[Is prevention of diabetes mellitus possible?]

Despite recent progress in therapy and management of diabetes mellitus, diabetes remains a serious disease with life-threatening complications. It is by far the most common metabolic disease and affects 5% of the population in industrialized countries. Noninsulin-dependent diabetes mellitus (NIDDM) is a complex disorder characterized by insulin resistance and impaired insulin secretion and is associated with an increased risk of coronary heart disease, peripheral vascular disease, arterial hypertension and dyslipidemia. Predisposing factors for NIDDM are obesity and a family history of diabetes. Greater physical activity has been associated inversely with the prevalence of NIDDM in several cross-sectional studies. Physical activity increases the sensitivity to insulin, and regular endurance exercise can induce and maintain weight loss, improve glucose tolerance and ameliorate most of the abnormalities in the metabolic syndrome. Type I diabetes mellitus arises as a consequence of immunologically mediated pancreatic islet beta-cell destruction in genetically susceptible individuals. It is an insidious process that may occur over years. During the stage of disease evolution (prediabetes), individuals may be identified by the presence of immunological markers and a decline of beta-cell function. The autoimmune nature of the disease process has led to attempts to stop this process by immune intervention strategies. A variety of immune interventions has been used, some immunosuppressive and some immunomodulatory. Several screening programs are used in order to identify high-risk subjects (i.e. first-degree relatives of individuals with type I diabetes) who may benefit from an early intervention. The ultimate goal of all these efforts is to prevent the development of overt type I diabetes mellitus in those at risk for the disease, using strategies that are both safe and specific. This review summarizes the results of the various studies conducted to date and outlines the approaches currently being tested.