GLOBAL ESTIMATES FOR PREVALENCE OF DIABETES-MELLITUS AND IMPAIRED GLUCOSE-TOLERANCE IN ADULTS

OBJECTIVE - To assemble standardized estimates of abnormal glucose tolerance in adults in diverse communities worldwide and provide guidelines for the derivation of comparable estimates in future epidemiological studies. RESEARCH DESIGN AND METHODS - The project was limited to population-based investigations that had used current WHO criteria for diagnosis and classification of abnormal glucose tolerance. Raw data were obtained by WHO from surveys conducted during 1976-1991 of over 150,000 persons from 75 communities in 32 countries. Data within the truncated age range of 30-64 yr were adjusted to the standard world population of Segi. Age-specific prevalences also are reported for selected populations. RESULTS - Within the chosen age range, diabetes was absent or rare (<3%) in some traditional communities in developing countries. In European populations, age-standardized prevalence varied from 3 to 10%. Some Arab, migrant Asian Indian, Chinese, and Hispanic American populations were at higher risk with prevalences of 14-20%. The highest prevalences were-found in the Nauruans (41%) and the Pima/Papago Indians-(50%). Age-standardized prevalence of IGT was low (<3%) in some Chinese, traditional American indian, and Pacific island populations. Moderate (3-10%) or high (11-20%) prevalences of IGT were observed in many populations worldwide. The highest estimates for prevalence of IGT were seen in female Muslim Asian Indians in Tanzania (32%) and in urban male Micronesians in Kiribati (28%). Prevalence of diabetes rose with age in all populations in which age-specific data were examined. This trend was most pronounced in those at moderate to high risk. The ratio of prevalence of diabetes m men versus women varied markedly between populations with little discernable trend, although IGT was generally more common in women. In most communities, at least 20% of diabetes cases were unknown before the survey, and in many communities, >50% were previously undiagnosed. In both Chinese and Indian migrant populations, relative prevalence was high when compared with indigenous communities. CONCLUSIONS - Diabetes in adults is now a global health problem, and populations of developing countries, minority groups, and disadvantaged communities in industrialized countries now face the greatest risk.