Does the secular increase in body mass in children contribute to the increasing incidence of type 1 diabetes?

BACKGROUND

The incidence of type 1 diabetes in children has increased in most developed countries after World War II, and simultaneously, normal children have experienced accelerated weight gain and growth.

OBJECTIVE

We set out to explore whether any relationship can be seen between the incidence of childhood type 1 diabetes and changes in linear growth and body mass in Finnish children over a 12-yr period.

METHODS

Incidence rates for type 1 diabetes in Finnish children under the age of 15 yr were obtained from the National Central Drug Registry. The rates were averaged for 3-yr intervals over the 15-yr period 1979-1993 and related to data on mean height, weight, and body mass index (BMI) in 15-yr-old children generated for the years 1980, 1983, 1986, 1989, and 1992 by the 'Cardiovascular Risk in Young Finns' study.

RESULTS

There was a positive correlation between the incidence of childhood type 1 diabetes and mean heights (r = 0.84; p = 0.039), mean weights (r = 0.85; p = 0.036), and mean BMIs (r = 0.87; p = 0.028) in 15-yr-old children over the 12-yr study period.

CONCLUSIONS

This observation suggests that accelerated linear growth and increasing body mass may contribute to the rising incidence of childhood type 1 diabetes seen in most developed countries since World War II. This effect might be mediated through increased beta-cell stress induced by hyperinsulinemia and decreased insulin sensitivity, associated with rapid linear growth and obesity.