The epidemiology of insulin-dependent diabetes mellitus (IDDM): report from Thailand.

The epidemiology of diabetes mellitus in Thai children aged 0-15 years was studied in 1985 and compared with a previous study done in 1984. Four hundred and seventy-six questionnaires were sent each year to hospitals in Thailand. In 1984, thirty-six cases of newly diagnosed diabetes mellitus were found of which 35 were IDDM and one was NIDDM. In 1985, twenty-seven cases of new IDDM were found, no case of NIDDM was reported. Two cases of MRD were reported from the Northeastern and Southern part of Thailand. The incidence of IDDM in the whole kingdom of Thailand was 0.19/100,000/year in 1984 and 0.14/100,000/year in 1985. The male to female ratio was 1:1.5 in 1984 and 1:2 in 1985. The peak age at diagnosis showed the main peak at 14 years old in boys. The peak age of girls preceded boys by 1-2 years in 1984 and 1985. Similar findings in 1984 and 1985 were the onset of symptoms showing a seasonal variation with highest frequency in winter with a slight change of increased incidence in the rainy season of 1985. There was an increased incidence of IDDM in families with lower educational and socioeconomic levels. The newly diagnosed IDDM with DKA was 16.2, and 19.5 per cent in 1984 and 1985. The incidence of IDDM in Thai children, aged 0-15 years seems to be the lowest compared to other countries previously described which might be due to some genetic and environmental including diet, micronutrient, eating habits and life-style which might play a role in the difference.