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

OBJECTIVE -It is unclear whether the demands of good metabolic control or the consequences of poor control have a greater influence on quality of life (QOL) for adolescents with diabetes. This study aimed to assess these relations in a large international cohort of adolescents with diabetes and their families.RESEARCH DESIGN AND METHODS -The study involved 2,101 adolescents, aged 10 -18 years, from 21 centers in 17 countries in Europe, Japan, and North America. Clinical and demographic data were collected from March through August 1998. HbA 1c was analyzed centrally (normal range 4.4 -6.3%; mean 5.4%). Adolescent QOL was assessed by a previously developed Diabetes Quality of Life (DQOL) questionnaire for adolescents, measuring the impact of diabetes, worries about diabetes, satisfaction with life, and health perception. Parents and health professionals assessed family burden using newly constructed questionnaires.RESULTS -Mean HbA 1c was 8.7% (range 4.8 -17.4). Lower HbA 1c was associated with lower impact (P Ͻ 0.0001), fewer worries (P Ͻ 0.05), greater satisfaction (P Ͻ 0.0001), and better health perception (P Ͻ 0.0001) for adolescents. Girls showed increased worries (P Ͻ 0.01), less satisfaction, and poorer health perception (P Ͻ 0.01) earlier than boys. Parent and health professional perceptions of burden decreased with age of adolescent (P Ͻ 0.0001).Patients from ethnic minorities had poorer scores for impact (P Ͻ 0.0001), worries (P Ͻ 0.05), and health perception (P Ͻ 0.01). There was no correlation between adolescent and parent or between adolescent and professional scores.CONCLUSIONS -In a multiple regression model, lower HbA 1c was significantly associated with better adolescent-rated QOL on all four subscales and with lower perceived family burden as assessed by parents and health professionals.

Improvements in the prevention or control of rejection of the kidney and liver have been largely interchangeable (1,2) and then applicable, with very little modification, to thoracic and other organs. However, the mechanism by which anti rejection treatment permits any of these grafts to be "accepted" has been an immunological enigma (3,4). We have proposed recently that the exchange of migratory leukocytes between the transplant and the recipient with consequent long-term cellular chimerism in both is the basis for acceptance of all whole-organ allografts and xenografts (5). Although such chimerism was demonstrated only a few months ago, the observations have increased our insight into transplantation immunology and have encouraged the development of alternative therapeutic strategies (6). DISCOVERY OF GRAFT CHIMERISM After Liver TransplantationSuccessful transplants were long envisioned as an alien patch in a homogeneous host (Fig. 1, left). The first unequivocal evidence that whole-organ grafts in human beings become genetic composites (chimeras) was obtained in 1969 with karyotyping studies in female recipients of livers obtained from male cadaveric donors. Postoperatively, the hepatocytes and the endothelium of the major blood vessels of the grafts retained their donor sex, whereas the entire macrophage system, including the Kupffer cells, was replaced with recipient female cells (identified by their characteristic Barr bodies) within 100 days (7,8) (Fig. 1, middle). These observations attracted considerable attention at the time, primarily because of their implication that liver-based inborn errors of metabolism could be corrected permanently by liver replacement (9,10). This prediction has been met since then in nearly two dozen such heritable diseases (11). Each report of another liver-based metabolic disorder that was corrected by liver replacement added to the illusion that the composite (chimeric) structure of the hepatic allograft was a special feature of this organ.Address reprint requests to: Thomas E. Starzl, M.D., Ph.D., Department of Surgery, 3601 Fifth Avenue, 5C Falk Clinic, University of Pittsburgh, Pittsburgh, PA, 15213. NIH Public Access Author ManuscriptHepatology. Author manuscript; available in PMC 2010 October 26. Published in final edited form as:Hepatology. 1993 June ; 17(6): 1127-1152. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript After Intestinal TransplantationThe illusion of uniqueness of the hepatic graft was dispelled in 1991 with the demonstration, first in rat models (12) and then in human beings (13), that all successfully transplanted intestines also were chimeric. The epithelium of the bowel remained that of the donor, but lymphoid, dendritic and other leukocytes of recipient phenotype quickly became the dominant cells in the lamina propria, Peyer's patches and mesenteric nodes. The transformation in experimental animals and in human beings (Fig, 2) was the same whether the bowel was transplanted alone or as a part of a multivisceral gra...

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.

OBJECTIVE -To reevaluate the persistence and stability of previously observed differences between pediatric diabetes centers and to investigate the influence of demography, language communication problems, and changes in insulin regimens on metabolic outcome, hypoglycemia, and ketoacidosis. RESULTS -Mean A1C was 8.2 Ϯ 1.4%, with substantial variation between centers (mean A1C range 7.4 -9.2%; P Ͻ 0.001). There were no significant differences between centers in rates of severe hypoglycemia or diabetic ketoacidosis. Language difficulties had a significant negative impact on metabolic outcome (A1C 8.5 Ϯ 2.0% vs. 8.2 Ϯ 1.4% for those with language difficulties vs. those without, respectively; P Ͻ 0.05). After adjustement for significant confounders of age, sex, duration of diabetes, insulin regimen, insulin dose, BMI, and language difficulties, the center differences persisted, and the effect size for center was not reduced. Relative center ranking since 1998 has remained stable, with no significant change in A1C. RESEARCH DESIGN AND METHODSCONCLUSIONS -Despite many changes in diabetes management, major differences in metabolic outcome between 21 international pediatric diabetes centers persist. Different application between centers in the implementation of insulin treatment appears to be of more importance and needs further exploration.

OBJECTIVE -Twenty-one international pediatric diabetes centers from 17 countries investigated the effect of simple feedback about the grand mean HbA 1c level of all centers and the average value of each center on changes in metabolic control, rate of severe hypoglycemia, and insulin therapy over a 3-year period.RESEARCH DESIGN AND METHODS -Clinical data collection and determination of HbA 1c levels were conducted at a central location in 1995 (n ϭ 2,780, age 0 -18 years) and 1998 (n ϭ 2,101, age 11-18 years).RESULTS -Striking differences in average HbA 1c concentrations were found among centers; these differences remained after adjustment for the significant confounders of sex, age, and diabetes duration. They were apparent even in patients with short diabetes duration and remained stable 3 years later (mean adjusted HbA 1c level: 8.62 Ϯ 0.03 vs. 8.67 Ϯ 0.04 [1995 vs. 1998, respectively]). Three centers had improved significantly, four centers had deteriorated significantly in their overall adjusted HbA 1c levels, and 14 centers had not changed in glycemic control. During the observation period, there were increases in the adjusted insulin dose by 0.076 U/kg, the adjusted number of injections by 0.23 injections per day, and the adjusted BMI by 0.95 kg/m 2 . The 1995 versus 1998 difference in glycemic control for the seven centers could not be explained by prevailing insulin regimens or rates of hypoglycemia.CONCLUSIONS -This study reveals significant outcome differences among large international pediatric diabetes centers. Feedback and comparison of HbA 1c levels led to an intensification of insulin therapy in most centers, but improved glycemic control in only a few.

We have previously reported data from clinical and laboratory animal observations which suggest that organ tolerance after transplantation depends on a state of balanced lymphodendritic cell chimerism between the host and donor graft. We have sought further evidence to support this hypothesis by investigating HLA-mismatched liver allograft recipients. 9 of 9 female recipients of livers from male donors had chimerism in their allografts and extrahepatic tissues, according to in-situ hybridisation and molecular techniques 10 to 19 years posttransplantation. In 8 women with good graft function, evidence of the Y chromosome was found in the blood (6/8), skin (8/8), and lymph nodes (7/8). A ninth patient whose transplant failed after 12 years from recurrent chronic viral hepatitis had chimerism in her lymph nodes, skin, jejunum, and aorta at the time of retransplantation. Although cell migration is thought to take place after all types of transplantation, the large population of migratory cells in, and the extent of their seeding from, hepatic grafts may explain the privileged tolerogenicity of the liver compared with other organs.

Family factors, particularly dynamic and communication factors such as parental over-involvement and adolescent-parent concordance on responsibility for diabetes care appear be important determinants of metabolic outcomes in adolescents with diabetes. However, family dynamic factors do not account for the substantial differences in metabolic outcomes between centres.