Childhood obesity linked to increased risk of 4 subtypes of adult-onset diabetes

According to the new research conducted by Yuxia Wei, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden and published in Diabetologiac and the first of it's kind, childhood obeity is associated with an increased risk of four of the five recently proposed subtypes of adult-onset diabetes. 

A ground-breaking study in 2018 identified five novel subtypes of adult-onset diabetes differ in their clinical characteristics, complications and genetic backgrounds. They include: severe autoimmune diabetes (SAID, including type 1 diabetes and latent autoimmune diabetes in adults [LADA]) and four subtypes of type 2 diabetes (severe insulin-deficient diabetes [SIDD], severe insulin-resistant diabetes [SIRD], mild obesity-related diabetes [MOD] and mild age-related diabetes [MARD]). SIDD, SIRD, MOD and MARD are currently collectively classed as type 2 diabetes. It is unclear if they also differ in modifiable risk factors.

It should be noted that the victims of childhood obesity are rising worldwide. Childhood adiposity has been linked to several chronic diseases including type 1 diabetes in children and type 2 diabetes; however, it has never been investigated in relation to the recently proposed subtypes of adult-onset diabetes. In this study, the authors aimed to compare the effects of childhood body size on the risk of different diabetes subtypes occurring in adults. They used a statistical technique known as Mendelian randomization (MR), where genetic information is used to study the link between an environmental risk factor and a disease, while accounting for the influence of other risk factors.

The study is somehow reliable because the authors used data from the UK Biobank for their study. They extracted summary statistics for childhood body size from a genome-wide association study of 453,169 European participants who self-reported body size (thinner, about average, and plumper/bigger) at the age of 10 years in the UK Biobank study. The study incorporated more than 200 genetic mutations as indicators of childhood body size and linked them to LADA (267) and the other types of diabetes (275).

"Our analyses indicate that childhood obesity is a risk factor for four of the five proposed novel subtypes of adult-onset diabetes, regardless of whether they are classified as being primarily characterized by autoimmunity, insulin deficiency, insulin resistance or obesity. Childhood obesity appears to be a risk factor for essentially all types of diabetes in adults, except for mild age-related diabetes. This stresses the importance of preventing obesity in children," the authors concluded.