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)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998) and second (1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(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 -012-2571-8 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.Diabetologia (2012) 55:2142-2147 DOI 10.1007/s00125

Aims/hypothesis Against a background of a near-universally increasing incidence of childhood type 1 diabetes, recent reports from some countries suggest a slowing in this increase. Occasional reports also describe cyclical variations in incidence, with periodicities of between 4 and 6 years. Methods Age/sex-standardised incidence rates for the 0-to 14-year-old age group are reported for 26 European centres (representing 22 countries) that have registered newly diagnosed individuals in geographically defined regions for up to 25 years during the period 1989-2013. Poisson regression was used to estimate rates of increase and test for cyclical patterns. Joinpoint regression software was used to fit segmented log-linear relationships to incidence trends. Results Significant increases in incidence were noted in all but two small centres, with a maximum rate of increase of 6.6% per annum in a Polish centre. Several centres in high-incidence countries showed reducing rates of increase in more recent years. Despite this, a pooled analysis across all centres revealed a 3.4% (95% CI 2.8%, 3.9%) per annum increase in incidence rate, although there was some suggestion of a reduced rate of increase in the 2004-2008 period. Rates of increase were similar in boys and girls in the 0-to 4-year-old age group (3.7% and 3.7% per annum, respectively) and in the 5-to 9-year-old age group (3.4% and 3.7% per annum, respectively), but were higher in boys than girls in the 10-to 14-year-old age group (3.3% and 2.6% per annum, respectively). Significant 4 year periodicity was detected in four centres, with three centres showing that the most recent peak in fitted rates occurred in 2012. Conclusions/interpretation Despite reductions in the rate of increase in some high-risk countries, the pooled estimate across centres continues to show a 3.4% increase per annum in incidence rate, suggesting a doubling in incidence rate within approximately 20 years in Europe. Although four centres showed support for a cyclical pattern of incidence with a 4 year periodicity, no plausible explanation for this can be given.

The proportion of DKA in children with newly diagnosed diabetes mellitus is significant. In particular, children < 5 yr and girls face an increased risk. DKA may be the result of a particularly aggressive subtype of diabetes.

In a cohort of European paediatric diabetic patients, the rate of DKA was significantly higher in females and in children with migration background and early teenage years.

Objective: To investigate rates and risk factors of hospital admission for diabetic ketoacidosis (DKA) or severe hypoglycemia in young patients with established type 1 diabetes. Design: In total, 31 330 patients with type 1 diabetes (median age 12.7 years) from the Diabetes Patienten Verlaufsdokumentation (DPV) Prospective Diabetes Registry treated between 2011 and 2013 in Germany were included. Methods: Admission rates for DKA (pH !7.3 or bicarbonate !15 mmol/l) and severe hypoglycemia (requiring assistance from another person) were calculated by negative binomial regression analysis. Associations of DKA or hypoglycemia with patient and treatment characteristics were assessed by multivariable regression analysis. Results: The mean admission rate for DKA was 4.81/100 patient-years (95% CI, 4.51-5.14). The highest DKA rates were observed in patients with HbA1c R9.0% (15.83 (14.44-17.36)), age 15-20 years (6.21 (5.61-6.88)) and diabetes duration of 2-4.9 years (5.60 (5.00-6.27)). DKA rate was higher in girls than in boys (5.35 (4.88-5.86) vs 4.34 (3.95-4.77), PZ0.002), and more frequent in migrants than in non-migrants (5.65 (4.92-6.49) vs 4.57 (4.23-4.93), PZ0.008). The mean admission rate for severe hypoglycemia was 1.45/100 patient-years (1.30-1.61). Rates were higher in migrants compared to non-migrants (2.13 (1.72-2.65) vs 1.28 (1.12-1.47), P!0.001), and highest in individuals with severe hypoglycemia within the preceding year (17.69 (15.63-20.03) vs patients without preceding hypoglycemia 0.42 (0.35-0.52), P!0.001). Differences remained significant after multivariable adjustment. Conclusions: The identification of at-risk individuals for DKA (patients with high HbA1c, longer diabetes duration, adolescents, girls) and for severe hypoglycemia (patients with preceding severe hypoglycemia, migrants) may facilitate targeted diabetes counselling in order to prevent these complications.