The Transatlantic HbA1c gap: differences in glycaemic control across the lifespan between people included in the US T1D Exchange Registry and those included in the German/Austrian DPV registry.

AIM: To compare HbA1c levels across the lifespan in people with type 1 diabetes in the USA with those in Germany/Austria, and to examine potential differences in HbA1c levels between sexes, insulin delivery methods and minority status. METHODS: Data were extracted from the US T1D Exchange Registry (n=18 381 participants from 73 sites) and from the German/Austrian Prospective Diabetes Follow-up Registry, the DPV (n=32 643 participants from 362 sites). Mean HbA1c was calculated for each year of age for individuals aged ≤25 years, and at 2-year age intervals for individuals aged >25 years. Curves for mean HbA1c by age were estimated using locally weighted scatterplot smoothing. HbA1c differences between registries, sexes, insulin delivery methods, and minority status were assessed by age group using multiple linear regression. RESULTS: In both registries, mean HbA1c increased by ~11 mmol/mol (1.0%) between the ages of 9 and 18 years, although at quite different absolute levels: from 66 mmol/mol (8.2%) to 77 mmol/mol (9.2%) in the T1D Exchange Registry, and from 56 mmol/mol (7.3%) to 66 mmol/mol (8.2%) in the DPV. Sex differences were observed in the DPV only. In the T1D Exchange Registry, injection users had higher mean HbA1c than pump users across the lifespan, whereas in the DPV higher HbA1c levels in injection users were observed in the age groups 6 to <12 years, 12 to <18 years, and 30 to <50 years (P < 0.001). Minority status was significantly associated with higher HbA1c in most age groups in both registries. CONCLUSIONS: Significant differences in HbA1c were noted between the USA and Germany/Austria, with disparities more pronounced in early childhood through to young adulthood. Further studies should identify causes for these disparities.

Characteristics of adult- compared to childhood-onset type 1 diabetes.

AIMS: To compare diagnosis characteristics, diabetes management and comorbidities in a population diagnosed with type 1 diabetes in childhood with those in a similar population diagnosed in adulthood to identify disease differences related to the age of diabetes onset. METHODS: This analysis was performed using the T1D Exchange Clinic Registry, a cross-sectional survivor cohort. Retrospectively collected characteristics were compared across the following age-at-diagnosis groups: <10, 10-17, 18-24, 25-39 and ≥40 years. RESULTS: The entire cohort included 20 660 participants [51% female, median (interquartile range) age 18 (14-36) years, 82% non-Hispanic white]. Diabetic ketoacidosis at diagnosis was more common among those with onset in childhood. Participants diagnosed as adults were more likely to be overweight/obese at diagnosis and to have used oral agents preceding type 1 diabetes diagnosis (57%). Current insulin pump use was less frequent in participants diagnosed at older ages. Current glycaemic control, measured by HbA1c , insulin requirements and use of a continuous glucose monitor were not different by age at diagnosis. Coeliac disease was the only comorbidity that was observed to have a different frequency by age at diagnosis, being more common in the participants diagnosed at a younger age. CONCLUSIONS: These results show differences and similarities between type 1 diabetes diagnosed in childhood vs adulthood; notably, there was a tendency for there was a higher frequency of diabetic ketoacidosis at onset in children and a higher frequency of use of oral antidiabetes agents in adults. The data indicate that there is little distinction between the clinical characteristics and outcomes of type 1 diabetes diagnosed in childhood vs adulthood. Optimizing glycaemic control remains a challenge in all age groups, with lower use of insulin pumps impacting those diagnosed as adults.

Autism spectrum disorder in children with Type 1 diabetes.

AIM: Links between autism spectrum disorder (ASD) and autoimmune diseases, including Type 1 diabetes have been proposed. This study assessed the frequency of ASD in children with Type 1 diabetes in the T1D Exchange (T1DX) registry and the impact of ASD on characteristics of children with Type 1 diabetes. METHODS: Analysis included 10 032 participants aged < 18 years (median Type 1 diabetes duration 6.5 years, 48% female, 77% non-Hispanic White). Diagnosis of ASD was defined as autism, Asperger's or pervasive developmental disorder. RESULTS: A diagnosis of ASD was recorded for 159 (1.58%) participants. Those with ASD were predominantly male (88% vs. 51% of those without ASD, P < 0.001) and slightly older (median 14 vs. 13 years, P = 0.022). Occurrence of diabetic ketoacidosis at Type 1 diabetes diagnosis was similar (35% vs. 41%, P = 0.161). Pump use was lower in those with ASD (51% vs. 63%, P = 0.005) but continuous glucose monitor use was similar (24% vs. 27%, P = 0.351). Median HbA1c was slightly lower in those with ASD [68 vs. 69 mmol/mol (8.4% vs. 8.5%), P = 0.006]. This difference was more pronounced after adjusting for confounders. CONCLUSIONS: The frequency of ASD in the T1DX registry was similar to that in the general population. These data show that despite deficits in communication, occurrence of diabetic ketoacidosis was similar in youth with and without ASD. Pump use was less frequent in those with ASD, possibly due to sensory issues, although CGM use did not differ. The lower HbA1c may be due to a more regimented routine with ASD. Because comorbidities such as ASD complicate care of patients with Type 1 diabetes, further research is needed to support these children.