incidence of IDDM

Last edited 11/2018 and last reviewed 05/2021

Around 10% of the people with diabetes have type 1 diabetes (T1D) (1).

It may occur at any age, however it is the most common chronic disease seen in children (2).

  • peak age of presentation is between 5-7 years of age and at or near puberty
  • it is slightly more common in boys and men

A variation in incidence has been reported with season and birth month.

  • more cases are diagnosed in autumn and winter
  • spring births were associated with increased likelihood T1D (2)

A wide variation in the incidence and prevalence of T1D can be observed globally.

  • it is more common in Finland (>60 cases per 100 000 people each year) and Sardinia (around 40 cases per 100 000 people each year)
  • uncommon in China, India, and Venezuela (around 0·1 cases per 100 000 people each year).
  • furthermore, a wide variation in incidence is seen in neighbouring areas in Europe and North America e.g. - incidence in Estonia is less than one-third of the incidence in Finland (the two countries are separated by less than 120km) (2).

An increase in the incidence of T1D is reported worldwide for several decades.

  • annual increases in incidence in Finland, Germany, and Norway is 2·4%, 2·6%, and 3·3%, respectively
  • the rise in incidence has fluctuated in other countries. In Sweden, the incidence rate has plateaued
  • the increase in incidence is not seen equally across all age groups
    • in Europe, the most substantial increases have been noted in children younger than 5 years of age
  • the global incidence is expected to double over the next decade if the incidence rates continue to increase at the same rate (2)

IDDM accounts for:

  • 25% of all new cases of primary diabetes
  • 50% of all patients taking insulin

Diabetes UK state (1):

  • there are about 35,000 children and young people with diabetes, under the age of 19 out of which 96% have Type 1 diabetes
  • prevalence of Type 1 diabetes in children and young people under the age of 19 in the UK is one per 430 – 530
  • the incidence of Type 1 diabetes in children under the age of 14 is 24.5/100,000
  • the peak age for diagnosis is between 10 and 14 years of age (1)