Global burden of diabetes mellitus
The worldwide incident cases of diabetes mellitus increased by 102.9%, from 11,303×103 (95% UI, 10,582×103–12,102×103) in 1990 to 22,936×103 (95% UI, 21,083×103–25,041×103) in 2017. The global ASIR increased from 234/100,000 persons (95% UI, 219–249) in 1990 to 285/100,000 persons (95% UI, 262–310) in 2017 (EAPC=0.87, 95% CI: 0.79–0.96) (Table 1).
The number of diabetes mellitus incident cases increased in both sexes from 1990 to 2017. The incident cases in males increased by 103.3%, from 5,791×103 (95% UI, 5,403×103–6,214×103) in 1990 to 11,770×103 (95% UI, 10,839×103–12,850×103) in 2017, and the ASIR increased significantly with an EAPC of 0.89 (95% CI, from 0.81 to 0.99), rising from 240/100,000 persons (95% UI, 225–256) in 1990 to 295/100,000 persons (95% UI, 272–321) in 2017 (Table 1), while that in females increased by 102.6%, from 5,512×103 (95% UI, 5,162×103–5,886×103) in 1990 to 11,166 ×103 (95% UI, 10,244×103–12,217×103) in 2017 and the ASIR increased from 227/100,000 persons (95% UI, 213–243) in 1990 to 274/100,000 persons (95% UI, 252–399) in 2017 and the ASIR increased by annually an average of 0.85 (0.77–0.94) (Table 1). The ASIR in male incident cases and ASIR was higher than that in female in 1990 and 2017 (Table 1).
At the regional level, the incidence of diabetes mellitus increased across the five SDI regions (Fig. 2). The increase in ASIR was largest in high-SDI regions (EAPC=1.05, 95% CI:0.92–1.17) and smallest in low-SDI regions (EAPC=0.79, 95% CI:0.71–0.88) (Table 1). At the geographical level, the incident cases of diabetes mellitus increased from 1990 to 2017 in the 21 geographical regions (Table 1), with the increase being largest in western Sub-Saharan Africa (203.6%), and lowest Eastern Europe (14.0%). The incidence of diabetes mellitus increased from 1990 to 2017 in the 19 geographical regions (Fig. 3), The largest increase in ASIR was found in North America high-income (EAPC=1.98, 95% CI:1.64–2.31), while the largest decrease was found in tropical Latin America (EAPC= -0.30, 95% CI: from -0.40 to -0.19) (Table 1).
At the national level, the incident cases of diabetes mellitus increased the most in the United Arab Emirates (964.1%) and decreased the most in Bulgaria (-0.7%) (Fig.1B, Table S4). In addition, as for the absolute number, the largest number of diabetics in 2017, were in India (3,639,083×103cases), followed by China (3,338,131×103cases) and the USA (1,388,743×103 cases) (Table S4). The ASIR of diabetes mellitus varied considerably across the world in 2017, being highest in Kiribati (970 /100,000 persons), followed by Fiji and American Samoa (these countries are not marked on the map in the figure), and lowest in Colombia (187/100,000 persons), followed Japan and China (Fig. 1A, Table S4). The increase in ASIR was largest in Mauritius (EAPC=2.56, 95% CI:2.32–2.81), followed by Sri Lanka and the USA and the decrease in ASIR was largest in Greenland (EAPC=-1.32, 95% CI: from-1.38 to -1.26) followed by Ethiopia and Singapore from 1990 to 2017 (Fig. 1C)
Examining the relationship between all age groups and incidence showed that the incidence of T2DM increased from the 0-1 age group to the 5-9 age group, peaked in the 55-59 age group, after which it decreased slightly and increased in 75-79 age group and then decreased in both sexesin 1990 and 2017 (Fig. 4).
Besides, our study reported the prevalent cases and prevalence of diabetes mellitus of geographical regions. The number of diabetes mellitus patients increased in different degrees in 21 geographical regions and the prevalence of diabetes mellitus increased in 19 geographical regions (except Australasia and Tropical Latin America) (Table S3).
Type 1 diabetes
T1DM accounted for nearly 1.8% (n=400×103) of the total number of diabetes mellitus incident cases in 2017, while the proportion exceeded 5.0% in Greenland. At the global level, the number of annual incident cases was rising with 291×103 (95% UI, 263×103–323×103) in 1990 and 400×103 (95% UI, 362×103–442×103) in 2017 (Table S1). The global ASIR of T1DM displayed an increasing trend with an EAPC of 0.34 (95% CI: 0.30–0.39) from 1990 to 2017 (Table S1).
The absolute incident case numbers in males was observed with 160×103 (95% UI, 145×103–177×103) in 1990 and 211×103 (95% UI, 200×103–244×103) in 2017 (The number of cases has increased in 1990-2017 except 1994, Fig.S3A), while in females from 131×103 (95% UI, 118×103–145×103) to 179 (95% UI, 162×103–198×103) (Table S1). The ASIR of T1DM increased from 1990 to 2017 and the ASIR increased by annually an average of 0.34 (0.30–0.39) in males and females (Table S1).
At the regional level, the incident cases of T1DM increased across the five SDI regions from 1990 to 2017 (Fig. S4A). The ASIR of T1DM increased across four SDI regions from 1990 to 2017 among the largest increase in high SDI (Fig. S5A), while the ASIR was stable in low-SDI regions (EAPC=0.00, 95% CI: -0.03–0.02) (Table S1). At the geographical level, the number of T1DM incidence cases increased in 18 geographical regions (Fig.S6A), with the increase being highest in western Sub-Saharan Africa (129.6%), the lowest in Asia Pacific high-income (-21.6%). The number of T1DM cases decreased in three regions: Asia-Pacific high-income, central Europe (-2.1%), and East Asia (-0.2%). The largest increase in ASIR was observed in Western Europe (EAPC=1.20, 95% CI:1.04–1.36), followed by Australasia and central Europe (Table S1, Fig. 7A). The largest decrease in ASIR was found in tropical Latin America (EAPC= -0.19, 95% CI: -0.49–0.11) (Fig. 5, Table S1, Fig.7A).
At the national level, the largest increase in the incident cases of T1DM was observed in Qatar (493.5%) followed by the United Arab Emirates (382.0%) and Afghanistan (257.6%) (Fig. S1B). Meanwhile, the largest decrease was found in Georgia (-31.9%), followed by Bosnia and Herzegovina (-26.6%) (Fig. S1B, Table S4). The ASIR of T1DM was highest in Norway (20/100,000 persons), followed by Canada and Uruguay and lowest in Vietnam (2/100,000 persons) in 2017 (Fig. 1A, Table S4). The ASIR in the country with the highest rate (Norway) was 10 times higher than the lowest rate (Vietnam). The largest increase in ASIR of T1DM was observed in France (EAPC=2.11, 95% CI:1.93–2.29), and the largest decrease in ASIR was found in Finland (EAPC= -0.72, 95% CI: from -0.44 to -1.00) (Fig. S1C, Table S4).
Relationship between all age groups and incidence revealed that the incidence of T1DM increased from the 0-1 age group to the 5-9 age group, peaked in the 5-9 age group, and decreased to the lowest values in the 60-64 age group, after which it slightly increased in both sexes in 1990 and 2017 (Fig. S8A).
The number of T1DM patients increased in different degrees in 21 geographical regions and the prevalence of T1DM increased in 19 geographical regions (except South Asia and Tropical Latin America) (Table S3).
Type 2 diabetes
T2DM accounted for 98.3% (22,535×103) of the total number of diabetes mellitus incident cases in 2017. The absolute number of T2DM incident cases globally increased by 104.6%, from 11,013×103(10,283×103–11,811×103) in 1990 to 22,535×103(20,694×103–24,627×103) in 2017 (Table S1). The global ASIR of T2DM displayed an increasing trend with 228 /100,000 persons (95% UI, 214–244) in 1990 and 279/100,000 person (95% UI, 257–304) in 2017, with an EAPC of 0.89 (95%CI:0.80–0.97) (Table S1).
The absolute incident case numbers in males were showed with 5,631×103 (95% UI, 5247×103–6,055×103) in 1990 and 11,549(95% UI, 10,615×103–12,626×103) in 2017(The number of cases has increased in 1990-2017 except 1994, Fig. S3B), while in females from 5,382×103 (95% UI, 5,028×103–5,757×103) to 10,987×103 (95% UI, 10,067×103–12,037×103) (Table S1). The ASIR of T2DM increased in 1990-2017 and the ASIR increased by annually an average of 0.91(0.82–1.00) in males and 0.86(0.78–0.95) in females (Table S1).
At the regional level, T2DM cases increased across all five SDI regions, and incident cases of T2DM from 1990 to 2017 was highest among countries in the middle-SDI region (Fig. S4B). The increase in ASIR of T2DM was largest in high-SDI regions (EAPC=1.06, 95% CI:0.93–1.19), while the decrease was largest in low-SDI regions in 1990-2017 (EAPC=0.81, 95% CI: 0.72–0.90) (Table S2, Fig. S5B). At the regional level, the incident cases and ASIR of T2DM increased across the five SDI regions from 1990 to 2017 (Fig. S4, Fig. S5B).
At the geographical level, the number of T2DM cases increased in all 21 regions (Fig. S6B), with the highest increase observed in western Sub-Saharan Africa (207.4%), followed by North Africa and the Middle East (199.3%), and the smallest increase was found in Eastern Europe (14.3%). The increase in ASIR was largest in North America high-income (EAPC=2.07, 95% CI:1.72–2.42), followed by southern and western Sub-Saharan Africa and the largest decrease in ASIR was found in tropical Latin America (EAPC= -0.30, 95% CI: -0.40–-0.20) (Fig. 5, Table S1, Fig. S7A).
In the 194 countries in 2017, 36% of the incident cases of T2DM occurred in India, China, and the USA, while 10% of them occurred in Indonesia, Mexico, and Pakistan. The largest increase the incident cases of T2DM was found in the United Arab Emirates (975.8%) and the largest decrease was found in Bulgaria (-0.4%) (Table S4, Fig. S2B). The ASIR of T2DM was highest in Kiribati (968/100,000 persons), followed by Fiji and American Samoa. and lowest in Japan (177/100,000 persons) in 2017 (Fig.1A, Table S4). The ASIR in the country with the highest rate (Kiribati) was nearly 6 times higher than that in the country with the lowest rate. The largest increase in ASIR was in Mauritius (EAPC=2.57, 95%CI:2.33–2.82), followed by the USA (EAPC=2.38, 95% CI:1.97–2.78), and the largest decrease was in Greenland (EAPC= -1.41, 95% CI: from -1.47 to -1.35) (Table S4, Fig. S2C).
The study showed that the incidence of T2DM increased from the 10-age group to the 55-59 age group, peaked in the 55-59 age group, after which it decreased slightly in both sexes (Fig. 5B) in 1990 and 2017.
The number of T2DM patients increased in different degrees in 21 geographical regions and the prevalence of T2DM increased in 19 geographical regions (except Australasia and Tropical Latin America) (Table S3).
As shown in Fig. 6, a significant association was detected between EAPC and the HDI in 2017. The HDI in 2017 can serve as a surrogate for the level and availability of health care in each country, and a significant negative correlation was detected between EAPC and HDI (ρ= -0.21, p=0.006) among which EAPC was positively correlated with HDI (ρ= 0.59, p<0.0001) in type 1 diabetes, and was negatively correlated with HDI (ρ= -0.23, p=0.002) in type 2 diabetes. As HDI increased, countries experienced a more-steady decrease in the ASIR of diabetes mellitus from 1990 to 2017. Besides, the study found that the ASIR of T1DM differed with latitude and the farther away from the equator, the higher the ASIR in 2017 (ρ= 0.61, p<0.0001) (Fig. S4).