Testing children at high risk of type 1 diabetes for islet cell antibodies at 2 and 6 years of age may predict the onset of type 1 diabetes by 15 years of age, according to a study of nearly 7000 children, which analyzed data from five international prospective studies.¹

Researchers pooled data of 24,662 children aged 2 years or younger from the Type 1 Diabetes Prediction and Prevention (DIPP) Study in Finland (Finland), the Diabetes Prediction in Skåne (DiPiS) study conducted in Sweden, the German multicenter BABYDIAB study and the US Diabetes Autoimmunity Study in the Young (DAISY) and the Diabetes Evaluation in Washington (DEW-IT) trials to form a Type 1 Diabetes Intelligence (T1DI) group. The present study included 6722 participants, who were genetically at risk. The islet autoantibodies, which included antibodies against glutamic acid decarboxylase (GAD65), insulinoma antigen 2 (IA-2) and insulin, were measured yearly. They were followed up till the age of 15 years or development of type 1 diabetes. The study aimed to find out the sensitivity and positive predictive value (PPV) of detected islet autoantibodies in diagnosing clinical type 1 diabetes at 2 and 6 years of age.

Results published in The Lancet Diabetes & Endocrinology show that out of the 6722 children, 672 developed type 1 diabetes by 15 years of age, while 6050 did not. Testing for the islet cell autoantibodies at 2 and 6 years of age yielded a sensitivity of 82% and PPV of 79% for diabetes by the age of 15 years. The study also showed that children who were diagnosed with type 1 diabetes in due course of time, already had antibodies at the median age of 4.5 years.  

Children who tested positive for multiple islet cell autoantibodies at 2 years had 55% higher risk of developing type 1 diabetes by 6 years of age, while this risk was 31% in those who were positive for a single autoantibody. The risk of type 1 diabetes was 83% among children who were positive for multiple islet cell autoantibodies at 6 years, regardless of them testing positive or negative at 2 years. A negative test at 2 years increased the risk of onset of type 1 diabetes by 39% until the age of 15 years. On the other hand, a positive test at 2 years of age increased this risk by 70%.²

The findings of the study have public health implications as they demonstrate the feasibility of predicting development of clinical type 1 diabetes by 15 years of age by testing for islet cell antibodies at two ages (2 and 6 years of age) rather than at one age. Early identification of children at risk of future type 1 diabetes allows for timely implementation of preventive measures and monitoring for progression to clinical type 1 diabetes. Educating parents about the disease can help them to recognize the early signs and symptoms of hyperglycemia and preclude complications such as diabetic ketoacidosis. However, the authors also suggest that this strategy “might require adjustment by country on the basis of population-specific disease characteristics”.¹

References

1. Mohamed Ghalwash, et al; Type 1 Diabetes Intelligence Study Group. Two-age islet-autoantibody screening for childhood type 1 diabetes: a prospective cohort study. Lancet Diabetes Endocrinol. 2022 Jul 5;S2213-8587(22)00141-3. doi: 10.1016/S2213-8587(22)00141-3.
2. Childhood Type 1 Diabetes Tests Suggested at Ages 2 and 6 - Medscape - Jul 12, 2022.