High Incidence of IDDM Over 6 years in Edmonton, Alberta, Canada
Ellen L. Toth, MD
Kwok-Choy Lee, MD, PHD
Robert M. Couch, MD
Laurence F. Martin, MD
Objective to determine the incidence of IDDM among childern 0-14 years of age in Edmonton,
Alberta, between 1990 and 1995 by means of a population-based registry.
Research Design and Methods Children 15 years of age diagnosed with IDDM between
January 1990 and December 1995 were registered according to criteria of the World Health Organization
(WHO) Multinational Project for Childhood Diabetes. The primary source of case ascertainmemt
consisted of office records of pediatricians and endocrinologists. The secondary source consisted of inpatient from
the main city hospitals.
Results Between 1990 and 1995, 211 IDDM patients 15 years of age were detected by
the two sources. All but the 15 of them were European ancestry. The ascertainment-corrected incidence
rates of this ethnic group (constituting 77% of the population) for the 6 years were 38.6, 23.5, 23.3,
24.4, 22.0, and 24.3 per 100,000 respectively with case ascertainment rates of 75-95%. The age-adjusted
rate over the 6-year period was 25.7 per 100,000 with a case ascertainment rate of 84.3%. No sex
difference was observed. The highest incidence occured in the 10 to 14 year old group, and more cases were
detected between Jaunary and March than at other periods in the year.
Conclusions The incidence of IDDM among the European-derived population in Edmonton
between 1990 and 1995 is the highest rate over a 6 year period to be reported in North America,
comparable to that in Prince Edward Island, Canada, and to the highest rates in the world.