Type 1 diabetes on the rise

In the last 25 years, the incidence of type 1 diabetes has doubled in children in Finland, and studies suggest rates are rising fast in other countries, too, researcher Jaakko Tuomilehto of the University of Helsinki reported Friday afternoon here at the ADA's Scientific Sessions. In Finland, which holds the world's record for type 1 incidence at 41 cases per 100,000 people, the average rose from 31.4/100,000 in 1980 to 64.2/100,000 in 2005, and the pace of increase has been speeding up since the early 1990s.

Between 1980-91, type 1 incidence rose at the rate of 1.6% per year, but between 1992 and 2005, the rate more than doubled to 4.1% per year. It differed by age group, jumping 4.7% per year in the 0-4 year-old age group, compared to 2.7% in the 5-9 and 1.7% in 10-14 year-olds. "The highest incidence now is in children age 1-5,'' he said, and "the incidence has started to increase faster.'' Though the data are specific to Finland, he said, other studies show similar trends in Northern Ireland, Austria, Poland and Slovakia. "The incidence is probably increasing globally,'' he said.

A second report by researcher Jeffrey A. Johnson of the University of Alberta, Canada, echoed that. Dr. Johnson and colleagues found the prevalence of diabetes under age 20 increased by nearly 50% in the last decade, from about 19 per 10,000 in 1995 to 28 per 10,000 in 2006. The rise was most dramatic in younger children, leaping 93% in the 1-4 year-old age group; 51% for 5-9 years, 42% for 10-14 years and 30% for 15-19 years during that period.  The data do not differentiate between type 1 and type 2 diabetes, he said, but "the incidence is rapidly increasing and it is likely to be due to an increased incidence of type 1 diabetes.''

Why it's happening is not known, but it's more than a shift to earlier diagnosis, said Dr. Tuomilehto. Whatever it is, it bodes ill for the future. In Finland, experts had predicted the incidence of type 1 would reach 50 per 100,000 by 2010. They've already passed that milestone, and are now predicting 80 per 100,000 by that year.

The trends for type 1 diabetes in the U.S. are unclear.  Some investigators in the U.S. have reported an increasing rate of type 1 diabetes in the populations they study, while others have not.  Data collection has traditionally not been as comprehensive in the U.S. as it is in countries with nationalized health care, like Finland.  But a study launched by the Centers for Disease Control and Prevention a few years ago, "SEARCH for Diabetes in Youth", may give is a better picture of the trends in the U.S. in coming years.

Comments

[Melitta]

Keep in mind, these studies are only looking at rates of Type 1 diabetes in children, when in fact according to the CDC the majority of new Type 1 cases are seen in those over age 20. You can't get a full picture by looking at the minority of Type 1s.