Epidemiology of diabetes

Diabetes mellitus is a chronic disorder of glucose metabolism with serious clinical consequences. The multi-system complications of diabetes include microvascular (retinopathy, nephropathy, neuropathy) and macrovascular (ischaemic heart disease, stroke, peripheral vascular disease) endpoints. The prevalence of diabetes has been rising in the last few decades, fuelled by the global rise in the prevalence of obesity. The premature morbidity, mortality, reduced life expectancy and financial and other costs to the patient with diabetes, their carers and the health service, make it an important public health condition. The classification and diagnosis of diabetes are complex, and have been the subjects of much consultation, debate and revision stretching over the past decades. Expert committees from the World Health Organization and American Diabetes Association have formulated, converged and diverged in their position on the diagnostic criteria for diabetes, based on the measurement of fasting or 2-h post-load glucose, but most recently there has been an ongoing debate on whether glycated haemoglobin (HbA1c) should be used for diagnosing diabetes. The aetiological classification of diabetes has now been widely accepted, with type 1 and type 2 diabetes being the two main types of diabetes, and type 2 diabetes accounting for the majority (>85%) of total diabetes prevalence.