People with Type 1 diabetes are nine times more likely to have had a virus infection than people without the condition, according to a study published in the British Medical Journal (BMJ).
Researchers from the University of New South Wales, Australia, reviewed 26 previous studies examining enterovirus infection and Type 1 diabetes, involving a total of 4,448 people. Enteroviruses belong to a common family of viruses, which usually cause the common cold or diarrhoea.
Clear relationship indicated
The review findings indicate a clear relationship. However, as the researchers significantly note, the review cannot prove that the virus causes Type 1 diabetes as the studies cannot confirm that infection occurred before the onset of Type 1 diabetes. There is now a need to assess the relationship between the virus and Type 1 diabetes over time to determine whether there really is a cause-and-effect relationship between the two.
Study is limited
"We’ve known for some time that the development of Type 1 diabetes cannot be explained by genetics alone and that some other environmental triggers must play a part," said Dr Iain Frame, Director of Research at Diabetes UK.
"Many factors have been reported as being associated with Type 1 diabetes but that is not the same as causing Type 1 diabetes and this report based on looking at a number of previous studies does not bring us much closer to pinpointing the causes of the condition.
"We do, however, welcome any new analysis that brings about a better understanding of the effect of certain viruses on the insulin-producing cells in the pancreas. It may well give us another piece of the jigsaw in working towards a better understanding of the causes of Type 1 diabetes which should in turn lead to new prevention strategies.
"The researchers themselves acknowledge the limitations of their study, however, as this type of observational analysis cannot prove cause and effect."
The research is published in theBritish Medical Journal (BMJ).