Worldwide increase in incidence of Type I diabetes--the analysis of the data on published incidence trends

Diabetologia. 1999 Dec;42(12):1395-403. doi: 10.1007/s001250051309.


Aims/hypothesis: Several reports on the incidence of Type I (insulin-dependent) diabetes mellitus have suggested that the incidence is increasing. The aim of this study was to find out whether the incidence is increasing globally or restricted to a selected populations only and to estimate the magnitude of the change in incidence.

Methods: During 1960 to 1996 37 studies in 27 countries were carried out. To fulfil the inclusion criteria the study periods ranged from 8-32 years. The temporal trend was fitted by linear regression, with the logarithm of the age-standardized incidence as the dependent variable and the calendar year as the independent variable. Then, the regression coefficient (x 100%) is approximately the average relative increase in incidence per year (as percentage).

Results: Results from the pooled data from all 37 populations showed that the overall increase in incidence was 3.0% per year (95% CI 2.6; 3.3, p = 0.0001). The statistically significant increase was found in 24 of 37 populations including all high incidence (> 14.6 per 100000 a year) populations. The relative increase was, however, steeper in the populations with a lower incidence. The correlation between logarithm of the incidence and the increase in incidence was r = -0.56, p = 0.0004.

Conclusion/interpretation: The incidence of Type I diabetes is increasing worldwide both in low and high incidence populations. By the year 2010 the incidence will be 50 per 100000 a year in Finland and also in many other populations it will exceed 30 per 100000 a year.

MeSH terms

  • Adolescent
  • Asia
  • Child
  • Child, Preschool
  • Diabetes Mellitus, Type 1 / epidemiology*
  • Europe
  • Finland
  • Humans
  • Infant
  • Infant, Newborn
  • Linear Models
  • South America
  • United States