The study, the biggest of its kind, analyzed information from a register of over 4,000 people aged up to 29 years diagnosed with type 1 diabetes over a 25-year period.
The study authors, from Newcastle and Leeds Universities and Leeds Teaching Hospitals NHS Trust in the UK, carried out a sophisticated statistical analysis using information from the register on the times and places where the children and young adults were diagnosed.
A pattern emerged where ‘clusters’ of cases were found at different geographical locations and time intervals for 10 to 19 year olds. There were 6% to 7% more cases of type 1 diabetes found in 10 to 19 year olds in the clusters than would have been expected by chance.
Females with the condition were more likely to occur in clusters with 7% to 14% more cases than expected found in young girls and women aged 10 to 19 years.
This pattern, which experts call ‘space-time clustering’, is typical of conditions triggered by infections. Conditions caused by more constant environmental factors produce clusters of cases in one place over a much longer time period.
The results, published in the academic journal Diabetologia, could help towards understanding more about the causes of type 1 diabetes. It has previously been suggested that infections are linked to the development of type 1 diabetes in children who are genetically susceptible to certain environmental triggers.
“We always suspected that common infections could be a trigger for type 1 diabetes in those who are already genetically susceptible,” noted Simon O’Neill, director of care and policy at Diabetes UK. “This research provides vital evidence in supporting this link.”