Incidence of type 1 diabetes mellitus in the 0- to 17-yr-old Israel population, 1997-2003

Replacing Cereal with Ultraprocessed Foods in Pig Diets Does Not Adverse Gut Microbiota, L-glutamate Uptake, or Serum Insulin

BACKGROUND

Using ultraprocessed food (UPF) to replace traditional feed ingredients offers a promising strategy for enhancing food production sustainability.

OBJECTIVE

To analyze the impact of salty and sugary UPF on gut microbiota, amino acids uptake, and serum analytes in growing and finishing pig.

METHODS

Thirty-six Swiss Large White male castrated pigs were assigned to 3 experimental diets: 1) standard (ST), 0% UPF; 2) 30% conventional ingredients replaced by sugary (SU) UPF; and 3) 30% conventional ingredients replaced by salty (SA) UPF. The next-generation sequencing was used to characterize the fecal microbiota. Transepithelial electrical resistance and the active uptake of selected amino acids in pig jejuna were also evaluated. Data were enriched with measurements of fecal volatile fatty acids and serum urea, minerals, and insulin. All data analyses were run in R v4.0.3. The packages phyloseq, vegan, microbiome, and microbiomeutilities were used for microbiota data analysis. The remaining data were analyzed by analysis of variance using linear mixed-effects regression models.

RESULTS

The UPF did not affect fecal microbiota abundance or biodiversity. The Firmicutes to Bacteroidetes ratio remained unaffected. SU-induced increase in the Anaerostipes genus suggested altered glucose metabolism, whereas SA increased the abundance of CAG-352 and p-2534-18B. No effects on fecal volatile fatty acids were observed. Assumptions of UPF negatively affecting small intestinal physiology were not supported by the measurements of transepithelial electrical resistance in pigs. Active amino acids uptake tests showed potential decrease in L-glutamate absorption in the SA compared with the SU diet. Blood serum analysis indicated no adverse effects on urea, calcium, magnesium, or potassium concentration but the SU group resulted in a lower blood serum insulin concentration at the time of blood collection.

CONCLUSIONS

When incorporated at 30% into a standard growing finishing diet for pigs, UPF does not have detrimental effects on gut microbiota, intestinal integrity, and blood mineral homeostasis.

Birth during the moderate weather seasons is associated with early onset of type 1 diabetes in the Mediterranean area

AIM

To assess the association of seasonal and perinatal parameters with early age of type 1 diabetes (T1D) onset.

METHODS

A cross-sectional review of all medical records of T1D patients born between the years 1990 and 2005, and diagnosed before/by the age of 10 years, from 13 university-affiliated paediatric medical centres in Israel, was performed. Data included: gender, ethnicity, seasons of birth and disease onset, birth gestational age and weight, and autoimmune diseases of the probands and their first-degree family members. Statistical analysis included the Chi-square test or Mann-Whitney test, as appropriate and multivariate regression analysis.

RESULTS

Enrolled were 1571 T1D patients at a median age of T1D onset 6.9 years (IQR 4.4,8.4); 336 of them presented before 4 years of age. The median age of this group was 2.5 years (IQR 1.7,3.2), and of the 1235 patients who presented after 4 years of age, median presentation age was 7.5 years (IQR 6.1,8.8). Multivariate regression analysis demonstrated that a more recent birth year; OR = 1.06, 95% CI 1.02-1.1, P = 0.003, and birth during the moderate weather months (September, October, March, and April) were significantly associated with younger age at T1D onset; OR = 1.68, 95% CI 1.17-2.4, P = 0.005.

CONCLUSIONS

Our novel finding demonstrates the association between younger than 4 years old age at presentation and birth during moderate weather months. The results also support previous reports, that there is a slight increase in the annual incidence of T1D in the youngest age groups.

Prevalence and incidence of type 1 diabetes in the world: a systematic review and meta-analysis

Background: Diabetes is referred to a group of diseases characterized by high glucose levels in blood. It is caused by a deficiency in the production or function of insulin or both, which can occur because of different reasons, resulting in protein and lipid metabolic disorders. The aim of this study was to systematically review the prevalence and incidence of type 1 diabetes in the world. Methods: A systematic search of resources was conducted to investigate the prevalence and incidence of type 1 diabetes in the world. The databases of Medline (via PubMed and Ovid),ProQuest, Scopus, and Web of Science from January 1980 to September 2019 were searched to locate English articles. The located articles were screened in multiple levels of title, abstract,and full-text and final studies that met the inclusion criteria were retrieved and included in the study. Results: From 1202 located articles, 193 studies were included in this systematic review. The results of meta-analysis showed that the incidence of type 1 diabetes was 15 per 100,000 people and the prevalence was 9.5% (95% CI: 0.07 to 0.12) in the world, which was statistically significant. Conclusion: According to the results, the incidence and prevalence of type 1 diabetes are increasing in the world. As a result, insulin will be difficult to access and afford, especially in underdeveloped and developing countries.

Vitamin D status in Israeli pediatric type 1 diabetes patients: the AWeSoMe Study Group experience and literature review

Background The prevalence of both vitamin D (VitD) deficiency and type 1 diabetes mellitus (T1DM) has increased worldwide over the last few decades. The objectives of this study were: (1) to evaluate the prevalence of VitD deficiency and insufficiency among Israeli youth with T1DM and (2) to assess the association between VitD status, seasonality and T1D glycemic control characteristics. Methods This was a multi-centered, cross-sectional study. VitD levels were routinely tested during the years 2008-2011 in T1DM patients aged up to 21 years. Medical records were reviewed for demographic, clinical and laboratory characteristics. Results The study population consisted of 199 participants (53% males), mean age 12.24±4.11 years, mean T1DM duration 3.77±3.43 years. VitD levels were within the normal range in 19.6%, insufficient (15-29 ng/mL, 37-72 nmol/L) in 62.3% and deficient (<15 ng/mL, <37 nmol/L) in 18.1%. Mean VitD level was higher during the summer than during spring, autumn and winter (28.65 ng/mL, 23.16 ng/mL, 21.65 ng/mL, 17.55 ng/mL, respectively, p<0.001). Mean VitD level was higher among secular patients compared to the religious (whole-year heavily dressed) population (23.57 ng/mL, 15.54 ng/mL, respectively, p<0.001). VitD level was negatively associated with body mass index calculation of standard deviation scores (BMI-SDS), high-density lipoprotein (HDL) and age at diagnosis (r=-0.171, p=0.016; r=-0.149, p=0.043; r=-0.150, p=0.037, respectively). No association was demonstrated with disease duration and glycemic control indices and metabolic parameters. Conclusions VitD insufficiency is largely prevalent among Israeli youth with T1DM, as is in Israeli youth in general. The VitD level is associated with seasonality, clothing habits and BMI.

Global and regional estimates of the morbidity due to type I diabetes among children aged 0-4 years: a systematic review and analysis

Background

Epidemiology of type 1 diabetes mellitus (T1DM) among children aged 0-4 years globally is not well understood. We aim to assess the incidence of T1DM in low- and middle-income countries (LMIC) by conducting a systematic review of previous reports. We also aim to address possible contribution to child mortality and to identify any temporal trends.

Methods

A systematic review was performed using a carefully designed search strategy to explore MEDLINE, EMBASE and Global Health databases. Data was extracted from all studies that satisfied the inclusion criteria –a total of 83 records extracted from 26 830 sources that were analysed. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) process to assess quality of evidence and applied meta-analysis approaches to assess global and regional incidence and time trends.

Results

The overall pooled incidence of T1DM in children aged 0-4 years globally is 11.2 (95% CI = 10.0-12.3) per 100 000 child years. The regional incidence were the highest for European Region A (EUR A) at 15.5 (95% CI = 13.5-17.5) per 100 000 child years. EUR C had the incidence of 10.0 (95% CI = 6.5-13.6) and EUR B 5.8 (95% CI = 4.7-7.0), Region of the Americas A (AMR A) 11.4 (95% CI = 7.8-14.9), AMR B of 2.5 (95% CI = 0.2-4.8), Eastern Mediterranean Region (EMR B) 7.1 (95% CI = 4.2-10.0) and Western Pacific Region (WPR A) 7.0 (95% CI = 2.9-11.0) per 100 000 child years, while other regions had very low rates or no data. When data points were categorised in the study periods and re-analysed, an increasing trend of the T1DM incidence was observed, with the incidence of 20.9 (95% CI = 7.8-34.1) per 100 000 child years in the years 2010-2015, preceded by 13.2 (95% CI = 11.0-15.5) in 2000-2009 study period, 10.0 (95% CI = 8.4-11.7) in 1990-1999 and 8.3 (95% CI = 5.1-11.6) in 1980-1989, respectively. Although the data are scarce, and variation and uncertainty are large, we estimated that the number of new cases of T1DM among children aged 0-4 years in the world each year is between 100 000 and 150 000.

Conclusions

The identified large variation in incidence estimates for different parts of the world, along with scarcity of information and the identified strong temporal increase in T1DM incidence suggest a clear need for further research into this subject.

Effect of Socioeconomic Status and Ethnicity on Glycemic Control in Arab and Jewish Youth with Type 1 Diabetes Mellitus

OBJECTIVES

Research and theory suggests that socioeconomic status may affect diabetes control. We investigated the effect of socioeconomic status and ethnicity on glycated hemoglobin (HbA1c) in Arab and Jewish children with type 1 diabetes mellitus in northern Israel.

METHODS

Data were collected from medical records of 80 Arab and 119 Jewish children attending a pediatric diabetes clinic in a tertiary health care center. Multivariate regression analysis was used to assess factors independently affecting HbA1c level.

RESULTS

Mean age was 12.9±4.7 years. Arab families had more children compared to Jewish families (3.7±1.5 versus 2.9±1.2, respectively, P=0.0007). Academic education was significantly less common in Arab families (25% versus 66.2%, respectively, P=0.0001). Income of Jewish parents was significantly higher compared to that of Arab parents (7,868±2,018 versus 5,129±906 NIS/month, respectively, P=0.0001). Mean age at diagnosis of diabetes was 9.6±4.6 years and disease duration was 3.4±2.3 years in both groups. Half of Arab and Jewish children were treated with multiple insulin injections and half with insulin pumps. Mean number of self-glucose testing/day was higher in Jewish children than in Arab children (4.7±2.5 versus 4.0±1.5, respectively, P=0.033). Mean HbA1c was above recommendations, 9.5% (12.6 mmol/L) in Arab children and 8.7% (11.3 mmol/L) in Jewish children (P=0.004). In multivariate analysis, disease duration (P=0.010) and ethnicity (P=0.034 for Arabs versus Jews) were independently associated with HbA1c.

CONCLUSIONS

Both Arab and Jewish children failed to meet HbA1c goals, but this effect was significantly greater for Arabs. Ethnicity remained a predictor of failure even following adjustment for potential confounders.

The proportion of familial cases of type 1 diabetes is increasing simultaneously with the disease incidence: Eighteen years of the Israeli Pediatric Diabetes Registry

BACKGROUND

The global rise in incidence of type 1 diabetes (T1D) is too rapid to be attributed to susceptible genetic background, pinpointing a significant role for environmental factors. Unlike the theory that the need for genetic susceptibility has lessened over time, we hypothesized that the rise in T1D incidence is faster in a genetically susceptible population.

SUBJECTS AND METHODS

The study population comprised of 5080 patients aged 0 to 17 years who were reported to the National Israel Diabetes Registry between 1997 and 2014. The patients were divided into familial cases (first-degree relative has T1D), and sporadic cases. Demographic and clinical data were retrieved from the registry. The change in annual percent (from the entire cohort) was computed separately for the sporadic and familial cohorts.

RESULTS

The familial (n = 546; 10.7%) and sporadic (n = 4534; 89.3%) cases were comparable for gender, ethnicity, and age at diagnosis. Consanguinity was more common in the familial vs sporadic group (10% vs 6.1%; P = .001). The average annual percent change increased by 1.9% in the familial cases and decreased by 0.2% in the sporadic cases (P = .04).

CONCLUSIONS

The rapid rise in the proportion of familial cases of T1D suggests that environmental factors impose higher diabetogenic pressure in patients with a susceptible genetic background.

Registry of Youth Onset Diabetes in India (YDR): Rationale, Recruitment, and Current Status

BACKGROUND

With the aim of addressing the relative scarcity of information on youth-onset diabetes in India, the Indian Council of Medical Research (ICMR) decided to establish the Registry of People with Diabetes with Young Age at Onset (YDR) in 2006. The major objectives of YDR are to generate information on disease pattern or types of youth-onset diabetes including their geographical variations within India and to estimate the burden of diabetes complications.

METHODS

YDR is an observational multicenter clinic based registry enlisting physician diagnosed diabetes in individuals below 25 years of age. Diabetes was classified using symptom based clinical criteria. YDR data collection is coordinated through regional collaborating centers and their interacting reporting centers across India. A baseline and an annual follow-up proformas are used to obtain information on sociodemographic details, clinical profile, and anthropometric and laboratory measurements of the patients.

RESULTS

In phase 1, the registry has enrolled 5546 patients, in which type 1 diabetes mellitus (T1DM) was the most prevalent (63.9%), followed by youth-onset type 2 diabetes mellitus (T2DM) (25.3%).

CONCLUSION

This registry provides a unique opportunity to study the natural history of youth-onset diabetes in India.

Global epidemiology of type 1 diabetes in young adults and adults: a systematic review

Background

Although type 1 diabetes (T1D) can affect patients of all ages, most epidemiological studies of T1D focus on disease forms with clinical diagnosis during childhood and adolescence. Clinically, adult T1D is difficult to discriminate from certain forms of Type 2 Diabetes (T2D) and from Latent Autoimmune Diabetes in Adults (LADA).

We searched the information available worldwide on the incidence of T1D among individuals over 15 years of age, and which diagnostic criteria should be used use to qualify T1D in adults. We then studied the variation of T1D incidence with age in adults, and compared it to the incidence in the <15 years-old.

Methods

A systematic review of the literature was performed to retrieve original papers in English, French and Spanish published up to November 6, 2014, reporting the incidence of T1D among individuals aged over 15 years. The study was carried out according to the PRISMA recommendations.

Results

We retrieved information reporting incidence of T1D among individuals aged more than 15 years in 35 countries, and published in 70 articles between 1982 and 2014. Specific anti-beta-cell proteins or C-peptide detection were performed in 14 of 70 articles (20%). The most frequent diagnostic criteria used were clinical symptoms and immediate insulin therapy. Country-to-country variations of incidence in those aged >15 years paralleled those of children in all age groups. T1D incidence was larger in males than in females in 44 of the 54 (81%) studies reporting incidence by sex in people >15 years of age. The overall mean male-to-female ratio in the review was 1.47 (95% CI = 1.33-1.60, SD = 0.49, n = 54, p = <0.0001). Overall, T1D incidence decreased in adulthood, after the age of 14 years.

Conclusions

Few studies on epidemiology of T1D in adults are available worldwide, as compared to those reporting on children with T1D. The geographical variations of T1D incidence in adults parallel those reported in children. As opposed to what is known in children, the incidence is generally larger in males than in females. There is an unmet need to evaluate the incidence of autoimmune T1D in adults, using specific autoantibody detection, and to better analyze epidemiological specificities – if any – of adult T1D.

PROSPERO registration number

CRD42012002369.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-1591-y) contains supplementary material, which is available to authorized users.

Changes in intestinal tight junction permeability associated with industrial food additives explain the rising incidence of autoimmune disease

The incidence of autoimmune diseases is increasing along with the expansion of industrial food processing and food additive consumption. The intestinal epithelial barrier, with its intercellular tight junction, controls the equilibrium between tolerance and immunity to non-self-antigens. As a result, particular attention is being placed on the role of tight junction dysfunction in the pathogenesis of AD. Tight junction leakage is enhanced by many luminal components, commonly used industrial food additives being some of them. Glucose, salt, emulsifiers, organic solvents, gluten, microbial transglutaminase, and nanoparticles are extensively and increasingly used by the food industry, claim the manufacturers, to improve the qualities of food. However, all of the aforementioned additives increase intestinal permeability by breaching the integrity of tight junction paracellular transfer. In fact, tight junction dysfunction is common in multiple autoimmune diseases and the central part played by the tight junction in autoimmune diseases pathogenesis is extensively described. It is hypothesized that commonly used industrial food additives abrogate human epithelial barrier function, thus, increasing intestinal permeability through the opened tight junction, resulting in entry of foreign immunogenic antigens and activation of the autoimmune cascade. Future research on food additives exposure-intestinal permeability-autoimmunity interplay will enhance our knowledge of the common mechanisms associated with autoimmune progression.

Male-female differences in diabetic retinopathy?

The purpose of this paper is to review male-female differences in the incidence and prevalence of diabetes and diabetic retinopathy. These differences will be established primarily through results from our present research and a review of related literature. Previously, we have demonstrated that neuroretinal dysfunction can be used to predict the location of future retinopathy up to three years before it is manifest. Our current research suggests that, for type 2 diabetes, the normal differences in neuroretinal function between nondiabetic males and females under 50 years of age are altered in patients with type 2 diabetes. Furthermore, local neuroretinal function in type 2 diabetes is more abnormal in adult males compared with adult females. The literature also suggests that there are male-female differences in the occurrence of diabetes. In adolescence, the incidence of type 1 diabetes is greater in males, whereas in type 2 diabetes, the incidence is greater in females. This excess of females in type 2 diabetes shifts to a more equal incidence between the two sexes in adults. In addition, advanced retinopathy in type 1 diabetes appears to be more common in males, and the presence and severity of diabetic retinopathy at the time of diagnosis in type 2 diabetes appears to be more associated with male sex. Although the reasons for male-female differences identified in this review are unknown, sex appears to be a significant factor in certain aspects of diabetes incidence and diabetic retinopathy.

Decrease in frequency of ketoacidosis at diabetes onset over the past two decades - perspectives of a paediatric tertiary care centre

AIMS

To determine whether the frequency and severity of diabetic ketoacidosis and the clinical characteristics of children at diagnosis of Type 1 diabetes mellitus have changed over the past decades among patients under surveillance of a tertiary paediatric centre.

METHODS

In three time-periods, 75 (1986-1987), 86 (1996-1997) and 245 (2006-2007) patients at mean age 10.1 ± 4.7 years (0.6-20.0) were diagnosed with new-onset Type 1 diabetes. Data on clinical characteristics and laboratory evaluation at diagnosis retrieved from the patients' files . Comparative analysis was performed between the three time periods.

RESULTS

The frequency of diabetic ketoacidosis at diagnosis was 40% in 1986-1987, 41.8% in 1996-1997 and 29.4% in 2006-2007; the last rate was significantly lower (P=0.04). No significant differences in the proportions of patients with severe or moderate diabetic ketoacidosis were found over time. Mean weight standard deviation score significantly increased from -0.72 ± 1.8 in 1986-1987 to -0.27 ± 1.2 in 2006-2007 (P<0.05), while percentage weight loss (∼6.5%) before diagnosis remained unchanged. In 2006-2007 a higher proportion of children had glucose testing at the community clinic before diagnosis, than in the earlier years (73.1 vs. 59.6%, P=0.003).

CONCLUSIONS

The overall frequency of diabetic ketoacidosis in children with newly diagnosed Type 1 diabetes has decreased in the past decade, although the degree of metabolic decompensation has remained unchanged.

Increase in the incidence of type 1 diabetes in Israeli children following the Second Lebanon War

BACKGROUND

Type 1 diabetes is an autoimmune disease occurring in genetically susceptible individuals. The precipitating cause is unclear. Recently, the Second Lebanon War exposed a large civilian population in northern Israel to significant psychological stress in the form of repeated barrages of missile attacks.

HYPOTHESIS

We hypothesized that trends in regional incidence of type 1 diabetes before and after the war would reflect an association with stress.

METHODS

All type 1 diabetes patients aged 0-17 yr who were reported to the Israel Juvenile Diabetes Register (n = 1822) in the four pre-war (2002-2005) and two post-war years (2006-2007) were included in the study. The patients were stratified by gender, age, ethnicity, family history of type 1 diabetes, season at diagnosis, and region of residency, namely, those who lived in the northern regions that were attacked and those in other regions.

RESULTS

The post-war incidence of type 1 diabetes was increased in the northern regions (rate ratio, RR = 1.27; p = 0.037), with no change in the other regions. This change was more prominent in males (RR = 1.55; p = 0.005) but similar in summer and winter, in different ages, and in different ethnic groups. There was no change in the proportion of new patients with a family history of the disease.

CONCLUSIONS

For the first time in a large population, we found a positive association between the trauma of war and an increase in the incidence of type 1 diabetes in children and adolescents. The increase in incidence was not associated with genetic susceptibility to the disease.

A retrospective study of the incidence of diagnosed Type 1 diabetes among children and adolescents in a large health organization in Israel, 2000-2008

AIMS

To determine the incidence and examine temporal trends of Type 1 diabetes among children aged < 18 years, in a large Israeli health organization.

METHODS

All incident Type 1 diabetes cases diagnosed between 2000 and 2008 were ascertained from an automated diabetes registry based on members' electronic records and validated by comparison with the Israel Juvenile Diabetes Register.

RESULTS

During the study period, a total of 648 incident cases of Type 1 diabetes were identified. The average annual age-and-sex-standardized incidence was 11.09 per 100,000 person-years. There was an annual 5.82% (95% CI 1.80-9.98%) rise in incidence, with a greater relative increase in toddlers under 5 years of age. Incidence increased with age and demonstrated seasonal variation. Mean age at onset of diabetes significantly (P = 0.07) decreased from 10.21 years (SD = 4.48) in 2000-2002 to 9.25 years (SD = 4.54) in 2006-2008. Among very young patients (< 5 years), average blood glucose values at diagnosis dropped from 32.4 mmol/l (SD = 9.5) to 19.5 mmol/l (SD = 11.0) over the study period, with little change in average glucose for older children.

CONCLUSIONS

Incidence of diagnosed Type 1 diabetes continues to increase in Israel at a rate that is high compared with similar American and European populations. At the same time, the clinical presentation of children is changing.

The geoepidemiology of type 1 diabetes

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by absolute insulin deficiency resulting from the progressive immune-mediated destruction of pancreatic islet beta cells. It is thought to be triggered by as yet unidentified environmental factors in genetically susceptible individuals, the major genetic contribution coming from loci within the HLA complex, in particular HLA class II. The worldwide incidence of T1D varies by at least 100-fold, being highest in Finland and Sardinia (Italy) and lowest in Venezuela and China. The incidence has been increasing worldwide at an annual rate of approximately 3%. While genetic factors are thought to explain some of the geographic variability in T1D occurrence, they cannot account for its rapidly increasing frequency. Instead, the declining proportion of newly diagnosed children with high-risk genotypes suggests that environmental pressures are now able to trigger T1D in genotypes that previously would not have developed the disease during childhood. Although comparisons between countries and regions with low and high-incidence rates have suggested that higher socioeconomic status and degree of urbanization are among the environmental factors that play a role in the rising incidence of T1D, the findings are too inconsistent to allow firm conclusions. Morbidity and mortality as well as causes of death also show considerable geographic variation. While glycemic control has been identified as a major predictor of the micro- and macrovascular complications of T1D and shows considerable geographical variability, it does not appear to be the only factor involved in the regional differences in complication rates. The role of genetics in susceptibility to nephropathy, retinopathy and other diabetic complications largely remains to be explored.

Australia's national trends in the incidence of Type 1 diabetes in 0-14-year-olds, 2000-2006

AIMS

To determine the national incidence of Type 1 diabetes in children aged 0-14 years and examine trends in incidence between 2000 and 2006 by age, sex and calendar year.

METHODS

Case ascertainment was from the Australian National Diabetes Register, a prospective population-based incidence register established in 1999, with two sources of ascertainment: the National Diabetes Services Scheme and the Australasian Paediatric Endocrine Group's state-based registers. Denominator data were from the Australian Bureau of Statistics.

RESULTS

There were 6350 new cases of Type 1 diabetes (3323 boys and 3027 girls). Case ascertainment was 97.1% complete using the capture-recapture method. The mean adjusted incidence rate for 2000-2006 was 21.6 per 100,000 person-years [95% confidence interval (CI) 21.0, 22.1], and increased from 19.8 in 2000 to 23.4 per 100,000 in 2006, an average increase of 2.8% (95% CI 1.5, 4.1) per year. Mean incidence for the 7-year period increased with age, and was significantly higher in boys aged 0-4 years and 10-14 years than in girls of the same age.

CONCLUSIONS

The incidence of Type 1 diabetes among 0-14-year-olds in Australia is very high compared with available data from many other countries. The rate of increase observed globally in the last decade has continued well into this decade in Australia. The rising incidence cannot be explained by changes in genetic susceptibility; there is an urgent need to examine the environmental factors that have contributed to this increase. The findings of this study also have important implications for resource planning.

Increasing incidence of type 1 diabetes in children aged 0-14 years in Harbin, China (1990-2000)

AIMS

(1) To determine the incidence of type 1 diabetes mellitus in children aged<15 years in Harbin, China and (2) to examine the trend in incidence over the period from 1990 to 2000.

METHODS

Newly diagnosed cases of type 1 diabetes from 1990 to 2000 were identified among 1,286,154 Chinese children aged 0-14 years in Harbin. The primary source of case ascertainment was from hospital records and the secondary source from the health records of school clinics.

RESULTS

One hundred and three cases were identified during 1990 and 2000. The annual incidence rate was 0.73 per 100,000 (95% CI: 0.59-0.88 per 100,000). No significant difference between males and females in the incidence of type 1 diabetes was observed. The incidence was significantly associated with age. With those aged<5 years as reference, the rate ratios were 2.06 and 4.1 for those aged 5-9 and 10-14 years, respectively. The incidence was higher in urban than in suburban regions, particularly among those aged 10-14 years. No significant seasonality was observed. There was a significant increasing trend in the incidence of type 1 diabetes during the period of 1990 and 2000, with an annual increase of 7.4% (95% CI: 1.6-13.5%).

CONCLUSIONS

There is a significantly increasing trend in the incidence of type 1 diabetes among children in Harbin. Increased number of cases has important implications for diabetes care providers. Understanding the etiology of this rise is critical for developing preventive measures to halt the trend.