Worldwide increase in incidence of Type I diabetes - the analysis of the data on published incidence trends

Abstract

The aetiology and natural history of Type I (insulindependent) diabetes mellitus are still not known but both genetics and environmental factors contribute to the development of the disease [1±3]. Although HLA genetics have a major role in the aetiology of Type I diabetes, other genes also contribute to the genetic effect, but the mode of inheritance of the disease is not clear [4]. The genetic effect contributes 70±75 % of the susceptibility to Type I diabetes [5,6]. Environmental factors possibly initiate or trigger the process which leads to the destruction of the beta cells and the onset of diabetes [3,7,8].In the late 1970 s epidemiological reports of diabetic children for the first time showed a wide geographical variation in the incidence of Type I diabetes. During the 1960 s to the early 1980 s the data on incidence of Type I diabetes were available for a few populations only, mostly from regions with a high or intermediate risk for this disease. A large number of registries had been established since the mid 1980 s worldwide. The lack of standardized data made it difficult to determine the true magnitude of the worldwide variation in incidence or time trends [9]. The Di- Diabetologia (1999) Abstract Aims/hypothesis. Several reports on the incidence of Type I (insulin-dependent) diabetes mellitus have suggested that the incidence is increasing. The aim of this study was to find out whether the incidence is increasing globally or restricted to a selected populations only and to estimate the magnitude of the change in incidence. Methods. During 1960 to 1996 37 studies in 27 countries were carried out. To fulfil the inclusion criteria the study periods ranged from 8±32 years. The temporal trend was fitted by linear regression, with the logarithm of the age-standardized incidence as the dependent variable and the calendar year as the independent variable. Then, the regression coefficient (´100 %) is approximately the average relative increase in incidence per year (as percentage). Results. Results from the pooled data from all 37 populations showed that the overall increase in incidence was 3.0 % per year (95 % CI 2.6; 3.3, p = 0.0001). The statistically significant increase was found in 24 of 37 populations including all high incidence ( > 14.6 per 100 000 a year) populations. The relative increase was, however, steeper in the populations with a lower incidence. The correlation between logarithm of the incidence and the increase in incidence was r = ±0.56, p = 0.0004. Conclusion/interpretation. The incidence of Type I diabetes is increasing worldwide both in low and high incidence populations. By the year 2010 the incidence will be 50 per 100 000 a year in Finland and also in many other populations it will exceed 30 per 100 000 a year. [Diabetologia (1999

Atopic eczema in early childhood could be protective against Type 1 diabetes

“…Additionally, there is substantial evidence from clinical and experimental data that Th1/Th2 balance is important to the development of atopic and autoimmune diseases [2,26,27,28,29,30]. On the other hand, both Type 1 diabetes and atopic diseases have been rising during the last decades [31,32,33,34], according to the 'hygiene hypothesis' possibly due to a decrease of infectious diseases in industrialized countries [35,36]. This apparent paradox that Type 1 diabetes and atopic disorders share common epidemiological characteristics but represent opposite deviations of the immune response remains to be resolved [36].…”

Prospective incidence study of diabetes mellitus in New Zealand children aged 0 to 14 years

“…To allow direct comparison with international registries, incidence rates were calculated as the incidence per calendar year per 100,000 individuals at risk, according to protocols of the DIAMOND study [1].…”

“…This method is the world population standard and has been used by the DERI study group [11] and the WHO DIAMOND project [1].…”

“…Reports from many populations indicate that the incidence of both type 1 and type 2 diabetes is increasing in the under-15 age group [1,2]. While increasing rates of obesity and sedentary lifestyles appear to account for the increase in type 2 diabetes, relatively little is known about why type 1 diabetes is increasing.…”

Vaccination and autoimmune diseases: is prevention of adverse health effects on the horizon?

“…These autoimmune disorders (rheumatic, endocrinological, and gastrointestinal diseases) are increased significantly over the last 30 years and affect more than 5% of the individuals worldwide at the age of vaccination programs, which is quite different compared to the spontaneous autoimmune disease incidence [6][7][8][9]. These observations raise the problem whether vaccination should be recommended or avoided in autoimmune risk patients [10].…”