The Fallacy of Average: How Using HbA1c Alone to Assess Glycemic Control Can Be Misleading

Continuous Glucose Monitoring Profiles in Healthy, Nondiabetic Young Children

Context

Continuous glucose monitoring (CGM) is increasingly being used for both day-to-day management in patients with diabetes and in clinical research. While data on glycemic profiles of healthy, non-diabetic individuals exists, data on non-diabetic very young children are lacking.

Objective

To establish reference sensor glucose ranges in healthy, non-diabetic young children, using a current generation CGM sensor.

Design

Prospective observational study

Setting

Institutional practice

Participants

Healthy, non-diabetic children 1-6 years old; with normal body mass index

Intervention

A blinded Dexcom G6 Pro CGM was worn for approximately 10 days by each participant.

Main Outcome Measure

CGM metrics of mean glucose, hyperglycemia, hypoglycemia, and glycemic variability

Results

39 participants were included in the analyses. Mean average glucose was 103 mg/dL (5.7 mmol/L). Median % time between 70-140 mg/dL (3.9-7.8 mmol/L) was 96% (IQR 92%-97%), mean within-individual coefficient of variation was 17±3%, median time spent with glucose levels >140mg/dL was 3.4% (49 min/day), and median time <70 mg/dL (3.9 mmol/L) was 0.4% (6 min/day).

Conclusions

Collecting normative sensor glucose data and describing glycemic measures for young children fills an important informational gap and will be useful as a benchmark for future clinical studies.

Understanding the clinical implications of differences between glucose management indicator and glycated haemoglobin

Laboratory measured glycated haemoglobin (HbA1c) is the gold standard for assessing glycaemic control in people with diabetes and correlates with their risk of long-term complications. The emergence of continuous glucose monitoring (CGM) has highlighted limitations of HbA1c testing. HbA1c can only be reviewed infrequently and can mask the risk of hypoglycaemia or extreme glucose fluctuations. While CGM provides insights in to the risk of hypoglycaemia as well as daily fluctuations of glucose, it can also be used to calculate an estimated HbA1c that has been used as a substitute for laboratory HbA1c. However, it is evident that estimated HbA1c and HbA1c values can differ widely. The glucose management indicator (GMI), calculated exclusively from CGM data, has been proposed. It uses the same scale (% or mmol/mol) as HbA1c, but is based on short-term average glucose values, rather than long-term glucose exposure. HbA1c and GMI values differ in up to 81% of individuals by more than ±0.1% and by more than ±0.3% in 51% of cases. Here, we review the factors that define these differences, such as the time period being assessed, the variation in glycation rates and factors such as anaemia and haemoglobinopathies. Recognizing and understanding the factors that cause differences between HbA1c and GMI is an important clinical skill. In circumstances when HbA1c is elevated above GMI, further attempts at intensification of therapy based solely on the HbA1c value may increase the risk of hypoglycaemia. The observed difference between GMI and HbA1c also informs the important question about the predictive ability of GMI regarding long-term complications.

Hemoglobin within normal range is negatively related to hemoglobin A1c in a nondiabetic American population aged 16 years and older

BACKGROUND

Protein glycosylated hemoglobin, hemoglobin A1c (HbA1c) binds hemoglobin (Hb) in red blood cells to blood glucose. However, the relationship between Hb and HbA1c remains unclear.

AIM

To elucidate their relationship in a nondiabetic population aged ≥ 16 years in the United States, using data from the 1999-2018 National Health and Nutrition Examination Survey.

METHODS

This study was based on data from 44560 adults aged ≥ 16 years, excluding those with diabetes. The relationship was estimated using a multivariate regression. We also used piecewise linear regression for subgroup analysis based on age and sex stratification and analysis of the threshold effects of Hb on HbA1c.

RESULTS

Hb and HbA1c levels were negatively correlated in the unadjusted model (β = -0.01; 95%CI: -0.01, -0.01). The correlation was significantly negative when the regression model was minimally regulated and stratified by age and sex, and remained negative when the model was further regulated (more than 10%) to identify covariates with the HbA1c level influence estimates. In subgroup analyses based on age and sex stratification, the association remained negative when the covariates were controlled. A nonlinear relationship was observed between them when the Hb levels reached the tipping point (13.2 g/dL) (adjusted odds ratio, -0.04; 95%CI: -0.05, -0.03) and when the Hb levels exceeded 13.2 g/dL (adjusted odds ratio, -0.10; 95%CI: -0.10, -0.09).

CONCLUSION

Our study shows that normal Hb levels are negatively correlated with HbA1c in nondiabetic Americans aged ≥ 16 years.

HbA1c Is Disproportionately Higher in Women and Older People With Type 1 Diabetes Compared With Flash Glucose Monitoring Metrics of Glycemic Control

AIMS

Discrepancy between HbA1c and glucose exposure may have significant clinical implications. We sought to assess predictors of disparity between HbA1c and flash monitoring metrics and how these relate to microvascular complications.

METHODS

We conducted a cross-sectional study of adults with type 1 diabetes (n = 518). We assessed the relationship between clinic HbA1c and flash monitoring metrics, predictors of discrepancy between these measurements, and whether discrepancy was associated with microvascular complications.

RESULTS

Actual HbA1c and estimated HbA1c were strongly correlated (r = .779, P < .001). The likelihood of having a higher actual HbA1c than estimated HbA1c was greater with increasing age (OR = 1.055 per year, P < .001) and lower in men (OR = .208, P < .001). HbA1c was significantly lower in men (58 mmol/mol [51-67]) (7.5% [6.8-8.3]) compared to women (61 mmol/mol [54-70], P = .021) (7.7% [7.1-8.6]), despite no significant differences in any flash monitoring metrics. Whereas HbA1c was not different between younger (≤39 years) and older individuals (>39 years) despite significantly higher glucose exposure, in younger people, based on multiple flash monitoring metrics. Having a lower estimated than actual HbA1c was independently associated with a lower prevalence of retinopathy (OR = .55, P = .004).

CONCLUSIONS

HbA1c appears to overestimate glucose exposure in women and older people with type 1 diabetes. This has potentially important clinical implications, as is hinted at by the independent relationship with retinopathy prevalence. It may also be of relevance when considering the use of HbA1c for the diagnosis of diabetes.

Randomized comparison of self-monitored blood glucose (BGM) versus continuous glucose monitoring (CGM) data to optimize glucose control in type 2 diabetes

AIMS

Evaluate whether structured BGM testing (BGM) or real-time CGM (CGM) lead to improved glucose control (A1c). Determine which approach optimized glucose control more effectively. METHODS-MULTI-ARM PARALLEL: trial of three type 2 diabetes (T2D) therapies ± metformin: (1) sulfonylurea (SU), (2) incretin (DPP4 inhibitor or GLP-1 agonist), or (3) insulin. After a baseline CGM, 114 adult subjects were randomized to either BGM (4 times daily) or CGM (24/7) for 16 weeks with therapies adjusted every 4 weeks.

RESULTS

A1c means decreased from 8.19 to 7.07 (1.12% difference) with CGM (n = 59) and 7.85 to 7.03 (0.82% difference) with BGM (n = 55) (p < 0.001). BGM and CGM groups showed significant improvements in time in range and glucose variability-with no significant difference between the two groups. Clinically important hypoglycemia (<50 mg/dL) was significantly reduced for the CGM group compared with BGM (p < 0.01), particularly in subjects taking insulin or therapies with higher hypoglycemic risk (SU).

CONCLUSION

In T2D, structured, consistent use of glucose data regardless of device (structured BGM or CGM) leads to improvements in A1c control. CGM is more effective than BGM in minimizing hypoglycemia particularly for those using higher hypoglycemic risk therapies.

Consensus report: Definition and interpretation of remission in type 2 diabetes

Improvement of glucose levels into the normal range can occur in some people living with diabetes, either spontaneously or after medical interventions, and in some cases can persist after withdrawal of glucose-lowering pharmacotherapy. Such sustained improvement may now be occurring more often due to newer forms of treatment. However, terminology for describing this process and objective measures for defining it are not well established, and the long-term risks versus benefits of its attainment are not well understood. To update prior discussions of this issue, an international expert group was convened by the American Diabetes Association to propose nomenclature and principles for data collection and analysis, with the goal of establishing a base of information to support future clinical guidance. This group proposed "remission" as the most appropriate descriptive term, and HbA1c <6.5% (48 mmol/mol) measured at least 3 months after cessation of glucose-lowering pharmacotherapy as the usual diagnostic criterion. The group also made suggestions for active observation of individuals experiencing a remission and discussed further questions and unmet needs regarding predictors and outcomes of remission.

Impact of flash glucose monitoring on glycemic control varies with the age and residual β-cell function of patients with type 1 diabetes mellitus

AIMS/INTRODUCTION

We aimed to explore the clinical factors associated with glycemic variability (GV) assessed with flash glucose monitoring (FGM), and investigate the impact of FGM on glycemic control among Chinese type 1 diabetes mellitus patients in a real-life clinical setting.

MATERIALS AND METHODS

A total of 171 patients were included. GV was assessed from FGM data. A total of 110 patients wore FGM continuously for 6 months (longitudinal cohort). Hemoglobin A1c (HbA1c), fasting and 2-h postprandial C-peptide, and glucose profiles were collected. Changes in HbA1c and glycemic parameters were assessed during a 6-month FGM period.

RESULTS

Individuals with high residual C-peptide (HRCP; 2-h postprandial C-peptide >200 pmol/L) had less GV than patients with low residual C-peptide ( 2-h postprandial C-peptide ≤200 pmol/L; P < 0.001). In the longitudinal cohort (n = 110), HbA1c and mean glucose decreased, time in range (TIR) increased during the follow-up period (P < 0.05). The 110 patients were further divided into age and residual C-peptide subgroups: (i) HbA1c and mean glucose were reduced significantly only in the subgroup aged ≤14 years during the follow-up period, whereas time below range also increased in this subgroup at 3 months (P = 0.047); and (ii) HbA1c improved in the HRCP subgroup at 3 and 6 months (P < 0.05). The mean glucose decreased and TIR improved significantly in the low residual C-peptide subgroup; however, TIR was still lower and time below range was higher than those of the HRCP subgroup at all time points (P < 0.05).

CONCLUSIONS

HRCP was associated with less GV. FGM wearing significantly reduced HbA1c, especially in pediatric patients and those with HRCP. Additionally, the mean glucose and TIR were also found to improve.

Effects of personalized diets by prediction of glycemic responses on glycemic control and metabolic health in newly diagnosed T2DM: a randomized dietary intervention pilot trial

BACKGROUND

Dietary modifications are crucial for managing newly diagnosed type 2 diabetes mellitus (T2DM) and preventing its health complications, but many patients fail to achieve clinical goals with diet alone. We sought to evaluate the clinical effects of a personalized postprandial-targeting (PPT) diet on glycemic control and metabolic health in individuals with newly diagnosed T2DM as compared to the commonly recommended Mediterranean-style (MED) diet.

METHODS

We enrolled 23 adults with newly diagnosed T2DM (aged 53.5 ± 8.9 years, 48% males) for a randomized crossover trial of two 2-week-long dietary interventions. Participants were blinded to their assignment to one of the two sequence groups: either PPT-MED or MED-PPT diets. The PPT diet relies on a machine learning algorithm that integrates clinical and microbiome features to predict personal postprandial glucose responses (PPGR). We further evaluated the long-term effects of PPT diet on glycemic control and metabolic health by an additional 6-month PPT intervention (n = 16). Participants were connected to continuous glucose monitoring (CGM) throughout the study and self-recorded dietary intake using a smartphone application.

RESULTS

In the crossover intervention, the PPT diet lead to significant lower levels of CGM-based measures as compared to the MED diet, including average PPGR (mean difference between diets, - 19.8 ± 16.3 mg/dl × h, p < 0.001), mean glucose (mean difference between diets, - 7.8 ± 5.5 mg/dl, p < 0.001), and daily time of glucose levels > 140 mg/dl (mean difference between diets, - 2.42 ± 1.7 h/day, p < 0.001). Blood fructosamine also decreased significantly more during PPT compared to MED intervention (mean change difference between diets, - 16.4 ± 37 μmol/dl, p < 0.0001). At the end of 6 months, the PPT intervention leads to significant improvements in multiple metabolic health parameters, among them HbA1c (mean ± SD, - 0.39 ± 0.48%, p < 0.001), fasting glucose (- 16.4 ± 24.2 mg/dl, p = 0.02) and triglycerides (- 49 ± 46 mg/dl, p < 0.001). Importantly, 61% of the participants exhibited diabetes remission, as measured by HbA1c < 6.5%. Finally, some clinical improvements were significantly associated with gut microbiome changes per person.

CONCLUSION

In this crossover trial in subjects with newly diagnosed T2DM, a PPT diet improved CGM-based glycemic measures significantly more than a Mediterranean-style MED diet. Additional 6-month PPT intervention further improved glycemic control and metabolic health parameters, supporting the clinical efficacy of this approach.

TRIAL REGISTRATION

ClinicalTrials.gov number, NCT01892956.

Closed-Loop Insulin Delivery Versus Sensor-Augmented Pump Therapy in Older Adults With Type 1 Diabetes (ORACL): A Randomized, Crossover Trial

OBJECTIVE

To assess the efficacy and safety of closed-loop insulin delivery compared with sensor-augmented pump therapy among older adults with type 1 diabetes.

RESEARCH DESIGN AND METHODS

This open-label, randomized (1:1), crossover trial compared 4 months of closed-loop versus sensor-augmented pump therapy. Eligible adults were aged ≥60 years, with type 1 diabetes (duration ≥10 years), using an insulin pump. The primary outcome was continuous glucose monitoring (CGM) time in range (TIR; 3.9-10.0 mmol/L).

RESULTS

There were 30 participants (mean age 67 [SD 5] years), with median type 1 diabetes duration of 38 years (interquartile range [IQR] 20-47), randomized (n = 15 to each sequence); all completed the trial. The mean TIR was 75.2% (SD 6.3) during the closed-loop stage and 69.0% (9.1) during the sensor-augmented pump stage (difference of 6.2 percentage points [95% CI 4.4 to 8.0]; P < 0.0001). All prespecified CGM metrics favored closed loop over the sensor-augmented pump; benefits were greatest overnight. Closed loop reduced CGM time <3.9 mmol/L during 24 h/day by 0.5 percentage points (95% CI 0.3 to 1.1; P = 0.0005) and overnight by 0.8 percentage points (0.4 to 1.1; P < 0.0001) compared with sensor-augmented pump. There was no significant difference in HbA1c between closed-loop versus sensor-augmented pump stages (7.3% [IQR, 7.1-7.5] (56 mmol/mol [54-59]) vs. 7.5% [7.1-7.9] (59 mmol/mol [54-62]), respectively; P = 0.13). Three severe hypoglycemia events occurred during the closed-loop stage and two occurred during the sensor-augmented pump stage; no hypoglycemic events required hospitalization. One episode of diabetic ketoacidosis occurred during the sensor-augmented pump stage; no serious adverse events occurred during the closed-loop stage.

CONCLUSIONS

Closed-loop therapy is an effective treatment option for older adults with long-duration type 1 diabetes, and no safety issues were identified. These older adults had higher TIR accompanied by less time below range during closed loop than during sensor-augmented pump therapy. Of particular clinical importance, closed loop reduced the time spent in hypoglycemic range overnight.

Recent Updates to Clinical Practice Guidelines for Diabetes Mellitus

Guidelines for the management of patients with diabetes have become an important part of clinical practice that improve the quality of care and help establish evidence-based medicine in this field. With rapidly accumulating evidence on various aspects of diabetes care, including landmark clinical trials of treatment agents and newer technologies, timely updates of the guidelines capture the most current state of the field and present a consensus. As a leading academic society, the Korean Diabetes Association publishes practice guidelines biennially and the American Diabetes Association does so annually. In this review, we summarize the key changes suggested in the most recent guidelines. Some of the important updates include treatment algorithms emphasizing comorbid conditions such as atherosclerotic cardiovascular disease, heart failure, and chronic kidney disease in the selection of anti-diabetic agents; wider application of continuous glucose monitoring (CGM), insulin pump technologies and indices derived from CGM such as time in range; more active screening of subjects at high-risk of diabetes; and more detailed individualization in diabetes care. Although there are both similarities and differences among guidelines and some uncertainty remains, these updates provide a good approach for many clinical practitioners who are battling with diabetes.

A prospective multicentre open label study to assess effect of Teneligliptin on glycemic control through parameters of time in range (TIR) Metric using continuous glucose monitoring (TOP-TIR study)

BACKGROUND AND AIMS

Continuous glucose monitoring (CGM) has been effective in assessing glycemic variability in diabetic patients. This study aims at assessing the effect of Teneligliptin using ambulatory glucose profile (AGP) indicators.

METHODS

A prospective, multicentre, open label study enrolling 59 type 2 diabetes patients between 18 and 65 years age was done between November 2020-May 2021. Patients were administered Teneligliptin 20 mg once daily, in addition to Metformin. The study included pre-treatment and two post-treatment phases. The data on time in range (TIR) and other AGP indicators of glycemic variability were obtained on each patient in all the three study phases and analysed to understand the effect of Teneligliptin on glycemic variability. Safety evaluation was done based on vital and biochemical parameters.

RESULTS

The percent TIR in post-treatment phase I was significantly higher than the pre-treatment phase (p < 0.0001), and was maintained till the end of phase II (p = 0.037). There was significant lowering of time above range (≥180 mg/dL) in the phase I (p = 0.003), which was maintained in phase II (p = 0.043), suggesting better control over hyperglycemic state. The reduction in mean glucose level in phase I and II was also significant compared to baseline (p = 0.003 and p = 0.023 respectively). The glucose variability percent and glucose management indicator also showed significant lowering in both the phases.

CONCLUSIONS

Teneligliptin addition to patients uncontrolled on Metformin monotherapy significantly reduced glycemic variability, as well showed significant glycemic improvement. Since this study was a single arm study, a comparative study with other DPP-4 inhibitors is needed.

Negative association of time in range and urinary albumin excretion rate in patients with type 2 diabetes mellitus: a retrospective study of inpatients

Background:

Time in range (TIR) refers to the time an individual spends within their target glucose range, which now has been popularized as an important metric to classify glycemic management and also recognized as an important outcome of current diabetes therapies. This study aimed to investigate the association between TIR and the severity of the urinary albumin excretion rate (UAER) in patients with type 2 diabetes mellitus (T2DM).

Methods:

We retrospectively analyzed the data of 1014 inpatients with T2DM at the Department of Endocrinology and Metabolism of Peking University International Hospital, China. TIR was defined as the percentage of blood glucose within the target range of 3.90–10.00 mmol/L. Urine samples for assessment of UAER were collected for 3 consecutive days from the start of hospitalization.

Results:

The TIR values for patients with normal urine levels of albumin, microalbuminuria, and macroalbuminuria were 70% ± 20%, 50% ± 20%, and 30% ± 20%, respectively (all P < 0.001). The patients were stratified according to quartiles of TIR as follows: quartile (Q) 1, <55%; Q2, 55%–72%; Q3, 73%–83%; and Q4, >83%. The incidences of microalbuminuria in Q1, Q2, Q3, and Q4 were 41.1%, 21.6%, 7.1%, and 5.5% (all P < 0.001), respectively. The respective incidences of macroalbuminuria were 24.2%, 1.1%, 1.4%, and 0% (all P < 0.001). In multinomial logistic regression analyses, TIR was significantly correlated with microalbuminuria (odds ratio [OR] 0.58, 95% confidence interval [CI]: 0.52–0.65, P < 0.001) and macroalbuminuria (OR 0.26, 95% CI: 0.18–0.38, P < 0.001) after adjusting for age, sex, body mass index, diabetes duration, systolic blood pressure, and levels of triglycerides, glycosylated hemoglobin A1c, and creatinine.

Conclusion:

The proportion of blood glucose in TIR is closely related to the severity of UAER in patients with T2DM.

Relationship Between Time in Range, Glycemic Variability, HbA1c, and Complications in Adults With Type 1 Diabetes Mellitus

PURPOSE

Real-time continuous glucose monitoring (RT-CGM) provides information on glycemic variability (GV), time in range (TIR), and guidance to avoid hypoglycemia, thereby complimenting HbA1c for diabetes management. We investigated whether GV and TIR were independently associated with chronic and acute diabetes complications.

METHODS

Between September 2014 and January 2017, 515 subjects with type 1 diabetes using sensor-augmented pump therapy were followed for 24 months. The link between baseline HbA1c and CGM-derived glucometrics (TIR [70-180 mg/dL], coefficient of variation [CV], and SD) obtained from the first 2 weeks of RT-CGM use and the presence of complications was investigated. Complications were defined as: composite microvascular complications (presence of neuropathy, retinopathy, or nephropathy), macrovascular complications, and hospitalization for hypoglycemia and/or ketoacidosis.

RESULTS

Individuals with microvascular complications were older (P < 0.001), had a longer diabetes duration (P < 0.001), a higher HbA1c (7.8 ± 0.9 vs 7.5 ± 0.9%, P < 0.001), and spent less time in range (60.4 ± 12.2 vs 63.9 ± 13.8%, P = 0.022) compared with those without microvascular complication. Diabetes duration (odds ratio [OR] = 1.12 [1.09-1.15], P < 0.001) and TIR (OR = 0.97 [0.95-0.99], P = 0.005) were independent risk factors for composite microvascular complications, whereas SD and CV were not. Age (OR = 1.08 [1.03-1.14], P = 0.003) and HbA1c (OR = 1.80 [1.02-3.14], P = 0.044) were risk factors for macrovascular complications. TIR (OR = 0.97 [0.95-0.99], P = 0.021) was the only independent risk factor for hospitalizations for hypoglycemia or ketoacidosis.

CONCLUSIONS

Lower TIR was associated with the presence of composite microvascular complications and with hospitalization for hypoglycemia or ketoacidosis. TIR, SD, and CV were not associated with macrovascular complications.

Glycemic Metrics Derived From Intermittently Scanned Continuous Glucose Monitoring

BACKGROUND

Glucose data from intermittently scanned continuous glucose monitoring (isCGM) is a combination of scanned and imported glucose values. The present knowledge of glycemic metrics originate mostly from glucose data from real-time CGM sampled every five minutes with a lack of information derived from isCGM.

METHODS

Glucose data obtained with isCGM and hemoglobin A1c (HbA1c) were obtained from 169 patients with type 1 diabetes. Sixty-one patients had two observations with an interval of more than three months.

RESULTS

The best regression line of HbA1c against mean glucose was observed from 60 days prior to HbA_1c measurement as compared to 14, 30, and 90 days. The difference between HbA1c and estimated HbA1c (=glucose management indicator [GMI]) first observed correlated with the second observation (R2 0.61, P < .001). Time in range (TIR, glucose between 3.9 and 10 mmol/L) was significantly related to GMI (R2 0.87, P < .001). A TIR of 70% corresponded to a GMI of 6.8% (95% confidence interval, 6.3-7.4). The fraction of patients with the optimal combination of TIR >70% and time below range (TBR) <4% was 3.6%. The fraction of patients with TBR>4% was four times higher for those with high glycemic variability (coefficient of variation [CV] >36%) than for those with lower CV.

CONCLUSION

The individual difference between HbA1c and GMI was reproducible. High glycemic variability was related to increased TBR. A combination of TIR and TBR is suggested as a new composite quality indicator.

American Diabetes Association Professional Practice Committee. 6. Glycemic Targets: Standards of Medical Care in Diabetes-2022

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc22-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc22-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Association of continuous glucose monitoring-derived time in range with major amputation risk in diabetic foot osteomyelitis patients undergoing amputation

OBJECTIVE

The metrics generated from continuous glucose monitoring (CGM), such as time in range (TIR), are strongly correlated with diabetes complications. This study explored the association of perioperative CGM-derived metrics with major amputation risk in patients with diabetic foot osteomyelitis (DFO).

METHODS

This study recruited 55 DFO patients with grade 3-4 wounds according to the Wagner Diabetic Foot Ulcer Classification System, all of whom underwent CGM for 5 days during the perioperative period. The CGM-derived metrics were defined in accordance with the most recent international consensus recommendations.

RESULTS

Patients with major amputation had significantly less TIR and higher time below range (TBR) (all p < 0.05). In binary logistic regression analyses, a lower TIR was associated with the risk of major amputation (odds ratio: 0.83 (95% confidence interval: 0.71-0.99), p = 0.039). This association remained statistically significant after adjustments for age, sex, body mass index, type of diabetes, smoking, drinking, durations of diabetes and DFU, ankle-brachial index, albumin, estimated-glomerular filtration rate, Society for Vascular Surgery wound, ischemia, and foot infection (WIfi) stage, multidrug-resistant organisms, and hemoglobin A1c. Further adjustment for the mean amplitude of glycemic excursion (MAGE) reduced this association. TBR was also independently associated with the risk of major amputation (odds ratio: 1.60 (95% confidence interval: 1.17-2.18), p = 0.003); this association persisted after adjustment for MAGE.

CONCLUSION

Perioperative TIR (3.9-10.0 mmol/L) and TBR (<3.9 mmol/L) were significantly associated with major amputation in hospitalized patients with DFO.

Type 1 Diabetes in Pregnancy: A Review of Complications and Management

BACKGROUND

Pre-gestational diabetes can pose significant risk to the mother and infant, thus requiring careful counselling and management. Since Saint Vincent's declaration in 1989, adverse maternal and fetal outcomes, such as preeclampsia, perinatal mortality, congenital anomalies, and macrosomia, continue to be associated with type 1 diabetes. Although pregnancy is not considered an independent risk factor for the development of new onset microvascular complications, it is known to exacerbate pre-existing microvascular disease. Strict glycaemic control is the optimal management for pre-existing type 1 diabetes in pregnancy, as raised HbA1C is associated with increased risk of maternal and fetal complications. More recently, time in range on Continuous Glucose Monitoring glucose profiles has emerged as another useful evidence-based marker of fetal outcomes.

OBJECTIVES

This review summarises the complications associated with pre-gestational type 1 diabetes, appropriate evidence-based management, including preparing for pregnancy, intrapartum and postpartum care.

METHODS

A structured search of the PubMed and Cochrane databases was conducted. Peer-reviewed articles about complications and management guidelines on pre-gestational type 1 diabetes were selected and critically appraised.

RESULTS

One hundred and twenty-three manuscripts were referenced and appraised in this review, and international guidelines were summarised.

CONCLUSION

This review provides a comprehensive overview of the recurring themes in the literature pertaining to type 1 diabetes in pregnancy: maternal and fetal complications, microvascular disease progression, and an overview of current guideline-specific management.

Consensus Report: Definition and Interpretation of Remission in Type 2 Diabetes

Improvement of glucose levels into the normal range can occur in some people living with diabetes, either spontaneously or after medical interventions, and in some cases can persist after withdrawal of glucose-lowering pharmacotherapy. Such sustained improvement may now be occurring more often due to newer forms of treatment. However, terminology for describing this process and objective measures for defining it are not well established, and the long-term risks versus benefits of its attainment are not well understood. To update prior discussions of this issue, an international expert group was convened by the American Diabetes Association to propose nomenclature and principles for data collection and analysis, with the goal of establishing a base of information to support future clinical guidance. This group proposed "remission" as the most appropriate descriptive term, and HbA1c < 6.5% (48 mmol/mol) measured at least 3 months after cessation of glucose-lowering pharmacotherapy as the usual diagnostic criterion. The group also made suggestions for active observation of individuals experiencing a remission and discussed further questions and unmet needs regarding predictors and outcomes of remission.

The automated pancreas: A review of technologies and clinical practice

Insulin pumps and glucose sensors are effective in improving diabetes therapy and reducing acute complications. The combination of both devices using an algorithm-driven interoperable controller makes automated insulin delivery (AID) systems possible. Many AID systems have been tested in clinical trials and have proven safety and effectiveness. However, currently, none of these systems are available for routine use in children younger than 6 years in Europe. For continued use, both users and prescribers must have sound knowledge of the features of the individual AID systems. Presently, all systems require various user interactions (e.g. meal announcements) because fully automated systems are not yet developed. Open-source systems are non-regulated variants to circumvent existing regulatory conditions. There are risks here for both users and prescribers. To evaluate AID therapy, the metric data of the glucose sensors, 'time in target range' and 'glucose management index', are novel recognized and suitable parameters allowing a consultation based on real glucose and insulin pump download data from the daily life of people with diabetes. Read out via cloud-based software or automatic download of such individual treatment data provides the ideal technical basis for shared decision-making through telemedicine, which must be further evaluated for general use.

Time in range, as measured by continuous glucose monitor, as a predictor of microvascular complications in type 2 diabetes: a systematic review

Continuous glucose monitoring (CGM)-derived time in range (TIR) correlates with hemoglobin A1c (A1c) among patients with type 2 diabetes mellitus (T2DM); however, there is a paucity of data evaluating its association with microvascular complications. We conducted this systematic review to examine the association between TIR and microvascular complications of diabetic retinopathy (DR), diabetic nephropathy (DN), and diabetic peripheral neuropathy (DPN). We conducted a comprehensive literature search on PubMed, Scopus, and Web of Science online databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Full-text original articles that evaluated the association between CGM-derived TIR and risk of microvascular complications and were published between 2010 and June 2021 were included in our systematic review. The quality of the included studies was evaluated using the National Heart, Lung, and Blood Institute Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Data were analyzed using qualitative synthesis. Eleven studies on a total of 13 987 patients were included in the systematic review. The median sample size, baseline A1c, and diabetes duration were 466 patients (range: 105-5901), 8.2% (SD 0.5%), and 11.3 years (1.0), respectively. Majority of the studies were conducted in Asia (10 out of 11). Four studies evaluated the relationship between CGM-derived TIR and DR and CGM-derived TIR and DN, while seven studies evaluated the relationship between CGM-derived TIR and DPN. A 10% increase in TIR was associated with a reduction in albuminuria, severity of DR, and prevalence of DPN and cardiac autonomic neuropathy. In addition, an association was observed between urinary albumin to creatinine ratio but not with estimated glomerular filtration rate. This review summarizes recent evidence supporting an association between CGM-derived TIR and microvascular complications among patients with T2DM. A larger-scale multicenter investigation that includes more diverse participants is warranted to further validate the utility of TIR as a predictor of diabetic microvascular complications.

Time in range: new parameter to evaluate blood glucose control

Continuous glucose monitoring became more common in everyday clinical practice. New parameters have been created as a standard for assessing the degree of control for people with diabetes and can be used more clearly than glycated haemoglobin. The new parameter time in range represents a significant benefit not only for diabetologists, but also an important tool to help the patients in their daily lives with diabetes.

Should the Quality of Glycemic Control Guide Dental Implant Therapy in Patients with Diabetes? Focus on Implant Survival

INTRODUCTION

Optimal glycemic control is crucial to dental implant long-term functional and esthetic success. Despite HbA1c levels of 7% or lower used is as an indicator for good glycemic control, however, this level may not be attainable for all diabetic patients. Most dentists do not consider patients with poor glycemic control candidates for implant therapy due to higher implant failure, infection or other complications.

AIM

This review challenges the concept of one size fits all and aims to critically appraise the evidence for the success or failure rate of dental implants and peri-implant health outcomes in patients with less than optimal glycemic control.

DISCUSSION

Evidence suggests that estimating glycemic control from HbA1c measurement alone is misleading. Moreover, elevated preoperative HbA1c was not associated with increased mortality and morbidity after major surgical procedures. Literature for the survival or success of implants in diabetic patients is inconsistent due to a lack of standardized reporting of clinical data collection and outcomes. While a number of studies report that implant treatment in patients with well controlled diabetes has a similar success rate to healthy individuals, other studies suggest that the quality of glycemic control in diabetic patients does not make a difference in the implant failure rate or marginal bone loss. This discrepancy could indicate that risk factors other than hyperglycemia may contribute to the survival of implants in diabetic patients.

CONCLUSION

In the era of personalized medicine, the clinician should utilize individualized information and analyze all risk factors to provide the patient with evidence-based treatment options.

Novel Continuous Glucose Monitoring Metrics and Large-for-Gestational-Age Risk: An Exploratory Retrospective Cohort Study in Pregnancies with Type 1 Diabetes

Background: Continuous glucose monitoring (CGM) improves pregnancy outcomes in patients with type 1 diabetes (T1D). We aimed to assess the between-group differences in glycated hemoglobin (HbA1c) and the incidence of large-for-gestational-age (LGA) neonates in CGM and glucometer users and analyze the potential association of novel CGM metrics with LGA risk in T1D pregnancies. Materials and Methods: Our retrospective study cohort included 134 women with T1D treated with insulin pumps-75 of them used CGM and 59 patients measured their glucose concentrations using glucometers only. As part of our study, we matched the CGM users and patients who preferred the self-monitoring of blood glucose (SMBG) according to their baseline HbA1c and White's diabetes class at a 1:1 ratio. After the matching, both groups included 42 pregnancies. Results: We did not find any difference in changes in HbA1c and perinatal outcomes between CGM and SMBG users; however, we achieved a limited statistical power, and there were more cases of diabetic nephropathy in the SMBG group. Mothers of LGA infants had higher first-trimester HbA1c, time above target, and mean glucose concentrations in each trimester of pregnancy. Other CGM metrics reflecting glucose fluctuations attributed to hyperglycemia were associated with an increased risk of LGA. Despite optimal maternal HbA1c, 39% of neonates demonstrated LGA. Conclusions: Although participants reached the target HbA1c concentrations, mothers of LGA newborns had higher first-trimester HbA1c, as well as higher time above target range, higher mean glucose concentrations, and more glycemic fluctuations, suggesting that several CGM metrics associated with maternal hyperglycemia are associated with LGA in pregnancies with T1D.

Association of time in range with postoperative wound healing in patients with diabetic foot ulcers

Time in range (TIR) is a novel indicator of glycaemic control that has been reported to have an association with diabetic complications. The objective of the study was to explore the association of TIR with postoperative wound healing in patients with diabetic foot ulcers (DFUs). We retrospectively analysed the data of DFU patients who had undergone surgical treatment from 2015 to 2019. A 1:1 ratio in propensity score matching (PSM) was adopted to compare patients with TIR ≥50% with those <50%. Data were summarised using chi-squared, Fisher's exact, and Mann-Whitney U tests. Patients with TIR <50% underwent a higher rate of secondary surgery within a month (P = .032) and had a longer hospital stay (P = .045) with greater hospital charges (P < .001) than the TIR ≥50% group. Multivariate analysis revealed that TIR (P = .034), Wagner score (P = .009), diabetes treatment (P = .006), and type of surgery (P = .013) were independent risk factors for secondary surgery. Additionally, patient subgroups with TIR <50% and baseline HbA1c < 7.5% (P = .025), albumin level ≥ 30 g/L (P = .039), HDL < 1.16 (P = .021), or Wagner score ≥ 3 (P = .048) also experienced a higher incidence of secondary surgery. TIR was correlated with postoperative wound healing in patients with DFUs. Strict glycaemic targets should be established for surgical patients.

Improved HbA1c and reduced glycaemic variability after 1-year intermittent use of flash glucose monitoring

Flash glucose monitoring (FGM) was introduced in China in 2016, and it might improve HbA1c measurements and reduce glycaemic variability during T1DM therapy. A total of 146 patients were recruited from October 2018 to September 2019 in Liaocheng. The patients were randomly divided into the FGM group or self-monitoring blood glucose (SMBG) group. Both groups wore the FGM device for multiple 2-week periods, beginning with the 1st, 24th, and 48th weeks for gathering data, while blood samples were also collected for HbA1c measurement. Dietary guidance and insulin dose adjustments were provided to the FGM group patients according to their Ambulatory Glucose Profile (AGP) and to the SMBG group patients according to their SMBG measurements taken 3–4 times daily. All of the participants underwent SMBG measurements on the days when not wearing the FGM device. At the final visit, HbA1c, time in range (TIR), duration of hypoglycaemia and the number of diabetic ketoacidosis (DKA) events were taken as the main endpoints. There were no significant difference in the baseline characteristics of the two groups. At 24 weeks, the HbA1c level of the FGM group was 8.16 ± 1.03%, which was much lower than that of the SMBG group (8.68 ± 1.01%) (p = 0.003). The interquartile range (IQR), mean blood glucose (MBG), and the duration of hypoglycaemia in the FGM group also showed significant declines, compared with the SMBG group (p < 0.05), while the TIR increased in the FGM group [(49.39 ± 17.54)% vs (42.44 ± 15.49)%] (p = 0.012). At 48 weeks, the differences were more pronounced (p < 0.01). There were no observed changes in the number of episodes of DKA by the end of the study [(0.25 ± 0.50) vs (0.28 ± 0.51), p = 0.75]. Intermittent use of FGM by T1DM patients can improve their HbA1c and glycaemic control without increasing the hypoglycaemic exposure in insulin-treated individuals with type 1 diabetes in an developing country.

Type 2 diabetes mellitus in Peru: A literature review including studies at high-altitude settings

We performed a comprehensive review of recent publications about type 2 diabetes mellitus (T2DM) in Peru, including studies among people living at high altitude above the sea level. An increase in the prevalence of T2DM in Peru has been reported, the reasons are multifactorial and coinciding with the strong economic growth that our country has experienced over the last 20 years along with migration from the Andean regions to the coast and the adoption of a lifestyle that is a known to be a risk factor for obesity and insulin resistance. Scarce information is available in Peru about the prevalence of chronic complications of T2DM such as retinopathy, neuropathy, and nephropathy. There is a need for a health care plan based on early diagnosis of T2DM to reduce social and economic problems, as recommended by the WHO and the United Nations.

Usefulness of CGM-Derived Metric, the Glucose Management Indicator, to Assess Glycemic Control in Non-White Individuals With Diabetes

OBJECTIVE

To assess the relationship between the glucose management indicator (GMI) and HbA_1c in non-White individuals with diabetes.

RESEARCH DESIGN AND METHODS

We performed a retrospective analysis of continuous glucose monitoring metrics in individuals with diabetes divided by race into non-White and White cohorts.

RESULTS

We evaluated 316 individuals (non-White n = 68; White n = 248). Although GMI was not different (7.6 vs. 7.7; P = not significant) between the cohorts, HbA_1c was higher in the non-White cohort (8.7% vs. 8.1%; P = 0.004). HbA_1c higher than GMI by ≥0.5% was more frequently observed in the non-White cohort (90% vs. 75%; P = 0.02). In the non-White cohort only, duration of hypoglycemia was longer among those with HbA_1c higher than GMI by ≥0.5% compared with those with HbA_1c and GMI within 0.5%.

CONCLUSIONS

A differential relationship between HbA_1c and GMI in non-White versus White individuals with diabetes was observed. In non-White individuals, a greater difference between HbA_1c and GMI was associated with higher risk of hypoglycemia.

The management of type 1 diabetes in adults. A consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD)

The American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) convened a writing group to develop a consensus statement on the management of type 1 diabetes in adults. The writing group has considered the rapid development of new treatments and technologies and addressed the following topics: diagnosis, aims of management, schedule of care, diabetes self-management education and support, glucose monitoring, insulin therapy, hypoglycaemia, behavioural considerations, psychosocial care, diabetic ketoacidosis, pancreas and islet transplantation, adjunctive therapies, special populations, inpatient management and future perspectives. Although we discuss the schedule for follow-up examinations and testing, we have not included the evaluation and treatment of the chronic microvascular and macrovascular complications of diabetes as these are well-reviewed and discussed elsewhere. The writing group was aware of both national and international guidance on type 1 diabetes and did not seek to replicate this but rather aimed to highlight the major areas that healthcare professionals should consider when managing adults with type 1 diabetes. Though evidence-based where possible, the recommendations in the report represent the consensus opinion of the authors. Graphical abstract.

Advanced glycation end products via skin autofluorescence as potential marker of carotid atherosclerosis in patients with type 2 diabetes

BACKGROUND AND AIMS

Advanced glycation end products (AGEs) are reported to be correlated with diabetic vascular complications. This study aimed to investigate the association between AGEs and carotid atherosclerosis (CAS) as a surrogate marker of cardiovascular disease (CVD).

METHODS AND RESULTS

A total of 1006 patients with type 2 diabetes were included. CAS was defined as the presence of carotid arterial atherosclerotic plaque in any of bilateral carotid artery segments measured by ultrasonography. AGEs were measured by the noninvasive skin autofluorescence method. AGE_age index was calculated as AGEs × age/100. Patients with CAS showed a significantly higher AGE_age (P < 0.01), and the prevalence of CAS increased with ascending AGE_age levels (P for trend < 0.001). Logistic regression analysis revealed that AGE_age was significantly positively associated with odds of CAS, and the odds ratios of the presence of CAS across quartiles of AGE_age were 1.00, 3.00 [95% confidence interval (CI) 1.90-4.74], 4.04 (95%CI 2.50-6.53) and 4.99 (95%CI 2.97-8.40) for the multivariable-adjusted model (P for trend <0.001), respectively. In the fully adjusted model, each 5.0 increase in AGE_age was associated with a 0.019 mm increment in carotid intima-media thickness. Furthermore, AGE_age presented an acceptable predictive value for CAS, with an optimal cutoff point of 43.2, and the sensitivity, specificity and area under the curve (AUC) were 74.5% (95%CI 70.7-78.1%), 61.9% (95%CI 57.2-66.4%) and 0.735 (0.706-0.762), respectively.

CONCLUSION

AGE_age, the noninvasive measurement of AGEs combined with age is a promising approach for triaging patients at high risk of CVDs.

Awareness of Preconception Care and Its Related Factors Among Women of Childbearing Age with Type 1 Diabetes in the South of Saudi Arabia: A Cross-Sectional Survey Study

BACKGROUND

Pregnancies in women with type 1 diabetes mellitus (T1DM) are associated with an increased risk of poor outcomes for mothers and their infants.

OBJECTIVE

To assess the awareness of preconception care among women with T1DM and their self-management status in the southern region of Saudi Arabia.

METHODS

This study is a cross-sectional study that was done on 187 women participated of childbearing age with T1DM who were seen in diabetic centers between June 2019 and September 2020. Pre-pregnancy care and disease management were assessed via a questionnaire.

RESULTS

The prevalence of preconception awareness of diabetes management was 66.9%. Several factors significantly influenced the level of awareness, including education level (P= 0.001) and HbA1c (P= 0.014). In multivariate analysis, the lower educational level turns out to be a significant risk factor for low awareness (OR = 3.71, 95% CI [1.65, 8.31], P= 0.001). Additionally, compared to controlled DM, uncontrolled diabetes had a twofold increased risk of low awareness (OR = 2.03, 95% CI [1.08, 3.81], P= 0.027).

CONCLUSION

The awareness level was significantly correlated with a high educational level and better glycemic control. Meanwhile, it was not significantly correlated with diabetes duration.

Nursing interventions for people with type 1 diabetes and frequent hypoglycaemia

Type 1 diabetes is a lifelong condition which affects all age ranges, for reasons unknown, and the UK has one of the highest incidences of this complex condition in the world. Type 1 diabetes is caused by autoimmune damage to the insulin-producing β-cells found in the pancreatic islet cells, leading to severe insulin deficiency. People with diabetes need to achieve a target glyosylated haemoglobin level to avoid macro- and microvascular complications, but there is the associated risk of hypoglycaemic events. These can vary in severity and consequences but will likely always cause worry for the person living with diabetes. There are many risk factors and reasons to be explored when looking at hypoglycaemia. This case study explores the nursing interventions that can be safely worked through and prioritised, within the community setting, to allow people with diabetes to be safe from severe hypoglycaemia, thus improving their quality of life and safety, as well as reducing costs for the NHS.

Consensus report: definition and interpretation of remission in type 2 diabetes

Improvement of glucose levels into the normal range can occur in some people living with diabetes, either spontaneously or after medical interventions, and in some cases can persist after withdrawal of glucose-lowering pharmacotherapy. Such sustained improvement may now be occurring more often due to newer forms of treatment. However, terminology for describing this process and objective measures for defining it are not well established, and the long-term risks vs benefits of its attainment are not well understood. To update prior discussions of this issue, an international expert group was convened by the American Diabetes Association to propose nomenclature and principles for data collection and analysis, with the goal of establishing a base of information to support future clinical guidance. This group proposed 'remission' as the most appropriate descriptive term, and HbA_1c <48 mmol/mol (6.5%) measured at least 3 months after cessation of glucose-lowering pharmacotherapy as the usual diagnostic criterion. The group also made suggestions for active observation of individuals experiencing a remission and discussed further questions and unmet needs regarding predictors and outcomes of remission.

The Management of Type 1 Diabetes in Adults. A Consensus Report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD)

The American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) convened a writing group to develop a consensus statement on the management of type 1 diabetes in adults. The writing group has considered the rapid development of new treatments and technologies and addressed the following topics: diagnosis, aims of management, schedule of care, diabetes self-management education and support, glucose monitoring, insulin therapy, hypoglycemia, behavioral considerations, psychosocial care, diabetic ketoacidosis, pancreas and islet transplantation, adjunctive therapies, special populations, inpatient management, and future perspectives. Although we discuss the schedule for follow-up examinations and testing, we have not included the evaluation and treatment of the chronic microvascular and macrovascular complications of diabetes as these are well-reviewed and discussed elsewhere. The writing group was aware of both national and international guidance on type 1 diabetes and did not seek to replicate this but rather aimed to highlight the major areas that health care professionals should consider when managing adults with type 1 diabetes. Though evidence-based where possible, the recommendations in the report represent the consensus opinion of the authors.

Glucose Management Indicator for People with Type 1 Asian Diabetes Is Different from That of the Published Equation: Differences by Glycated Hemoglobin Distribution

Background: We aimed to determine whether there are racial differences in glucose management indicator (GMI) equation for Asians and propose an adjusted GMI equation specific to Asians. Methods: This was a 24-week, prospective, observational study. A total of 106 Korean subjects with type 1 diabetes was included in the analyses. Continuous glucose monitoring (CGM: Dexcom G5) data and glycated hemoglobin (HbA1c) were obtained at the end of 3 months (n = 106) and 6 months (n = 70) of use of a CGM device. Full 3-month CGM data were collected from 176 patients. Results: Linear regression analysis between HbA1c and CGM-derived mean glucose (GMI [%] = 2.814 + 0.026 × mean glucose [mg/dL], R² = 0.739, P < 0.001) showed significant correlation. An increase corresponding to each 25 mg/dL increase of mean glucose was higher with the Asian-Dexcom-specific GMI (0.7%) than with the published GMI (0.6%). The mean Asian-Dexcom-specific GMI was significantly lower than the published GMI (P = 0.022), especially in patients with HbA1c <7.0% (<6.0%: P = 0.003, 6.0%-6.9%: P = 0.001). Conclusions: The GMI equation specific for Asian Type 1 diabetes was different from the published GMI equation. For a given CGM-derived mean glucose, GMI calculated with the published equation could overestimate HbA1c in Asian subjects with HbA1c <7.0%. Although race partially explains the differences in GMI equation between published and Asian data, future research with larger databases is needed to develop a specific formula for Asian populations.

Rethinking Carbohydrate Intake and Time in Range in Children and Adolescents with Type 1 Diabetes

The aim of this study was to evaluate the association between macronutrient intake and time in range (TIR) of 70-180 mg/dL in children and adolescents with type 1 diabetes (T1D). A multi-center study recruited patients with T1D using continuous glucose monitoring (CGM) between January 2019 and January 2020 from centers across Italy. Diet intake was recorded using three-day weighed food diaries. Nutrients were evaluated as percentages of total intake. TIR was considered at target if the percentage of readings was higher than 70%. Clinical and nutritional factors associated with TIR at target were analyzed using multiple correspondence analysis and multiple logistic regression. Data from 197 participants (53% male, median age 11.6 years, median HbA1c 55.2 mmol/mol, median TIR 60%) were analyzed. Macronutrient intake was 45.9% carbohydrates, 16.9% protein, 37.3% fat, and 13.1 g/day fiber (median values). TIR > 70% was observed in 28% of participants; their diet contained more protein (17.6%, p = 0.015) and fiber (14.4 g/day, p = 0.031) than those not at target. The probability of having a TIR > 70% was significantly higher with 40-44% consumption of carbohydrates compared with 45-50% consumption of carbohydrates and with the use of a carbohydrate counting system. Based on these results, a five percent reduction in the percentage of carbohydrate intake can help children and adolescents with T1D achieve the goal of a TIR > 70%. Both a lower and higher percentage of carbohydrate intake appears to reduce the probability of reaching the target TIR > 70%. These results require validation in other populations before being used in clinical practice.

Time in range, especially overnight time in range, is associated with sudomotor dysfunction in patients with type 1 diabetes

BACKGROUND

Time in range (TIR) is advocated as key metric of glycemic control and is reported to be associated with microvascular complications of diabetes. Sudomotor dysfunction is among the earliest detectable diabetic peripheral neuropathy (DPN). We set about to research the relationship between TIR including overnight TIR and sudomotor function detected by SUDOSCAN with the intention of exploring the correlation of TIR including overnight TIR and early DPN in type 1 diabetes (T1D).

METHODS

95 patients with T1D were enrolled. TIR including nocturnal TIR of 3.9-10.0 mmol/L was evaluated with CGM. SUDOSCAN measured feet electrochemical skin conductance (FESC) and sudomotor dysfunction was defined as average FESC < 60µS. Logistic regressions were applied to examine the independent association of TIR and overnight TIR with sudomotor function.

RESULTS

The overall prevalence of sudomotor dysfunction was 28.42%. Patients with sudomotor dysfunction had significantly lower TIR for the whole recorded phase and for nighttime. The sudomotor dysfunction prevalence progressively declined with the ascending tertiles of TIR and nocturnal TIR (P for trend < 0.05). Correlation analysis showed that the relationship between nocturnal TIR and FESC was stronger than that between TIR and FESC with correlation coefficients were respectively 0.362 and 0.356 (P < 0.001). Finally, logistic regression analysis indicated the independently negative relation between TIR and nocturnal TIR and sudomotor dysfunction (P < 0.05), and the correlation between nocturnal TIR and sudomotor dysfunction was more statistically significant.

CONCLUSIONS

TIR is negatively correlated with sudomotor dysfunction in T1D independent of HbA1c. Furthermore, decreased nocturnal TIR is more closely related to the impaired function of sudomotor nerves in sweat glands.

Association of HbA1c With All-cause Mortality Across Varying Degrees of Glycemic Variability in Type 2 Diabetes

CONTEXT

The interaction of glycated hemoglobin A1c (HbA1c) and glycemic variability in relation to diabetes-related outcomes remains unknown.

OBJECTIVE

To evaluate the relationship between HbA1c and all-cause mortality across varying degrees of glycemic variability in patients with type 2 diabetes.

DESIGN, SETTING, AND PATIENTS

This was a prospective study conducted in a single referral center. Data of 6090 hospitalized patients with type 2 diabetes was analyzed. Glucose coefficient of variation [coefficient of variation (CV)] was obtained as the measure of glycemic variability by using continuous glucose monitoring for 3 days. Cox proportional hazards regression models were used to estimate hazard ratios and 95% CIs for all-cause mortality.

RESULTS

During a median follow-up of 6.8 years, 815 patients died. In patients with the lowest and middle tertiles of glucose CV, HbA1c ≥ 8.0% was associated with 136% (95% CI 1.46-3.81) and 92% (95% CI 1.22-3.03) higher risks of all-cause mortality, respectively, as compared with HbA1c 6.0%-6.9%, after adjusting for confounders. However, a null association of HbA1c with mortality was found in patients with the highest tertile of glucose CV.

CONCLUSIONS

HbA1c may not be a robust marker of all-cause mortality in patients with high degree of glycemic variability. New metrics of glycemic control may be needed in these individuals to achieve better diabetes management.

The Role of Protein and Fat Intake on Insulin Therapy in Glycaemic Control of Paediatric Type 1 Diabetes: A Systematic Review and Research Gaps

Carbohydrate counting (CHC) is the established form of calculating bolus insulin for meals in children with type 1 diabetes (T1DM). With the widespread use of continuous glucose monitoring (CGM) observation time has become gapless. Recently, the impact of fat, protein and not only carbohydrates on prolonged postprandial hyperglycaemia have become more evident to patients and health-care professionals alike. However, there is no unified recommendation on how to calculate and best administer additional bolus insulin for these two macronutrients. The aim of this review is to investigate: the scientific evidence of how dietary fat and protein influence postprandial glucose levels; current recommendations on the adjustment of bolus insulin; and algorithms for insulin application in children with T1DM. A PubMed search for all articles addressing the role of fat and protein in paediatric (sub-)populations (<18 years old) and a mixed age population (paediatric and adult) with T1DM published in the last 10 years was performed. Conclusion: Only a small number of studies with a very low number of participants and high degree of heterogeneity was identified. While all studies concluded that additional bolus insulin for (high) fat and (high) protein is necessary, no consensus on when dietary fat and/or protein should be taken into calculation and no unified algorithm for insulin therapy in this context exists. A prolonged postprandial observation time is necessary to improve individual metabolic control. Further studies focusing on a stratified paediatric population to create a safe and effective algorithm, taking fat and protein into account, are necessary.

Continuous Glucose Monitoring Time-in-Range and HbA1c Targets in Pregnant Women with Type 1 Diabetes

The CONCEPTT trial compared real-time Continuous Glucose Monitoring (RT-CGM) to capillary glucose monitoring in pregnant women with type 1 diabetes. We analyzed CGM and glycated hemoglobin (HbA_1c) measures in first (n = 221), second (n = 197), and third (n = 172) trimesters, aiming to examine target glucose attainment and associations with pregnancy outcomes. CGM targets were Time-in-range (TIR) > 70%, Time-above-range (TAR) <25%, and Time-below-range (TBR) < 4%, and HbA_1c targets < 6.5% (National Institute for Health and Care Excellence [NICE]) and HbA_1c < 6.0% in second and third trimesters (American Diabetes Association [ADA]). TIR/TAR/TBR targets were achieved by 7.7/14.5/30.3% participants in first, 10.2/14.2/52.8% in second, and 35.5/37.2/52.9% in third trimesters. CGM target attainment was low but increased during pregnancy and with RT-CGM use. In the adjusted analyses, achieving TBR target was associated with a higher risk of pre-eclampsia and neonatal hypoglycemia. ADA HbA_1c target attainment was low and unchanged during pregnancy (23.5/27.9/23.8%) but increased with RT-CGM use. In the adjusted analyses, HbA_1c target attainment was associated with a lower risk of preterm birth, large-for-gestational age and neonatal hypoglycemia. We conclude that CONCEPTT trial participants had a low rate of CGM and of HbA_1c target attainment. Attainment of CGM and NICE HbA_1c targets increased throughout gestation and all targets (both NICE/ADA HbA_1c and CGM) were more likely to be achieved by RT-CGM users, at 34 weeks' gestation. ADA HbA_1c target achievement was independently associated with better perinatal outcomes, while the independent association of TBR target achievement with increased risk warrants further study. ClinicalTrials.gov Registration Identifier NCT01788527.

Assessment of Hyperglycemia, Hypoglycemia and Inter-Day Glucose Variability Using Continuous Glucose Monitoring among Diabetic Patients on Chronic Hemodialysis

Continuous glucose monitoring (CGM) facilitates the assessment of short-term glucose variability and identification of acute excursions of hyper- and hypo-glycemia. Among 37 diabetic hemodialysis patients who underwent 7-day CGM with the iPRO2 device (Medtronic Diabetes, Northridge, CA, USA), we explored the accuracy of glycated albumin (GA) and hemoglobin A1c (HbA1c) in assessing glycemic control, using CGM-derived metrics as the reference standard. In receiver operating characteristic (ROC) analysis, the area under the curve (AUC) in diagnosing a time in the target glucose range of 70–180 mg/dL (TIR^70–180) in <50% of readings was higher for GA (AUC: 0.878; 95% confidence interval (CI): 0.728–0.962) as compared to HbA1c (AUC: 0.682; 95% CI: 0.508–0.825) (p < 0.01). The accuracy of GA (AUC: 0.939; 95% CI: 0.808–0.991) in detecting a time above the target glucose range > 250 mg/dL (TAR^>250) in >10% of readings did not differ from that of HbA1c (AUC: 0.854; 95% CI: 0.699–0.948) (p = 0.16). GA (AUC: 0.712; 95% CI: 0.539–0.848) and HbA1c (AUC: 0.740; 95% CI: 0.570–0.870) had a similarly lower efficiency in detecting a time below target glucose range < 70 mg/dL (TBR^<70) in >1% of readings (p = 0.71). Although the mean glucose levels were similar, the coefficient of variation of glucose recordings (39.2 ± 17.3% vs. 32.0 ± 7.8%, p < 0.001) and TBR^<70 (median (range): 5.6% (0, 25.8) vs. 2.8% (0, 17.9)) were higher during the dialysis-on than during the dialysis-off day. In conclusion, the present study shows that among diabetic hemodialysis patients, GA had higher accuracy than HbA1c in detecting a 7-day CGM-derived TIR^70–180 < 50%. However, both biomarkers provided an imprecise reflection of acute excursions of hypoglycemia and inter-day glucose variability.

Consensus Report: Definition and Interpretation of Remission in Type 2 Diabetes

Improvement of glucose levels into the normal range can occur in some people living with diabetes, either spontaneously or after medical interventions, and in some cases can persist after withdrawal of glucose-lowering pharmacotherapy. Such sustained improvement may now be occurring more often due to newer forms of treatment. However, terminology for describing this process and objective measures for defining it are not well established, and the long-term risks versus benefits of its attainment are not well understood. To update prior discussions of this issue, an international expert group was convened by the American Diabetes Association to propose nomenclature and principles for data collection and analysis, with the goal of establishing a base of information to support future clinical guidance. This group proposed "remission" as the most appropriate descriptive term, and HbA1c <6.5% (48 mmol/mol) measured at least 3 months after cessation of glucose-lowering pharmacotherapy as the usual diagnostic criterion. The group also made suggestions for active observation of individuals experiencing a remission and discussed further questions and unmet needs regarding predictors and outcomes of remission.

Continuous glucose monitoring in an end-stage renal disease patient with diabetes receiving hemodialysis

Diabetes is the leading cause of end-stage renal disease (ESRD) and contributes to heightened morbidity and mortality in dialysis patients. Given that ESRD patients are susceptible to hypoglycemia and hyperglycemia via multiple pathways, adequate glycemic monitoring and control is a cornerstone in diabetic kidney disease management. In ESRD, existing glycemic metrics such as glycated hemoglobin, self-monitored blood glucose, fructosamine, and glycated albumin have limitations in accuracy, convenience, and accessibility. In contrast, continuous glucose monitoring (CGM) provides automated, less invasive glucose measurements and more comprehensive glycemic data versus conventional metrics. Here, we report a 48-year-old male with ESRD due to diabetes receiving thrice-weekly hemodialysis who experienced decreased patient-burden, greater glucose monitoring adherence, improved glycemic parameters, and reduction in hypoglycemia after transitioning to CGM. Through this case, we discuss how CGM is a practical, convenient patient-centered tool that may improve metabolic outcomes and quality of life in ESRD patients with diabetes.

Hemoglobin A1c Patterns of Youth With Type 1 Diabetes 10 Years Post Diagnosis From 3 Continents

OBJECTIVES

Distinct hemoglobin A1c (HbA1c) trajectories during puberty are identified in youth with established type 1 diabetes (T1D). We used data from 3 international registries to evaluate whether distinct HbA1c trajectories occur from T1D onset.

METHODS

Participants were <18 years old at diagnosis with at least 1 HbA1c measured within 12 months post diagnosis, along with ≥3 duration-year-aggregated HbA1c values over 10 years of follow-up. Participants from the Australasian Diabetes Data Network (n = 7292), the German-Austrian-Luxembourgian-Swiss diabetes prospective follow-up initiative (Diabetes Patienten Verlaufsdokumentation) (n = 39 226) and the US-based Type 1 Diabetes Exchange Clinic Registry (n = 3704) were included. With group-based trajectory modeling, we identified unique HbA1c patterns from the onset of T1D.

RESULTS

Five distinct trajectories occurred in all 3 registries, with similar patterns of proportions by group. More than 50% had stable HbA1c categorized as being either low stable or intermediate stable. Conversely, ∼15% in each registry were characterized by stable HbA1c >8.0% (high stable), and ∼11% had values that began at or near the target but then increased (target increase). Only ∼5% of youth were above the target from diagnosis, with an increasing HbA1c trajectory over time (high increase). This group differed from others, with higher rates of minority status and an older age at diagnosis across all 3 registries (P ≤ .001).

CONCLUSIONS

Similar postdiagnostic HbA1c patterns were observed across 3 international registries. Identifying the youth at the greatest risk for deterioration in HbA1c over time may allow clinicians to intervene early, and more aggressively, to avert increasing HbA1c.

The relationship between glycosylated hemoglobin, time-in-range and glycemic variability in type 1 diabetes patients under flash glucose monitoring

OBJECTIVES

Flash glucose monitoring in patients with type 1 diabetes provides new glucometric data that allow for the assessment of glycemic control beyond HbA_1c. The objective of the study was to evaluate the relationship between HbA_1c, time-in-range (TIR) and glycemic variability in a cohort of paediatric and adult patients with type 1 diabetes and treatment with flash glucose monitoring.

MATERIAL AND METHODS

This was a cross-sectional study in 195 patients with type 1 diabetes (42.6% females, 70 paediatric, 26.2% continuous subcutaneous insulin infusion, 28.7% coefficient of variation [CV]≤36%) in intensive treatment and flash glucose monitoring. Clinical, analytical and glucometric data were evaluated.

RESULTS

The relationship between the TIR and HbA_1c showed a strong negative linear correlation (R=-0.746; R²=0.557; P<.001), modified in those patients with CV≤36% (R=-0.852; R²=0.836) compared to CV>36% (R=-0.703; R²=0.551). A similar correlation was found when evaluating the TIR and the Glucose Management Indicator (R=-0.846; R²=0.715; P<.001); in patients with CV≤36% (R=-0.980; R²=0.960) versus CV>36% (R=-0.837; R²=0.701); P<.001. Both correlations remained stable in the paediatric population (R=-0.724; R²=0.525; P<.001) and adults (R=-0.706; R²=0.498; P<.001) and by type of treatment: multiple doses of insulin (R=-0.747; R²=0.558; P<.001) and continuous subcutaneous insulin infusion (R=-0.711; R²=0.506; P<.001). In a multiple regression analysis evaluating HbA_1c as dependent variable, the only parameters that maintained statistical significance were the TIR (β=-0,031; P<.001), CV (β=0.843; P<.05) and TIR-CV interaction (β=-0.017; P<.01).

CONCLUSIONS

The glycemic variability defined by the CV modifies the relationship between the TIR and HbA_1c/Glucose Management Indicator and should be taken into account when individualising TIR targets, regardless of age or the type of treatment used.

Assessment of metabolic control and use of flash glucose monitoring systems in a cohort of pediatric, adolescents, and adults patients with Type 1 diabetes

PURPOSE

Flash glucose monitoring (FGM) in patients with type 1 diabetes (DM1) provides glucometric data that allow assessing glycemic control beyond HbA1c. The objective of this study was to evaluate metabolic control and use of FGM in a cohort of the pediatric and adult population with DM1.

MATERIAL AND METHODS

A cross-sectional study of patients with DM1 and FGM. Data on the use of the system and metabolic control were evaluated, carrying out a comparative study between different age ranges, ≤12 years; 13-19 years, 20-25 years, and ≥26 years.

RESULTS

One hundred and ninety-five patients have included: 35.9% children and adolescents (≤19 years), 42.6% female, 26.2% in treatment with an insulin pump. Mean age was 28.5 ± 15.9 years, mean duration of diabetes 13.7 ± 11.0 years, and mean HbA1c 7.1 ± 0.9% (54 ± 6 mmol/l). Average daily FGM scans were 11.1 ± 6.7. Mean glucose was 162 ± 35 mg/dl, mean standard deviation (SD) 66.1 ± 20.4 mg/dl, mean coefficient of variation 41.4 ± 7.9%, mean time in range (TIR) 58.8 ± 17.0%, mean time above range 33.7 ± 17.6% and mean time below range 7.5 ± 5.8%. The pediatric group showed higher TIR, lower HbA1c, lower glycemic variability, lower mean glucose, and higher use of the device than the adult population. In the entire cohort, the device scans showed a negative quadratic correlation with HbA1c, mean glucose, SD, and age and a positive quadratic correlation with TIR.

CONCLUSIONS

Children under 12 years showed the best metabolic control and the most frequent use of the device. Metabolic control deteriorates with age. The greater number of device scans was in correlation with better metabolic control in all age groups.

Time-in-range for monitoring glucose control: Is it time for a change?

The HbA1c value has been the gold standard for evaluating glucose control for decades. However, it has limitations such as the lack of information on glycemic variability or the risk of hypoglycemia. The increasing use of continuous glucose monitoring has provided patients and healthcare professionals with a range of useful metrics for the management of diabetes. Among them, Time in Range (TIR) is a simple and intuitive metric that gives information regarding the quality of glucose control. It is defined as the time spent in an individual's target glucose range. TIR is strongly correlated with HbA1c, and it has been linked to the risk of developing microvascular and macrovascular complications. The International Consensus on Time in Range has recently set targets for different diabetes populations. For the majority of people with type 1 or type 2 diabetes, a TIR (70-180 mg/dL or 3.9-10.0 mmol/L) of >70%, a time below range (TBR) <70 mg/dL (<3.9 mmol/L) of <4% and a TBR <54 (<3.0 mmol/L) of <1% are recommended. In this review, we address the latest evidence for the use of TIR as an essential parameter in the management of diabetes.

Relationships between HbA1c and continuous glucose monitoring metrics of glycaemic control and glucose variability in a large cohort of children and adolescents with type 1 diabetes

AIMS

To evaluate the relationships between HbA1c and Continuous Glucose Monitoring (CGM) metrics in children/adolescents with Type 1 Diabetes (T1D).

METHODS

HbA1c and real-life CGM data of the 12 weeks preceding its measurement were retrospectively collected from 654 children/adolescents with T1D. The relationships between HbA1c and CGM metrics were assessed by Spearman correlation coefficient. Participants were categorized into groups based on HbA1c and CGM metrics values. ANOVA was run across HbA1c and CGM metrics groups in the entire study population and in subjects stratified by CGM type, insulin therapy, age and puberty.

RESULTS

HbA1c was positively correlated with mean glucose, SD, %TAR > 180 mg/dL, %TAR > 250 mg/dL, HBGI and negatively with %TIR, %TBR and %time < 54 mg/dL. HbA1c-based groups were significantly associated with these metrics, but for each group their value widely ranged with a substantial overlap between them. HbA1c and HbA1c-based groups were not associated with %CV and LBGI, as well as %CV and LBGI-based groups had not significantly different HbA1c. Comparable results were found analysing subjects according to age, type of CGM, insulin therapy and puberty.

CONCLUSIONS

The relationships between HbA1c and CGM metrics described in this cohort of paediatric subjects with T1D support the importance of the evaluation of these metrics, in particular %CV and LBGI, independently of HbA1c value.