Every year on April 7th, the WHO commemorates its foundation in 1948 with the World Health Day and dedicates a certain health topic of global importance to this day. This year, diabetes mellitus is in focus (“Beat diabetes”). The reason for this is the growing number of diabetes patients, especially in middle and low income countries. In 2008, approximated 347 million people had diabetes. Until 2030 diabetes will belong to the seven worldwide most frequent causes of death as predicted by the WHO.
In diabetes patients either the pancreas does not produce enough insulin anymore or the body is not able to use insulin appropriately. The hormone is required by cells to take up glucose from the blood in order to metabolise the sugar into energy. Without insulin the blood sugar level is constantly high – the main feature of diabetes mellitus. The high blood sugar concentration influences further metabolic processes and impairs major organ systems leading to e. g. heart infarction, destruction of nerves, kidney failure and blindness.
Types of diabetes mellitus
There exist two major forms of diabetes. Patients with type 1 diabetes do not produce enough insulin or any at all and depend on insulin supply, e.g. through injections. This form is attributed to a dysregulation of the immune system leading to the destruction of insulin producing cells (autoimmune disease). Accordingly, autoantibodies against pancreatic cells can be detected in serum samples of 80% to 90% of type 1 diabetes patients. Specific target antigens of these antibodies are the enzymes glutamate decarboxylase (GAD65) and tyrosine phosphatase (IA2) as well as insulin and zinc transporter 8 (ZnT8A), among others. Usually, type 1 diabetes manifests during infancy/adolescence. Since antibody prevalences vary according to the age, different combinations of serological antibody tests are suggested for the diagnosis of type 1 diabetes in children under or over 10 years of age (see for example Seissler and Scherbaum, 2005). The second major form is type 2 diabetes which is characterized by an insulin resistance. Although the body still produces insulin, the cells decreasingly respond to the hormone – it loses its effect. Often, the development of type 2 diabetes is associated with an unhealthy diet, obesity and a lack of physical activity. Thus, the disease commonly does not manifest until adulthood. Depending on its clinical development, the patients do not rely on insulin and may be successfully treated with a dietary change and/or tablets. In diagnostics, it is important to differentiate between type 2 diabetes and LADA, the Latent Autoimmune Diabetes in Adults. LADA is a rare form of type 1 diabetes which appears in adulthood for the first time despite of its autoimmune origin and is therefore frequently misinterpreted as type 2 diabetes. Distinction of the two diabetes forms is important for therapy and can be achieved through testing for anti-GAD antibodies. These are characteristic for LADA but absent in type 2 diabetes.
A special form of diabetes mellitus is diabetes gestationis. The high blood sugar levels arise during pregnancy and usually normalise after giving birth. The secretion of pregnancy hormones, which influence the glucose metabolism, is the cause of this diabetes form.
Key messages of the World Health Day 2016
The WHO campaign is supposed to raise the perception of diabetes as a severe disease with growing impact on global health systems. Further messages shall be that 1) type 2 diabetes is preventable in many cases through a healthy life style and 2) diabetes patients (type 1 and 2) can be effectively treated when correctly diagnosed and thus can avoid severe complications.