The incidence of type 1 diabetes in Finland is the highest in the world. For a long time, the incidence of the disease has been following a worryingly upward trend in Finland and in other countries with a high incidence rate for diabetes, particularly among children under 5 years of age.
The previous study on the incidence of diabetes in Finland, carried out from 2006 to 2011, provided interesting indications of the incidence rate reaching a plateau. In fact, the incidence has begun to decrease since 2011, as described in the study published in the Diabetes Care journal.
The new study utilised data from the Finnish Pediatric Diabetes Register to determine the trends associated with the incidence of type 1 diabetes in children under 15 years of age in 2003–2018. A total of 7,871 individuals who were younger than 15 developed type 1 diabetes in Finland during this period.
In the early years of the study period, in 2003–2006, the overall incidence rate was 57.9 cases per 100,000 person years. Compared to the final years of the study period, the overall incidence rate was found to have dropped to 52.2 cases per 100,000 person years in 2015–2018.
The most significant decrease was observed in children under 5 years of age, among whom the incidence rate dropped from 51.1 in 2003–2006 to 39.3 in 2015–2018.
In children between 5 to 9 years of age, a decrease was seen in girls only, while the incidence rate for 10- to 14-year-olds did not significantly change during the study period.
The decrease in incidence in the youngest age group is a significant new finding, encouraging researchers to reflect on possible changes in the environmental factors associated with early childhood during the study period. Their effects on the development of autoimmunity or the progress of the disease process may be factors contributing to the decreased incidence rate.
Mikael Knip, professor
Phone: +358 50 448 7722
Anna Parviainen, MD
Reference: Decreased Incidence of Type 1 Diabetes in Young Finnish Children. Anna Parviainen, Anna But, Heli Siljander, Mikael Knip, the Finnish Pediatric Diabetes Register. Diabetes Care 2020 Sep; doi.org/10.2337/dc20-0604