Relationship between Mortality Status of Children with IDDM and Regional Characteristics

The present study evaluated how regional characteristics were related to the mortality status of children with IDDM. Of 1217 subjects diagnosed between 1965~1979 with age of onset less than 18 years, 83 patients had died as of 1-1-1990, and the 78 whose place of residence was known were matched with 78 randomly selected living controls by sex and year of diagnosis. Urban-rural indices and income indices were compared in patients (cases) and controls, and the date were analyzed by the Wilcoxon 2-sample test. The results showed that population density and income ratio to national and prefectural means were higher in the controls than in the cases (p<0.01). The proportion of agricultural households, on the other hand, was lower (p<0.01). A similar pattern was seen in both sexes. The effect was most evident among patients diagnosed in 1965-69. Mortality appeared to be highest in rural and low SES areas. Further study is necessary to clarify possible different environmental factors in urban and rural areas and high and low SES areas which might affect prognosis of children with IDDM.