More than just type 1 or type 2: DiMelli study points to different forms of diabetes

Neuherberg - The DiMelli study examines the different phenotypes of diabetes mellitus in relation to their immunological, metabolic and genetic profiles. Although the formation of autoantibodies is associated with specific clinical features such as metabolic markers, the various forms of diabetes cannot be clearly delineated on the basis of this association, and in many cases there is overlapping. The results of the study have now been published in the latest edition of the scientific journal PLOS ONE. In it, the scientists involved stress the importance of their findings towards developing a full understanding and a clear classification of diabetes.

The DiMelli (Diabetes Mellitus Incidence Cohort Registry) study examines the frequency and characteristics of diabetes phenotypes in children and young adults below the age of 20. The study was commissioned to investigate the increasing incidence of diabetes mellitus, particularly in childhood and early adulthood. The project is funded by the German Center for Diabetes Research (DZD). Bioprobe measurements were performed centrally by the Central Medical Laboratory (LMZ) at the Helmholtz Zentrum München (HMGU) so as to guarantee the high quality and comparability of laboratory parameters. The study is based on the DiMelli Bavarian Diabetes Register, the only register of its kind in Germany, which collects data on biological parameters in the blood of newly diagnosed diabetics as well as their phenotypic characteristics, i.e. their physical symptoms and features. A questionnaire is used to identify the characteristics of the form of the disease occurring in the patient in question such as body weight and weight changes as well as blood sugar levels, residual insulin production and other biomarkers.

The team of scientists headed by Professor Anette-Gabriele Ziegler, Dr. Katharina Warncke and Dr. Andreas Beyerlein from the Institute of Diabetes Research (IDF) at the Helmholtz Zentrum München, the Diabetes Research Group at the Technical University of Munich (TUM), the Children’s Hospital in Munich-Schwabing and the Department of Pediatrics at the Klinikum rechts der Isar, Technical University of Munich, have now evaluated the initial data from the DiMelli study.

Between April 2009 and June 2012, 630 people were included in the register. Of that number, 522 exhibited two or more diabetes-specific antibodies while 64 participants in the study displayed one antibody. In 44 of the participants no antibodies were found. The existence of antibodies characterizes autoimmune type 1 diabetes, whereas type 2 diabetes occurs without any specific immunological reaction. Although the participants with and without diabetes-specific autoantibodies displayed different characteristics in terms of body weight, weight loss and residual insulin production function, as expected, the phenotypic features could not be clearly assigned to specific disease types. This means that the formation of autoantibodies does not go hand-in-hand with a clearly separable combination of other blood values and clinical characteristics.

The authors thus conclude that the latest scientific findings no longer support such a rigid classification of diabetes. Rather there appears to be a continuum of forms and a mixture of diabetes phenotypes. “In order to be able to introduce the right steps in treatment and to offer patients accurate information about their disease, it is essential to refine the criteria for differentiating and diagnosing the different forms of diabetes,” Professor Ziegler explains. “Further studies are now required to shed light on the long-term development of the phenotypes, the distribution of different types of diabetes and the way in which their features present themselves in adult patients.”

As German Research Center for Environmental Health, Helmholtz Zentrum München pursues the goal of developing personalized medical approaches for the prevention and therapy of major common diseases such as diabetes mellitus and lung diseases. To achieve this, it investigates the interaction of genetics, environmental factors and lifestyle. The Helmholtz Zentrum München has about 2,100 staff members and is headquartered in Neuherberg in the north of Munich. Helmholtz Zentrum München is a member of the Helmholtz Association, a community of 18 scientific-technical and medical-biological research centers with a total of about 34,000 staff members. www.helmholtz-muenchen.de

The German Center for Diabetes Research (DZD) brings together experts in the field of diabetes research and interlinks basic research, epidemiology and clinical applications. Members are the German Diabetes Center in Düsseldorf, the German Institute of Human Nutrition (DIfE) in Potsdam-Rehbrücke, Helmholtz Zentrum München – German Research Center for Environmental Health, the Paul Langerhans Institutes of the University Hospital Carl Gustav Carus in Dresden and the University of Tübingen, as well as the Gottfried Wilhelm Leibniz Association and the Helmholtz Association of German Research Centres. The objective of the DZD is to find answers to open questions in diabetes research by means of a novel, integrative research approach and to make a significant contribution to improving the prevention, diagnosis and treatment of diabetes mellitus. www.dzd-ev.de

The Institute of Diabetes Research (IDF1) focuses on the pathogenesis and prevention of type 1 diabetes and gestational diabetes. For this purpose, it is investigating the molecular mechanisms of disease development, in particular the interaction of the environment, genes and the immune system. The aim is to identify markers for early diagnosis and the development of therapies to prevent and cure diabetes. IDF1 is part of the Diabetes Research Department.