Objective: The international SWEET registry (NCT04427189) was initiated in 2008 to improve outcomes in pediatric diabetes. A 10-year follow-up allowed studying time trends of key quality indicators in 22 centers from Europe, Australia, Canada, and India in youth with type 1 diabetes (T1D). Methods: Aggregated data per person with T1D <25 years of age were compared between 2008–2010 and 2016–2018. Hierarchic linear and logistic regression models were applied. Models were adjusted for gender, age-, and diabetes duration groups. Results: The first and second time periods included 4930 versus 13,654 persons, 51% versus 52% male, median age 11.3 [Q1; Q3: 7.9; 14.5] versus 13.3 [9.7; 16.4] years, and T1D duration 2.9 [0.8; 6.4] versus 4.2 [1.4; 7.7] years. The adjusted hemoglobin A1C (HbA1c) improved from 68 (95% confidence interval [CI]: 66–70) to 63 (60; 65) mmol/mol ( P < 0.0001) or 8.4 (95% CI: 8.2–8.6) to 7.9 (7.6; 8.1) % ( P < 0.0001). Across all age groups, HbA1c was significantly lower in pump and sensor users. Severe hypoglycemia declined from 3.8% (2.9; 5.0) to 2.4% (1.9; 3.1) ( P < 0.0001), whereas diabetic ketoacidosis events increased significantly with injection therapy only. Body mass index-standard deviation score also showed significant improvements 0.55 (0.46; 0.64) versus 0.42 (0.33; 0.51) ( P < 0.0001). Over time, the increase in pump use from 34% to 44% preceded the increase in HbA1c target achievement (<53 mmol/mol) from 21% to 34%. Conclusions: Twice yearly benchmarking within the SWEET registry was associated with significantly improved HbA1c on a background of increasing pump and sensor use for 10 years in young persons with T1D. Trial Registration: NCT04427189.

It has been proposed that unmethylated insulin promoter fragments in plasma derive exclusively from β cells, reflect their recent demise, and can be used to assess β cell damage in type 1 diabetes. Herein we describe an ultrasensitive assay for detection of a β cell–specific DNA methylation signature, by simultaneous assessment of 6 DNA methylation markers, that identifies β cell DNA in mixtures containing as little as 0.03% β cell DNA (less than 1 β cell genome equivalent). Based on this assay, plasma from nondiabetic individuals ( N = 218, aged 4–78 years) contained on average only 1 β cell genome equivalent/mL. As expected, cell-free DNA (cfDNA) from β cells was significantly elevated in islet transplant recipients shortly after transplantation. We also detected β cell cfDNA in a patient with KATP congenital hyperinsulinism, in which substantial β cell turnover is thought to occur. Strikingly, in contrast to previous reports, we observed no elevation of β cell–derived cfDNA in autoantibody-positive subjects at risk for type 1 diabetes ( N = 32), individuals with recent-onset type 1 diabetes (4 months, N = 38). We discuss the utility of sensitive β cell cfDNA analysis and potential explanations for the lack of a β cell cfDNA signal in type 1 diabetes.

Background: There are seasonal variations and gender differences in incidence of type 1 diabetes (T1D), metabolic control and responses to immune interventions at onset of the disease.We hypothesized that there are seasonal and gender differences in residual insulin secretion already at diagnosis of T1D.Methods: In 2005, a national study, the Better Diabetes Diagnosis, was started to classify all newly diagnosed children and adolescents with diabetes. About 95% (3824/4017) of the patients were classified as T1D, and our analyses are based on the patients with T1D.Results: C‐peptide was lower in younger children, 0–10 years of age (0.23 ± 0.20 nmol/L) than in older children, 11–18 years of age (0.34 ± 0.28 nmol/L) (p < 0.000 ). There was a seasonal variation in non‐fasting serum C‐peptide, significantly correlated to the seasonal variation of diagnosis (p < 0.01). Most children were diagnosed in January, February and March as well as in October when C‐peptide was highest, whereas fewer patients were diagnosed in April and May when serum C‐peptide was significantly lower (p < 0.01). The seasonal variation of C‐peptide was more pronounced in boys than in girls (p < 0.000 and p < 0.01, respectively). Girls had higher C‐peptide than boys (p < 0.05), especially in early puberty.Conclusions: Both seasonal and gender differences in residual beta cell function exist already at diagnosis of T1D. These observations have consequences for treatment and for randomizing patients in immune intervention clinical trials. Copyright © 2012 John Wiley & Sons, Ltd.