Epidemiology of IDDM in southern Chinese children in Hong Kong.

OBJECTIVE

To provide reliable data on the incidence of IDDM in southern Chinese children in Hong Kong.

RESEARCH DESIGN AND METHODS

A registry was established in 1991 to collect childhood IDDM cases retrospectively and prospectively from four districts in Hong Kong. The study included all newly diagnosed cases of IDDM with onset < 15 yr of age from 1 January 1986 to 31 December 1990. Primary ascertainment was based on review of medical records at a regional hospital serving the four districts. An independent school survey validated registry data.

RESULTS

The completeness of ascertainment was 93.8%. The age-standardized incidence of IDDM was 2.0/100,000/yr with the 95% confidence interval of 1.2-3.0/100,000/yr for children < 15 yr of age during the study period. The incidence rates/100,000/yr for the three age-groups were: < or = 4 yr, 0.8; 5-9 yr, 2.2; 10-14 yr, 2.8. The incidence for males was 1.5/100,000/yr (95% confidence interval 0.7-2.9/100,000/yr) and for females, 2.4/100,000/yr (95% confidence interval 1.3-4.0/100,000/yr).

CONCLUSIONS

This study documents a very low incidence rate of childhood IDDM in southern Chinese in Hong Kong.