Seasonal variation in month of diagnosis in children with type 1 diabetes registered in 23 European centers during 1989-2008: little short-term influence of sunshine hours or average temperature

BACKGROUND

The month of diagnosis in childhood type 1 diabetes shows seasonal variation.

OBJECTIVE

We describe the pattern and investigate if year-to-year irregularities are associated with meteorological factors using data from 50 000 children diagnosed under the age of 15 yr in 23 population-based European registries during 1989-2008.

METHODS

Tests for seasonal variation in monthly counts aggregated over the 20 yr period were performed. Time series regression was used to investigate if sunshine hour and average temperature data were predictive of the 240 monthly diagnosis counts after taking account of seasonality and long term trends.

RESULTS

Significant sinusoidal pattern was evident in all but two small centers with peaks in November to February and relative amplitudes ranging from ± 11 to ± 38% (median ± 17%). However, most centers showed significant departures from a sinusoidal pattern. Pooling results over centers, there was significant seasonal variation in each age-group at diagnosis, with least seasonal variation in those under 5 yr. Boys showed greater seasonal variation than girls, particularly those aged 10-14 yr. There were no differences in seasonal pattern between four 5-yr sub-periods. Departures from the sinusoidal trend in monthly diagnoses in the period were significantly associated with deviations from the norm in average temperature (0.8% reduction in diagnoses per 1 °C excess) but not with sunshine hours.

CONCLUSIONS

Seasonality was consistently apparent throughout the period in all age-groups and both sexes, but girls and the under 5 s showed less marked variation. Neither sunshine hour nor average temperature data contributed in any substantial way to explaining departures from the sinusoidal pattern.

Glycaemic control of Type 1 diabetes in clinical practice early in the 21st century: an international comparison

AIMS

Improving glycaemic control in people with Type 1 diabetes is known to reduce complications. Our aim was to compare glycaemic control among people with Type 1 diabetes using data gathered in regional or national registries.

METHODS

Data were obtained for children and/or adults with Type 1 diabetes from the following countries (or regions): Western Australia, Austria, Denmark, England, Champagne-Ardenne (France), Germany, Epirus, Thessaly and Thessaloniki (Greece), Galway (Ireland), several Italian regions, Latvia, Rotterdam (The Netherlands), Otago (New Zealand), Norway, Northern Ireland, Scotland, Sweden, Volyn (Ukraine), USA and Wales) from population or clinic-based registries. The sample size with available data varied from 355 to 173 880. Proportions with HbA1c < 58 mmol/mol (< 7.5%) and ≥ 75 mmol/mol (≥ 9.0%) were compared by age and sex.

RESULTS

Data were available for 324 501 people. The proportions with HbA1c 58 mmol/mol (< 7.5%) varied from 15.7% to 46.4% among 44 058 people aged < 15 years, from 8.9% to 49.5% among 50 766 people aged 15-24 years and from 20.5% to 53.6% among 229 677 people aged ≥ 25 years. Sex differences in glycaemic control were small. Proportions of people using insulin pumps varied between the 12 sources with data available.

CONCLUSION

These results suggest that there are substantial variations in glycaemic control among people with Type 1 diabetes between the data sources and that there is room for improvement in all populations, especially in young adults.

Impact of regular physical activity on blood glucose control and cardiovascular risk factors in adolescents with type 2 diabetes mellitus--a multicenter study of 578 patients from 225 centres

INTRODUCTION

Regular physical activity (RPA) is a major therapeutic recommendation in children and adolescents with type 2 diabetes mellitus (T2DM). We evaluated the association between frequency of RPA and metabolic control, cardiovascular risk factors, and treatment regimes.

METHODS

The Pediatric Quality Initiative (DPV), including data from 225 centers in Germany and Austria, provided anonymous data of 578 patients (10-20 yr; mean 15.7 ± 2.1 yr; 61.9% girls) with T2DM. Patients were grouped by the frequency of their self-reported RPA per week: RPA 0, none; RPA 1, 1-2×/wk; RPA 2, >2×/wk.

RESULTS

The frequency of RPA ranged from 0 to 9×/wk (mean 1.1×/wk ±1.5). 55.7% of the patients reported no RPA (58.1% of the girls). Hemoglobin A1c (HbA1c) differed significantly among RPA groups (p < 0.002), being approximately 0.8 percentage points lower in RPA 2 compared to RPA 0. Body mass index (BMI-SDS) was higher in the groups with less frequent RPA (p < 0.00001). Multiple regression analysis revealed a negative association between RPA and HbA1c (p < 0.0001) and between RPA and BMI-SDS (p < 0.01). The association between RPA and high density lipoprotein (HDL)-cholesterol was positive (p < 0.05), while there was no association to total cholesterol, low density lipoprotein (LDL)-cholesterol or triglycerides. Approximately 80% of the patients received pharmacological treatment (oral antidiabetic drugs and/or insulin) without differences between RPA groups.

CONCLUSION

More than half of the adolescents with T2DM did not perform RPA. Increasing physical activity was associated with a lower HbA1c, a lower BMI-SDS, a higher HDL-cholesterol, but not with a difference in treatment regime. These results suggest that regular exercise is a justified therapeutic recommendation for children and adolescents with T2DM.

Treatment of young patients with HNF1A mutations (HNF1A-MODY)

AIM

Children and adolescents with a molecular diagnosis of HNF1A-MODY should be treated with oral sulfonylurea according to current International Society for Pediatric and Adolescent Diabetes (ISPAD) guidelines.

METHODS

We surveyed the German-Austrian DPV database of 50 043 people and included 114 patients with a confirmed molecular-genetic diagnosis of HNF1A mutation and diabetes onset at below age 18 years. We analysed hypoglycaemic episodes, metabolic control (HbA1c ) and other clinical variables according to treatment groups.

RESULTS

People with HNF1A-MODY were included and analysed according to treatment with insulin alone (n = 34), sulfonylurea (n = 30), meglitinides (n = 22) or lifestyle (n = 28). In those receiving any drug treatment (n = 86), severe hypoglycaemia did not occur with meglitinide and was highest (at 3.6 events per 100 patient-years) with insulin. HbA1c was highest with insulin treatment (insulin = 58 mmol/mol, 7.5%; sulfonylurea = 55 mmol/mol, 7.2%; meglitinides = 52 mmol/mol, 6.9%; P = 0.008), whereas weight (BMI SD score), serum lipids and blood pressure were not different.

CONCLUSIONS

Of note, 40% of people with HNF1A-MODY and medical treatment were receiving insulin alone and thus were not being treated in line with up-to-date International Society for Pediatric and Adolescent Diabetes/International Diabetes Federation guidelines, despite insulin treatment being associated with worse metabolic control and the risk of hypoglycaemia. The unlicensed use of oral drugs in patients below age 18 years and adherence by both doctors and patients to the initial insulin treatment might contribute to this finding.

Trends in childhood type 1 diabetes incidence in Europe during 1989-2008: evidence of non-uniformity over time in rates of increase

AIMS/HYPOTHESIS

The aim of the study was to describe 20-year incidence trends for childhood type 1 diabetes in 23 EURODIAB centres and compare rates of increase in the first (1989-1998) and second (1999-2008) halves of the period.

METHODS

All registers operate in geographically defined regions and are based on a clinical diagnosis. Completeness of registration is assessed by capture-recapture methodology. Twenty-three centres in 19 countries registered 49,969 new cases of type 1 diabetes in individuals diagnosed before their 15th birthday during the period studied.

RESULTS

Ascertainment exceeded 90% in most registers. During the 20-year period, all but one register showed statistically significant changes in incidence, with rates universally increasing. When estimated separately for the first and second halves of the period, the median rates of increase were similar: 3.4% per annum and 3.3% per annum, respectively. However, rates of increase differed significantly between the first half and the second half for nine of the 21 registers with adequate coverage of both periods; five registers showed significantly higher rates of increase in the first half, and four significantly higher rates in the second half.

CONCLUSIONS/INTERPRETATION

The incidence rate of childhood type 1 diabetes continues to rise across Europe by an average of approximately 3-4% per annum, but the increase is not necessarily uniform, showing periods of less rapid and more rapid increase in incidence in some registers. This pattern of change suggests that important risk exposures differ over time in different European countries. Further time trend analysis and comparison of the patterns in defined regions is warranted.

Concurrent FOXP3- and CTLA4-associated genetic predisposition and skewed X chromosome inactivation in an autoimmune disease-prone family

CLTA4 is relevant for FOXP3(+)Treg cells, and the link between skewed X chromosome inactivation (XCI) and autoimmunity is recognized. The observation of immune dysregulation polyendocrinopathy enteropathy X-linked syndrome and multiorgan endocrine autoimmune phenomena in various members of one family, associated with a CTLA4 polymorphism and skewed XCI, provides an in vivo model of how mechanisms of immune dysregulation may cooperate.

Microvascular autoregulation in children and adolescents with type 1 diabetes mellitus

AIMS/HYPOTHESIS

Deterioration of microvascular function may have an early onset in individuals with type 1 diabetes mellitus. We hypothesised that microvascular autoregulation is impaired in children with type 1 diabetes and can be detected non-invasively by postocclusive reactive hyperaemia (PORH).

METHODS

Microvascular autoregulation was assessed in 58 children with type 1 diabetes and 58 age- and sex-matched healthy controls by PORH using laser Doppler fluxmetry. Baseline perfusion, biological zero (defined as a 'no flow' laser Doppler signal during suprasystolic occlusion), peak perfusion following occlusion, time to peak and recovery time (time until baseline perfusion is resumed) were recorded and compared between the groups.

RESULTS

Peak perfusion was higher in children with type 1 diabetes than in healthy controls (1.7 ± 0.93 AU [arbitrary units] vs 1.29 ± 0.46 AU; p = 0.004), and biological zero was lower in children with type 1 diabetes vs controls (0.14 ± 0.04 AU vs 0.19 ± 0.04 AU; p < 0.0001). No differences were seen between the groups in baseline perfusion, time to peak during PORH and recovery time following PORH.

CONCLUSIONS/INTERPRETATION

PORH reveals impaired microvascular autoregulation in children with type 1 diabetes. The higher peak perfusion might reflect a decline in the vasoconstrictive ability of arteriolar smooth muscle cells upstream of capillary beds in children with type 1 diabetes.

Reclassification of diabetes type in pediatric patients initially classified as type 2 diabetes mellitus: 15 years follow-up using routine data from the German/Austrian DPV database

OBJECTIVE

To examine change of diagnosis in patients from the German/Austrian multicenter DPV (Diabetes Patienten Verlaufsdokumentation) database initially classified as type 2 diabetes.

METHODS

Patients aged ≤20 years at onset, diagnosed between 1995 and 2010 were followed for at least 6 months. Chi-square/Wilcoxon tests were performed to compare patient groups according to diabetes type after reclassification.

RESULTS

From 580 study patients, 60 (10.3%) were reclassified, on average 2.4 years after initial diagnosis as follows: 23 (38.3%) as type 1 diabetes; 9 (15%) as maturity onset diabetes of the young (MODY); 20 (33.3%) as "other specific diabetes forms" and 8 (13.3%) as "remission" of type 2 diabetes. Patients reclassified to type 1 were significantly younger (13.5 ± 2.9 versus 14.0 ± 2.6; p=0.027) and more often β-cell antibody positive at disease onset (80.0% versus 31.2%; p=0.002), while patients reclassified as MODY had significantly lower BMI-SDS values than 520 patients with confirmed type 2 diabetes (2.5 ± 1.1 versus 0.9 ± 1.1; p<0.001). The latter were also considerably more obese than patients in "remission" and those reclassified to "other specific diabetes forms".

CONCLUSION

About 10% of patients in the DPV database, initially diagnosed as type 2 diabetes, were retrospectively reclassified.

Genetic and clinical characteristics of patients with HNF1A gene variations from the German-Austrian DPV database

OBJECTIVE

To determine prevalence, genetic and phenotype characteristics of patients with hepatocyte nuclear factor-1α (HNF1A) variants in the Diabetes Patienten Verlaufsdokumenation (DPV) multicentre database and to examine the influence of HNF1A mutation type, or location on clinical phenotypes.

PATIENTS AND METHODS

Seventy-one DPV patients were labelled as HNF1A-MODY (MODY3). Forty-four patients carried HNF1A mutations, while 27 patients were found to have HNF1A polymorphisms only. Associations between mutation type/position and age at disease onset, HbAlc, body mass index (BMI), diagnosis, family history and treatment modality were analysed using non-parametric statistics (Wilcoxon test).

RESULTS

Patients with HNF1A mutations were 36% male, aged 14.1±5.8 years at diagnosis, and slightly overweight (BMI-SDS: +0.8±1.1). Treatment was lifestyle intervention (20.5%), insulin (35.3%), oral anti-diabetic (OAD, 43%) and both insulin+OAD (15.9%). More patients with missense mutations (60%) than patients with nonsense mutations/frameshift (23.8%) did not use insulin (P=0.03). No differences were found with regard to mutation types, isoform or domain. We identified several previously undescribed mutations in the cohort including c.-158insGGGTTGG in the promoter region, G31X, E41X, Q130X, L162P, R245I, A269P, S355X, Q398X, Q473X, Q495X, E508X, P588fs-insGCCA and P588fs-delAC. Patients carrying HNF1A polymorphisms were significantly younger at diagnosis than patients with HNF1A mutations (10.9±4.2 vs 14.19±5.8 years; P=0.027), and all carried I27L, S487N and A98V (n=3).

CONCLUSION

HNF1A-MODY is the second most frequent MODY diagnosis registered in the DPV database, and previously undescribed HNF1A mutations account for about one-third of HNF1A-MODY cases. Patients with HNF1A polymorphisms documented as HNF1A-MODY were misclassified. They may have autoantibody-negative type 1B or type 2 diabetes or may have other MODY types.

Entities and frequency of neonatal diabetes: data from the diabetes documentation and quality management system (DPV)

AIMS

The aim of this study was to elucidate the entities and the frequency of neonatal diabetes mellitus (NDM) in a large representative database for paediatric diabetes patients in Germany and Austria.

METHODS

Based on the continuous diabetes data acquisition system for prospective surveillance (DPV), which includes 51,587 patients with onset of diabetes before the age of 18 years from 299 centres in Germany and Austria, we searched for patients with onset of diabetes mellitus in the first 6 months of life.

RESULTS

Ninety patients were identified, comprising 0.17% of all paediatric cases in the DPV registry. This represented an incidence of approximately one case in 89,000 live births in Germany. A monogenic basis for NDM was established in 30 subjects (seven UPD6, 10 KCNJ11, seven ABCC8, two FOXP3, two PDX1, one INS, one EIF2AK3). Pancreatic hypoplasia or agenesis was reported in 10 patients and seven subjects were classified as having Type 1 diabetes by their centres. Transient neonatal diabetes (TNDM) accounted for approximately 10% of all cases with NDM. No aetiology was defined in 41 subjects, which may reflect incomplete genetic testing or novel genetic aetiologies.

CONCLUSION

Based on a large database, we identified a higher rate of NDM in Germany than has been reported previously. Full molecular genetic testing should be performed in all patients diagnosed before 6 months of age.

Diabetic ketoacidosis at diagnosis in Austrian children in 1989-2008: a population-based analysis

AIM

The aim of the study was to analyse the prevalence of diabetic onset ketoacidosis (DKA) during a period of 20 years (1989-2008) on a population basis in the whole of Austria.

METHODS

A prospective population-based incidence study (1989-2008) was performed. The registered data set comprised blood glucose, pH, ketonuria and clinical symptoms of DKA at manifestation. DKA was defined as pH < 7.3 and severe DKA as pH < 7.1. Time trends were estimated using linear regression models.

RESULTS

During the study period, 3331 children <15 years of age (1,797 boys and 1,534 girls) were registered with newly diagnosed type 1 diabetes. Of these, 1,238 (37.2%) presented with DKA, 855 (25.7%) had a mild and 383 (11.5%) a severe form, and one patient died at onset. DKA frequency was negatively associated with age at onset (p < 0.0001). In children <2 years the prevalence was 60%, with a higher risk for girls (70% vs 54% for boys, p < 0.05). Despite a significant increase in diabetes incidence in Austria during the observation period from 8.4 to 18.4/100,000 (p < 0.0001), no significant change in the prevalence of DKA at manifestation was observed.

CONCLUSIONS

The overall frequency of DKA in children with newly diagnosed type 1 diabetes in Austria is high and has not changed during the last 20 years despite a clear increase in the manifestation rate. In particular, children less than 2 years of age have a high risk of DKA at onset.

Birthweight and the risk of childhood-onset type 1 diabetes: a meta-analysis of observational studies using individual patient data

AIMS/HYPOTHESIS

We investigated whether children who are heavier at birth have an increased risk of type 1 diabetes.

METHODS

Relevant studies published before February 2009 were identified from literature searches using MEDLINE, Web of Science and EMBASE. Authors of all studies containing relevant data were contacted and asked to provide individual patient data or conduct pre-specified analyses. Risk estimates of type 1 diabetes by category of birthweight were calculated for each study, before and after adjustment for potential confounders.Meta-analysis techniques were then used to derive combined ORs and investigate heterogeneity between studies.

RESULTS

Data were available for 29 predominantly European studies (five cohort, 24 case-control studies), including 12,807 cases of type 1 diabetes. Overall, studies consistently demonstrated that children with birthweight from 3.5 to 4 kg had an increased risk of diabetes of 6% (OR 1.06 [95% CI 1.01-1.11]; p=0.02) and children with birthweight over 4 kg had an increased risk of 10% (OR 1.10 [95% CI 1.04-1.19]; p=0.003), compared with children weighing 3.0 to 3.5 kg at birth. This corresponded to a linear increase in diabetes risk of 3% per 500 g increase in birthweight (OR 1.03 [95% CI 1.00-1.06]; p=0.03). Adjustments for potential confounders such as gestational age, maternal age, birth order, Caesarean section, breastfeeding and maternal diabetes had little effect on these findings.

CONCLUSIONS/INTERPRETATION

Children who are heavier at birth have a significant and consistent, but relatively small increase in risk of type 1 diabetes.

Cognitive functions and glycemic control in children and adolescents with type 1 diabetes

BACKGROUND

The relationship between metabolic control and cognitive function in adolescents with type 1 diabetes (DM type 1) is not clear. We compared the quality of glycemic control (GC) and cognitive measures in adolescents with DM type 1 to find out if the quality of diabetes management is related to cognitive impairment.

METHOD

We assessed executive functions (EFs) and other neuropsychological and psychosocial variables in 70 adolescent patients with DM type 1 and 20 age-matched controls. Patients were divided into two groups according to their last hemoglobin A1c (HbA1c): acceptable (HbA1c 5.9-8.0%, mean 6.9%, 36 patients, mean age 14 years) and non-optimal (HbA1c 8.2-11.6%, mean 9.3%, 34 patients, mean age 15.6 years).

RESULTS

We found impaired EFs, mainly problems of concept formation (p=0.038), cognitive flexibility (p=0.011) and anticipation (p=0.000), in the patients with DM type 1. Both groups did not differ in intelligence, most assessed EFs and adjustment to chronic illness (Youth Self-Report; YSR). Younger patients (<15 years) were cognitively less flexible. GC was worse in older patients and in patients with longer duration of the disease. We also found significant differences between patients with diabetes and controls concerning somatic complaints, internalizing problems (Child Behavior Checklist; CBCL) and social activity (CBCL and YSR).

CONCLUSIONS

DM type 1 is associated with cognitive deficits in adolescents independent of the quality of metabolic control and the duration of the disease. These deficits are probably related to the disease, especially in patients with early-onset diabetes.

Phenotypical aspects of maturity-onset diabetes of the young (MODY diabetes) in comparison with Type 2 diabetes mellitus (T2DM) in children and adolescents: experience from a large multicentre database

AIMS

To analyse and compare clinical characteristics in young patients with maturity-onset diabetes of the young (MODY) and Type 2 diabetes mellitus (T2DM).

METHODS

We conducted an observational investigation using the DPV-Wiss database containing clinical data on 40 757 diabetic patients < 20 years of age from Germany and Austria.

RESULTS

Three hundred and thirty-nine cases were clinically categorized as MODY (0.83%); 562 patients were diagnosed as T2DM (1.4%). In 20% of cases, the diagnosis of MODY was based on clinical findings only. Of the 272 subjects where genetic testing was available, 3% did not carry mutations in the three examined MODY genes. Glucokinase-MODY was commoner than HNF1A-MODY and HNF4A-MODY. Age at diagnosis was younger in MODY patients. The body mass index of T2DM was significantly higher compared with all MODY subgroups. Macrovascular risk factors such as dyslipidaemia and hypertension were commoner in T2DM, but 23% of MODY patients had dyslipidaemia and 10% hypertension. Glycaemic control was within the therapeutic target (HbA(1c) < 7.5%) in 86% of MODY and 70% of T2DM patients.

CONCLUSIONS

The prevalence of MODY in children and adolescents in Germany and Austria is lower than that of T2DM in this age group. Dyslipidaemia and hypertension are less frequent in MODY compared with T2DM patients, but do occur.

Establishing glycaemic control with continuous subcutaneous insulin infusion in children and adolescents with type 1 diabetes: experience of the PedPump Study in 17 countries

AIMS/HYPOTHESIS

To assess the use of paediatric continuous subcutaneous infusion (CSII) under real-life conditions by analysing data recorded for up to 90 days and relating them to outcome.

METHODS

Pump programming data from patients aged 0-18 years treated with CSII in 30 centres from 16 European countries and Israel were recorded during routine clinical visits. HbA(1c) was measured centrally.

RESULTS

A total of 1,041 patients (age: 11.8 +/- 4.2 years; diabetes duration: 6.0 +/- 3.6 years; average CSII duration: 2.0 +/- 1.3 years; HbA(1c): 8.0 +/- 1.3% [means +/- SD]) participated. Glycaemic control was better in preschool (n = 142; 7.5 +/- 0.9%) and pre-adolescent (6-11 years, n = 321; 7.7 +/- 1.0%) children than in adolescent patients (12-18 years, n = 578; 8.3 +/- 1.4%). There was a significant negative correlation between HbA(1c) and daily bolus number, but not between HbA(1c) and total daily insulin dose. The use of <6.7 daily boluses was a significant predictor of an HbA(1c) level >7.5%. The incidence of severe hypoglycaemia and ketoacidosis was 6.63 and 6.26 events per 100 patient-years, respectively.

CONCLUSIONS/INTERPRETATION

This large paediatric survey of CSII shows that glycaemic targets can be frequently achieved, particularly in young children, and the incidence of acute complications is low. Adequate substitution of basal and prandial insulin is associated with a better HbA(1c).

Long-term non-surgical therapy of severe persistent congenital hyperinsulinism with glucagon

BACKGROUND

Congenital hyperinsulinism (CHI) is characterized by severe hypoglycemia caused by dysregulated insulin secretion. The long-term outcome is dependent on prevention of hypoglycemic episodes to avoid the high risk of permanent brain damage. Severe cases are usually resistant to diazoxide or nifedipine. In addition, somatostatin analogues are ineffective in a subgroup of patients to achieve stable euglycemia. In these infants the only remaining long-term option has been subtotal pancreatectomy with high risk of diabetes mellitus. Intravenous infusions of glucagon are used as immediate treatment to stabilize euglycemia in affected newborns. The rationale of this treatment comes from the observation of an increased glycogen content of the liver when glycogenolysis is inhibited by insulin.

OBJECTIVE

To review the efficacy and safety of long-term subcutaneous glucagon infusion as a potential therapeutic option for blood glucose stabilization in infants with severe CHI without the need of additional intravenous glucose or immediate surgical intervention.

METHOD

Retrospective review of 9 children with CHI who received continuous subcutaneous infusion of glucagon for weeks or months. Glucagon was added to octreotide to replace octreotide-induced suppression of endogenous glucagon secretion, thereby liberating glucose by stimulation of hepatic glycogenolysis. In 3 cases, a stabilized formulation of glucagon was used to prevent glucagon crystallization that frequently occurs in smaller volumes.

RESULTS

Introduction of glucagon allowed the reduction or discontinuation of central glucose infusion in all children studied. In 2 patients, glucagon was introduced due to recurrent hypoglycemia despite subtotal pancreatectomy. Six out of 9 children were discharged home on this treatment, which their parents were able to continue without further symptomatic hypoglycemia, convulsions or unconsciousness. In 3 children, subcutaneous glucagon was continuously administered for 1-4 years leading to stable euglycemia. However, 2 children with diffuse type still required subtotal pancreatectomy. As a possible side effect, 2 children developed erythema necrolyticum, which resolved after discontinuation of the glucagon infusion. This has been described before in glucagonoma.

CONCLUSION

In this retrospective series, combination therapy of low-dose octreotide and subcutaneous glucagon infusion has been effective in preventing hypoglycemic episodes in severe CHI. We propose this may serve as a therapeutic option in place of high rates of glucose infusion through a central venous catheter and as an alternative to subtotal pancreatectomy in diffuse type of CHI.

Caesarean section is associated with an increased risk of childhood-onset type 1 diabetes mellitus: a meta-analysis of observational studies

AIMS/HYPOTHESIS

The aim of this study was to investigate the evidence of an increased risk of childhood-onset type 1 diabetes in children born by Caesarean section by systematically reviewing the published literature and performing a meta-analysis with adjustment for recognised confounders.

METHODS

After MEDLINE, Web of Science and EMBASE searches, crude ORs and 95% CIs for type 1 diabetes in children born by Caesarean section were calculated from the data reported in each study. Authors were contacted to facilitate adjustments for potential confounders, either by supplying raw data or calculating adjusted estimates. Meta-analysis techniques were then used to derive combined ORs and to investigate heterogeneity between studies.

RESULTS

Twenty studies were identified. Overall, there was a significant increase in the risk of type 1 diabetes in children born by Caesarean section (OR 1.23, 95% CI 1.15-1.32, p < 0.001). There was little evidence of heterogeneity between studies (p = 0.54). Seventeen authors provided raw data or adjusted estimates to facilitate adjustments for potential confounders. In these studies, there was evidence of an increase in diabetes risk with greater birthweight, shorter gestation and greater maternal age. The increased risk of type 1 diabetes after Caesarean section was little altered after adjustment for gestational age, birth weight, maternal age, birth order, breast-feeding and maternal diabetes (adjusted OR 1.19, 95% CI 1.04-1.36, p = 0.01).

CONCLUSIONS/INTERPRETATION

This analysis demonstrates a 20% increase in the risk of childhood-onset type 1 diabetes after Caesarean section delivery that cannot be explained by known confounders.

Early mortality in EURODIAB population-based cohorts of type 1 diabetes diagnosed in childhood since 1989

AIMS/HYPOTHESIS

The aims of this study were to provide a contemporary picture of mortality and causes of death in Europe following a diagnosis of type 1 diabetes made before the 15th birthday, and to examine excess mortality by country for possible links to incidence level or national prosperity.

METHODS

Thirteen population-based EURODIAB registers in 12 countries followed-up 28,887 children diagnosed since 1989, either by record linkage to population registers or through contact with doctors providing care.

RESULTS

There were 141 deaths in the cohort during 219,061 person-years of follow-up compared with 69.1 deaths expected from national mortality rates, a standardised mortality ratio (SMR) of 2.0 (95% CI 1.7-2.4). The SMR varied from 0 to 4.7 between countries, but showed little relationship with the country's incidence rate or gross domestic product (US$ per capita). The SMR did not change significantly with attained age, calendar period or time since diagnosis. The female SMR (2.7; 95% CI 2.0-3.5) was greater than the male SMR (1.8; 95% CI 1.4-2.2), although absolute numbers of excess deaths were similar in the two sexes. One-third of deaths were classified as directly attributable to diabetes (many with mention of ketoacidosis) and half were unrelated to diabetes. There was a non-significant excess of accidental/violent deaths (48 observed vs 40.7 expected; SMR 1.2; 95% CI 0.9-1.6) but little excess in suicides (11 observed, 10.2 expected; SMR 1.1; 95% CI 0.5-1.9).

CONCLUSIONS/INTERPRETATION

Before the onset of late complications, significant excess mortality existed following the diagnosis of type 1 diabetes in childhood, even in recent years. Variation between countries in this excess could not be explained.

Obesity among female adolescents in Vienna, Austria-the impact of childhood weight status and ethnicity

OBJECTIVE

The objective of the study was to analyse prevalence of overweight and obesity among migrant girls in Vienna, Austria, starting at the age of 6 years up to the age of 15 years.

DESIGN

In a longitudinal study, the prevalence of overweight and obesity among migrant girls from Turkey and former Yugoslavia was documented and compared with that among Austrian girls in Vienna.

SETTING

Medical investigation of medical school authority in Viennese schools.

SAMPLE

Seven hundred and ninety girls of low socio-economic status were included in the study.

METHODS

Anthropometric data were collected at the age of 6, 10 and 15 years. Body mass was estimated by means of the body mass index (BMI), and percentile curves were used for determining the weight status.

MAIN OUTCOME MEASURE

Stature, body weight, BMI, weight status.

RESULTS

The prevalence of overweight and obesity was significantly higher among migrant girls at all age groups. The highest percentage of overweight was found among 10-year-old girls from Yugoslavia (nearly 35%) and the lowest percentage of overweight was exhibited in 6-year-old Austrian girls (20%). Being overweight or obese at the age of 6 years increased the risk of being overweight at 10 and 15 years significantly (P < 0.001). Among migrants, this risk was significantly higher than among Austrian girls (P < 0.001). Only 64.8% of Austrian girls, who were overweight/obese at the age of 6 years, were still classified as overweight at the age of 15 years. Among migrant girls, who were overweight at the age of 6 years, 72.0% (Turkish girls) and 78.3% (Yugoslavian girls) remained overweight until the age of 15 years.

CONCLUSIONS

Especially girls from former Yugoslavia but also Turkish girls exhibited high rates of overweight and obesity. Prevention should start as early as possible since overweight tends to persist from childhood into adolescence.

Beta-cell autoantibodies in children with type 2 diabetes mellitus: subgroup or misclassification?

BACKGROUND

In adults, a fraction of diabetic individuals with beta-cell autoantibodies has initially non-insulin requiring diabetes clinically appearing as type 2 diabetes mellitus (T2DM), named latent autoimmune diabetes in adulthood (LADA). The occurrence of beta-cell autoantibodies in European children and adolescents with T2DM has not been reported so far.

METHODS

The frequency of beta-cell autoantibodies (anti-GAD, anti-IA-2, and anti-ICA) was determined in 7050 diabetic children and adolescents. The type of diabetes was classified by paediatric diabetic specialists based on the clinical presentation. Children with non-insulin dependent T2DM over a one year period were studied separately.

RESULTS

A total of 6922 children were clinically classified as having type 1 diabetes (T1DM) and 128 children as having T2DM. Thirty six per cent of the children with T2DM had at least one detectable beta-cell autoantibody. These children did not differ significantly from the children with T2DM and without autoantibodies in respect of age, gender, weight status, lipids, blood pressure, C-peptide, glucose, and HbA1c at manifestation, as well as frequency of anti-thyroidal antibodies and insulin treatment during follow up. In the subgroup of the 38 children with T2DM without insulin requirement over a one year period, autoantibodies occurred in 32%. These 12 children were predominantly obese (67%), female (67%), and in the pubertal age range.

CONCLUSION

beta-cell autoantibodies were detectable in a subgroup of initially non-insulin dependent diabetic children and adolescents with the clinical appearance of T2DM. Following the terminology "latent autoimmune diabetes in adulthood (LADA)", this subgroup might be classified as "LADY" (latent autoimmune diabetes in youth).

Evaluation of different DNA sampling techniques for the application of the real-time PCR method for the quantification of cyanobacteria in water

AIMS

To evaluate different types of sample storage and DNA extraction techniques for the real-time PCR quantification of cyanobacteria in water.

METHODS AND RESULTS

Two different filter types for the cell harvest of Microcystis sp. and Planktothrix spp. that were either freeze-dried or stored frozen, and two different methods for DNA extraction were compared. DNA extraction was achieved by standard phenol-chloroform extraction or by a faster commercially available purification kit (DNeasy, QIAGEN). In general there was good agreement between the cell number equivalents of phycocyanin (PC) genotypes that were estimated using the Taq nuclease assay (TNA) between both filter types and the storing of samples. The standard DNA extraction procedure gave higher numbers of PC genotypes when compared with the DNeasy procedure. TNA results obtained from Planktothrix from natural samples extracted with the standard procedure revealed a significant correlation with the cell numbers estimated via the microscope.

CONCLUSIONS

Freeze-drying of samples gives quantifiable data. The standard DNA extraction is considered to be the most reliable and accurate, although the DNeasy procedure is useful for early warning monitoring.

SIGNIFICANCE AND IMPACT OF THE STUDY

Application of quantitative genotype analysis in cyanobacteria from freeze-dried samples collected during recent and past sampling programmes.

Thyroid autoimmunity in children with coexisting type 1 diabetes mellitus and celiac disease: a multicenter study

BACKGROUND

Children with type 1 diabetes mellitus (DM1) are more prone to developing thyroid autoimmunity (TAI); TAI also occurs more frequently in patients with celiac disease (CD).

AIM

To determine whether TAI occurs more frequently in children with coexisting DM1 and CD compared to children with DM1 only, and whether the clinical course of DM1 is influenced by concomitant TAI.

PATIENTS AND METHODS

We performed a multicenter retrospective case-control study comparing data from 84 diabetic children with CD (group 1) to 167 diabetic children without CD (group 2), matched by age at DM1 onset, duration of DM1 and center. Markers of TAI, thyroid function and HbA1c were recorded. The TAI follow-up lasted 4.9 +/- 2.8 years.

RESULTS

TAI was diagnosed in 13% of children in group 1 and 19% of children in group 2 (ns). Diabetes control was not influenced by TAI in either group.

CONCLUSIONS

Occurrence of TAI in diabetic children is not related to coexisting CD. TAI does not lead to worsening of metabolic control in children with DM1.