December 29, 1999
Question from Maryland, USA:
I am a school nurse in Montgomery County, Maryland. We believe we are seeing an increased incidence of type 1 in a certain cluster of schools. Do you have suggestions as to where to look for simple incidence rates among children to see if this bears further investigation? Is there any data I can collect to follow this situation?
There have been many recent reports of the slowly increasing incidence of Type�1 diabetes all over the world. These include ones from around Oxford in England, in Norway and in circumpolar groups in Canada. You could get an idea of the scope of this by using ‘Epidemiology of insulin dependent diabetes’ as a search phrase in PubMed. So far, there seem to be no clear indications of what the environmental factors are beyond the vague one of ‘westernisation’.
There have also been many narrative accounts of clusters such as you describe. For the most part these have been ascribed to statistical happenstance because of the formidable difficulty of proving the trend, which doesn’t mean to say that some of them may not have been valid. The situation is of course further complicated as investigators are able to differentiate subspecies of diabetes such as Type�1A and Type�1B.