International benchmarking in type 1 diabetes: Large difference in childhood HbA1c between eight high-income countries but similar rise during adolescence-A quality registry study.

OBJECTIVES: To identify differences and similarities in HbA1c levels and patterns regarding age and gender in eight high-income countries. SUBJECTS: 66 071 children and adolescents below18 years of age with type 1 diabetes for at least 3 months and at least one HbA1c measurement during the study period. METHODS: Pediatric Diabetes Quality Registry data from Austria, Denmark, England, Germany, Norway, Sweden, the United States, and Wales were collected between 2013 and 2014. HbA1c, gender, age, and duration were used in the analysis. RESULTS: Distribution of gender and age groups was similar in the eight participating countries. The mean HbA1c varied from 60 to 73 mmol/mol (7.6%-8.8%) between the countries. The increase in HbA1c between the youngest (0-9 years) to the oldest (15-17 years) age group was close to 8 mmol/mol (0.7%) in all countries (P < .001). Females had a 1 mmol/mol (0.1%) higher mean HbA1c than boys (P < .001) in seven out of eight countries. CONCLUSIONS: In spite of large differences in the mean HbA1c between countries, a remarkable similarity in the increase of HbA1c from childhood to adolescence was found.

Continuous glucose monitoring and glycemic control among youth with type 1 diabetes: International comparison from the T1D Exchange and DPV Initiative.

BACKGROUND: To assess the change in rates of pediatric real-time or intermittent scanning continuous glucose monitoring (CGM) use over the past 5 years, and how it impacts glycemic control, data from two registries were compared: the US-based type 1 diabetes Exchange Registry (T1DX) and the German/Austrian DPV (Prospective Diabetes Follow-Up Registry). METHODS: Registry participants aged <18 years with T1D duration ≥1 year encompassed 29 007 individuals in 2011 and 29 150 participants in 2016. Demographic data, CGM use and hemoglobin A1c (HbA1c) were obtained from medical records. RESULTS: CGM use increased from 2011 to 2016 in both registries across all age groups, regardless of gender, ethnic minority status or insulin delivery method. The increase in CGM use was most pronounced in the youngest patients, and usage rates remain lowest for adolescent patients in 2016. For both registries in 2016, mean HbA1c was lower among CGM users regardless of insulin delivery method compared to pump only (P < 0.001) and injection only (P < 0.001), and CGM users were more likely to achieve glycemic target of HbA1c <7.5% (56% vs 43% for DPV and 30% vs 15% for T1DX, P < 0.001). T1DX participants had a higher mean HbA1c compared with DPV despite whether they were CGM users or non-users; however, the difference was less pronounced in CGM users (P < 0.001). CONCLUSIONS: Pediatric CGM use increased in both registries and was associated with lower mean HbA1c regardless of insulin delivery modality.

Association of individual and area-level socioeconomic conditions with quality of life and glycaemic control in 11- to 21-year-old adolescents with early-onset type 1 diabetes: a cross-sectional study.

PURPOSE: To analyse the association of area-level deprivation (German Index of Multiple Deprivation, GIMD 2010) with health- and disease-related quality of life (QoL) and glycaemic control (HbA1c) jointly with individual-level socioeconomic status (SES) in young patients with preschool-onset type 1 diabetes. METHODS: A total of 425 male and 414 female patients aged 11-21 years from a Germany-wide population-based survey completed the generic KINDL-R, the DISABKIDS chronic-generic module (DCGM-12), and the DISABKIDS diabetes-specific module with impact and treatment scales (QoL indicators; range 0-100 with higher scores representing better QoL). To analyse the association of area-level deprivation and SES with QoL and HbA1c, multiple linear regression models were applied adjusting for sociodemographic and health-related variables. RESULTS: Mean QoL scores (SD) were 73.2 (12.2) for the KINDL-R, 76.1 (16.1) for the DCGM-12, 66.2 (19.9) for diabetes impact, and 56.4 (27.3) for diabetes treatment (DISABKIDS). Mean HbA1c was 8.3 (1.4)%. While both QoL outcomes and HbA1c level improved with increasing individual SES, no association was observed between area-level deprivation (GIMD 2010) and either outcome. CONCLUSIONS: Compared with individual SES, area-level deprivation seems to be of minor importance for QoL and glycaemic control in young people with early-onset type 1 diabetes.

Self-reported regular alcohol consumption in adolescents and emerging adults with type 1 diabetes: A neglected risk factor for diabetic ketoacidosis? Multicenter analysis of 29 630 patients from the DPV registry.

BACKGROUND: The risk of hypoglycemia increases after alcohol consumption in patients with type 1 diabetes. This study aimed to investigate the association between metabolic control and self-reported alcohol consumption in young patients with type 1 diabetes. MATERIALS AND METHODS: N = 29 630 patients with type 1 diabetes aged 12 to <30 years (median age 17.0 [14.9, 18.3] years, duration of diabetes 6.8 [3.3, 10.9] years, 53% male) from the German/Austrian DPV registry were analyzed. Patients were categorized into abstainers, low-risk drinkers, and at-risk drinkers. BMI, HbA1c, and rates of severe hypoglycemia (SH) and diabetic ketoacidosis (DKA) were compared between alcohol consumption groups using multivariable hierarchical regression models. The association between alcohol use and smoking status was assessed using χ 2 test. RESULTS: Overall, 10.8% of the patients reported regular alcohol consumption. Proportion of alcohol use as well as the amount of alcohol consumed increased with age and were higher in males than in females (all P < .05). Patients with Turkish migration background reported less alcohol consumption. HbA1c, SH rate, and DKA rate (adjusted for age, gender, duration of diabetes, therapy) were significantly lower in abstainers than in patients drinking alcohol (all P < .05). Smoking status was significantly associated with alcohol consumption (P < .001). CONCLUSION: Self-reported alcohol consumption is likely to be underreported when collected in face-to-face settings such as doctors' visits. Nevertheless, our data revealed a significant association between higher alcohol consumption and worse glycemic control, in particular higher DKA rates. Information about alcohol-induced complications is of great importance in diabetes education in young people with type 1 diabetes.

Factors contributing to partial remission in type 1 diabetes: analysis based on the insulin dose-adjusted HbA1c in 3657 children and adolescents from Germany and Austria.

OBJECTIVE: Insulin dose-adjusted hemoglobin A1c (HbA1C, IDAA1c) correlates well with stimulated C-peptide levels, but has not yet been evaluated in a large cohort of patients with Type 1 diabetes (T1D). METHODS: We investigated prevalence of partial remission (PREM) defined by IDAA1c ≤9 in 3657 in children with new-onset T1D who were continuously followed over 6 years. We evaluated the predictors of PREM using the multicenter database from the DPV (Diabetes Patienten Verlaufsdokumentation) registry. RESULTS: PREM occurred in 71% of patients. Median duration was 9 (0-21) months. Compared to children <5 years at T1D onset, those aged 5-10 and ≥10 years had twice the chance of developing PREM (OR: 2.08, CI: 1.67-2.60; P < .001 and OR: 2.16, CI: 1.70-2.75; P < .001). Boys were more likely to develop PREM than girls (OR 1.41, CI: 1.18-1.69; P = .0002). Further predictors for PREM were: ketoacidosis, autoantibodies, and HbA1c at T1D onset. These results were confirmed by quantile regression analysis with duration of PREM as dependent variable. CONCLUSION: This research on a large cohort provides insight into epidemiologic characteristics of PREM in T1D defined by IDAA1c. As IDAA1c does not discriminate between insulin sensitivity and secretion, available data cannot resolve whether the sex-difference in PREM reflects innate higher insulin resistance in girls, or better beta-cell recovery in boys. Further research is needed to clarify the usefulness and performance of IDAA1c in clinical practice.

Severe hypoglycemia rates are not associated with HbA1c: a cross-sectional analysis of 3 contemporary pediatric diabetes registry databases.

OBJECTIVE: To examine the association between glycated hemoglobin (HbA1c) and severe hypoglycemia rates in patients with type 1 diabetes receiving usual care, by analysing data from the US Type 1 Diabetes Exchange (T1DX), German/Austrian Diabetes Patienten Verlaufsdokumenation (DPV), and Western Australian Children Diabetes Database (WACDD) diabetes registries. METHODS: Data for patients with type 1 diabetes, aged <18 years with a minimum duration of diabetes of 2 years, were extracted from each registry for a 12-month observation period between 2011 and 2012 (7,102 T1DX, 18,887 DPV, and 865 WACDD). Rates of severe hypoglycemia (self-reported loss of consciousness/convulsion) were estimated per 100 patient-years and analyzed by HbA1c, source registry, treatment regimen, and age group. RESULTS: Overall, the severe hypoglycemia rate per 100 patient years was 7.1, 3.3, and 6.7 in T1DX, DPV, and WACDD patients, respectively. Lower HbA1c was not associated with an increased rate of severe hypoglycemia when examined by source registry, treatment regimen, or age group. CONCLUSION: An inverse relationship between mean HbA1c and risk of severe hypoglycemia was not observed in this study of 3, independent cohorts of children and adolescents with type 1 diabetes. Investigation in other large, longitudinal cohorts is recommended to further characterize the contemporary relationship between glycemic control and risk of severe hypoglycemia rates in pediatric patients with type 1 diabetes.

Use of insulin pump therapy in children and adolescents with type 1 diabetes and its impact on metabolic control: comparison of results from three large, transatlantic paediatric registries.

AIMS/HYPOTHESIS: While the use of insulin pumps in paediatrics has expanded dramatically, there is still considerable variability among countries in the use of pump technology. The present study sought to describe differences in metabolic control and pump use in young people with type 1 diabetes using data collected in three multicentre registries. METHODS: Data for the years 2011 and 2012 from 54,410 children and adolescents were collected from the Prospective Diabetes Follow-up Registry (DPV; n = 26,198), T1D Exchange (T1DX; n = 13,755) and the National Paediatric Diabetes Audit (NPDA; n = 14,457). The modality of insulin delivery, based on age, sex and ethnic minority status, and the impact of pump use on HbA1c levels were compared. RESULTS: The overall mean HbA1c level was higher in the NPDA (8.9 ± 1.6% [74 ± 17.5 mmol/mol]) than in the DPV (8.0 ± 1.6% [64 ± 17.0 mmol/mol], p < 0.001) and T1DX (8.3 ± 1.4% [68 ± 15.4 mmol/mol], p < 0.001). Conversely, pump use was much lower in the NPDA (14%) than in the DPV (41%, p < 0.001) and T1DX (47%, p < 0.001). In a pooled analysis, pump use was associated with a lower mean HbA1c (pump: 8.0 ± 1.2% [64 ± 13.3 mmol/mol] vs injection: 8.5 ± 1.7% [69 ± 18.7 mmol/mol], p < 0.001). In all three registries, those with an ethnic minority status were less likely to be treated with a pump (p < 0.001) and boys were treated with a pump less often compared with girls (p < 0.001). CONCLUSIONS/INTERPRETATION: Despite similar clinical characteristics and proportion of minority participants, substantial differences in metabolic control exist across the three large transatlantic registries of paediatric patients with type 1 diabetes, which appears to be due in part to the frequency of insulin pump therapy.

Obesity in Youth with Type 1 Diabetes in Germany, Austria, and the United States.

OBJECTIVE: To examine the current extent of the obesity problem in 2 large pediatric clinical registries in the US and Europe and to examine the hypotheses that increased body mass index (BMI) z-scores (BMIz) are associated with greater hemoglobin A1c (HbA1c) and increased frequency of severe hypoglycemia in youth with type 1 diabetes (T1D). STUDY DESIGN: International (World Health Organization) and national (Centers for Disease Control and Prevention/German Health Interview and Examination Survey for Children and Adolescents) BMI references were used to calculate BMIz in participants (age 2-<18 years and ≥ 1 year duration of T1D) enrolled in the T1D Exchange (n = 11,435) and the Diabetes Prospective Follow-up (n = 21,501). Associations between BMIz and HbA1c and severe hypoglycemia were assessed. RESULTS: Participants in both registries had median BMI values that were greater than international and their respective national reference values. BMIz was significantly greater in the T1D Exchange vs the Diabetes Prospective Follow-up (P < .001). After stratification by age-group, no differences in BMI between registries existed for children 2-5 years, but differences were confirmed for 6- to 9-, 10- to 13-, and 14- to 17-year age groups (all P < .001). Greater BMIz were significantly related to greater HbA1c levels and more frequent occurrence of severe hypoglycemia across the registries, although these associations may not be clinically relevant. CONCLUSIONS: Excessive weight is a common problem in children with T1D in Germany and Austria and, especially, in the US. Our data suggest that obesity contributes to the challenges in achieving optimal glycemic control in children and adolescents with T1D.

Contrasting the clinical care and outcomes of 2,622 children with type 1 diabetes less than 6 years of age in the United States T1D Exchange and German/Austrian DPV registries.

AIMS/HYPOTHESIS: The study aimed to compare participant characteristics, treatment modalities and clinical outcomes in registry participants less than 6 years old. METHODS: Participant characteristics, treatment modalities and clinical outcomes (HbA1c, severe hypoglycaemia [SH] and diabetic ketoacidosis [DKA]) as well as frequencies of attaining HbA1c goals in line with the International Society for Pediatric and Adolescent Diabetes (<7.5% [<58 mmol/mol]) and ADA (<8.5% [<69 mmol/mol]) were compared. RESULTS: Insulin pump use was more frequent (74% vs 50%, p < 0.001) and HbA1c levels lower in the Prospective Diabetes Follow-up Registry (DPV) than in the T1D Exchange (T1DX) (mean 7.4% vs 8.2%, p < 0.001). A lower HbA1c level was seen in the DPV compared with the T1DX for both pump users (p < 0.001) and injection users (p < 0.001). More children from DPV were meeting the recommended HbA1c goals, compared with children from T1DX (HbA1c <7.5%: 56% vs 22%, p < 0.001; HbA1c <8.5%: 90% vs 66%, p < 0.001). The adjusted odds of having an HbA1c level <7.5% or <8.5% were 4.2 (p < 0.001) and 3.6 (p < 0.001) higher for the DPV than the T1DX, respectively. The frequency of SH did not differ between registries or by HbA1c, whereas the frequency of DKA was higher for the T1DX and greater in those with higher HbA1c levels. CONCLUSIONS/INTERPRETATION: DPV data indicate that an HbA1c of <7.5% can frequently be achieved in children with type 1 diabetes who are under 6 years old. An improved metabolic control of type 1 diabetes in young patients appears to decrease the risk of DKA without increasing SH. The greater frequency of suboptimal control in young patients in the T1DX compared with the DPV is not fully explained by a less frequent use of insulin pumps and may relate to the higher HbA1c targets that are recommended for this age group in the USA.

The guidance and adhesion protein FLRT2 dimerizes in cis via dual small-X3-small transmembrane motifs.

Fibronectin Leucine-rich Repeat Transmembrane (FLRT 1-3) proteins are a family of broadly expressed single-spanning transmembrane receptors that play key roles in development. Their extracellular domains mediate homotypic cell-cell adhesion and heterotypic protein interactions with other receptors to regulate cell adhesion and guidance. These in trans FLRT interactions determine the formation of signaling complexes of varying complexity and function. Whether FLRTs also interact at the surface of the same cell, in cis, remains unknown. Here, molecular dynamics simulations reveal two dimerization motifs in the FLRT2 transmembrane helix. Single particle tracking experiments show that these Small-X3-Small motifs synergize with a third dimerization motif encoded in the extracellular domain to permit the cis association and co-diffusion patterns of FLRT2 receptors on cells. These results may point to a competitive switching mechanism between in cis and in trans interactions, which suggests that homotypic FLRT interaction mirrors the functionalities of classic adhesion molecules.

An mTORC1 to HRI signaling axis promotes cytotoxicity of proteasome inhibitors in multiple myeloma.

Multiple myeloma (MM) causes approximately 20% of deaths from blood cancers. Notwithstanding significant therapeutic progress, such as with proteasome inhibitors (PIs), MM remains incurable due to the development of resistance. mTORC1 is a key metabolic regulator, which frequently becomes dysregulated in cancer. While mTORC1 inhibitors reduce MM viability and synergize with other therapies in vitro, clinically, mTORC1 inhibitors are not effective for MM. Here we show that the inactivation of mTORC1 is an intrinsic response of MM to PI treatment. Genetically enforced hyperactivation of mTORC1 in MM was sufficient to compromise tumorigenicity in mice. In vitro, mTORC1-hyperactivated MM cells gained sensitivity to PIs and hypoxia. This was accompanied by increased mitochondrial stress and activation of the eIF2α kinase HRI, which initiates the integrated stress response. Deletion of HRI elevated the toxicity of PIs in wt and mTORC1-activated MM. Finally, we identified the drug PMA as a robust inducer of mTORC1 activity, which synergized with PIs in inducing MM cell death. These results help explain the clinical inefficacy of mTORC1 inhibitors in MM. Our data implicate mTORC1 induction and/or HRI inhibition as pharmacological strategies to enhance MM therapy by PIs.

Children with onset-ketoacidosis are admitted to the nearest hospital available, regardless of center size.

Background To investigate longitudinal trends of admissions with diabetic ketoacidosis (DKA) in new-onset type 1 diabetes (T1D) and subsequent duration of hospitalization in association with structural health care properties, such as size of treatment facility, population density and linear distance between home and treatment centers. Methods Data from 24,321 German and Austrian pediatric patients with newly-diagnosed T1D between 2008 and 2017 within the DPV registry were analyzed. Results Onset-DKA rates fluctuated at around 19% and slightly increased over the observation period (p<0.001). Compared to children without onset-DKA, children with onset-DKA were more frequently treated at centers located closer to their homes, independent of center size or urbanity. Annual median duration of hospitalization decreased from 13.1 (12.6;13.6) to 12.7 (12.3;13.2) days (p<0.001). It was highest in patients younger than 5 years, with migration background, and in severe DKA. Conclusion Patients with onset-DKA are admitted to the nearest hospital, independent of center size. Facilities close to patients' homes therefore play an important role in the acute management of T1D onset. In Germany and Austria, diabetes education at diagnosis is mainly performed in inpatient settings. This is reflected by a long duration of hospitalization, which has decreased only slightly over the past decade.

Contribution of NAADP to Glutamate-Evoked Changes in Ca2+ Homeostasis in Mouse Hippocampal Neurons.

Nicotinic acid adenine dinucleotide phosphate (NAADP) is a second messenger that evokes calcium release from intracellular organelles by the engagement of calcium release channels, including members of the Transient Receptor Potential (TRP) family, such as TRPML1, the (structurally) related Two Pore Channel type 1 (TPC1) and TPC2 channels as well as Ryanodine Receptors type 1 (RYR1; Guse, 2012). NAADP evokes calcium release from acidic calcium stores of many cell types (Guse, 2012), and NAADP-sensitive Ca2+ stores have been described in hippocampal neurons of the rat (Bak et al., 1999; McGuinness et al., 2007). Glutamate triggers Ca2+-mediated neuronal excitotoxicity in inflammation-induced neurodegenerative pathologies such as Multiple Sclerosis (MS; Friese et al., 2014), and when applied extracellularly to neurons glutamate can elevate NAADP levels in these cells. Accordingly, glutamate-evoked Ca2+ signals from intracellular organelles were inhibited by preventing organelle acidification (Pandey et al., 2009). Analysis of reported RNA sequencing experiments of cultured hippocampal neurons revealed the abundance of Mcoln1 (encoding TRPML1), Tpcn1, and Tpcn2 (encoding TPC1 and TPC2, respectively) as potential NAADP target channels in these cells. Transcripts encoding Ryr1 were not found in contrast to Ryr2 and Ryr3. To study the contribution of NAADP signaling to glutamate-evoked calcium transients in murine hippocampal neurons we used the NAADP antagonists Ned-19 (Naylor et al., 2009) and BZ194 (Dammermann et al., 2009). Our results show that both NAADP antagonists significantly reduce glutamate-evoked calcium transients. In addition to extracellular glutamate application, we studied synchronized calcium oscillations in the cells of the neuronal cultures evoked by addition of the GABAA receptor antagonist bicuculline. Pretreatment with Ned-19 (50 µM) or BZ194 (100 µM) led to an increase in the frequency of bicuculline-induced calcium oscillations at the cost of calcium transient amplitudes. Interestingly, Ned-19 triggered a rise in intracellular calcium concentrations 25 min after bicuculline stimulation, leading to the question whether NAADP acts as a neuroprotective messenger in hippocampal neurons. Taken together, our results are in agreement with the concept that NAADP signaling significantly contributes to glutamate evoked Ca2+ rise in hippocampal neurons and to the amplitude and frequency of synchronized Ca2+ oscillations triggered by spontaneous glutamate release events.

A Painless Right Anterior Neck Mass.

A 58-year-old woman presents with a several-week history of a painless right-sided swelling on her anterior neck. What is your diagnosis?

Decreasing Trends in Mean HbA1c Are Not Associated With Increasing Rates of Severe Hypoglycemia in Children: A Longitudinal Analysis of Two Contemporary Population-Based Pediatric Type 1 Diabetes Registries From Australia and Germany/Austria Between 1995 and 2016.

OBJECTIVE: To investigate temporal trends in glycemic control and severe hypoglycemia rates for pediatric patients with type 1 diabetes from 1995 to 2016 by analyzing data from the longitudinal, prospective, population-based German/Austrian (Diabetes Patient History Documentation [DPV]) and Western Australian (Western Australian Children's Diabetes Database [WACDD]) diabetes registries. RESEARCH DESIGN AND METHODS: Patients diagnosed with type 1 diabetes aged <15 years were identified from the DPV (N = 59,883) and WACDD (N = 2,595) registries and data extracted for all clinic visits occurring between 1995 and 2016, inclusive. Mean HbA1c and severe hypoglycemia (self-reported loss of consciousness/convulsion) rates were calculated per 100 patient-years. RESULTS: Between 1995 and 2016, the annual mean HbA1c decreased from 8.3 to 7.8% in the DPV cohort and from 9.2 to 8.3% in the WACDD cohort. Over the same period, the severe hypoglycemia rate decreased by an annual average of 2% (relative risk 0.983 [95% CI 0.981, 0.986]) in the DPV cohort and 6% (relative risk 0.935 [95% CI 0.934, 0.937]) in the WACDD cohort. Concomitant decreasing trends in both HbA1c and severe hypoglycemia rates were observed in boys and girls, all age-groups, and injection therapy/pump regimen groups. CONCLUSIONS: Over the past two decades, there have been concurrent improvements in HbA1c and decreasing severe hypoglycemia rates in two contemporary, longitudinal, population-based pediatric cohorts of type 1 diabetes. Translation of these data into clinical practice and patient education may reduce fear of hypoglycemia and enable better glycemic control.

Resilience and restoration of tropical and subtropical grasslands, savannas, and grassy woodlands.

Despite growing recognition of the conservation values of grassy biomes, our understanding of how to maintain and restore biodiverse tropical grasslands (including savannas and open-canopy grassy woodlands) remains limited. To incorporate grasslands into large-scale restoration efforts, we synthesised existing ecological knowledge of tropical grassland resilience and approaches to plant community restoration. Tropical grassland plant communities are resilient to, and often dependent on, the endogenous disturbances with which they evolved - frequent fires and native megafaunal herbivory. In stark contrast, tropical grasslands are extremely vulnerable to human-caused exogenous disturbances, particularly those that alter soils and destroy belowground biomass (e.g. tillage agriculture, surface mining); tropical grassland restoration after severe soil disturbances is expensive and rarely achieves management targets. Where grasslands have been degraded by altered disturbance regimes (e.g. fire exclusion), exotic plant invasions, or afforestation, restoration efforts can recreate vegetation structure (i.e. historical tree density and herbaceous ground cover), but species-diverse plant communities, including endemic species, are slow to recover. Complicating plant-community restoration efforts, many tropical grassland species, particularly those that invest in underground storage organs, are difficult to propagate and re-establish. To guide restoration decisions, we draw on the old-growth grassland concept, the novel ecosystem concept, and theory regarding tree cover along resource gradients in savannas to propose a conceptual framework that classifies tropical grasslands into three broad ecosystem states. These states are: (1) old-growth grasslands (i.e. ancient, biodiverse grassy ecosystems), where management should focus on the maintenance of disturbance regimes; (2) hybrid grasslands, where restoration should emphasise a return towards the old-growth state; and (3) novel ecosystems, where the magnitude of environmental change (i.e. a shift to an alternative ecosystem state) or the socioecological context preclude a return to historical conditions.

Comment on "The global tree restoration potential".

Bastin et al's estimate (Reports, 5 July 2019, p. 76) that tree planting for climate change mitigation could sequester 205 gigatonnes of carbon is approximately five times too large. Their analysis inflated soil organic carbon gains, failed to safeguard against warming from trees at high latitudes and elevations, and considered afforestation of savannas, grasslands, and shrublands to be restoration.

Exploring Variation in Glycemic Control Across and Within Eight High-Income Countries: A Cross-sectional Analysis of 64,666 Children and Adolescents With Type 1 Diabetes.

OBJECTIVE: International studies on childhood type 1 diabetes (T1D) have focused on whole-country mean HbA1c levels, thereby concealing potential variations within countries. We aimed to explore the variations in HbA1c across and within eight high-income countries to best inform international benchmarking and policy recommendations. RESEARCH DESIGN AND METHODS: Data were collected between 2013 and 2014 from 64,666 children with T1D who were <18 years of age across 528 centers in Germany, Austria, England, Wales, U.S., Sweden, Denmark, and Norway. We used fixed- and random-effects models adjusted for age, sex, diabetes duration, and minority status to describe differences between center means and to calculate the proportion of total variation in HbA1c levels that is attributable to between-center differences (intraclass correlation [ICC]). We also explored the association between within-center variation and children's glycemic control. RESULTS: Sweden had the lowest mean HbA1c (59 mmol/mol [7.6%]) and together with Norway and Denmark showed the lowest between-center variations (ICC ≤4%). Germany and Austria had the next lowest mean HbA1c (61-62 mmol/mol [7.7-7.8%]) but showed the largest center variations (ICC ∼15%). Centers in England, Wales, and the U.S. showed low-to-moderate variation around high mean values. In pooled analysis, differences between counties remained significant after adjustment for children characteristics and center effects (P value <0.001). Across all countries, children attending centers with more variable glycemic results had higher HbA1c levels (5.6 mmol/mol [0.5%] per 5 mmol/mol [0.5%] increase in center SD of HbA1c values of all children attending a specific center). CONCLUSIONS: At similar average levels of HbA1c, countries display different levels of center variation. The distribution of glycemic achievement within countries should be considered in developing informed policies that drive quality improvement.

Longitudinal Trajectories of Metabolic Control From Childhood to Young Adulthood in Type 1 Diabetes From a Large German/Austrian Registry: A Group-Based Modeling Approach.

OBJECTIVE: Worsening of glycemic control in type 1 diabetes during puberty is a common observation. However, HbA1c remains stable or even improves for some youths. The aim is to identify distinct patterns of glycemic control in type 1 diabetes from childhood to young adulthood. RESEARCH DESIGN AND METHODS: A total of 6,433 patients with type 1 diabetes were selected from the prospective, multicenter diabetes patient registry Diabetes-Patienten-Verlaufsdokumentation (DPV) (follow-up from age 8 to 19 years, baseline diabetes duration ≥2 years, HbA1c aggregated per year of life). We used latent class growth modeling as the trajectory approach to determine distinct subgroups following a similar trajectory for HbA1c over time. RESULTS: Five distinct longitudinal trajectories of HbA1c were determined, comprising group 1 = 40%, group 2 = 27%, group 3 = 15%, group 4 = 13%, and group 5 = 5% of patients. Groups 1-3 indicated stable glycemic control at different HbA1c levels. At baseline, similar HbA1c was observed in group 1 and group 4, but HbA1c deteriorated in group 4 from age 8 to 19 years. Similar patterns were present in group 3 and group 5. We observed differences in self-monitoring of blood glucose, insulin therapy, daily insulin dose, physical activity, BMI SD score, body-height SD score, and migration background across all HbA1c trajectories (all P ≤ 0.001). No sex differences were present. Comparing groups with similar initial HbA1c but different patterns, groups with higher HbA1c increase were characterized by lower frequency of self-monitoring of blood glucose and physical activity and reduced height (all P < 0.01). CONCLUSIONS: Using a trajectory approach, we determined five distinct longitudinal patterns of glycemic control from childhood to early adulthood. Diabetes self-care, treatment differences, and demographics were related to different HbA1c courses.