Types of diabetes
Diabetes is in fact an umbrella term for several different diseases which are all characterised by increased blood sugar levels as a result of a decrease in the production of insulin, impaired effect of the produced insulin, or both. Previously, it was common to divide diabetes into type 1, which mainly affects children, and type 2, which is most common among adults. However, the researchers behind the ANDIS and ANDiU registries, which ESTRID collects its participants from, propose a more nuanced picture of diabetes with five different categories of diabetes affecting adults and young adults . One of these categories include a type of diabetes called LADA (latent autoimmune diabetes in adults).
Diabetes is a common disease: around 7 percent of the adult Swedish population is affected . It is also one of the fastest growing diseases in the world. According to the World Health Organization (WHO), the global prevalence has doubled since the 1980's and the number of affected individuals has increased four-fold . One reason for this increase is that a sedentary lifestyle and overweight have become more common worldwide. In the long term, diabetes can lead to complications affecting the eyes, kidneys, heart and blood vessels. With the division into several different subcategories, the aim is to offer patients a more individualized treatment. Read more about the different types of diabetes on the ANDIS website (in Swedish).
LADA (latent autoimmune diabetes in adults) is a type of diabetes characterized by both type 1- and type 2-like features. According to the ANDIS registry at Lund University, LADA makes up for around 5 percent of all diabetes in adults, which makes it more common than type 1 diabetes among this group . It is similar to type 1 diabetes in so far that is an autoimmune type of diabetes. The disease is progressing more slowly than in type 1 patients and unlike these patients, LADA patients ususally manage without insulin treatment for some time . LADA also displays type 2-like features since disease onset is in adults and it is characterised by reduced insulin sensitivity .
Type 2 diabetes is a hereditary disease but the risk of developing type 2 is also affected by lifestyle factors . This type of diabetes is primarily characterised by reduced insulin sensitivity, so called insulin resistance, which can emerge as a consequence of a sedentary lifestyle, overweight or smoking. Individuals with a family history of diabetes in combination with one or several risk factors are at particular risk of developing the disease. Type 2 patients make up 85% of all diabetes cases .
Type 1 diabetes is just like LADA an autoimmune type of diabetes where the immune system attacks the insulin producing cells in the pancreas. The result is that the insulin production ceases and this is why individuals with type 1 diabetes are dependent on insulin treatment. The disease is hereditary but the environment is also believed to be of importance for the development. There are few known risk factors but viral infections early in life are believed to increase the risk.
Facts about LADA and type 2 diabetes
- Type 2 diabetes onset is primarily in adults but it can also be present in young adults and children.
- Disease onset for LADA is in adults only. A criterium for both LADA and type 2 patients in ESTRID is that the individual has turned 35 years at diagnosis.
- Type 2 diabetes is characterised by insulin resistance, which causes a decrease in the cells' capability to react to the insulin being produced.
- LADA carries features of both type 1 and type 2 diabetes. It is similar to type 1 in so far that it is autoimmune, causing the immune system to attack the insulin producing cells, which results in insulin deficiency. LADA is also, like typ 2 diabetes, characterised by insulin resistance.
- The antibodies attacking the insulin producing cells are called GADA and are prevalent both in individuals with LADA and type 1 diabetes but not in individuals with type 2 diabetes. LADA patients can have a higher or lower level of these antibodies. A higher level makes the diabetes more type 1-like, while a lower level makes it more type 2-like.
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- Lunds universitet. ANDIS- Alla Nya Diabetiker i Skåne.
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