|Prevalence estimates of
Impaired glucose tolerance, 2007
of Impaired glucose tolerance, 2025
The main aim of this section is to estimate the prevalence for impaired glucose tolerance (IGT) for each country for the years 2007 and 2025. Data are provided for 215 countries and territories, which have been allocated mostly on a geographical basis into one of the seven IDF regions: Africa (AFR), Eastern Mediterranean and Middle East (EMME), Europe (EUR), North America (NA), South and Central America (SACA), South-East Asia (SEA), and the Western Pacific (WP).
The prevalence of IGT has been calculated in two ways:
1. The age and sex structure of each specific country has been used to provide an accurate estimate of the percentage of adults affected within each country.
2. The age and sex structure of the world population has been used to provide a prevalence estimate for each country that can readily be compared to other countries.
Only adults aged from 20 to 79 years of age are considered because the majority of all people who have IGT are adults.
It should be noted that column numbers in the Tables may not always exactly be the sum of the components because of rounding effects.
It is estimated that approximately 309 million, or 7.5% in the age group 20 – 79, have IGT in 2007, of which more than 80% live in developing countries. By 2025 the number of people with IGT is projected to increase to 418 million, or 8.1%, in the adult population (see Tables 3a-c on regional estimates for IGT).
The Western Pacific Region is estimated to have the greatest number of people with IGT in 2007 with some 112 million, although the European Region has the highest prevalence rate with 9.1% of the adult population affected by IGT (see Figure 1). By 2025, absolute numbers of persons with IGT are generally likely to increase by 30-70% in many regions, with the greatest increases in Africa, and the Eastern Mediterranean and Middle East (see Figure 2).
Figure 2 | Number of people with impaired glucose tolerance (20-79 age group) by region, 2007 and 2025
The prevalence of IGT is generally similar to that of diabetes, but somewhat higher for the African and Western Pacific Regions, but slightly lower than of diabetes in the North American Region (see Figure 3).
Figure 3 | Prevalence of diabetes and impaired glucose tolerance* (20-79 age group) by region, 2007 and 2025
Figure 4 highlights the large increases in absolute numbers of both diabetes and IGT over the 18-year period.
Figure 4 | Number of people with diabetes and impaired glucose tolerance (20-79 age group) by region, 2007 and 2025
As with diabetes, the 40-59 year age group is expected to have the greatest number of persons with IGT for 2007 with some 122 million, and this will remain true in 2025 with 164 million as shown in Figure 5. It is also of note that one-third of all those who will have IGT for 2007 are in the 20-39 year age group.
Figure 5 | Number of people with impaired glucose tolerance by age group, 2007 and 2025
Figure 6 | Top 10: Prevalence of impaired glucose tolerance* (20-79 age group) in 2007 (with 2025 prevalence)