhard W. Holl

The majority of those with type 1 diabetes (T1D) have suboptimal glycemic control (1–4); therefore, use of adjunctive pharmacotherapy to improve control has been of clinical interest. While noninsulin medications approved for type 2 diabetes have been reported in T1D research and clinical practice (5), little is known about their frequency of use. The T1D Exchange (T1DX) registry in the U.S. and the Prospective Diabetes Follow-up (DPV) registry in Germany and Austria are two large consortia of diabetes centers; thus, they provide a rich data set to address this question. For the analysis, 49,996 pediatric and adult patients with diabetes duration ≥1 year and a registry update from 1 April 2015 to 1 July 2016 were included (19,298 individuals from 73 T1DX sites and 30,698 individuals from 354 DPV sites). Adjuvant medication use (metformin, glucagon-like peptide 1 [GLP-1] receptor agonists, dipeptidyl peptidase 4 [DPP-4] inhibitors, sodium–glucose cotransporter 2 [SGLT2] inhibitors, and other noninsulin diabetes medications including pramlintide) was extracted from …


Diabetes Care | 2013

Predicting the Optimal Basal Insulin Infusion Pattern in Children and Adolescents on Insulin Pumps

Paul-Martin Holterhus; Jessica Bokelmann; Felix G. Riepe; Bettina Heidtmann; Verena M. Wagner; Birgit Rami-Merhar; Thomas Kapellen; Klemens Raile; Wulf Quester; Reinhard W. Holl; Austrian DPV-Initiative

OBJECTIVE We aimed at developing and cross-validating a mathematical prediction model for an optimal basal insulin infusion pattern for children with type 1 diabetes on continuous subcutaneous insulin infusion therapy (CSII). RESEARCH DESIGN AND METHODS We used the German/Austrian DPV-Wiss database for quality control and scientific surveys in pediatric diabetology and retrieved all CSII patients <20 years of age (November 2009). A total of 1,248 individuals from our previous study were excluded (dataset 1), resulting in 6,063 CSII patients (dataset 2) (mean age 10.6 ± 4.3 years). Only the most recent basal insulin infusion rates (BRs) were considered. BR patterns were identified and corresponding patients sorted by unsupervised clustering. Logistic regression analysis was applied to calculate the probabilities for each BR pattern. Equations were based on both independent datasets separately, and probabilities for BR patterns were cross-validated using typical test patients. RESULTS Of the 6,063 children, 5,903 clustered in one of four major circadian BR patterns, confirming our previous study. The oldest age-group (mean age 12.8 years) was represented by 2,490 patients (42.18%) with a biphasic dawn-dusk pattern (BC). A broad single insulin maximum at 9–10 p.m. (F) was unveiled by 853 patients (14.45%) (mean age 6.3 years). Logistic regression analysis revealed that age, to a lesser extent duration of diabetes, and partly sex predicted BR patterns. Cross-validation revealed almost identical probabilities for BR patterns BC and F in the two datasets but some variation in the remaining two BR patterns. CONCLUSIONS Reconfirmation of four key BR patterns in two very large independent cohorts supports that these patterns are realistic approximations of the circadian distribution of insulin needs in children with type 1 diabetes. Prediction of an optimal pattern a priori can improve initiation and clinical follow-up of CSII in children and adolescents. In addition, these BR patterns represent valuable information for insulin-infusion algorithms in closed-loop CSII.

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Edith Schober

Medical University of Vienna

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Sabine E. Hofer

Innsbruck Medical University

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Maria Fritsch

Medical University of Vienna

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