Ananth Nayak

Evidence for Consistency of the Glycation Gap in Diabetes

OBJECTIVE Discordance between HbA1c and fructosamine estimations in the assessment of glycemia is often encountered. A number of mechanisms might explain such discordance, but whether it is consistent is uncertain. This study aims to coanalyze paired glycosylated hemoglobin (HbA1c)-fructosamine estimations by using fructosamine to determine a predicted HbA1c, to calculate a glycation gap (G-gap) and to determine whether the G-gap is consistent over time. RESEARCH DESIGN AND METHODS We included 2,263 individuals with diabetes who had at least two paired HbA1c-fructosamine estimations that were separated by 10 ± 8 months. Of these, 1,217 individuals had a third pair. The G-gap was calculated as G-gap = HbA1c minus the standardized fructosamine-derived HbA1c equivalent (FHbA1c). The hypothesis that the G-gap would remain consistent in individuals over time was tested. RESULTS The G-gaps were similar in the first, second, and third paired samples (0.0 ± 1.2, 0.0 ± 1.3, and 0.0 ± 1.3, respectively). Despite significant changes in the HbA1c and fructosamine, the G-gap did not differ in absolute or relative terms and showed no significant within-subject variability. The direction of the G-gap remained consistent. CONCLUSIONS The G-gap appears consistent over time; thus, by inference any key underlying mechanisms are likely to be consistent. G-gap calculation may be a method of exploring and evaluating any such underlying mechanisms.

Association of Glycation Gap With Mortality and Vascular Complications in Diabetes

OBJECTIVE The “glycation gap” (G-gap), an essentially unproven concept, is an empiric measure of disagreement between HbA1c and fructosamine, the two indirect estimates of glycemic control. Its association with demographic features and key clinical outcomes in individuals with diabetes is uncertain. RESEARCH DESIGN AND METHODS The G-gap was calculated as the difference between measured HbA1c and a fructosamine-derived standardized predicted HbA1c in 3,182 individuals with diabetes. The G-gap’s associations with demographics and clinical outcomes (retinopathy, nephropathy, macrovascular disease, and mortality) were determined. RESULTS Demographics varied significantly with G-gap for age, sex, ethnic status, smoking status, type and duration of diabetes, insulin use, and obesity. A positive G-gap was associated with retinopathy (odds ratio 1.24 [95% CI 1.01–1.52], P = 0.039), nephropathy (1.55 [1.23–1.95], P < 0.001), and, in a subset, macrovascular disease (1.91 [1.18–3.09], P = 0.008). In Cox regression analysis, the G-gap had a “U”-shaped quadratic relationship with mortality, with both negative G-gap (1.96 [1.50–2.55], P < 0.001) and positive G-gap (2.02 [1.57–2.60], P < 0.001) being associated with a significantly higher mortality. CONCLUSIONS We confirm published associations of G-gap with retinopathy and nephropathy. We newly demonstrate a relationship with macrovascular and mortality outcomes and potential links to distinct subpopulations of diabetes.

Challenges of emerging adulthood-transition from paediatric to adult diabetes

Diabetes mellitus is a complex condition with far reaching physical, psychological and psychosocial effects. These outcomes can be significant when considering the care of a youth transferring from paediatric through to adult diabetes services. The art of mastering a smooth care transfer is crucial if not pivotal to optimising overall diabetic control. Quite often the nature of consultation varies between the two service providers and the objectives and outcomes will mirror this. The purpose of this review is to analyse the particular challenges and barriers one might expect to encounter when transferring these services over to an adult care provider. Particular emphasis is paid towards the psychological aspects of this delicate period, which needs to be recognised and appreciated appropriately in order to understand the particular plights a young diabetic child will be challenged with. We explore the approaches that can be positively adopted in order to improve the experience for child, parents and also the multi- disciplinary team concerned with the overall delivery of this care. Finally we will close with reflection on the potential areas for future development that will ultimately aim to improve long-term outcomes and experiences of the young adolescent confronted with diabetes as well as the burden of disease and burden of cost of disease.