Diabetes and IGT Prevalence in Islamshahr and Detection of Glucose Intolerance Screening and GTT: A Comparison

SUMMARY Due to the lack of information on diabetes prevalence and its precipitating factors and in view of the grave consequences of the disease, this study was carried out in 1993 to determine diabetes and IGT in Islamshahr, 30 km to the southwest of Tehran. Out of 244000 population in the district 2033 subjects over 30 years of age were selected hy stepwise randomized sampling. The subjects 835(41 %) were males and 1198 (59%) were females. In the first step fasting blood sugar and 2-hour glucose tolerance test was determined. In the second phase of the study which was carried out 9 months later, those with abnormal blood glucose test and some of the normal subjects underwent OGTT. The results showed 7.4% of the population (7. I% of men and 7 .6 % of women) to be diabetic. In 3.8% diabetes had been diagnosed but 3.6% were ignorant of their problem. Also 12.4% (8.9% males and 14.9% females) were IGT. Diabetes and IGT increased with age rising from 3.5 and 9.2% in the 30-39 year age group to 10.4 and 31.3 % in the 70-79 year group respectively. Fifty­two percent of the diabetics and 23 % of the IGT subjects had a positive history of diabetes. In the second stage 50% of the IGT group were still IGT. Twenty-five percent had entered the diabetic stage and 25% showed normal blood glucose levels. Of the newly diagnosed diabetics in the first stage 72 % remained so in the second stage while 24 % were IGT and 3 % had normal blood glucose. Comparison of blood sugar based on WHO and NDDG showed 14% of the normal, 59.8% of the IGT and 11.8% of the new! y diagnosed diabetics as well as 28. 3 % of the whole subjects did not fall in any category of NDDG criteria. This study, therefore, shows high diabetes and IGT in the region, increase of diabetes with age and positive family history, based on our findings, only 2-hour glucose tolerance test is suggested as the criteria for diabetes and IGT diagnosis.