Browsing by Author "Kollman, Craig"
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Item Assessing the efficacy, safety and utility of 6-month day-and-night automated closed-loop insulin delivery under free-living conditions compared with insulin pump therapy in children and adolescents with type 1 diabetes: an open-label, multicentre, multinational, single-period, randomised, parallel group study protocol(BMJ, 2019-06-03) Musolino, Gianluca; Allen, Janet M.; Hartnell, Sara; Wilinska, Malgorzata E.; Tauschmann, Martin; Boughton, Charlotte; Campbell, Fiona; Denvir, Louise; Trevelyan, Nicola; Wadwa, Paul; DiMeglio, Linda; Buckingham, Bruce A.; Weinzimer, Stuart; Acerini, Carlo L.; Hood, Korey; Fox, Steven; Kollman, Craig; Sibayan, Judy; Borgman, Sarah; Cheng, Peiyao; Hovorka, Roman; Pediatrics, School of MedicineINTRODUCTION: Closed-loop systems titrate insulin based on sensor glucose levels, providing novel means to reduce the risk of hypoglycaemia while improving glycaemic control. We will assess effectiveness of 6-month day-and-night closed-loop insulin delivery compared with usual care (conventional or sensor-augmented pump therapy) in children and adolescents with type 1 diabetes. METHODS AND ANALYSIS: The trial adopts an open-label, multicentre, multinational (UK and USA), randomised, single-period, parallel design. Participants (n=130) are children and adolescents (aged ≥6 and <19 years) with type 1 diabetes for at least 1 year, and insulin pump use for at least 3 months with suboptimal glycaemic control (glycated haemoglobin ≥58 mmol/mol (7.5%) and ≤86 mmol/mol (10%)). After a 2-3 week run-in period, participants will be randomised to 6-month use of hybrid closed-loop insulin delivery, or to usual care. Analyses will be conducted on an intention-to-treat basis. The primary outcome is glycated haemoglobin at 6 months. Other key endpoints include time in the target glucose range (3.9-10 mmol/L, 70-180 mg/dL), mean sensor glucose and time spent above and below target. Secondary outcomes include SD and coefficient of variation of sensor glucose levels, time with sensor glucose levels <3.5 mmol/L (63 mg/dL) and <3.0 mmol/L (54 mg/dL), area under the curve of glucose <3.5 mmol/L (63 mg/dL), time with glucose levels >16.7 mmol/L (300 mg/dL), area under the curve of glucose >10.0 mmol/L (180 mg/dL), total, basal and bolus insulin dose, body mass index z-score and blood pressure. Cognitive, emotional and behavioural characteristics of participants and caregivers and their responses to the closed-loop and clinical trial will be assessed. An incremental cost-effectiveness ratio for closed-loop will be estimated. ETHICS AND DISSEMINATION: Cambridge South Research Ethics Committee and Jaeb Center for Health Research Institutional Review Office approved the study. The findings will be disseminated by peer-review publications and conference presentations.Item Cambridge hybrid closed-loop algorithm in children and adolescents with type 1 diabetes: a multicentre 6-month randomised controlled trial.(Elsevier, 2022-04) Ware, Julia; Boughton, Charlotte K.; Allen, Janet M.; Wilinska, Malgorzata E.; Tauschmann, Martin; Denvir, Louise; Thankamony, Ajay; Campbell, Fiona M.; Wadwa, R. Paul; Buckingham, Bruce A.; Davis, Nikki; DiMeglio, Linda A.; Mauras, Nelly; Besser, Rachel E. J.; Ghatak, Atrayee; Weinzimer, Stuart A.; Hood, Korey K.; Fox, D. Steven; Kanapka, Lauren; Kollman, Craig; Sibayan, Judy; Beck, Roy W.; Hovorka, Roman; Pediatrics, School of MedicineBackground Closed-loop insulin delivery systems have the potential to address suboptimal glucose control in children and adolescents with type 1 diabetes. We compared safety and efficacy of the Cambridge hybrid closed-loop algorithm with usual care over 6 months in this population. Methods In a multicentre, multinational, parallel randomised controlled trial, participants aged 6–18 years using insulin pump therapy were recruited at seven UK and five US paediatric diabetes centres. Key inclusion criteria were diagnosis of type 1 diabetes for at least 12 months, insulin pump therapy for at least 3 months, and screening HbA1c levels between 53 and 86 mmol/mol (7·0–10·0%). Using block randomisation and central randomisation software, we randomly assigned participants to either closed-loop insulin delivery (closed-loop group) or to usual care with insulin pump therapy (control group) for 6 months. Randomisation was stratified at each centre by local baseline HbA1c. The Cambridge closed-loop algorithm running on a smartphone was used with either (1) a modified Medtronic 640G pump, Medtronic Guardian 3 sensor, and Medtronic prototype phone enclosure (FlorenceM configuration), or (2) a Sooil Dana RS pump and Dexcom G6 sensor (CamAPS FX configuration). The primary endpoint was change in HbA1c at 6 months combining data from both configurations. The primary analysis was done in all randomised patients (intention to treat). Trial registration ClinicalTrials.gov, NCT02925299. Findings Of 147 people initially screened, 133 participants (mean age 13·0 years [SD 2·8]; 57% female, 43% male) were randomly assigned to either the closed-loop group (n=65) or the control group (n=68). Mean baseline HbA1c was 8·2% (SD 0·7) in the closed-loop group and 8·3% (0·7) in the control group. At 6 months, HbA1c was lower in the closed-loop group than in the control group (between-group difference −3·5 mmol/mol (95% CI −6·5 to −0·5 [–0·32 percentage points, −0·59 to −0·04]; p=0·023). Closed-loop usage was low with FlorenceM due to failing phone enclosures (median 40% [IQR 26–53]), but consistently high with CamAPS FX (93% [88–96]), impacting efficacy. A total of 155 adverse events occurred after randomisation (67 in the closed-loop group, 88 in the control group), including seven severe hypoglycaemia events (four in the closed-loop group, three in the control group), two diabetic ketoacidosis events (both in the closed-loop group), and two non-treatment-related serious adverse events. There were 23 reportable hyperglycaemia events (11 in the closed-loop group, 12 in the control group), which did not meet criteria for diabetic ketoacidosis. Interpretation The Cambridge hybrid closed-loop algorithm had an acceptable safety profile, and improved glycaemic control in children and adolescents with type 1 diabetes. To ensure optimal efficacy of the closed-loop system, usage needs to be consistently high, as demonstrated with CamAPS FX.Item CGM-measured glucose values have a strong correlation with C-peptide, HbA1c and IDAAC, but do poorly in predicting C-peptide levels in the two years following onset of diabetes(Springer-Verlag, 2015-06) Buckingham, Bruce; Cheng, Peiyao; Beck, Roy W.; Kollman, Craig; Ruedy, Katrina J.; Weinzimer, Stuart A.; Slover, Robert; Bremer, Andrew A.; Fuqua, John; Tamborlane, William; Diabetes Research in Children Network (DirecNet) and Type 1 Diabetes TrialNet Study Groups; Department of Pediatrics, IU School of MedicineAIMS/HYPOTHESIS: The aim of this work was to assess the association between continuous glucose monitoring (CGM) data, HbA1c, insulin-dose-adjusted HbA1c (IDAA1c) and C-peptide responses during the first 2 years following diagnosis of type 1 diabetes. METHODS: A secondary analysis was conducted of data collected from a randomised trial assessing the effect of intensive management initiated within 1 week of diagnosis of type 1 diabetes, in which mixed-meal tolerance tests were performed at baseline and at eight additional time points through 24 months. CGM data were collected at each visit. RESULTS: Among 67 study participants (mean age [± SD] 13.3 ± 5.7 years), HbA1c was inversely correlated with C-peptide at each time point (p < 0.001), as were changes in each measure between time points (p < 0.001). However, C-peptide at one visit did not predict the change in HbA1c at the next visit and vice versa. Higher C-peptide levels correlated with increased proportion of CGM glucose values between 3.9 and 7.8 mmol/l and lower CV (p = 0.001 and p = 0.02, respectively) but not with CGM glucose levels <3.9 mmol/l. Virtually all participants with IDAA1c < 9 retained substantial insulin secretion but when evaluated together with CGM, time in the range of 3.9-7.8 mmol/l and CV did not provide additional value in predicting C-peptide levels. CONCLUSIONS/INTERPRETATION: In the first 2 years after diagnosis of type 1 diabetes, higher C-peptide levels are associated with increased sensor glucose levels in the target range and with lower glucose variability but not hypoglycaemia. CGM metrics do not provide added value over the IDAA1c in predicting C-peptide levels.Item Cost-Effectiveness of Closed-Loop Automated Insulin Delivery Using the Cambridge Hybrid Algorithm in Children and Adolescents with Type 1 Diabetes: Results from a Multicenter 6-Month Randomized Trial(Sage, 2024-03-17) Fox, D. Steven; Ware, Julia; Boughton, Charlotte K.; Allen, Janet M.; Wilinska, Malgorzata E.; Tauschmann, Martin; Denvir, Louise; Thankamony, Ajay; Campbell, Fiona; Wadwa, R. Paul; Buckingham, Bruce A.; Davis, Nikki; DiMeglio, Linda A.; Mauras, Nelly; Besser, Rachel E. J.; Ghatak, Atrayee; Weinzimer, Stuart A.; Kanapka, Lauren; Kollman, Craig; Sibayan, Judy; Beck, Roy W.; Hood, Korey K.; Hovorka, Roman; DAN05 Consortium; Pediatrics, School of MedicineBackground/objective: The main objective of this study is to evaluate the incremental cost-effectiveness (ICER) of the Cambridge hybrid closed-loop automated insulin delivery (AID) algorithm versus usual care for children and adolescents with type 1 diabetes (T1D). Methods: This multicenter, binational, parallel-controlled trial randomized 133 insulin pump using participants aged 6 to 18 years to either AID (n = 65) or usual care (n = 68) for 6 months. Both within-trial and lifetime cost-effectiveness were analyzed. Analysis focused on the treatment subgroup (n = 21) who received the much more reliable CamAPS FX hardware iteration and their contemporaneous control group (n = 24). Lifetime complications and costs were simulated via an updated Sheffield T1D policy model. Results: Within-trial, both groups had indistinguishable and statistically unchanged health-related quality of life, and statistically similar hypoglycemia, severe hypoglycemia, and diabetic ketoacidosis (DKA) event rates. Total health care utilization was higher in the treatment group. Both the overall treatment group and CamAPS FX subgroup exhibited improved HbA1C (-0.32%, 95% CI: -0.59 to -0.04; P = .02, and -1.05%, 95% CI: -1.43 to -0.67; P < .001, respectively). Modeling projected increased expected lifespan of 5.36 years and discounted quality-adjusted life years (QALYs) of 1.16 (U.K. tariffs) and 1.52 (U.S. tariffs) in the CamAPS FX subgroup. Estimated ICERs for the subgroup were £19 324/QALY (United Kingdom) and -$3917/QALY (United States). For subgroup patients already using continuous glucose monitors (CGM), ICERs were £10 096/QALY (United Kingdom) and -$33 616/QALY (United States). Probabilistic sensitivity analysis generated mean ICERs of £19 342/QALY (95% CI: £15 903/QALY to £22 929/QALY) (United Kingdom) and -$28 283/QALY (95% CI: -$59 607/QALY to $1858/QALY) (United States). Conclusions: For children and adolescents with T1D on insulin pump therapy, AID using the Cambridge algorithm appears cost-effective below a £20 000/QALY threshold (United Kingdom) and cost saving (United States).Item Effect of Tight Glycemic Control on Pancreatic Beta Cell Function in Newly Diagnosed Pediatric Type 1 Diabetes: A Randomized Clinical Trial(American Medical Association, 2023) McVean, Jennifer; Forlenza, Gregory P.; Beck, Roy W.; Bauza, Colleen; Bailey, Ryan; Buckingham, Bruce; DiMeglio, Linda A.; Sherr, Jennifer L.; Clements, Mark; Neyman, Anna; Evans-Molina, Carmella; Sims, Emily K.; Messer, Laurel H.; Ekhlaspour, Laya; McDonough, Ryan; Van Name, Michelle; Rojas, Diana; Beasley, Shannon; DuBose, Stephanie; Kollman, Craig; Moran, Antoinette; CLVer Study Group; Pediatrics, School of MedicineImportance: Near normalization of glucose levels instituted immediately after diagnosis of type 1 diabetes has been postulated to preserve pancreatic beta cell function by reducing glucotoxicity. Previous studies have been hampered by an inability to achieve tight glycemic goals. Objective: To determine the effectiveness of intensive diabetes management to achieve near normalization of glucose levels on preservation of pancreatic beta cell function in youth with newly diagnosed type 1 diabetes. Design, setting, and participants: This randomized, double-blind, clinical trial was conducted at 6 centers in the US (randomizations from July 20, 2020, to October 13, 2021; follow-up completed September 15, 2022) and included youths with newly diagnosed type 1 diabetes aged 7 to 17 years. Interventions: Random assignment to intensive diabetes management, which included use of an automated insulin delivery system (n = 61), or standard care, which included use of a continuous glucose monitor (n = 52), as part of a factorial design in which participants weighing 30 kg or more also were assigned to receive either oral verapamil or placebo. Main outcomes and measures: The primary outcome was mixed-meal tolerance test-stimulated C-peptide area under the curve (a measure of pancreatic beta cell function) 52 weeks from diagnosis. Results: Among 113 participants (mean [SD] age, 11.8 [2.8] years; 49 females [43%]; mean [SD] time from diagnosis to randomization, 24 [5] days), 108 (96%) completed the trial. The mean C-peptide area under the curve decreased from 0.57 pmol/mL at baseline to 0.45 pmol/mL at 52 weeks in the intensive management group, and from 0.60 to 0.50 pmol/mL in the standard care group (treatment group difference, -0.01 [95% CI, -0.11 to 0.10]; P = .89). The mean time in the target range of 70 to 180 mg/dL, measured with continuous glucose monitoring, at 52 weeks was 78% in the intensive management group vs 64% in the standard care group (adjusted difference, 16% [95% CI, 10% to 22%]). One severe hypoglycemia event and 1 diabetic ketoacidosis event occurred in each group. Conclusions and relevance: In youths with newly diagnosed type 1 diabetes, intensive diabetes management, which included automated insulin delivery, achieved excellent glucose control but did not affect the decline in pancreatic C-peptide secretion at 52 weeks.Item Effect of Verapamil on Pancreatic Beta Cell Function in Newly Diagnosed Pediatric Type 1 Diabetes: A Randomized Clinical Trial(American Medical Association, 2023) Forlenza, Gregory P.; McVean, Jennifer; Beck, Roy W.; Bauza, Colleen; Bailey, Ryan; Buckingham, Bruce; DiMeglio, Linda A.; Sherr, Jennifer L.; Clements, Mark; Neyman, Anna; Evans-Molina, Carmella; Sims, Emily K.; Messer, Laurel H.; Ekhlaspour, Laya; McDonough, Ryan; Van Name, Michelle; Rojas, Diana; Beasley, Shannon; DuBose, Stephanie; Kollman, Craig; Moran, Antoinette; CLVer Study Group; Pediatrics, School of MedicineImportance: In preclinical studies, thioredoxin-interacting protein overexpression induces pancreatic beta cell apoptosis and is involved in glucotoxicity-induced beta cell death. Calcium channel blockers reduce these effects and may be beneficial to beta cell preservation in type 1 diabetes. Objective: To determine the effect of verapamil on pancreatic beta cell function in children and adolescents with newly diagnosed type 1 diabetes. Design, setting, and participants: This double-blind, randomized clinical trial including children and adolescents aged 7 to 17 years with newly diagnosed type 1 diabetes who weighed 30 kg or greater was conducted at 6 centers in the US (randomized participants between July 20, 2020, and October 13, 2021) and follow-up was completed on September 15, 2022. Interventions: Participants were randomly assigned 1:1 to once-daily oral verapamil (n = 47) or placebo (n = 41) as part of a factorial design in which participants also were assigned to receive either intensive diabetes management or standard diabetes care. Main outcomes and measures: The primary outcome was area under the curve values for C-peptide level (a measure of pancreatic beta cell function) stimulated by a mixed-meal tolerance test at 52 weeks from diagnosis of type 1 diabetes. Results: Among 88 participants (mean age, 12.7 [SD, 2.4] years; 36 were female [41%]; and the mean time from diagnosis to randomization was 24 [SD, 4] days), 83 (94%) completed the trial. In the verapamil group, the mean C-peptide area under the curve was 0.66 pmol/mL at baseline and 0.65 pmol/mL at 52 weeks compared with 0.60 pmol/mL at baseline and 0.44 pmol/mL at 52 weeks in the placebo group (adjusted between-group difference, 0.14 pmol/mL [95% CI, 0.01 to 0.27 pmol/mL]; P = .04). This equates to a 30% higher C-peptide level at 52 weeks with verapamil. The percentage of participants with a 52-week peak C-peptide level of 0.2 pmol/mL or greater was 95% (41 of 43 participants) in the verapamil group vs 71% (27 of 38 participants) in the placebo group. At 52 weeks, hemoglobin A1c was 6.6% in the verapamil group vs 6.9% in the placebo group (adjusted between-group difference, -0.3% [95% CI, -1.0% to 0.4%]). Eight participants (17%) in the verapamil group and 8 participants (20%) in the placebo group had a nonserious adverse event considered to be related to treatment. Conclusions and relevance: In children and adolescents with newly diagnosed type 1 diabetes, verapamil partially preserved stimulated C-peptide secretion at 52 weeks from diagnosis compared with placebo. Further studies are needed to determine the longitudinal durability of C-peptide improvement and the optimal length of therapy.Item Lived experience of CamAPS FX closed loop system in youth with type 1 diabetes and their parents(Wiley, 2022) Hood, Korey K.; Garcia-Willingham, Natasha; Hanes, Sarah; Tanenbaum, Molly L.; Ware, Julia; Boughton, Charlotte K.; Allen, Janet M.; Wilinska, Malgorzata E.; Tauschmann, Martin; Denvir, Louise; Thankamony, Ajay; Campbell, Fiona; Wadwa, R. Paul; Buckingham, Bruce A.; Davis, Nikki; DiMeglio, Linda A.; Mauras, Nelly; Besser, Rachel E. J.; Ghatak, Atrayee; Weinzimer, Stuart A.; Fox, D. Steven; Kanapka, Lauren; Kollman, Craig; Sibayan, Judy; Beck, Roy W.; Hovorka, Roman; DAN05 ConsortiumAim: To examine changes in the lived experience of type 1 diabetes after use of hybrid closed loop (CL), including the CamAPS FX CL system. Materials and methods: The primary study was conducted as an open-label, single-period, randomized, parallel design contrasting CL versus insulin pump (with or without continuous glucose monitoring). Participants were asked to complete patient-reported outcomes before starting CL and 3 and 6 months later. Surveys assessed diabetes distress, hypoglycaemia concerns and quality of life. Qualitative focus group data were collected at the completion of the study. Results: In this sample of 98 youth (age range 6-18, mean age 12.7 ± 2.8 years) and their parents, CL use was not associated with psychosocial benefits overall. However, the subgroup (n = 12) using the CamAPS FX system showed modest improvements in quality of life and parent distress, reinforced by both survey (p < .05) and focus group responses. There were no negative effects of CL use reported by study participants. Conclusions: Closed loop use via the CamAPS FX system was associated with modest improvements in aspects of the lived experience of managing type 1 diabetes in youth and their families. Further refinements of the system may optimize the user experience.Item Predictors of Lost to Follow-Up among Children with Type 2 Diabetes(Karger, 2017-07) Shoemaker, Ashley; Cheng, Peiyao; Gal, Robin L.; Kollman, Craig; Tamborlane, William V.; Klingensmith, Georgeanna J.; Clements, Mark A.; Hannon, Tamara S.; Heptulla, Rubina; Less, Joane; Wood, Jamie; Pediatrics, School of MedicineBackground/Aims: Youth with type 2 diabetes (T2D) have poor compliance with medical care. This study aimed to determine which demographic and clinical factors differ between youth with T2D who receive care in a pediatric diabetes center versus youth lost to follow-up for >18 months. Methods: Data were analyzed from 496 subjects in the Pediatric Diabetes Consortium registry. Enrollment variables were selected a priori and analyzed with univariable and multivariable logistic regression models. Results: After a median of 1.3 years from enrollment, 55% of patients were lost to follow-up. The final model included age, race/ethnicity, parent education, and estimated distance to study site. The odds ratio (99% confidence interval) of loss to follow-up was 2.87 (1.34, 6.16) for those aged 15 to <18 years versus those aged 10 to <13 years and 6.57 (2.67, 16.15) for those aged ≥18 years versus those aged 10 to <13 years. Among patients living more than 50 miles from the clinic, the odds ra tio of loss to follow-up was 3.11 (1.14, 8.49) versus those living within 5 miles of the site. Conclusion: Older adolescents with T2D are more likely to be lost to follow-up, but other socioeconomic factors were not significant predictors of clinic follow-up.Item Safety and prescribing recommendations for verapamil in newly diagnosed pediatric type 1 diabetes (T1D): The CLVer experience(Elsevier, 2024-05-18) Ekhlaspour, Laya; Buckingham, Bruce; Bauza, Colleen; Clements, Mark; Forlenza, Gregory P.; Neyman, Anna; Norlander, Lisa; Schamberger, Marcus; Sherr, Jennifer L.; Bailey, Ryan; Beck, Roy W.; Kollman, Craig; Beasley, Shannon; Cobry, Erin; DiMeglio, Linda A.; Paprocki, Emily; Van Name, Michelle; Moran, Antoinette; CLVer Study Group; Pediatrics, School of MedicineObjectives: To report the safety and side effects associated with taking verapamil for beta-cell preservation in children with newly-diagnosed T1D. Research design and methods: Eighty-eight participants aged 8.5 to 17.9 years weighing ≥ 30 kg were randomly assigned to verapamil (N = 47) or placebo (N = 41) within 31 days of T1D diagnosis and followed for 12 months from diagnosis, main CLVer study. Drug dosing was weight-based with incremental increases to full dosage. Side effect monitoring included serial measurements of pulse, blood pressure, liver enzymes, and electrocardiograms (ECGs). At study end, participants were enrolled in an observational extension study (CLVerEx), which is ongoing. No study drug is provided during the extension, but participants may use verapamil if prescribed by their diabetes care team. Results: Overall rates of adverse events were low and comparable between verapamil and placebo groups. There was no difference in the frequency of liver function abnormalities. Three CLVer participants reduced or discontinued medication due to asymptomatic ECG changes. One CLVerEx participant (18 years old), treated with placebo during CLVer, who had not had a monitoring ECG, experienced complete AV block with a severe hypotensive episode 6 weeks after reaching his maximum verapamil dose following an inadvertent double dose on the day of the event. Conclusions: The use of verapamil in youth newly-diagnosed with T1D appears generally safe and well tolerated with appropriate monitoring. We strongly recommend monitoring for potential side effects including an ECG at screening and an additional ECG once full dosage is reached.Item The Association of High and Low Glycation With Incident Diabetic Retinopathy in Adults With Type 1 Diabetes(Sage, 2024-05-28) Shah, Viral N.; Kanapka, Lauren G.; Karakus, Kagan Ege; Kollman, Craig; Beck, Roy W.; Medicine, School of MedicineBackground: We investigated the risk of incident diabetic retinopathy (DR) among high glycator compared to low glycator patients based on the hemoglobin glycation index (HGI). Visit-to-visit variations in HGI also were assessed. Methods: Glycated hemoglobin (HbA1c) and continuous glucose monitoring data were collected up to 7 years prior to the date of eye examination defining incident DR or no retinopathy (control). Hemoglobin glycation index was calculated as difference in measured HbA1c and an estimated A1c from sensor glucose (eA1c) to define high (HbA1c - eA1c >0%) or low (HbA1c - eA1c <0%) glycator. Stable glycators were defined as ≥75% of visits with same HGI category. Logistic regression was used to assess the association between glycation category and incident DR. Results: Of 119 adults with type 1 diabetes (T1D), 49 (41%) were stable low glycator (HbA1c - eA1c <0%), 36 (30%) were stable high glycator (HbA1c - eA1c >0%), and 34 (29%) were unstable glycator. Using alternate criteria to define high vs low glycator (consistent difference in HbA1c - eA1c of > 0.4% or <0.4%, respectively), 53% of the adults were characterized as unstable glycator. Compared to low glycators, high glycators did not have a significantly higher risk for incident DR over time when adjusted for age, T1D duration and continuous glucose monitoring (CGM) sensor type (odds ratio [OR] = 1.31, 95% confidence interval [CI] = 0.48-3.62, P = .15). Conclusions: The risk of diabetic retinopathy was not found to differ significantly comparing high glycators to low glycators in adults with T1D. Moreover, HbA1c - eA1c relationship was not stable in nearly 30% to 50% adults with T1D, suggesting that discordance in HbA1c and eA1c are mostly related either HbA1c measurements or estimation of A1c from sensor glucose rather than physiological reasons.