The incidence of type 1 diabetes in young Czech children stopped rising

Type 1 diabetes in North East England and North Cumbria: patterns and time trends in 0-14-year-olds from 2012 to 2020

Introduction

It is important to understand patterns in the epidemiology of type 1 diabetes because they may provide insight into its etiology. We examined the incidence of type 1 diabetes in children aged 0-14 years, and patient demographics and clinical parameters at presentation, over the period 2012-2020 using the North East and North Cumbria Young Persons diabetes register.

Methods

Patients up to the age of 14 years with type 1 diabetes, and their families- managed in a total of 18 young persons diabetes clinics-were approached in person at the time of clinic appointments or in the days following diagnosis and they consented to their data being included in the register. Data were submitted regionally to a central unit. Descriptive statistics including crude and age-specific incidence rates were calculated. Temporal trends were analyzed using Joinpoint regression. Comparisons in incidence rates were made between age, sex and areas of higher and lower affluence as measured by the Index of Multiple Deprivation (IMD).

Results

A total of 943 cases were recorded between January 2012 and December 2020. Median age at diagnosis was 8.8 years (Q1: 5.3, Q3: 11.7). There were more males than females (54% male). The median HbA1c at diagnosis was 100 mmoL/L (IQR: 39) and over one third (35%) were in ketoacidosis (pH < 7.3). Crude incidence decreased from 25.5 (95% confidence interval [CI] 20.9, 29.9) in 2012 to 16.6 (95% CI: 13.0, 20.2) per 100,000 in 2020 (5.1% per annum, 95% CI 1.1, 8.8%). During the period of the study there was no evidence of any trends in median age, HbA1c, BMI or birthweight (p = 0.18, 0.80, 0.69, 0.32) at diagnosis. Higher rates were observed in males aged 10-14 years, but similar rates were found for both sexes aged 0-9 years and there was no difference between areas of higher or lower deprivation (p = 0.22).

Conclusion

The incidence of diabetes in the young may be falling in the North East of England and North Cumbria. The reasons are unclear as there were no associations identified between levels of deprivation or anthropometric measurements. Potential mechanisms include alterations in socioeconomic background or growth pattern. Further research is needed to understand the reasons behind this finding.

Type 1 diabetes incidence increased during the COVID-19 pandemic years 2020-2021 in Czechia: Results from a large population-based pediatric register

BACKGROUND

To explore type 1 diabetes incidence patterns during the pandemic years 2020 and 2021 in Czechia, to compare them to the trends from the previous decade, and to test its association with indicators of containment measures and of pandemic severity (school closing and the all-cause excess mortality).

METHODS

The Czech Childhood Diabetes Register is a population-based incidence register recording patients age 0-14.99 years at diabetes onset. Type 1 diabetes incidence in the pandemic period (April 2020-end of observation Dec 2021) was compared by Poisson regression models to the incidence patterns over the past decade 2010-2019.

RESULTS

During the pandemic years 2020-2021, 956 children 0-14.99 years old manifested with type 1 diabetes in Czechia. The observed incidence (27.2/100,000/year) was significantly higher than what was expected from the trends over 2010-2019 (incidence rate ratio, IRR = 1.16, 95%CI 1.06-1.28, p = 0.0022). The incidence had a trough during the first lockdown (March-May 2020), then it rose above expected values with no usual summer decrease. The assessed pandemic indicators (school closing and all-cause excess mortality) were not associated with the incidence levels.

CONCLUSIONS

The COVID-19 pandemic was associated with a notable upward inflection of the type 1 diabetes incidence curve; the early months of the first lockdown were however hallmarked by a significant dip in new diabetes diagnoses. Long-term observation will show whether the increased incidence originated only from accelerating an advanced preclinical Stage 2 to overt diabetes, or whether the pandemic triggered new cases of islet autoimmunity.

Trends in incidence and prevalence of type 1 diabetes between 1999 and 2019 based on the Childhood Diabetes Registry of Saxony, Germany

OBJECTIVE

The Childhood Diabetes Registry of Saxony has been existing since 1999. The aim of this study was to investigate the incidence rates, cohort and point prevalence, and the trends of type 1 diabetes among children and adolescents based on the registry data over the past 21 years.

METHODS

A completeness check of the Childhood Diabetes Registry of Saxony for the observation period 2012-2019 was performed using the capture-recapture method. The age-standardized incidence rates per 100,000 person years (PY) were estimated for the observation period 1999-2019. Prevalence was estimated per 100,000 children and adolescents as the point prevalence of five consecutive years, and as a cohort prevalence for the birth cohorts, which result from the difference of age and year at diagnosis. Trend analyses were executed using join point regression.

RESULTS

A completeness of 98% (95% CI 89-100) was determined for the period from 2012 to 2019. The standardized incidence rate of type 1 diabetes among children and adolescents increased from 17.1 per 100,000 PY in 1999 to 24.7 per 100,000 PY in 2019. If this trend continues, the incidence rate will increase to 34.8 (95% CI 24.4-49.6) per 100,000 PY in 2030. The point prevalence of 5 consecutive years did not show a continuous trend over time. According to this method, the prevalence reached a plateau in the last segment (2013-2019). The calculation of cohort prevalence indicated a continuous increase from 2013 to 2019 with no significant statistical difference in terms of sex.

CONCLUSION

The point prevalence and the last incidence rates indicate that type 1 diabetes of children and adolescents is slowing down or has reached a plateau in Saxony. Nevertheless, the cohort prevalence predicts a steady increase. Future studies should continue investigating these trends in a longer observation period and consider including possible correlating environmental factors.

PRE-RETINOPATHY OF TYPE 1 DIABETES IN THE CONTEXT OF FUNCTIONAL, STRUCTURAL AND MICROCIRCULATORY CHANGES IN THE MACULAR AREA

AIM

The authors assessed the development of intraocular changes in type 1 diabetes (T1DM) from the onset of the disease leading to diabetic retinopathy (DR). The quote: &#8220;There must be an intermediate stage between the physiological intraocular finding and the diabetic retinopathy itself &#8220;, (prof. Jan Vav&#345;inec).

METHODS

A two-year study (2018 and 2019) was conducted at the Department of Ophthalmology of the Teaching Hospital Kralovske Vinohrady in Prague (Czech Republic). There were 54 patients aged 17-42 years, the detection of T1DM ranged between the 1st and 14th year of life, with a duration of 12-35 years. Individual patients were always examined simultaneously by three methods: CS (contrast sensitivity), SD-OCT (spectral domain optical coherence tomography) and OCT-A (optical coherence tomography-angiography). We examined 106 eyes once and in a comprehensive manner.

RESULTS

We have shown that there is an intermediate stage between the physiological finding on the retina and DR, so-called diabetic pre-retinopathy (DpR). Subsequent redistribution of the observed into two DpR subgroups was derived from the size of the FAZ, either with its smaller area or with a larger area determining the microvascularity of the central area of the retina. The results of both other methods were assigned to these values. For SD-OCT, the depth of the fovea (the difference between the central retinal thickness and the total average retinal thickness) was determined, which was affected by the increased the macular cubature. In all patients it was on average 10.3 &#956;m3. The retina in the central area was significantly strengthened compared to the healthy population at the level of significance p 0,001. We divided the actual DpR into an image: DpR1 in 26.5 % of eyes - condition with an average shallower fovea only by 21.5 &#956;m below the level of the surrounding retina and an average narrower FAZ: 0.165 mm2 and with a more significant decrease in CS; DpR2 in 40.5 % of eyes - condition with average deeper fovea by 42 &#956;m, i.e., more significantly and average larger FAZ: 0.325 mm2 with lower decrease of CS. At the same time, other changes in microvascularity were noted, such as disorders in the sense of non-perfusion in the central part of the retina of various degrees. This finding differed significantly from changes in already established (non-proliferative) NPDR in 36 % of eyes, when a significant decrease in CS with normal visual acuity was found 4/4 ETDRS. Statistical differences in CS between DpR1 and DpR2 and NPDR were determined - always p 0.001. The average depth of the fovea was NPDR: 29.5 &#956;m. NPDR had the largest average FAZ: 0.56 mm2. Also significant were the most significant changes in non-perfusion and especially the presence of microaneurysms.

CONCLUSIONS

These three non - invasive methods helped to monitor the dynamics of the development of ocular changes in T1DM of better quality than the determination of visual acuity and ophthalmoscopic examination. Increased retinal volume induced hypoxia of visual cells with subsequent dual autoregulatory mechanism conditioning two types of diabetic pre-retinopathy before the onset of DR.

Use of continuous glucose monitoring and its association with type 1 diabetes control in children over the first 3 years of reimbursement approval: Population data from the ČENDA registry

OBJECTIVE

Increased access to modern technologies is not always accompanied by a decrease in HbA1c. The aim of this study was to identify changes in the proportion of continuous glucose monitoring (CGM) users since 2017, when general reimbursement for CGM became effective in Czechia, and to test whether HbA1c is associated with the percentage of time spent on CGM.

RESEARCH DESIGN AND METHODS

All T1D children in the Czech national ČENDA registry (3197 children) were categorized according to their time spent on CGM and associations with age, sex, center size, and HbA1c were tested with calendar year as a stratification factor.

RESULTS

The proportion of children with any CGM use increased from 37.9% in 2017 to 50.3% in 2018 and 74.8% in 2019. Of the CGM users, 16%, 28%, and 41% of the children spent >70% of their time on CGM over the 3 years of the study period, with an overrepresentation of children in the <10 years age group versus the older age groups (p < 0.001). The proportion of CGM users differed among centers and was positively associated with a large center size (>100 patients) (p < 0.001). HbA1c was negatively associated with the time spent on CGM (p < 0.001).

CONCLUSIONS

A rapid increase in CGM use was reported over the 3 years after general reimbursement. HbA1c was associated with time spent on CGM, a continuing decrease was observed in the >70% category. Reimbursement for CGM likely contributes to the improvement of T1D control at the population level.

Five years of improving diabetes control in Czech children after the establishment of the population-based childhood diabetes register ČENDA

OBJECTIVES

The Czech National Childhood Diabetes Register (ČENDA) is a web-based nationwide database that collects treatment and outcome data in children and adolescents with diabetes. Here, we present data from the first 5 years of ČENDA (2013-2017).

METHODS

Data include characteristics of disease onset and annual summaries of key clinical care parameters from every patient treated by participating pediatric diabetes outpatient clinics.

RESULTS

The database contains data of 4361 children (aged 0-19 years) from 52 centers (85% of all Czech pediatric patients). Of these, 94% had type 1 diabetes (T1D), 4.5% had genetically proven monogenic or secondary, and 1.5% had type 2 diabetes. In children with T1D, median glycated hemoglobin (HbA1c) decreased throughout the observed period from 66.3 to 61.0 mmol/mol (P < .0001, 95% confidence interval [CI] for change -5.6 to -4 mmol/mol). Consequently, the proportion of children reaching the target therapeutic goal of 58.5 mmol/mol increased from 28% in 2013 to 40% in 2017. The proportion of children treated with insulin pumps (CSII) remained stable over the observed period (25%). In a subanalysis of 1602 patients (long-standing T1D diagnosed before 2011), the main predictors associated with lower HbA1c were treatment with CSII, male sex and care provided at a large diabetes center (>100 patients).

CONCLUSIONS

A significant continuous decrease in HbA1c was observed in Czech children over the past 5 years. As this improvement was not accompanied by appreciable changes in the mode of therapy, we assume that the establishment of our nationwide register has itself constituted a stimulus towards improvement in the care process.

Incidence and trend of type 1 diabetes and the underlying environmental determinants

A wealth of epidemiological studies concerning the distribution of type 1 diabetes (T1D) around the world have pointed to the appreciable variation in the incidence of T1D among disparate age groups, ethnicities, and geographical locations. On the whole, the incidence of childhood T1D has been on the rise, and a plausible inverse relationship between the initial incidence rate and the following annual increase in incidence has been raised. Countries that used to exhibit lower incidences tend to have steep annual increase whereas those with already-established high incidences are more likely to show a modest increase or even stabilization in T1D incidence. Environmental agents considered responsible for the current evolving pattern of T1D incidence will be detailed, mainly including the increasing prevalence of childhood obesity, viral infections in a chronic manner, maternal-child interaction such as breastfeeding, and latitude-ultraviolet B-vitamin D pathway. Certain rationale has been put forward in an attempt to explain the potential association between environmental agents and development of T1D. For instance, accelerator hypothesis regards insulin resistance as the promoter of earlier disease onset in obese children whereas the negative correlation of microbial infections in background populations with incidence of T1D represents the basic component of the hygiene hypothesis. Further investigations are still warranted to verify these theories across multiple ethnic groups and to identify additional contributors to the variation in T1D incidence.

Incidence of Type 1 Diabetes in Children Aged Below 18 Years during 2013-2015 in Northwest Turkey

Objective

To assess the incidence of type 1 diabetes mellitus (T1DM) in children under 18 years of age in the northwest region of Turkey during 2013-2015.

Methods

All newly diagnosed T1DM cases were recorded prospectively during 2013-2015. Total, as well as gender and age group specific (0-4, 5-9, 10-14 and 15-17 age) mean incidences per 100,000 per year were calculated.

Results

There were 1,773 patients diagnosed during 2013-2015 (588 cases in 2013, 592 cases in 2014, 593 cases in 2015). Of these, 862 (48.6%) were girls and 911 (51.4%) were boys. The mean age at diagnosis was 9.2±4.2 years and it was not significantly different between girls (9.0±4.1 years) and boys (9.4±4.4 years) (p=0.052). The crude mean incidence was 8.99/100.000 confidence interval (CI) (95% CI: 8.58-9.42). Although mean incidence was similar between boys [8.98/100.000 (CI: 8.40 to 9.58)] and girls [9.01/100.000 (CI: 8.42 to 9.63)], there was male predominance in all groups except for 5-9 year age group. The standardized mean incidence was 9.02/100.000 according to the World Health Organization standard population. The mean incidence for the 0-4, 5-9, 10-14 and 15-17 age groups was 6.13, 11.68, 11.7 and 5.04/100.000 respectively. The incidence of T1DM was similar over the course of three years (p=0.95). A significant increase in the proportion of cases diagnosed was observed in the autumn-winter seasons.

Conclusion

The northwest region of Turkey experienced an intermediate incidence of T1DM over the period of the study.

Epidemiology of type 1 diabetes in Polish children: A multicentre cohort study

BACKGROUND

The incidence of childhood type 1 diabetes (T1D) varies greatly between populations, and the estimates and/or predictions of the rates would aid in adequate planning of health care resources. The study's aim was to assess the incidence of T1D in the paediatric population of eastern and central Poland.

METHODS

In this cohort study covering the period from January 2010 to December 2014, data were collected for children and adolescents below 18 years of age with newly diagnosed T1D living in eastern and central Poland. A total of 2174 children were included in the analysis. The population estimates were from the Central Statistical Office of Poland.

RESULTS

Overall, the annual incidence of T1D increased from 12.84/100,000 in 2010 to 18.46/100,000 in 2014 with the incidence rate (IR) ratio of 1.5 (an increase in the IR by 12.7% per year over 5 years). The lowest increase in the IR by 7.1% per year was seen in 15 to 17-year-olds. In the urban population (age 0-17 years), the overall incidence rate was significantly higher than in subjects from rural communities (P < .02). The incidence of T1D in rural areas was significantly higher (p = .004) in voivodeships of higher population density. Such dependence was not observed in urban areas.

CONCLUSIONS

The incidence of T1D in children living in eastern and central Poland increased 1.5-fold over the 5-year observation period with the highest rise in 10 to 14-year-olds and significantly higher rates in urban children compared with their peers living in rural areas.

Increasing incidence of type 1 diabetes between 1986 and 2015 in Bauru, Brazil

AIMS

To assess temporal trends in the incidence of type 1 diabetes in Bauru, São Paulo State, Brazil from 1986 to 2015.

RESEARCH DESIGN AND METHODS

The yearly incidence of type 1 diabetes (per 100,000/yr) from 1986 to 2015 was determined in children ≤14yr of age, using individual case notification and the capture and recapture method.

RESULTS

During thirty years (1986-2015), 302 cases were diagnosed in our population. The overall incidence was of 12.8/100,000 (95% CI: 11.2-14.4), ranging from 2.8/100,000 in 1987 to 25.6/100,000 in 2013 with a 9.1-fold variation. It was non-significantly higher in girls [13.7 (95% CI: 11.4-16.1)] than in boys [12.0 (95% CI: 9.8-14.2)] (p=0.48) and significantly higher in the 5-9yr [14.6 (95% CI: 11.8-17.4)] and 10-14yr [15.8 (95% CI: 12.7-18.8)] age ranges compared to the 0-4yr [8.1 (95% CI: 6.0-10.2)] age range (p<0.001). The majority of diagnoses were made in colder months. The patterns of incidence were very high and high in 80.0% of the study-years.

CONCLUSIONS

The incidence of type1 diabetes in children ≤14yr has increased in Bauru, Brazil, in the last thirty years, in approximately 3.1% annually, with an absolute crude increase of 2.5-fold. These findings pose Brazil as a country with high incidence of type 1 diabetes. All Brazilian regions should be enrolled in future studies to determine the factors that contribute to the predisposition to type 1 diabetes in our population and to the steep rise in its incidence.

Incidence of childhood-onset type 1 diabetes in Biscay, Spain, 1990-2013

OBJECTIVE

To identify the incidence rate (IR) and epidemiologic trends of childhood type 1 diabetes mellitus (T1DM) in children aged 0 to 14-yr-old from 1990 to 2013, in the north of Spain (Biscay).

SUBJECTS AND METHODS

A prospective-retrospective study was performed. Capture-recapture method was used: primary cases were ascertained from hospital register and a secondary independent data source was obtained from diabetes associations and public health plan database. Age and sex-standardized incidence rates were calculated using direct method, assuming an equal distribution in each age/sex group. In order to identify and analyse trends the period studied was divided into two (1990-2001 and 2002-2013) 11-year periods. The 95% confidence interval (CI) was estimated assuming the Poisson distribution.

RESULTS

A total of 399 new cases were identified throughout the study. Mean age at diagnosis was 8.9 ± 3.7 yr. Completeness of ascertainment was 99.1%. Mean annual age-standardized IR was 10.7 (95% CI: 9.6-11.7). The mean incidence for the 0-4, 5-9 and 10-14 age groups was 5.1, 14.6 and 13.2 per 100,000 children/yr, respectively. The incidence rate trend in the whole group was not statistically significant. In the 10-14 age group we found a yearly average increase (2.5% [CI 95% 0.4-4.6]; P < 0.05) and analysing by sex, this statistically significant incidence trend was observed only in boys. We did not find a seasonal onset pattern.

CONCLUSIONS

The IR did not increase in this population during the period studied unlike the results in other Spanish regions and European Countries.

Increasing trends in the incidence and prevalence rates of type 1 diabetes among children and adolescents in the Netherlands

OBJECTIVE

To assess the trends in the incidence and prevalence rates of type 1 diabetes (T1D) among children and adolescents in the Netherlands.

METHODS

A population-based cohort study was conducted in the Dutch PHARMO record linkage system (1998-2011). All children and adolescents aged ≤19 yr with at least one insulin dispensing (as a proxy for T1D) were identified and the numbers of incident and prevalent cases (numerators) were calculated. Overall age-adjusted (0-19 yr) incidence and prevalence rates together with age- and sex-specific rates of T1D and their 95% confidence intervals (CI) were calculated using data from the Dutch Central Bureau of Statistics as denominator. Trends over time were assessed using Joinpoint regression software (National Cancer Institute, Bethesda, MD, USA).

RESULTS

In 2011, the overall age-adjusted incidence and prevalence rates of T1D were 25.2/100 000 (95% CI, 23.7-26.8) person-years (PY) and 174.4/100 000 (95% CI, 170.2-178.5) children, respectively. The average annual percentage change (AAPC) in the overall age-adjusted incidence and prevalence rate was 3.7% (95% CI, 1.8-5.7) and 3.8% (95% CI, 2.4-5.2), respectively. While during the study period the largest increases in the incidence and prevalence rates of T1D were observed for the oldest age groups (10-14 and 15-19 yr), a decreasing trend was detected for the 0- to 4-yr-old category (with AAPCs of -1.8 (95% CI, -9.9 to 7.1) and -6.9% (95% CI, -11.5 to -2.1) for incidence and prevalence, respectively).

CONCLUSION

Age-adjusted incidence (1999-2011) and prevalence rates (1998-2011) of T1D in Dutch children (aged 0-19 yr) continued to increase and a shift was observed to a later onset of the disease.

Type I diabetes in paediatric age in Apulia (Italy): Incidence and associations with outdoor air pollutants

AIM

This study aimed to explore Type 1 diabetes (T1D) incidence and possible relations with specific air pollutants in a large population of children, during a wide time period.

METHODS

T1D rates and trends were examined (2001-2013, GAM and Joinpoint Regression analysis) by data on the first hospitalization in all children (0-14 years) living in Apulia (Southern Italy, average yearly population aged 0-14 years in the examined period: 631,275 subjects), and linked with levels of PM10, NOx, CO and ozone.

RESULTS

A total of 1501 children were first discharged in the selected area with a diagnosis of T1D. Incidence decreased from 48.5 (95% CI 43.3; 54.0, 2001) to 16.9 per 100,000 (95% CI 13.7; 20.6, 2013), with differences according to age at onset (constant at 0-4 years, continuously decreasing at 5-9 years, decreasing until 2003 at 10-14 years), and with a positive relation with PM10--but not ozone, NOx and CO average air levels. The OR was 1.037 (1.002; 1.074) in the high tertile of PM10 concentrations, and mean incidence was higher with PM10 levels in the highest, than in the medium/reference tertile. Mean age at T1D onset was linked with yearly PM10 and ozone air levels.

CONCLUSIONS

On a wide period, a stable or decreased incidence of T1D was evident in children with early- or later onset of disease, respectively. PM10 exposure significantly affects the incidence of T1D, which might be considered, at least in part, a preventable condition.

Incidence of type 1 diabetes mellitus in 0 to 14-yr-old children in Croatia--2004 to 2012 study

BACKGROUND

The incidence of type 1 diabetes mellitus (T1DM) among children and adolescents increased during the last 50 yr. The T1DM incidence in Croatia was 8.87/100.000/yr over 1995-2003, with an annual increase of 9%, which placed Croatia among countries with moderate risk for T1DM.

AIM

To investigate incidence rates and trends of T1DM from 2004 to 2012 in 0 to 14-yr-old Croatian children, and to compare the results with previous studies in Croatia and other European countries.

METHODS

T1DM crude incidence rates are estimated for the entire group and three subgroups: 0-4, 5-9, and 10-14 yr. Standardized incidence is calculated using the method of direct standardization according to World Health Organization (WHO) standard world population. The incidence rates by gender, age groups, seasonality, and calendar year, and their interactions were analyzed using Poisson regression model.

RESULTS

A total of 1066 cases were ascertained over 2004-2012. The standardized incidence was 17.23/100.000/yr (95% CI: 16.19-18.26), with no significant differences in incidence rates or trends between boys and girls. Statistically significant annual increase of 5.87% (p < 0.001) was found for the whole group, and for the subgroups 5-9 yr (6.82%; p < 0.001) and 10-14 yr (7.47%; p < 0.001). In the youngest subgroup (0-4 yr), annual increase was lower (2.43%; p = 0338) and not statistically significant.

CONCLUSION

The incidence of childhood T1DM is increasing in Croatia, thus placing Croatia among countries with high risk for T1DM. The annual increment of 5.87% is considerably lower than 9.0% reported earlier, but still higher than the European average (3.9%). The increase in incidence ceased in youngest children.

Incidence of type 1 diabetes among Polish children ages 0-14 years from 1989-2012

AIMS

The incidence of pediatric type 1 diabetes mellitus (T1DM) in Poland is intermediate relative to the rest of the world. T1DM prevalence in the region of Silesia approximates national estimates for all of Poland. This epidemiologic study aimed to analyze the changes in incidence rates of T1DM among children ages 0-14 years from 1989 to 2012 in this region.

METHODS

Data collection methods for the registry followed EURODIAB criteria. To estimate overall population size, data from the Central and regional Statistical Office in Katowice were used. T1DM incidence rates/100,000 children ages 0-14 years/annum and their 95 % CI were calculated for all children and in age subgroups (0-4, 5-9, 10-14 years). For comparative analysis incidence rates were age and sex standardized to the population of Poland in 2005. For statistical analyses open source R Bioconductor software was used.

RESULTS

During this 24-year period, 2,215 new cases (1,146 boys) were diagnosed. The standardized incidence rate rose about 7 % annually. The mean standardized incidence rates estimated in four 6-year time periods (1989-1994, 1995-2000, 2001-2006, 2007-2012) separately showed significant increases from 5.80/100,000/year (1989-1994) through 10.44/100,000/year (1995-2000) and 15.05/100,000/year (2001-2006) to 18.94/100,000/year (2007-2012). From 1989 to 2012, the greatest relative rise in annual incidence (/100,000/year) was among the very young: 2.58-14.00 (0-4 years); 4.96-19.43 (5-9 years); 8.84-22.15 (10-14 years). The highest average annual increment of the incidence rate was in the middle age subgroup (5-9 years). No significant sex difference was observed.

CONCLUSIONS

The overall incidence rate increased 3.8 times, suggesting an epidemic of pediatric T1DM in Silesia, Poland. These temporal changes confirm that Poland currently has one of the highest incidence rates of pediatric T1DM in Europe.

Diabetes in Europe: an update

Diabetes is among the leading causes of death in the IDF Europe Region (EUR), continues to increase in prevalence with diabetic macro- and microvascular complications resulting in increased disability and enormous healthcare costs. In 2013, the number of people with diabetes is estimated to be 56 million in EUR with an overall estimated prevalence of 8.5%. However, estimates of diabetes prevalence in 2013 vary widely in the 56 diverse countries in EUR from 2.4% in Moldova to 14.9% in Turkey. Trends in diabetes prevalence also vary between countries with stable prevalence since 2002 for many countries but a doubling of diabetes prevalence in Turkey. For 2035, a further increase of nearly 10 million people with diabetes is projected for the EUR. Prevalence of type 1 has also increased over the past 20 years in EUR and there was estimated to be 129,350 cases in children aged 0-14 years in 2013. Registries provide valid information on incidence of type 1 diabetes with more complete data available for children than for adults. There are large differences in distribution of risk factors for diabetes at the population level in EUR. Modifiable risk factors such as obesity, physical inactivity, smoking behaviour (including secondhand smoking), environmental pollutants, psychosocial factors and socioeconomic deprivation could be tackled to reduce the incidence of type 2 diabetes in Europe. In addition, diabetes management is a major challenge to health services in the European countries. Improved networking practices of health professionals and other stakeholders in combination with empowerment of people with diabetes and continuous quality monitoring need to be further developed in Europe.

Diabetes in the young - a global view and worldwide estimates of numbers of children with type 1 diabetes

This paper describes the methodology, results and limitations of the 2013 International Diabetes Federation (IDF) Atlas (6th edition) estimates of the worldwide numbers of prevalent cases of type 1 diabetes in children (<15 years). The majority of relevant information in the published literature is in the form of incidence rates derived from registers of newly diagnosed cases. Studies were graded on quality criteria and, if no information was available in the published literature, extrapolation was used to assign a country the rate from an adjacent country with similar characteristics. Prevalence rates were then derived from these incidence rates and applied to United Nations 2012 Revision population estimates for 2013 for each country to obtain estimates of the number of prevalent cases. Data availability was highest for the countries in Europe (76%) and lowest for the countries in sub-Saharan Africa (8%). The prevalence estimates indicate that there are almost 500,000 children aged under 15 years with type 1 diabetes worldwide, the largest numbers being in Europe (129,000) and North America (108,700). Countries with the highest estimated numbers of new cases annually were the United States (13,000), India (10,900) and Brazil (5000). Compared with the prevalence estimates made in previous editions of the IDF Diabetes Atlas, the numbers have increased in most of the IDF Regions, often reflecting the incidence rate increases that have been well-documented in many countries. Monogenic diabetes is increasingly being recognised among those with clinical features of type 1 or type 2 diabetes as genetic studies become available, but population-based data on incidence and prevalence show wide variation due to lack of standardisation in the studies. Similarly, studies on type 2 diabetes in childhood suggest increased incidence and prevalence in many countries, especially in Indigenous peoples and ethnic minorities, but detailed population-based studies remain limited.

Incidence of type 1 diabetes in Norway among children aged 0-14 years between 1989 and 2012: has the incidence stopped rising? Results from the Norwegian Childhood Diabetes Registry

AIMS/HYPOTHESIS

Our study aimed to describe the incidence of type 1 diabetes in children below 15 years of age in Norway during the period 1989-2012 and to assess the regional variation during 2004-2012. We further set out to estimate the completeness of ascertainment in the Norwegian Childhood Diabetes Registry (NCDR).

METHODS

Incident cases of type 1 diabetes were registered in the NCDR and incidence rates were modelled using Poisson regression. Ascertainment for 2005-2008 was estimated using capture-recapture methodology by using data from the Norwegian Prescription Database (NorPD), a nationwide register established in 2004, which included insulin prescribed and dispensed at pharmacies to individual patients. Population data were obtained from Statistics Norway.

RESULTS

Observed incidence rates for 1989-2012 suggested three distinct time segments: in 1989-1996, the average incidence rate was 22.6 per 100,000 person-years (95% CI 21.4, 23.7); in 1996-2004, the average incidence rate was 28.4 per 100,000 person-years (95% CI 27.3, 29.6); and from 2004 to 2012, the average incidence rate per 100,000 person-years was 32.7 (95% CI 31.5, 34.0). After adjustment for age and sex, the estimated change per year was 1.8% for 1989-1996 (95% CI -0.07, 3.6; p = 0.059), 3.4% for 1996-2004 (95% CI 2.2, 4.7; p < 0.0001) and 0.3% for 2004-2012 (95% CI -0.9, 1.6; p = 0.64). The highest incidence was in the age group 10-14 years for both sexes. A significant regional variation in incidence was observed (p < 0.001). Completeness of ascertainment in the NCDR was estimated to be 91%.

CONCLUSIONS/INTERPRETATION

The previously observed increase in incidence of type 1 diabetes has levelled off and remained essentially constant at 32.7 per 100,000 person-years during 2004-2012. There is a significant variation in type 1 diabetes incidence within Norway.

The emerging global epidemic of type 1 diabetes

Type 1 diabetes mellitus (T1D) can occur at any age, with a peak in incidence around puberty. Classification between T1D and type 2 diabetes becomes more challenging with increasing age of onset of T1D over time develops in genetically predisposed individuals. The main susceptibility is conferred with human leukocyte antigen (HLA) genes. Some of the geographic variation in incidence and familial aggregation is explained by differences in HLA haplotypes. In many populations, the incidence is somewhat higher in males than in females, and a 1.3- to 2.0-fold male excess in incidence after about 15 years of age exists in most populations. The incidence of childhood-onset T1D varies markedly among countries. East Asian and native American populations have low incidences (approximately 0.1-8 per 100 000/year), while the highest rates are found in Finland (>60 per 100 000/year), Sardinia (40 per 100 000/year), and Sweden (47 per 100 000/year). The risk is highest in European-derived populations. About 10 %-20 % of newly diagnosed childhood cases of T1D have an affected first-degree relative. Those with an affected sibling or parent have a cumulative risk of 3 %-7 % up to about 20 years of age, as compared with <1 % in the general population. The cumulative incidence among the monozygotic co-twins of persons with T1D is less than 50 %. Thus, the majority of genetically predisposed people do not develop T1D. Studies assessing temporal trends have shown that the incidence of childhood-onset T1D has increased in all parts of the world. The average relative increase is 3 %-4 % per calendar year. For instance, in Finland, the incidence today is 5 times higher than 60 years ago. At the same time, the age at onset of T1D in children has become younger. It is strongly believed that nongenetic factors are important for the development of T1D and its increase, but the causative evidence is missing. The causes for this increasing trend and current epidemic still remain unknown.

Type I diabetes among children and young adults: the role of country of birth, socioeconomic position and sex

OBJECTIVE

To investigate associations between country of birth, parental country of birth, and education with respect to incidence rate and time trends of type 1 diabetes mellitus (T1DM) among children and young adults.

METHODS

We followed a nation-wide cohort of 4 469 671 males and 4 231 680 females aged 0-30 years between 1969 and 2008. Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) for T1DM were calculated using Poisson regression models. We further calculated age-standardized rates (ASRs) of T1DM, using the world population as standard.

RESULTS

During the study period, the ASR of T1DM increased among children younger than 15 years, but not among young adults (15-30 years). Compared with Swedish-born children, male and female immigrant children had 44 and 42% lower IRR of TIDM, respectively. Among offspring to immigrants, corresponding decreases in IRRs were 27 and 24%, respectively. Compared with children to parents with high education, male children to parents with low education had a 10% decreased IRR of T1DM, while no effect was observed among females. The IRR of T1DM increased with increasing age and calendar time of follow-up in both sexes (p-for trend <0.0001). In young adults, the IRR among immigrants decreased by 32% in males and 22% in females, while corresponding reductions in IRRs were less in offspring to immigrants.

CONCLUSIONS

We found a lower IRR of T1DM among offspring to immigrants, but especially among young immigrants compared with Sweden-born individuals. The findings show that environmental factors are important in the etiology of T1DM.