Epidemiology of type 1 and type 2 diabetes. The added value of diabetes registries for conducting clinical studies: the Belgian paradigm.
Diabetes registries have documented that the lifetime risk of diabetes amounts to at least 10% in the western world. Moreover the prevalence of type 2 diabetes is increasing worldwide especially in developing countries. Furthermore there is a secular trend toward earlier clinical manifestation of both type 1 and type 2 diabetes. In the absence of a permanent cure for primary diabetes the present estimated number of at least 150 million diabetic patients worldwide is expected to double within the next 20 years. Consequently a sharp increase in the global burden of chronic diabetes complications is to be feared in the coming decades. Therefore it is absolutely mandatory to intensify research efforts aiming at identifying the etiological factors involved and designing effective strategies for prediction and prevention of the disease and its devastating complications. Diabetes registries constitute instruments of choice to conduct such studies because they are able to collect standardised clinical, demographic and biological information from sufficiently large representative groups of patients and risk groups such as first degree relatives. Since 1989, the Belgian Diabetes Registry is studying all types of diabetes presenting before age 40 in Belgium and provides a paradigm of how diabetes registries may also contribute to the advancement of knowledge on disease heterogeneity, etiology, prediction and prevention.