New insights into adult-onset type 1 diabetes

Having a first-degree relative with the condition significantly increases the risk of developing type 1 diabetes as an adult and the risk is higher if the relative developed diabetes early.

Type 1 diabetes (T1D), a chronic disease affecting millions of young people worldwide, is not confined to childhood. Up to half of all cases are diagnosed in adulthood, and there is a need to understand the factors that contribute to the development of T1D in adults.

A comprehensive nationwide cohort study conducted by researchers at Karolinska Insitutet investigated the familial and heritability aspects of T1D in different age groups. Researchers analysed data from more than 2.9 million people born between 1982 and 2010, using linkage to family members through the Multi-Generation Register.

The study found that having a first-degree relative with T1D significantly increased the risk of developing the disease, with higher hazard ratios observed for childhood-onset T1D compared to adult-onset T1D. Interestingly, the risk was lower if the relative developed T1D in adulthood rather than childhood.

The research also showed that adult-onset T1D had weaker familial aggregation and lower heritability compared to childhood-onset T1D. This suggests a greater influence of environmental factors in the development of adult T1D, highlighting the importance of identifying and addressing these factors.

The findings underscore the complexity of T1D aetiology and highlight the need for targeted interventions to reduce environmental risk factors, particularly in adults at risk of developing the disease.

First author of the new study is Yuxia Wei, doctoral researcher in the ESTRID group.


Familial aggregation and heritability of childhood-onset and adult-onset type 1 diabetes: a Swedish register-based cohort study.
Wei Y, Liu S, Andersson T, Feychting M, Kuja-Halkola R, Carlsson S
Lancet Diabetes Endocrinol 2024 Mar;():

Miranda Beck