May 27, 2009 -- The incidence of type 1 diabetes among very young children will double from 2005 levels in a little over a decade if present trends continue, a new study shows.
The prediction is based on type 1 diabetes trends in Europe, but experts say there is every reason to believe that the U.S. will see a similar dramatic increase in the disease.
They are also convinced that environmental exposures are driving the increase, but it is far from clear what those exposures are.
The most common age of diagnosis has been the early teen years, but epidemiologist Christopher C. Patterson, PhD, of Ireland's Queen's University, tells WebMD that the burden may be shifting toward younger children.
"We are likely to see more children with severe diabetes complications presenting at earlier ages if we fail to recognize and adequately treat disease in very young patients," he says.
In the latest issue of TheLancet, Patterson and colleagues concluded that rates of type 1 diabetes among children and young teens are increasing faster than previous predictions suggested.
Patterson and colleagues analyzed data from European registries, which included information on more than 29,000 children with type 1 diabetes, enrolled between 1989 and 2003.
They found that:
- The overall increase in incidence of type 1 diabetes was 3.9% per year.
- The increase was greatest among children under 5, who saw increases of 5.4% per year compared to an annual increase of 4.3% among children between the ages of 5 and 9 and 2.9% among children between the ages of 10 and 14.
- If present trends continue, total cases of disease are projected to rise by 70% by 2020 and rates among children under 5 will double.
Reasons for Increase in Type 1 Diabetes
Since the increases are occurring so quickly, it is likely that environmental influences are driving the trend, Patterson says.
Researchers are examining a wide range of possible environmental triggers, including early-life diet, viral infection, and even C-section delivery. But they still have more questions than answers.
"Being born to an older mom and C-section birth seem to be associated with slight increases in risk, but neither one of these is sufficient to explain the increases we are seeing," he says.
University of Colorado epidemiologist Dana Dabelea, MD, PhD, tells WebMD that one of the key areas of interest is rapid early growth due to improved early-life nutrition.
Dabelea is a co-investigator on the SEARCH for Diabetes in Youth Study, which is following children with type 1 and type 2 diabetes in different areas in the U.S. in an effort to better understand diabetes trends in non-adults.
In 2007, Dabelea and colleagues reported higher-than-predicted rates of type 1 diabetes. The increase was most pronounced among non-Hispanic white children.
In an editorial accompanying the new study, Dabelea called for more research on type 1 and type 2 diabetes in children.
"It is imperative that efforts directed at surveillance of diabetes in young people continue and expand, not only to understand its complex etiology, but also because of the increasing public health importance," she writes.