Incidence of insulin-dependent diabetes mellitus in age groups over 30 years in Denmark

Diabet Med. Aug-Sep 1994;11(7):650-5. doi: 10.1111/j.1464-5491.1994.tb00327.x.


The incidence of IDDM in the age group over 30 years was estimated in a historical prospective study, using clinical and biochemical measurements at onset as criteria for classification. The study population, nearly one million, represents 20% of the Danish population. The degree of ascertainment was > 99%. One thousand two hundred and forty patients were treated with insulin during the study period (1973-77). Based on the clinical and biochemical variables, the patients were classified into three groups: insulin-dependent diabetes mellitus (IDDM) accounted for 16.2%, insulin-treated diabetes mellitus for 54.1% and short-term treated diabetes mellitus for 29.6% of the total insulin-treated group. The incidence of IDDM in the age group over 30 years at onset was 8.2 100,000(-1) year-1. The cumulative incidence rate (0-90 years) was 1.5-1.6 per cent. The present study indicates that IDDM may develop at any age. Thus the life-time risk of developing IDDM is higher than hitherto expected.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Autoantibodies / blood
  • Cohort Studies
  • Denmark / epidemiology
  • Diabetes Mellitus, Type 1 / classification
  • Diabetes Mellitus, Type 1 / drug therapy
  • Diabetes Mellitus, Type 1 / epidemiology*
  • Female
  • HLA-DR Antigens / blood
  • Humans
  • Incidence
  • Insulin / therapeutic use
  • Islets of Langerhans / immunology
  • Male
  • Middle Aged


  • Autoantibodies
  • HLA-DR Antigens
  • Insulin
  • islet cell antibody