Diabetes is on the rise across the globe as reported in the most recent 8th edition of the IDF Diabetes Atlas 2017.(1)
According to the IDF statistics, presently every seven seconds someone is estimated to die from diabetes or its complications, with 50% of those deaths (4 million in total per year) occurring under the age of 60 years. (1) This is against the background of a global diabetes prevalence of 8.8% (95% confidence interval 7.2-11.3%) of the world population in 2017, standardized for the age group 20-79 years.
The prevalence is expected to further increase to 9.9% (95% CI 7.5-12.7%) by the year 2045. In total numbers, this reflects a population of 424.9 million (95% CI 346.4-545.4 million) people with diabetes worldwide in 2017 with an estimate of a 48% increase to 628.6 million people (95% CI 477.0-808.7 million) for the year 2045. Global umbers of diabetes prevalence have continuously risen from 151 million in 2000, when the IDF Diabetes Atlas first was launched, to 285 million in 2009 and to 382 million in 2013. Disturbingly in this context, some 50% of all individuals with diabetes are undiagnosed, especially in developing countries.(1)
The figures given in the IDF Atlas fit well with the estimates of an international consortium reporting worldwide trends in diabetes since 1980 based on a pooled analysis of 751 population-based studies with 4·4 million participants. (2) According to this group global age-standardised diabetes prevalence increased from 4.3% (95% CI 2.4-7.0) in 1980 to 9.0% (7.2-11.1) in 2014 in men, and from 5.0% (2.9-7.9) to 7.9% (6.4-9.7) in women.
Moreover, it was estimated that the number of adults with diabetes in the world had increased from 108 million in 1980 to 422 million in 2014 (28.5% due to the rise in prevalence, 39.7% due to population growth and ageing, and 31.8% due to interaction of these two factors). Besides the growth and aging of the world population in general, the global obesity epidemic has turned out to be a key factor for the rise of diabetes incidence together with the immense progress of multifactorial cardiovascular risk management and successful revascularisation therapy of people with diabetes also contributing to the expansion of the worldwide diabetes population. (1-6)
In addition to overt diabetes, the IDF Atlas estimates another352.1 million (95% CI 233.5 -577.3 million) people worldwide to have a pre-stage of diabetes, called Impaired Glucose Tolerance (IGT), a figure which is anticipated to rise to 531.6 million (95% CI 353.8-883.9 million) in 2045. (1)
In the latter group, the manifestation of overt diabetes could actually be prevented in most people by appropriate measures, along with most of the severe complications of diabetes at the heart, the brain, the eyes, the kidneys, and the feet.
On a global scale, diabetes hits particularly “middle-aged” people between 40 to 59 years of age which causes serious economic and social implications. Furthermore, diabetes affects especially low and middle income countries, as 77% of all people with diabetes worldwide live in those countries. Table 1 (modified from the IDF Diabetes Atlas 2017) summarizes the growing burden of the global diabetes epidemic. (1-4)
The Growing Burden of the Diabetes Epidemic
Diabetes more or less equally affects both sexes with men having a small edge over women at younger age groups and women surpassing men at higher age groups. (1,2)
Depending on age groups, global diabetes prevalence is about 5% for the age group 35-39 years, 10% for the age group 45-49 years, 15% for the age group 55-59 years, and close to 20% starting at age group 65-69 years. (1) Diabetes prevalence numbers are largely determined by people with type2 diabetes who comprise about 90% of the total population. These individuals are characterized by various degrees of relative insulin deficiency in conjunction with a wide spectrum of insulin resistance.
About five percent of the total diabetes population represents monogenic forms of diabetes, such as various subtypes of MODY (maturity-onset diabetes of the young) and other rare genetic conditions, another five percent encompass sub-forms of immune-mediated type 1 diabetes with a pronounced, if not absolute insulin deficit in the long run.(1) Reflecting the enormous therapeutic progress in the last thirty years, many people afflicted with type 1 diabetes today are able to live for almost a normal life span, although the disease usually starts at a young age, i.e.in children and adolescents. For the age group 0-19 years, the IDF Diabetes Atlas 2017 provides a global number of 1,106,500 people with type 1 diabetes with an annual incidence of 132,600 newly diagnosed cases. (1)
Mortality, though decreasing in the last thirty years, has remained at least twofold increased both in adult type 1 and type 2 diabetes compared with the general population. (3-6) Excessive death rates not only relate to cardiovascular causes that will be further discussed in other chapters of this programme, but also to non-cardiovascular causes such as cancer, renal disease, liver disease, pneumonia, septicaemia and other infections. (3-6) In contemporary global cohorts of type 2 diabetes, e.g. as studied in the TECOS trial, more than 50% of all deaths is due to cardiovascular causes with sudden death being the most common cause, followed by combined death from myocardial infarction or stroke, and death from heart failure. (7) Particularly high death rates are unfortunately still reported for young onset type1 diabetes (age group 0-10 years). They showed hazard ratios of 4.11 (95% CI 3.24-5.22) for all-cause mortality, 7.38 (3.65-14.94) for cardiovascular mortality, and 3.96 (3.6-5.11) for non-cardiovascular mortality in a recent assessment based on the National Diabetes Register in Sweden. (6)
The content of this article reflects the personal opinion of the author/s and is not necessarily the official position of the European Society of Cardiology