Family history of diabetes increases risk of diabetes type LADA, study reports

People with a family history of diabetes have a greater chance of developing a rare form of type 1 diabetes, say Swedish researchers.
In a new trial the risk of Latent Autoimmune Diabetes of Adults (LADA) was shown to be greater when family members had type 1 diabetes, and still elevated when relatives had type 2 diabetes.
LADA is a form of type 1 diabetes which emerges in adults. It normally develops slower than type 1 diabetes does in children and the condition has previously been misdiagnosed as type 2 diabetes.
It had already been established that having family members with type 1 diabetes or 2 diabetes can increase the risk of people developing either condition. Now scientists from the Institute of Environmental Medicine at Karolinska Institutet have shown that family history of both types of diabetes could increase the risk of LADA.
“Having both [type 1 diabetes] and [type 2 diabetes] in the family is associated with the risk of [latent autoimmune diabetes in adults], and the strong association with [family history of type 1 diabetes] suggests that genes related to autoimmunity are more influential in the development of [latent autoimmune diabetes in adults] than those related to [type 2 diabetes],” said the researchers.
The findings were made following an examination of a previous study based on more than 3,000 people, which included 378 adults with LADA.
Those with LADA were found to be more likely to a carry a high-risk genotype known as DR4-DQ8, which was also prevalent in a significant number of participants who reported a family history of type 1 diabetes.
LADA patients were less likely to carry a low-risk genotype called DRX/X compared to those with type 2 diabetes, indicating prospective genetic differences between the conditions.
The study team concluded that LADA risk was two-fold higher in participants with first- or second-degree relatives with diabetes, and this risk continued to increase with the number and closeness of the relative.
“Given this situation, it is noteworthy that, with regard to lifestyle, studies to date indicate that [latent autoimmune diabetes in adults] shares several risk factors with [type 2 diabetes], including smoking, alcohol consumption (protective) and low birth weight. Taken together, these findings indicate that [latent autoimmune diabetes in adults] development is promoted by genes related to autoimmunity and by lifestyle factors that increase insulin resistancei.”
The findings were published in the journal Diabetes and Metabolism.