What is Diabetes?

Diabetes is a group of carbohydrate, protein, and fat metabolism disorders caused by absolute or relative insulin deficiency and/or insulin utilization disorder, with hyperglycemia as the main sign.

The typical clinical manifestations of diabetes are polydipsia, polyuria, polyphagia, and weight loss, as well as high blood sugar and glucose in urine. The long-term course of the disease can cause multi-system damage, leading to chronic progressive lesions, functional impairment and failure of tissues and organs such as eyes, kidneys, nerves, heart, and blood vessels.

Severe illness or stress can cause acute and severe metabolic disorders. Diabetes is an important cause of cardiovascular and cerebrovascular diseases, death, amputation, blindness, renal failure, and heart failure.

Incidence of Diabetes

According to the latest data from the International Diabetes Federation (IDF), the global prevalence of diabetes among people aged 20 to 79 in 2021 is estimated to be 10.5%, or about 536.6 million people with diabetes. It is expected that by 2045, the number of people with diabetes worldwide will increase to 783.2 million, and the prevalence will rise to 12.2%. This means that more than one in ten adults in the world currently have diabetes, and this number will continue to grow rapidly in the future.

Among the different income groups, the prevalence of diabetes is highest in middle-income countries. Compared with the 9th Edition of Diabetes Atlas released by IDF, the global prevalence of diabetes has increased by 12.9% overall, and there have been increases in many regions. The absolute increase in the number of people with diabetes is expected to occur mainly in middle-income countries by 2045, which is related to the growth and aging of the population in these countries and accelerated urbanization.

It is worth noting that these estimates do not distinguish by diabetes type. However, the vast majority of people with diabetes have type 2 diabetes, and the expected increase by 2045 is also mainly type 2 diabetes. This reflects differences in the pathophysiology of type 1 and type 2 diabetes, as well as the impact of global environmental change, such as increases in overweight, physical inactivity, and changes in dietary habits, which are all associated with the occurrence of type 2 diabetes.

Types of Diabetes

Type 1 diabetes: rare, often occurring in childhood and adolescence, accounting for less than 1% of diabetes patients in China. Etiology can be divided into immune-mediated and idiopathic (pathogenesis unknown).

Type 2 diabetes: common, accounting for more than 95% of diabetes patients in China, causes include insulin resistance, progressive insulin deficiency, or both. Special types of diabetes: including diabetes caused by genetic defects in pancreatic beta cell function, diabetes caused by genetic defects in insulin action, diabetes caused by exocrine pancreatic diseases, diabetes caused by other endocrine diseases, diabetes caused by drugs or chemicals, diabetes caused by infection, uncommon immune-mediated diabetes, and other genetic syndromes related to diabetes. Gestational diabetes: no diabetes before pregnancy and early pregnancy, high blood sugar first found after 24 weeks of pregnancy.