Impact of visit-to-visit glycemic variability on the risks of macrovascular and microvascular events and all-cause mortality in type 2 diabetes: the ADVANCE trial

Effects of Insulin Degludec and Insulin Glargine U300 on Day-to-Day Fasting Plasma Glucose Variability in Individuals with Type 1 Diabetes: A Multicenter, Randomized, Crossover Study (Kobe Best Basal Insulin Study 2)

INTRODUCTION

Administered basal insulin markedly influences the fasting plasma glucose (FPG) level of individuals with type 1 diabetes. Insulin degludec (IDeg) and insulin glargine U300 (IGlar U300) are now available as ultra-long-acting insulin formulations, but whether or how their glucose-stabilizing effects differ remains unclear. We will compare the effects of these basal insulins on parameters related to blood glucose control, with a focus on day-to-day glycemic variability, in individuals with type 1 diabetes treated with multiple daily injections.

METHODS

A multicenter, randomized, open-label, crossover, comparative study (Kobe Best Basal Insulin Study 2) will be performed at 13 participating institutions in Japan. A total of 46 C-peptide-negative adult outpatients with type 1 diabetes will be randomly assigned 1:1 by a centralized allocation process to IGlar U300 (first period)/IDeg (second period) or IDeg (first period)/IGlar U300 (second period) groups, in which subjects will be treated with the corresponding basal insulin for consecutive 4-week periods. The basal insulin will be titrated to achieve an FPG of less than 130 mg/dL initially and then less than 110 mg/dL if feasible. In the last week of each period, plasma glucose will be determined seven times a day by self-monitoring of blood glucose (SMBG) and intraday and day-to-day glucose excursions will be determined by flash glucose monitoring (FGM). The primary end point is comparison of day-to-day glycemic variability as evaluated by the standard deviation (SD) of FPG during the last week of each treatment period. Secondary end points include the coefficient of variance of FPG, the frequency of severe hypoglycemia as evaluated by SMBG, the duration of hypoglycemia as evaluated by FGM, intraday glycemic variability calculated from both SMBG and FGM data, and the administered insulin dose.

PLANNED OUTCOMES

The results of the study will be submitted for publication in a peer-reviewed journal to report differences in the effects of two ultra-long-acting basal insulins, IDeg and IGlar U300.

CONCLUSION

This head-to-head comparison will be the first study to compare the effects of IDeg and IGlar U300 on day-to-day FPG variability in C-peptide-negative individuals with type 1 diabetes.

TRIAL REGISTRATION

Registered in University Hospital Medical Information Network (UMIN) Clinical Trials Registry as 000029630 on 20 June 2017.

FUNDING

Novo Nordisk Pharma Ltd.

Glycemic Variability: How to Measure and Its Clinical Implication for Type 2 Diabetes

Glycated hemoglobin A1c (A1C) levels have traditionally been the gold standard for assessing glycemic control and treatment efficacy in patients with type 2 diabetes. However, A1C does not take into account fluctuations in blood glucose levels known as glycemic variability (GV). In recent years, GV has become increasingly clinically relevant, because of a better understanding of the need to reach target A1C while avoiding hypoglycemia. GV relates to both hyperglycemia and hypoglycemia, and has been associated with poorer quality of life. Diabetes treatments targeting multiple pathophysiological mechanisms are most beneficial in controlling A1C and reducing GV. In clinical trials, a number of metrics are used to measure GV, many of which are not well understood in the clinical practice. Until a gold standard metric for GV is established, the variety of measurements available may confound the choice of an optimal treatment for an individual patient.

Natural history and risk factors for diabetic kidney disease in patients with T2D: lessons from the AMD-annals

The Associazione Medici Diabetologi (AMD) annals initiative is an ongoing observational survey promoted by AMD. It is based on a public network of about 700 Italian diabetes clinics, run by specialists who provide diagnostic confirmation and prevention and treatment of diabetes and its complications. Over the last few years, analysis of the AMD annals dataset has contributed several important insights on the clinical features of type-2 diabetes kidney disease and their prognostic and therapeutic implications. First, non-albuminuric renal impairment is the predominant clinical phenotype. Even though associated to a lower risk of progression compared to overt albuminuria, it contributes significantly to the burden of end-stage renal disease morbidity. Second, optimal blood pressure control provides significant but incomplete renal protection. It reduces albuminuria but there may be a J curve phenomenon with eGFR at very low blood pressure values. Third, hyperuricemia and diabetic hyperlipidemia, namely elevated triglycerides and low HDL cholesterol, are strong independent predictors of chronic kidney disease (CKD) onset in diabetes, although the pathogenetic mechanisms underlying these associations remain uncertain. Fourth, the long-term intra-individual variability in HbA1c, lipid parameters, uric acid and blood pressure plays a greater role in the appearance and progression of CKD than the absolute value of each single variable. These data help clarify the natural history of CKD in patients with type 2 diabetes and provide important clues for designing future interventional studies.

Variability in metabolic parameters and risk of dementia: a nationwide population-based study

Background

Variability in biological parameters has been reported to be associated with adverse health outcomes. We aimed to investigate the composite effect of the visit-to-visit variability in blood pressure, glucose, cholesterol, and body mass index on the risk of dementia.

Methods

A population-based cohort study including 2,930,816 subjects without a history of dementia, hypertension, diabetes mellitus, and dyslipidemia who underwent ≥ 3 health examinations was performed. The coefficient of variation (CV), standard deviation, and variability independent of the mean were calculated as variability indices. High variability was defined as having values in the highest quartile for each parameter.

Results

A total of 32,901 (1.12%) participants developed dementia, of which 74.4% and 11.0% were attributable to Alzheimer’s disease and vascular dementia, respectively, during the median follow-up of 5.5 years. Individuals with higher variability of each parameter were at higher risk of future dementia. In the multivariable adjusted model, the hazard ratios and 95% confidence intervals of all-cause dementia were 1.22 (1.19–1.26) for one parameter, 1.39 (1.35–1.43) for two parameters, 1.54 (1.48–1.60) for three parameters, and 1.73 (1.60–1.88) for four parameters compared with subjects having no parameters of high variability measured as the CV. Consistent results were noted for Alzheimer’s disease and vascular dementia, using other indices of variability and in various sensitivity and subgroup analyses.

Conclusions

There was a linear association between the number of high variability parameters and risk of dementia. Reducing variability of metabolic parameters would be a target to preserve cognitive reserve in the general population.

Electronic supplementary material

The online version of this article (10.1186/s13195-018-0442-3) contains supplementary material, which is available to authorized users.

Glycemic Variation and Cardiovascular Risk in the Veterans Affairs Diabetes Trial

OBJECTIVE

There is uncertainty about the importance of glycemic variability in cardiovascular complications in patients with type 2 diabetes. Using the Veterans Affairs Diabetes Trial (VADT), we investigated the association between variation in fasting glucose and glycated hemoglobin (HbA_1c) over time and the incidence of cardiovascular disease (CVD) and assessed whether this is influenced by intensive or standard glycemic control.

RESEARCH DESIGN AND METHODS

During the VADT, fasting glucose and HbA_1c were measured every 3 months for up to 84 months in 1,791 individuals. Variability measures included coefficient of variation (CV) and average real variability (ARV) for fasting glucose and HbA_1c. Overall mean glucose and HbA_1c measures as well as their maximum and the most recent measurement were also examined.

RESULTS

Variability measures (CV and ARV) of fasting glucose were significantly associated with CVD even after adjusting for other risk factors, including mean fasting glucose. When considering separately groups receiving intensive and standard glycemic control, this relationship was evident in the intensive treatment group but not in the standard group. Additional adjustment for severe hypoglycemic episodes did not alter the relationship between fasting glucose variability and CVD. Interestingly, no HbA_1c measures were associated with CVD after adjusting for multiple baseline risk factors.

CONCLUSIONS

Our analysis indicates that in the VADT, variability of fasting glucose plays a role in the development of CVD complications beyond the influence of standard fasting glucose measures. The adverse consequences of fasting glucose variability on CVD appear greatest in those receiving intensive glucose control.

Type 2 Diabetes and Glycemic Variability: Various Parameters in Clinical Practice

It has become possible to measure blood glucose levels continuously from 24 h to approximately 2 weeks due to the recent development of relevant devices such as continuous glucose monitoring and flash glucose monitoring systems. This has enabled not only medical professionals but also patients to monitor details of glycemic variability (GV) which was not possible in the past. Details of GV for both short and intermediate periods can now be obtained, and it is important in patient care to appropriately evaluate the data obtained. Types of GV in terms of time frame vary from short-term to long-term. Several studies reported that long-term GV was related to micro- and macro-angiopathies in patients with type 2 diabetes mellitus (T2DM). However, there are still unknown aspects regarding the relationships of various durations of GV with prognosis. Further clinical trials are required to examine the mechanism of GV and to evaluate whether GV can be a valuable therapeutic target in treatment of patients with T2DM.

Haemoglobin A1c variability as an independent correlate of atherosclerosis and cardiovascular disease in Chinese type 2 diabetes

OBJECTIVE

To examine the association between haemoglobin A1c variability and macrovascular complication in type 2 diabetes.

METHODS

We retrospectively enrolled 5278 diabetes patients with no history of cardiovascular disease and atherosclerosis by ultrasound at their first visit to the hospital from 1999 to 2010. Patients had a median of 4 haemoglobin A1c (range = 3-9) measurements during follow-up. Average haemoglobin A1c and haemoglobin A1c variability were calculated as intra-individual mean, standard deviation, coefficient of variation and adjusted standard deviation. Cardiovascular disease events and ultrasound results were re-evaluated from the medical history at the end of the study.

RESULTS

A total of 972 patients had macrovascular complication. Compared to those without atherosclerosis/cardiovascular disease (n = 4306), haemoglobin A1c intra-individual mean and haemoglobin A1c variability levels were significantly higher in patients with macrovascular complication ( p < 0.001). Multivariable logistic regression analysis showed that haemoglobin A1c variability was associated with macrovascular complication. Moreover, 488 patients with only atherosclerosis had significantly higher haemoglobin A1c intra-individual mean and haemoglobin A1c variability values than those without atherosclerosis/cardiovascular disease ( p < 0.001), but in 484 patients with cardiovascular disease incidents, only higher haemoglobin A1c intra-individual mean level was found ( p = 0.004).

CONCLUSIONS

In Chinese type 2 diabetes, haemoglobin A1c variability was associated with macrovascular complication. Long-term stabilization of glucose is important in diabetes management, especially in the early stage of atherosclerosis.

Haemoglobin A1c variability is a strong, independent predictor of all-cause mortality in patients with type 2 diabetes

AIMS

To evaluate various measures of haemoglobin (Hb) A1c variability, compared with average HbA1c, as independent predictors of mortality.

MATERIALS AND METHODS

The Renal Insufficiency And Cardiovascular Events Italian multicentre study enroled 15 733 patients with type 2 diabetes from 19 diabetes clinics during 2006-2008. A total of 3 to 5 HbA1c measures, obtained during the 2-year period before enrolment, were available from 9 centres (8290 patients) and were used to calculate average HbA1c (HbA1c -MEAN) and HbA1c variability, measured as intra-individual standard deviation (HbA1c-SD), SD adjusted for the number of HbA1c assessments (HbA1c-AdjSD) and coefficient of variation (HbA1c-CV), that is, the HbA1c-SD to HbA1c-MEAN ratio. Vital status on October 31, 2015 was retrieved for 8252 patients (99.5%).

RESULTS

The measures of HbA1c variability increased according to quartiles of HbA1c-MEAN and vice versa. HbA1c-MEAN and measures of HbA1c variability were associated with all-cause mortality; however, the strength of association of HbA1c-MEAN was lower than that of HbA1c -SD, HbA1c-CV or HbA1c-AdjSD, and disappeared after adjusting for confounders and any of the measures of HbA1c variability. Mortality increased with quartiles of HbA1c-MEAN, HbA1c -SD, HbA1c-CV and HbA1c-AdjSD, but only the association with HbA1c variability measures remained after adjustment for confounders and/or each other measure. In the fully adjusted model, mortality risk was lower for HbA1c-SD below the median and higher for HbA1c-SD above the median, regardless of whether HbA1c-MEAN was below or above the median. Conclusions HbA1c variability is a strong, independent predictor of all-cause mortality in type 2 diabetes and appears to be even more powerful than average HbA1c in predicting mortality.

Visit-to-visit HbA1c variability is inversely related to baroreflex sensitivity independently of HbA1c value in type 2 diabetes

BACKGROUND

The relationship between long-term glycemic variability (GV) represented by visit-to-visit HbA1c variability and baroreflex sensitivity (BRS) in type 2 diabetes mellitus (T2DM) has not been clarified by previous literature. The present study is the first to examine the relationships between visit-to-visit HbA1c variability and BRS.

METHODS

This retrospective study initially analyzed data on 94 patients with T2DM. Visit-to-visit HbA1c variability was evaluated using the intrapersonal coefficient of variation (CV), standard deviation (SD), and adjusted SD of 8 or more serial measurements of HbA1c during a 2-year period. The BRS was analyzed using the sequence method. Short-term GV was assessed by measuring the glucose CV during 24-h continuous glucose monitoring (CGM). The primary objective was to determine if there was a relationship between visit-to-visit HbA1c variability (HbA1c CV) and BRS. Secondary objectives were to examine the relationship between other variables and BRS and the respective and combined effects of long-term GV (HbA1c CV) and short-term GV (CGM CV) on BRS.

RESULTS

A total of 57 patients (mean age 67.2 ± 7.7 years, mean HbA1c 7.3 ± 1.0%) who met this study's inclusion criteria were finally analyzed. In the univariate analysis, HbA1c CV (r = - 0.354, p = 0.007), HbA1c SD (r = - 0.384, p = 0.003), and adjusted HbA1c SD (r = - 0.391, p = 0.003) were significantly related to low levels of BRS. Multiple regression analysis showed that HbA1c CV, HbA1c SD, and adjusted HbA1c SD were inversely related to BRS. Furthermore, although the increase in either long-term GV (HbA1c CV) or short-term GV (CGM CV) as determined by 24-h CGM was inversely correlated with BRS, additional reductions in BRS were not shown in participants with both HbA1c CV and CGM CV values above the median.

CONCLUSIONS

Visit-to-visit HbA1c variability was inversely related to BRS independently of the mean HbA1c in patients with T2DM. Therefore, visit-to-visit HbA1c variability might be a marker of reduced BRS in T2DM.

Prognostic impact of HbA1c variability on long-term outcomes in patients with heart failure and type 2 diabetes mellitus

Background

The prognostic impact of long-term glycemic variability on clinical outcomes in patients with heart failure (HF) and type 2 diabetes mellitus (T2DM) remains unclear. We determined and compared hemoglobin A1c (HbA1c) variability and clinical outcomes for patients with HF with preserved ejection fraction (HFpEF), HF with mid-range ejection fraction (HFmrEF) and HF with reduced ejection fraction (HFrEF) in a prospective longitudinal study.

Methods

Patients with HF and T2DM, undergone 3 or more HbA1c determinations during the first 18 months, were then followed for 42 months. The primary outcome was death from any cause. Secondary outcome was composite endpoints with death and HF hospitalization. Cox proportional hazards models were used to compare outcomes for patients with HFpEF, HFmrEF and HFrEF.

Results

Of 902 patients enrolled, 32.2% had HFpEF, 14.5% HFmrEF, and 53.3% HFrEF. During 42 months of follow-up, 270 (29.9%) patients died and 545 (60.4%) patients experienced composite endpoints of death and HF readmission. The risk of all-cause death or composite endpoints was lower for HFpEF than HFrEF. Moreover, higher HbA1c variability was associated with higher all-cause mortality or composite endpoints and HbA1c variability was an independent predictor of all-cause mortality or composite endpoints, regardless of EF.

Conclusions

This prospective longitudinal study showed that the all-cause death and composite events was lower for HFpEF than HFrEF. HbA1c variability was independently and similarly predictive of death or combined endpoints in the three HF phenotypes.

Electronic supplementary material

The online version of this article (10.1186/s12933-018-0739-3) contains supplementary material, which is available to authorized users.

Mean HbA1c, HbA1c variability, and mortality in people with diabetes aged 70 years and older: a retrospective cohort study

BACKGROUND

Glycaemic targets for older people have been revised in recent years because of concern that more stringent targets are associated with increased mortality. We aimed to investigate the association between glycaemic control (mean HbA_1c) and variability (variability of HbA_1c over time) and mortality in older people with diabetes.

METHODS

We did a 5-year retrospective cohort study using The Health Improvement Network database, which includes data from 587 UK primary care practices. We included patients of either sex who were aged 70 years and older with type 1 or type 2 diabetes. The primary outcome was time to all-cause mortality. Our primary exposure variables were mean HbA_1c and variability of HbA_1c over time. The observation included a 4-year run-in period (from 2003) as a baseline, with a 5-year follow-up (from 2007 to 2012). We assessed mean HbA_1c in three models: a baseline mean HbA_1c for 2003-06 (model 1), the mean across the whole follow-up period (model 2), and a time-varying yearly updated mean (model 3). A variability score (from 0 [low] to 100 [high]) was calculated on the basis of number of changes in HbA_1c of 0·5% (5·5 mmol/mol) or more from 2003 to 2012 or to the point of mortality, based on changes in the annual mean as per each model with a minimum of six readings.

FINDINGS

The cohort consisted of 54 803 people, of whom 17 680 (8614 [30·7%] of 28 017 women and 9066 [33·8%] of 26 786 men) died during the observation period. The overall mortality rate was 77 per 1000 person-years (73 per 1000 person-years for women and 80 per 1000 person-years for men). The data showed a J-shaped distribution for mortality risk in both sexes, with significant increases with HbA_1c values greater than 8% (64 mmol/mol) and less than 6% (42 mmol/mol), although excess mortality risk was non-significant in model 1 for men at HbA_1c values of 8% (64 mmol/mol) to less than 8·5% (<69 mmol/mol) and in models 1 and 3 for both sexes assessed individually at HbA_1c values less than 6% (42 mmol/mol). Mortality increased substantially with increasing HbA_1c variability in all models (overall and for both sexes). For the model 2 HbA_1c measure, the adjusted hazard ratios comparing patients with a glycaemic variability score of more than 80 to 100 with those with a score of 0 to 20 were 2·47 (95% CI 2·08-2·93) for women and 2·21 (1·87-2·61) for men. Fitting the mean HbA_1c models with the glycaemic variability score altered the risk distribution; this observation was most marked in the model 2 analysis, in which a significant increased risk was only apparent with HbA_1c values greater than 9·5% (80 mmol/mol) in women and 9% (75 mmol/mol) in men.

INTERPRETATION

Both low and high levels of glycaemic control were associated with an increased mortality risk, and the level of variability also seems to be an important factor, suggesting that a stable glycaemic level in the middle range is associated with lower risk. Glycaemic variability, as assessed by variability over time in HbA_1c, might be an important factor in understanding mortality risk in older people with diabetes.

FUNDING

King's College London and Diabetes Frail.

Optimal cutoff values of fasting plasma glucose (FPG) variability for detecting retinopathy and the threshold of FPG levels for predicting the risk of retinopathy in type 2 diabetes: A longitudinal study over 27 years

AIMS

To determine the cutoff values of fasting plasma glucose (FPG) variability for detecting retinopathy and examine the threshold of FPG levels for predicting retinopathy incidence in type 2 diabetes.

METHODS

Subjects comprised 170 patients with type 2 diabetes who had no retinopathy at their first visit, and continuously visited thereafter for 27 years. Retinopathy was evaluated by ophthalmologists at least annually.

RESULTS

114 patients developed retinopathy. 46 of them had advanced retinopathy. The optimal cutoff values of intrapersonal mean and standard deviation (SD) of FPG over 27 years and intrapersonal mean HbA1c from the initial measurement to the last visit for detecting retinopathy were 7.4 mmol/L, 1.4 mmol/L, and 7.2% (56 mmol/mol), respectively. Similarly, for advanced retinopathy, 7.7 mmol/L, 1.9 mmol/L, and 7.5% (59 mmol/mol), respectively. Hazard ratios of deciles of intrapersonal mean FPG (mmol/L) during the initial 2 years for retinopathy incidence significantly increased from eighth-decile (6.9-7.4), and were sharply elevated from ninth-decile (7.4-8.7).

CONCLUSIONS

Our study provides new cutoff values for FPG variability. Cutoff values of FPG and HbA1c were slightly higher than recommended targets of the current guideline. The threshold of FPG levels (6.9 mmol/L) is proposed to predict retinopathy incidence during the subsequent 25 years.

HbA1c variability and diabetic peripheral neuropathy in type 2 diabetic patients

BACKGROUND

Diabetic complications may be associated with impaired time-dependent glycemic control. Therefore, long-term glycemic variability, assessed by variations in haemoglobin A1c (HbA1c), may be a potential risk factor for microvascular complications, such as diabetic peripheral neuropathy (DPN). We investigated the association of HbA1c variability with DPN in patients with type 2 diabetes.

METHODS

In this cross-sectional study, 563 type 2 diabetic patients who had been screened for DPN and undergone quarterly HbA1c measurements during the year preceding enrolment were recruited. DPN was confirmed in patients displaying both clinical manifestations of neuropathy and abnormalities in a nerve conduction evaluation. HbA1c variability was assessed by the coefficient of variation of HbA1c (CV-HbA1c), and the mean of HbA1c (M-HbA1c) was calculated. In addition, medical history and clinical data were collected.

RESULTS

Among the recruited patients, 18.1% (n = 102) were found to have DPN, and these patients also presented with a higher CV-HbA1c than the patients without DPN (p < 0.001). The proportion of patients with DPN increased significantly from 6.9% in the first to 19.1% in the second and 28.5% in the third tertile of CV-HbA1c (p for trend < 0.001). After adjusting for initial HbA1c, M-HbA1c and other clinical factors via multiple logistic regression analysis, the odds ratios (ORs) for DPN in the second and third versus those in the first CV-HbA1c tertile were 3.61 (95% CI 1.62-8.04) and 6.48 (2.86-14.72), respectively. The area under the receiver operating characteristic (ROC) curve of CV-HbA1c was larger than that of M-HbA1c, at 0.711 (95% CI 0.659-0.763) and 0.662 (0.604-0.721), respectively. ROC analysis also revealed that the optimal cutoff value of CV-HbA1c to indicate DPN was 15.15%, and its corresponding sensitivity and specificity were 66.67% and 65.73%, respectively.

CONCLUSIONS

Increased HbA1c variability is closely associated with DPN in type 2 diabetic patients and could be considered as a potent indicator for DPN in these patients.

Long-term study of the association of adipokines and glucose variability with diabetic complications

BACKGROUND/AIMS

Recent studies have suggested an important role of adipokines in the development of insulin resistance and diabetes mellitus. The clinical relevance of adipokines on long-term outcomes in patients with diabetes and chronic kidney disease is uncertain. The purpose of this study was to identify a predictable factor in patients with long-term diabetic complications.

METHODS

A total of 161 diabetic individuals were followed-up from 2002 to 2013. Circulating plasma levels of adiponectin, glypican-4, irisin, visfatin, and visit-to-visit glucose variability were measured in diabetic patients. Associations among adipokines and variable metabolic parameters and microvascular, and macrovascular complications were evaluated.

RESULTS

Plasma adiponectin and glypican-4 levels were significantly increased in patients with renal insufficiency. These adipokines were negatively associated with estimated glomerular filtration rate and positively associated with urinary albumin excretion. The relative risk of renal progression to dialysis increased independently with increasing level of adiponectin. Glypican-4 and visfatin were not predictive of any microvascular or macrovascular complications. Glucose variability increased the risk of diabetic nephropathy and cerebrovascular complications.

CONCLUSIONS

Adiponectin and glypican-4 were associated with renal function and might be able to predict renal progression. Glucose variability was a predictable factor for diabetic nephropathy and cerebrovascular complications.

Long-term visit-to-visit glycemic variability as predictor of micro- and macrovascular complications in patients with type 2 diabetes: The Rio de Janeiro Type 2 Diabetes Cohort Study

BACKGROUND

Long-term visit-to-visit glycemic variability is an additional measure of glycemic control. We aimed to evaluate the prognostic value of several measures of glycemic variability for the occurrence of micro- and macrovascular complications, and all-cause mortality in patients with type 2 diabetes.

METHODS

654 individuals were followed-up over a median of 9.3 years. Glycemic variability (SDs and coefficients of variation of HbA1c and fasting glycaemia) was measured during the first 12- and 24-months. Multivariate Cox analysis, adjusted for risk factors and mean HbA1c and fasting glycaemia levels, examined the associations between glycemic variability and the occurrence of microvascular (retinopathy, microalbuminuria, renal function deterioration, peripheral neuropathy) and macrovascular complications [total cardiovascular events (CVE), major adverse CVEs (MACE) and cardiovascular mortality], and of all-cause mortality.

RESULTS

During follow-up, 128 patients had a CVE (96 MACE), and 158 patients died (67 from cardiovascular diseases); 152 newly-developed or worsened diabetic retinopathy, 183 achieved the renal composite outcome (89 newly developed microalbuminuria and 91 deteriorated renal function), and 96 newly-developed or worsened peripheral neuropathy. Glycemic variability, particularly the 24-month parameters either estimated by HbA1c or by fasting glycemia, predicted all endpoints, except for retinopathy and peripheral neuropathy development/progression, and was a better predictor than mean HbA1c. Glycemic variability predicted retinopathy development/progression in patients with good glycemic control (HbA1c ≤ 7.5%, 58 mmol/mol) and predicted new-incident peripheral neuropathy.

CONCLUSIONS

Long-term visit-to-visit glycemic variability is an additional and frequently a better glycemic parameter than mean HbA1c levels for assessing the risk of future development of micro- and macrovascular complications in patients with type 2 diabetes.

Characteristics of people with high visit-to-visit glycaemic variability in Type 2 diabetes

AIMS

Increased visit-to-visit glycaemic variability is independently associated with adverse outcomes in Type 2 diabetes. Our aim was to identify the patient characteristics associated with raised visit-to-visit glycaemic variability in people with Type 2 diabetes.

METHODS

A case-control study was conducted to establish associations between HbA_1c variability and clinical covariates in 10 130 people with Type 2 diabetes. Variability was calculated by two metrics [sd and coefficient of variation (CV)] from a minimum of four HbA_1c readings obtained over a 4-year period. High and low variability groups were defined as the top and bottom tertile of the sd or CV, and used in logistic regression analyses including a number of clinical and biochemical covariates. The analyses were stratified into low mean (< 53 mmol/mol; 7%) and high mean (≥ 53 mmol/mol; 7%) HbA_1c groups.

RESULTS

Findings were consistent across both HbA_1c groups and variability metrics. Treatment, independent of other factors, was the most strongly associated covariate for the risk of high HbA_1c variability. A six-fold increased risk was observed in the low HbA_1c group, between the most and least intense treatment regimens (P < 0.001). Similar findings were present in the high HbA_1c group with a three-fold increase in risk (P < 0.001). In addition, male gender, younger age, reduced HDL-cholesterol and increased BMI were all found to be independently associated with raised visit-to-visit glycaemic variability.

CONCLUSIONS

Intensive treatment resulting in low mean HbA_1c was associated with marked increase in HbA_1c variability. Irrespective of diabetes control, the greatest visit-to-visit variability was observed in young, insulin resistant men.

The impact of glycaemic variability on wound healing in the diabetic foot - A retrospective study of new ulcers presenting to a specialist multidisciplinary foot clinic

AIMS

Glycaemic variability - the visit-to-visit variation in HbA1c - plays a possible role in the development of micro and macrovascular disease in patients with diabetes. Whether HbA1c variability is a factor determining wound healing in diabetic foot ulcers remains unknown. We aimed to determine whether HbA1c variability is associated with foot ulcer healing time.

METHODS

A retrospective analysis of patients presenting to our specialist multidisciplinary foot clinic between July 2013 and March 2015, with at least three HbA1c measurements within five years of presentation and more than two follow-up reviews. HbA1c variation was measured by magnitude of standard deviation.

RESULTS

629 new referrals were seen between July 2013 and March 2015. Of these, 172 patients had their number of days to healing recorded and sufficient numbers of HbA1c values to determine variability. The overall geometric mean days to heal was 91.1 days (SD 80.8-102.7). In the low HbA1c variability group the geometric mean days to heal was 78.0 days (60.2-101.2) vs 126.9 days (102.0-158.0) in the high Hb1Ac variability group (p = .032). Those with low HbA1c (<58 mmol/mol) and low variability healed faster than those with high HbA1c and high variability (73.5 days [59.5-90.8] vs 111.0 days [92.0-134.0], p = .007). Additionally, our results show that time to healing is more dependent on the mean HbA1c than the variability in HbA1c (p = .007).

CONCLUSIONS/INTERPRETATION

Our data suggest that there was a significant association between HbA1c variability and healing time in diabetic foot ulcers.

Day-to-day fasting glycaemic variability in DEVOTE: associations with severe hypoglycaemia and cardiovascular outcomes (DEVOTE 2)

AIMS/HYPOTHESIS

The Trial Comparing Cardiovascular Safety of Insulin Degludec vs Insulin Glargine in Patients with Type 2 Diabetes at High Risk of Cardiovascular Events (DEVOTE) was a double-blind, randomised, event-driven, treat-to-target prospective trial comparing the cardiovascular safety of insulin degludec with that of insulin glargine U100 (100 units/ml) in patients with type 2 diabetes at high risk of cardiovascular events. This paper reports a secondary analysis investigating associations of day-to-day fasting glycaemic variability (pre-breakfast self-measured blood glucose [SMBG]) with severe hypoglycaemia and cardiovascular outcomes.

METHODS

In DEVOTE, patients with type 2 diabetes were randomised to receive insulin degludec or insulin glargine U100 once daily. The primary outcome was the first occurrence of an adjudicated major adverse cardiovascular event (MACE). Adjudicated severe hypoglycaemia was the pre-specified secondary outcome. In this article, day-to-day fasting glycaemic variability was based on the standard deviation of the pre-breakfast SMBG measurements. The variability measure was calculated as follows. Each month, only the three pre-breakfast SMBG measurements recorded before contact with the site were used to determine a day-to-day fasting glycaemic variability measure for each patient. For each patient, the variance of the three log-transformed pre-breakfast SMBG measurements each month was determined. The standard deviation was determined as the square root of the mean of these monthly variances and was defined as day-to-day fasting glycaemic variability. The associations between day-to-day fasting glycaemic variability and severe hypoglycaemia, MACE and all-cause mortality were analysed for the pooled trial population with Cox proportional hazards models. Several sensitivity analyses were conducted, including adjustments for baseline characteristics and most recent HbA_1c.

RESULTS

Day-to-day fasting glycaemic variability was significantly associated with severe hypoglycaemia (HR 4.11, 95% CI 3.15, 5.35), MACE (HR 1.36, 95% CI 1.12, 1.65) and all-cause mortality (HR 1.58, 95% CI 1.23, 2.03) before adjustments. The increased risks of severe hypoglycaemia, MACE and all-cause mortality translate into 2.7-, 1.2- and 1.4-fold risk, respectively, when a patient's day-to-day fasting glycaemic variability measure is doubled. The significant relationships of day-to-day fasting glycaemic variability with severe hypoglycaemia and all-cause mortality were maintained after adjustments. However, the significant association with MACE was not maintained following adjustment for baseline characteristics with either baseline HbA_1c (HR 1.19, 95% CI 0.96, 1.47) or the most recent HbA_1c measurement throughout the trial (HR 1.21, 95% CI 0.98, 1.49).

CONCLUSIONS/INTERPRETATION

Higher day-to-day fasting glycaemic variability is associated with increased risks of severe hypoglycaemia and all-cause mortality.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01959529.

Effectiveness of gliclazide MR 60 mg in the management of type 2 diabetes: analyses from the EASYDia trial

BACKGROUND

Although the number of antihyperglycemic agents has expanded significantly, sulfonylureas (in particular gliclazide) remain an important option because of a variety of patient and health system factors. The large, real world, observational, and international EASYDia trial evaluated the effectiveness of gliclazide modified release (MR) 60 mg in individuals with type 2 diabetes with a broad range of diabetes history, body mass index (BMI) and background antihyperglycemic treatment.

METHODS

A total of 7170 participants from eight countries, age ≥ 35 years with HbA1c ≥ 7.5% and not treated with insulin, were prescribed 30-120 mg of gliclazide MR 60 mg once daily. HbA1c goals were individualized and dosing uptitrated, as required, over the 6-month long study. In this post hoc subanalysis, efficacy endpoints were analyzed according to stratified baseline HbA1c levels, weight and glucose-lowering regimens. Episodes of hypoglycemia requiring assistance were documented.

RESULTS

At baseline, mean age was 58.9 years, HbA1c 8.8%, BMI 30.1 kg/m², and diabetes duration 5.1 years. At study end, clinically significant HbA1c improvements (mean change - 1.78%) were noted across all baseline HbA1c strata (> 7.0 to ≤ 8.0%, > 8.0 to ≤ 9.0%, > 9.0 to ≤ 10.0%, and > 10.0%), BMI classifications (18.5 to < 25.0, 25.0 to < 30.0, and ≥ 30.0 kg/m²), and regardless of the original diabetes treatment regimen (P < 0.001 in all cases). In contrast to the subgroups with BMI 25.0-30.0 and ≥ 30.0 kg/m² that registered weight losses of 0.9 and 2.2 kg, respectively (P < 0.001 vs. baseline weight); the BMI 18.5-24.9 kg/m² subgroup gained a mean 0.5 kg (P < 0.02 vs. baseline weight). Severe hypoglycemic events were rare (0.06%).

CONCLUSIONS

Progressive gliclazide MR 60 mg uptitration was well tolerated and lowered HbA1c across a broad range of HbA1c, BMI and background glucose-lowering therapy. Weight loss was noted when BMI was ≥ 25.0 kg/m². Individuals with the highest baseline HbA1c and BMI experienced the greatest HbA1c and weight improvements.Trial registration ISRCTN Registry ISRCTN00943368 on 1st July 2011.

Conflicting interactions of apolipoprotein A and high density lipoprotein cholesterol with microvascular complications of type 2 diabetes

AIMS

This study is amid at investigating the associations, and interactions of serum lipid biomarkers with microvascular complications of type 2 diabetes (T2D).

METHODS

A nested case-control study was conducted within an ongoing prospective study on patients with T2D. Microvascular complications of T2D including diabetic neuropathy, diabetic retinopathy and diabetic nephropathy were investigated. A total of 444 cases with at least one of the microvascular complications of T2D and 439 age- and gender-matched controls free of any of the chronic microvascular complications of T2D were included. The associations and interactions of a panel of serum lipid biomarkers with the microvascular complications of T2D were investigated.

RESULTS

Serum triglyceride had the strongest association with microvascular complications of T2D (crude model: β=0.632, P value=0.045). Each standard deviation increment in serum TG was associated with 3.7 times increased frequency of microvascular complications. Despite high density lipoprotein cholesterol (HDL-C), serum apolipoprotein A1 (Apo A1) was positively associated with the presence of diabetic neuropathy. Each standard deviation increment in serum ApoA1 was associated with increased frequency of diabetic neuropathy (OR, 1.2, 95% CI, (1.1-1.3), P value=0.006). The frequency of diabetic neuropathy was higher in 2nd and 3rd quartiles of serum Lp(a) compared to diabetic patients in the first quartile (OR, 5.52, 95% (1.17-25.8), P value=0.047).

CONCLUSIONS

ApoA1 but not HDL-C is straightly associated with diabetic neuropathy. Even Slight rise in serum Lp(a) is associated with increased frequency of diabetic retinopathLipid variables could serve as specific predictors of vascular complications in diabetes.

Variability in HbA1c, blood pressure, lipid parameters and serum uric acid, and risk of development of chronic kidney disease in type 2 diabetes

AIM

Variability in HbA1c and blood pressure is associated with the risk of diabetic kidney disease (DKD). No evidence exists on the role of variability in lipids or serum uric acid (UA), or the interplay between the variability of different parameters, in renal outcomes.

METHODS

Within the AMD Annals database, we identified patients with ≥5 measurements of HbA1c, systolic blood pressure (SBP) and diastolic blood pressure (DBP), total-, high-density lipoprotein (HDL)- and low-density lipoprotein (LDL)-cholesterol, triglycerides, and UA. Patients were followed-up for up to 5 years. The impact of measures of variability on the risk of DKD was investigated by Cox regression analysis and recursive partitioning techniques.

RESULTS

Four-thousand, two-hundred and thirty-one patients were evaluated for development of albuminuria, and 7560 for decreased estimated glomerular filtration rate (eGFR; <60 mL/min/1.73 m² ). A significantly higher risk of developing albuminuria was associated with variability in HbA1c [upper quartile hazard ratio (HR) = 1.3; 95% confidence interval (CI) 1.1-1.6]. Variability in SBP, DBP, HDL-C, LDL-C and UA predicted the decline in eGFR, the association with UA variability being particularly strong (upper quartile HR = 1.8; 95% CI 1.3-2.4). The concomitance of high variability in HbA1c and HDL-C conferred the highest risk of developing albuminuria (HR = 1.47; 95% CI 1.17-1.84), while a high variability in UA (HR = 1.54; 95% CI 1.19-1.99) or DBP (HR = 1.47; 95% CI 1.11-1.94) conferred the highest risk of decline in eGFR.

CONCLUSION

The variability of several parameters influences the development of DKD, having a different impact on albuminuria development and on the decline in GFR.

Impact of empagliflozin on subclinical left ventricular dysfunctions and on the mechanisms involved in myocardial disease progression in type 2 diabetes: rationale and design of the EMPA-HEART trial

Background

Asymptomatic left ventricular (LV) dysfunction is highly prevalent in type 2 diabetes patients. Unlike the other hypoglycemic drugs, SGLT2 inhibitors have shown potential benefits for reducing cardiovascular death and risk factors, aside from lowering plasma glucose levels. With this study we aim at determining whether the treatment with empagliflozin is associated with an improvement in LV functions in diabetic patients with asymptomatic LV dysfunction against Sitagliptin, which is presumably neutral on myocardial function. To determine changes in LV systolic and diastolic functions we will use speckle-tracking echocardiography, a novel sensitive, non-invasive, bedside method allowing the calculation of LV global longitudinal strain (GLS), an index of myocardial deformability, as well as 3D echocardiography, which allows a better evaluation of LV volumes and mass.

Methods

The EMPA-HEART trial will be a phase III, open label, active-controlled, parallel groups, single centre, exploratory study conducted in Pisa, Italy. A cohort of 75 diabetic patients with normal LV systolic (2D-Echo EF > 50%) and renal (eGFR sec MDRD > 60 ml/min/1.73 mq) functions and no evidence of valvular and/or ischemic heart disease will be randomized to either Empagliflozin 10 mg/die or Sitagliptin 100 mg/die. The primary outcome is to detect a change in GLS from baseline to 1 and 6 months after treatment initiation. The secondary outcomes include changes from baseline to 6 months in 3-D Echocardiography EF, left atrial volume and E/E′, VO₂max as measured at cardiopulmonary test, cardiac autonomic function tests (R–R interval during Valsalva manoeuvre, deep-breathing, lying-to-standing), and the determination of a set of plasma biomarkers aimed at studying volume, inflammation, oxidative stress, matrix remodelling, myocyte strain and injury.

Discussion

SGLT2 inhibitors might affect myocardial functions through mechanisms acting both directly and indirectly on the myocardium. The set of instrumental and biohumoral tests of our study might actually detect the presence and entity of empagliflozin beneficial effects on the myocardium and shed light on the mechanisms involved. Further, this study might eventually provide information to design a clinical strategy, based on echocardiography and/or biomarkers, to select the patients who might benefit more from this intervention.

Trial registration EUDRACT Code 2016-0022250-10

Trajectories of fasting plasma glucose variability and mortality in type 2 diabetes

AIM

To investigate the effect of changes in fasting plasma glucose (FPG) variability, as assessed by 2-year trajectories of FPG variability, on mortality risk in patients with type 2 diabetes (T2D).

METHODS

From 2009 to 2012, outpatients with T2D, aged>18 years, were enrolled from a medical centre. FPG was measured every 3 months for 2 years in 3569 people. For each of the eight 3-month intervals, FPG variability and means were calculated, with variability defined as the coefficient of variation of FPG. Also, trajectories of FPG variability and means were determined separately, using group-based trajectory analysis with latent class growth models. These models were fitted using the SAS Proc Traj procedure. The primary outcome was all-cause mortality, which was followed-up to the end of 2014.

RESULTS

Five distinct trajectories of FPG variability (low, increasing, fluctuating, decreasing and high) and means (well controlled, stable control, worsening control, improving control and poor control) were established. The five trajectories of mean FPG were all associated with the same mortality risk. In contrast, in comparison to the low FPG variability trajectory, the fluctuating, decreasing and high variability trajectories all had significantly higher risks of mortality, with respective hazards ratios of 2.63 (95% CI: 1.40-4.93; P=0.003), 2.78 (95% CI: 1.33-5.80; P=0.007) and 4.44 (95% CI: 1.78-11.06; P=0.001) after multivariable adjustment.

CONCLUSION

Changes in FPG variability were independently associated with increased mortality risk in patients with T2D.

Comparison of the relationship between multiple parameters of glycemic variability and coronary plaque vulnerability assessed by virtual histology-intravascular ultrasound

AIMS/INTRODUCTION

Increased glycemic variability is an important contributing factor to coronary artery disease. Although various parameters of glycemic variability can be derived by continuous glucose monitoring, the clinical relevance of individual parameters has remained unclear. We have now analyzed the relationship of such parameters to coronary plaque vulnerability.

MATERIALS AND METHODS

The standard deviation of glucose levels (SD glucose), mean amplitude of glycemic excursions (MAGE), continuous overlapping net glycemic action calculated every 1 h (CONGA-1) and mean of daily differences (MODD) were calculated from continuous glucose monitoring data for 53 patients hospitalized for percutaneous coronary intervention. The relationship of these parameters to the percentage necrotic core of total plaque volume (%NC) as assessed by virtual histology-intravascular ultrasound (a predictor of coronary plaque rupture) was evaluated.

RESULTS

All parameters of glycemic variability were significantly correlated with %NC, with correlation coefficients of 0.593, 0.626, 0.318, and 0.388 for log(SD glucose), log(MAGE), CONGA-1 and log(MODD), respectively. Simple linear regression analysis showed that the coefficients of determination for %NC and either log(SD glucose; 0.352) or log(MAGE; 0.392) were greater than those for %NC and either CONGA-1 (0.101) or log(MODD; 0.151), whereas the residual sums of squares for the former relationships (1045.1 and 979.5, respectively) were smaller than those for the latter (1449.3 and 1369.6, respectively).

CONCLUSIONS

The present data suggest that SD glucose and MAGE are more highly correlated with coronary plaque vulnerability than are CONGA-1 and MODD, and are thus likely better predictors of coronary artery disease.

The Durability of Basal Insulin Affects Day-to-Day Glycemic Variability Assessed by Continuous Glucose Monitoring in Type 2 Diabetes Patients: A Randomized Crossover Trial

BACKGROUND

Not only within-day glycemic variability but also day-to-day glycemic variability is a risk factor for diabetic patients. However, the ways of controlling day-to-day glycemic variability are unclear. We hypothesized that the durability of basal insulin plays an important role in controlling day-to-day glycemic variability in type 2 diabetes patients, and we therefore aimed to evaluate whether glargine U300, which exhibits prolonged absorption compared with glargine U100 but the same composition as glargine U100, would lead to improved day-to-day glycemic variability.

MATERIALS AND METHODS

This was a single-center, randomized, open-label, crossover study in type 2 diabetes patients using basal insulin therapy. After switching from 4 weeks of treatment with glargine U100 or U300, the patients performed continuous glucose monitoring (CGM) for 72 h in an environment with routine activities and mealtimes. The mean of daily difference (MODD) was assessed as day-to-day glycemic variability.

RESULTS

We enrolled 22 patients, and 17 patients completed the study. The MODD assessed as day-to-day glycemic variability was significantly lower with glargine U300 than with glargine U100 (1.8 ± 0.6 mmol/L vs. 2.4 ± 0.9 mmol/L, P = 0.006). No significant difference was observed in short-term glycemic variability between the two glargine formulations as measured by the standard deviation, coefficient of variation, mean amplitude of glucose excursion.

CONCLUSIONS

Compared with glargine U100 treatment, glargine U300 treatment improved the MODD as assessed by CGM in type 2 diabetes patients. These findings suggest that the durability of basal insulin may be associated with day-to-day glycemic variability in type 2 diabetes patients.

The efficacy and safety of adding either vildagliptin or glimepiride to ongoing metformin therapy in patients with type 2 diabetes mellitus

OBJECTIVE

To compare the effects of either vildagliptin or glimepiride on glycemic variability, oxidative stress, and endothelial parameters in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin alone.

METHODS

In this randomized, open-label, parallel study, 34 patients with T2DM being treated with metformin having an HbA1c of 7.0-10.0% were allocated into either the vildagliptin or glimepiride group. A mixed-meal tolerance test and 72-hour continuous glucose monitoring were conducted, and urinary 8-iso-prostaglandinF_2α (PGF_2α) and endothelial-dependent flow-mediated dilatation (FMD) were evaluated at baseline and after 12 weeks of treatment.

RESULTS

Similar significant improvements in HbA1c level were shown in both vildagliptin (-0.8%) and glimepiride (-0.9%) groups after treatment (Ps<0.001). The mean amplitude of glycemic excursions (MAGE) and the mean of daily differences (MODD) were significantly decreased by vildagliptin (P = 0.044 and P = 0.031, respectively) but not by glimepiride. Glimepiride was significantly associated with a higher incidence of hypoglycemia than vildagliptin (P = 0.005). There were no significant differences in urinary 8-iso-PGF_2α or FMD between the two groups.

CONCLUSIONS

Vildagliptin effectively improved glucose level with a significantly greater reduction in glycemic variability and hypoglycemia than glimepiride in patients with T2DM ongoing metformin therapy. The two drugs showed no significant differences in urinary 8-iso-PGF_2α and FMD.

TRIAL REGISTRATION

NCT01404676.

The relationship between fasting blood glucose variability and coronary artery collateral formation in type 2 diabetes patients with coronary artery disease

BACKGROUND

Coronary collaterals are an alternative source of blood supply to ischemic myocardium. Well-developed coronary collateral arteries in patients with coronary artery disease (CAD) limit the size of acute myocardial infarction and improves survival. The aim of this study was to investigate the relationship between glycemic variability and coronary collateral formation in patients with type 2 diabetes mellitus and CAD.

METHODS

Consecutive patients undergoing percutaneous coronary intervention or coronary artery bypass grafting procedures were studied. Multivariate logistic regression models were used to examine the association between coronary artery collateral formation graded by Rentrope classification and glycemic variability, measured by coefficient variation of fasting blood glucose.

RESULTS

In our study, we retrospectively enrolled 300 patients, of whom 239 were diabetic (age: 70.1±11.9, 56% men) and 61 were nondiabetic (age: 71.5±11.5, 72% men). Diabetic patients were further stratified as follows: those with poor coronary collateral artery development (n=171, age: 69.7±12.4, 55% men) and those with good coronary collateral artery development (n=68, age 71.1±10.8, 59% men) according to the Rentrope classification. Our findings did not show association between glycemic variability and coronary collateral vessels development after controlling for potential confounders (odds ratio: 2.51; 95% confidence interval: 0.57-11.03; P=0.22). The culprit lesion (≥75% stenosis) in the left anterior descending artery and the right coronary artery was more frequent in the good collateral group compared with the poor collateral group (66 vs. 50%, P=0.02; 63 vs. 45%, P=0.01 respectively).

CONCLUSION

Glycemic variability is not associated with coronary collateral artery formation in patients with type 2 diabetes mellitus and CAD.

[Why is a combination of basal insulin with a GLP-1 receptor agonist useful in many patients with type 2 diabetes?]

BACKGROUND

In 2015, the combination of basal insulin and GLP-1 receptor agonist (RA) was incorporated into the guideline recommendations for type 2 diabetes as an option for the last escalation step. The two antidiabetics to be injected subcutaneously are complementary regarding their respective main effects and limitations. Basal insulin is predominantly active between meals and in the fasting state, whereas the main action of GLP-1 RA consists in preventing an excessive postprandial blood glucose increase. Moreover, GLP-1 RA is characterised by a low intrinsic risk of hypoglycaemia, body weight reduction and a positive impact on cardiovascular risk factors. Unlike GLP-1 RA, no upper dose limits are defined for basal insulin. However, initiation of insulin therapy is associated with disadvantages in terms of hypoglycaemia and weight increase. Therefore, patients achieving their treatment goals with GLP-1 RA alone are better treated without insulin.

METHOD

In a review, study results on combinations of basal insulin and GLP-1-RA versus comparative therapies are presented.

RESULTS

Most of the studies were carried out in patients pre-treated with basal insulin. The add-on of GLP-1 RA was commonly associated with significant reductions of body weight and also resulted in additional HbA_1c reductions compared with an increase of the basal insulin dose. The add-on of a short acting insulin to an existing basal insulin therapy enabled similar HbA_1c reductions to the add-on of a GLP-1 RA, but simultaneously increased the number of episodes of hypoglycaemia and might lead to more unfavourable body weight developments. A fixed combination of insulin degludec and liraglutide (IDegLira) showed an effective and rather steady blood glucose reduction in a 24-hour interval vs. basal insulin or GLP-1 RA alone.

CONCLUSIONS

Combinations of basal insulin and a GLP-1 RA improve glycaemic control in many patients with type 2 diabetes without any significant increase of the risk of hypoglycaemia and without weight gain, especially compared to a dose increase of the basal insulin or add-on of a short-acting insulin.

Impact of Visit-to-Visit Variability in Systolic Blood Pressure on Cardiovascular Outcomes in Korean National Health Insurance Service-National Sample Cohort

BACKGROUND

Despite an association between visit-to-visit blood pressure (BP) variability (VV-BPV) and cardiovascular (CV) outcomes, many studies performed during the past 4 years have shown conflicting results. This study investigated the impact of VV-BPV on CV outcomes in the Korean National Health Insurance Service (NHIS) database-National Sample Cohort.

METHODS

From the 2002 Korean NHIS database (n = 47,851,928), sample subjects with 3 or more BP measurements (n = 51,811) were divided into 2 groups according to a 10 mm Hg cutoff in the SD of systolic BP (SD-SBP). The CV outcomes of these groups were compared by sensitivity analyses using various sampling methods.

RESULTS

Irrespective of sampling method, subjects with SD-SBPs ≥10 mm Hg had higher rates of CV events or death, nonfatal myocardial infarction (MI) or stroke, and total mortality, but were not associated with CV mortality. The hazard ratios for CV events or death, nonfatal MI or stroke, CV mortality, and total mortality were 1.43 (95% confidence interval [CI], 1.25-1.63, P < 0.01), 1.45 (95% CI, 1.27-1.65, P < 0.01), 1.32 (95% CI, 0.89-1.94, P = 0.17), and 1.18 (95% CI, 1.01-1.38, P = 0.04), respectively.

CONCLUSIONS

Increased VV-BPV was an independent risk factor for future CV outcomes, independent of mean BP status, even in normotensive subjects and in all subgroups, except females. Similar VV-BPV values in the sensitivity analyses suggest VV-BPV is a reproducible phenomenon, reflecting the various types of intrinsic physiologic properties.

Variability in glycated albumin levels predicts the progression of diabetic nephropathy

AIM

The present study was performed to assess variability in glycated albumin (GA) using a coefficient of variation (CV) to predict the progression of diabetic nephropathy in type 2 diabetic patients, independently of HbA1c and other conventional risk factors.

METHODS

The present study consecutively enrolled 369 patients with type 2 diabetes mellitus from outpatient clinic. During the follow-up period, GA and HbA1c levels were measured repeatedly (≥5 times), and the CV of GA (GA-CV) was calculated for each patient. The patients were divided into two subgroups: Group 1, a MEAN-HbA1c value <7.2% (55mmol/mol); Group 2, a MEAN-HbA1c value ≥7.2% (55mmol/mol). The primary outcome was the renal composite outcome (RCO), which was based on the progression rates of chronic kidney disease and albuminuria and renal death.

RESULTS

The median follow-up period was 33months. The RCO was developed in 109 patients (29.5%). In Group 1, the third highest and highest quartile groups for GA-CV had higher cumulative incidences of the RCO than those of the lowest quartile group (Q4 vs. Q1: HR=5.43, P=0.007, Q3 vs. Q1: HR=5.16, P=0.009). After adjusting for HbA1c levels and other risk factors, the GA-CV remained significantly associated with the development of the RCO. However, Group 2 did not exhibit any significant differences in terms of the cumulative incidence of the RCO among the four GA-CV quartile groups.

CONCLUSIONS

The present findings suggest that variability in GA may be a better predictor of the progression of diabetic nephropathy in type 2 diabetic patients regardless of HbA1c.

Predictive ability of visit-to-visit variability in HbA1c and systolic blood pressure for the development of microalbuminuria and retinopathy in people with type 2 diabetes

AIMS

We explored whether visit-to-visit variability in both glycated hemoglobin (HbA1c) and systolic blood pressure (SBP) simultaneously predicted the development of microalbuminuria and retinopathy, and whether the predictive ability of these measurements changed according to mean HbA1c and SBP levels in people with type 2 diabetes.

METHODS

A retrospective observational cohort study was conducted on 243 type 2 diabetes patients with normoalbuminuria and 486 without retinopathy at the first visit and within 1year thereafter. The two cohorts were followed up from 1995 until 2012. Multivariate and stratified analyses were performed using Cox proportional hazard models.

RESULTS

Microalbuminuria developed in 84 patients and retinopathy in 108. Hazard ratios (HRs) for the development of microalbuminuria associated with the coefficient of variation (CV) and variation independent of mean (VIM) of both HbA1c and SBP significantly increased. In participants with a mean SBP <130mmHg, the HRs for the development of retinopathy associated with CV and VIM of HbA1c were abruptly elevated and significant compared with those with a mean SBP ≥130mmHg.

CONCLUSIONS

Visit-to-visit variability in both HbA1c and SBP simultaneously predict the development of microalbuminuria. HbA1c variability may predict the development of retinopathy when the mean SBP is normal (<130mmHg).

Influenza Virus and Glycemic Variability in Diabetes: A Killer Combination?

Following the 2009 H1N1 influenza virus pandemic, numerous studies identified the striking link between diabetes mellitus and influenza disease severity. Typically, influenza virus is a self-limiting infection but in individuals who have a pre-existing chronic illness, such as diabetes mellitus, severe influenza can develop. Here, we discuss the latest clinical and experimental evidence for the role of diabetes in predisposing the host to severe influenza. We explore the possible mechanisms that underlie this synergy and highlight the, as yet, unexplored role that blood glucose oscillations may play in disease development. Diabetes is one of the world’s fastest growing chronic diseases and influenza virus represents a constant and pervasive threat to human health. It is therefore imperative that we understand how diabetes increases influenza severity in order to mitigate the burden of future influenza epidemics and pandemics.

Increased risk for diabetes development in subjects with large variation in total cholesterol levels in 2,827,950 Koreans: A nationwide population-based study

BACKGROUND

Recent studies suggest a role for hyperlipidemia in the development of diabetes. The aim of this study is to analyze the relationship between variations of total cholesterol (TC) levels and the risk for type 2 diabetes development from a Korean nationwide population-based database.

MATERIALS AND METHODS

We examined the General Health Check-up sub-dataset of the Korean National Health Insurance Service (NHIS) of 2,827,950 participants who had at least three health check-ups between 2002 and 2007, and were not reported to have diabetes during that time. The variations of TC levels between the examinations were calculated as follows: [Formula: see text]. The examinees were divided into 10 groups according to TC variation, and the hazard ratio for diabetes development from 2007 to 2013, were analyzed.

RESULTS

During the follow-up period, 3.4% of the participants had developed diabetes. The hazard ratio (HR) for diabetes development relative to the overall risk in the whole study population started to be higher than 1.0 from eighth decile of TC variation. The highest decile group showed an increased HR for diabetes development after adjustment for confounding variables (1.139; 95% confidence interval 1.116~1.163). These results were similar regardless of the use of anti-hyperlipidemic medication and baseline TC levels.

CONCLUSIONS

The participants with a large variation in TC levels showed an increased risk for diabetes development, independent of the use of anti-hyperlipidemic medications. These results suggest a relationship between fluctuations in lipid levels and the development of type 2 diabetes.

Predictive and explanatory factors of cardiovascular disease in people with adequately controlled type 2 diabetes

Aims To explore the predictive and explanatory factors on the incidence of cardiovascular disease and the impact of visit-to-visit variability (VVV) of risk factors on incident cardiovascular disease in people with type 2 diabetes with no history of prior cardiovascular disease. Methods We performed a historical cohort study (2008-2011) on 481 people with type 2 diabetes and no history of cardiovascular disease. Cardiovascular risk factors were assessed at baseline and repeatedly during follow-up. The predictive analysis included the variables at enrollment, and explanatory analyses were based on mean of the variables measured repeatedly. VVV of the main variables was measured using the standard deviation and coefficient of variation of the measured variables. Separate multivariate binary logistic models were constructed for each parameter with the incident cardiovascular disease. Results Mean age of the participants was 54.9 years, mean glycated hemoglobin was 56 mmol/mol, and mean blood pressure was 125/78 mmHg. Incident cardiovascular disease developed in 14.3% of the participants. The 2-h post breakfast blood glucose was associated with incident cardiovascular disease (odds ratio 1.44; confidence interval = 1.08-1.90; p = 0.01). For each 1 mmol/l increase in postprandial glucose there was a 44% increase in risk of incident cardiovascular disease. VVV of glycemic indices, blood pressure, lipids, body mass index and creatinine were not associated with occurrence of cardiovascular events. Conclusion In this population of patients with type 2 diabetes and no history of cardiovascular disease in whom other cardiovascular risk factors are within or near to the recommended targets, 2-h post breakfast blood glucose level is associated with incident cardiovascular disease.

Comparison of morning basal + 1 bolus insulin therapy (insulin glulisine + insulin glargine 300 U/mL vs insulin lispro + insulin glargine biosimilar) using continuous glucose monitoring: A randomized crossover study

INTRODUCTION

We compared the effects of morning administration of insulin glulisine + insulin glargine 300 U/mL (G + G300) with that of insulin lispro + insulin glargine biosimilar (L + GB).

MATERIALS AND METHODS

A total of 30 patients with type 2 diabetes who wore a continuous glucose monitoring device on admission after glucose levels were stabilized by morning long-acting and ultra-rapid-acting insulins were randomly allocated to groups who received G + G300 on days 1 and 2, and the same dose L + GB on days 3 and 4, or vice versa. Data collected on days 2 and 4 (mean amplitude of glycemic excursion, mean of daily differences: all days) were analyzed. Insulin was injected at 08.00 h. A day was defined as the period from 08.00 h one day, to 08.00 h the next day. Test meals were given.

RESULTS

Increased post-breakfast glucose level, post-breakfast glucose gradient, mean glucose level, standard deviation and M-value (24 h, 00.00-06.00 h), mean amplitude of glycemic excursion, and mean of daily differences were significantly lower in patients taking G + G300 than those taking L + GB (P ≤ 0.0001-0.04). The area over the glucose curve (<70 mg/dL) was not significantly different between groups. Pre-lunch - pre-breakfast glucose levels were significantly lower in patients taking L + GB than those taking G + G300 (P < 0.0001). The difference in the highest post-breakfast glucose level between groups (Δ = G + G300 - L + GB) was significantly correlated to 24-h mean glucose level (r = 0.40, P = 0.03).

CONCLUSIONS

Compared with L + GB, G + G300 decreases post-breakfast glucose level reducing rate of rise of that, nocturnal and 24-h glucose variability and level without causing hypoglycemia, and daily variance.

Associations between body fat variability and later onset of cardiovascular disease risk factors

OBJECTIVE

There is current debate regarding whether body weight variability is associated with cardiovascular events. Recently, high body fat percentage (BF%) has been shown to be a cardiovascular risk factor. We therefore hypothesized that BF% variability would present a stronger cardiovascular risk than body weight variability.

METHODS

A single-center retrospective cohort study of medical check-up examinees aged 20 years or older at baseline (2005) was performed. Examinees were followed in 2007, 2009, and 2013-2014. BF% variability in 2005, 2007 and 2009 was calculated as the root-mean square error (RMSE) using a simple linear regression model. Multiple logistic regression models estimated the association between BF%-RMSE and new diagnoses of cardiovascular risk factors occurring between the 2009 and 2013-2014 visits.

RESULTS

In total, 11,281 participants (mean age: 51.3 years old, 48.8% were male) were included in this study. The average BF%-RMSE of our subjects was 0.63, and the average BMI-RMSE was 0.24. The high BF%-RMSE group (76-100th percentile) had a higher incidence of hypertension and a lower incidence of diabetes mellitus than the low BF%-RMSE group (1-25th percentile). This tendency was particularly evident in male participants. BMI-RMSE was not associated with any cardiovascular risks in our study.

CONCLUSIONS

This study indicates that body fat variability has contrasting effects on cardiovascular risk factors, while body weight variability has no significant effects.

Visit-to-Visit Low-Density Lipoprotein Cholesterol Variability Is an Independent Determinant of Carotid Intima-Media Thickness in Patients With Type 2 Diabetes

Background

Studies demonstrated that visit-to-visit variability in low-density lipoprotein cholesterol (LDLC) is an independent predictor of cardiovascular events in subjects with coronary artery disease. Whether visit-to-visit variability in LDLC levels affects subclinical atherosclerosis is unknown. This study sought to evaluate the role of visit-to-visit variability in LDLC levels on subclinical atherosclerosis.

Methods

We evaluated 162 type 2 diabetic patients with measurement of carotid intima-media thickness (IMT). Intrapersonal mean and standard deviation (SD) of six measurements of LDLC during 12 months were calculated. Multivariate linear regressions assessed the independent correlates of carotid IMT.

Results

The mean and SD of LDLC were 112 ± 22 and 15 ± 10 mg/dL, respectively, and 43.2% of patients were on hypolipidemic drugs. Age (standardized β = 0.355, P < 0.001), male sex (standardized β = 0.234, P = 0.002) and SD-LDLC (standardized β = 0.201, P = 0.009) emerged as independent determinants of carotid maximum IMT independently of mean LDLC levels, body mass index (BMI), waist circumference, duration and treatment of diabetes, means and SDs of glycemic and other lipid variables, and uses of hypolipidemic and anti-hypertensive medications (R² = 0.15). Results did not change when mean IMT was used instead of maximum IMT. After controlling for age and sex, maximum IMT was thicker in patients with the highest compared to those with other three quartiles of SD-LDLC combined (1.14 ± 0.04 (SE) vs. 1.01 ± 0.02 mm, P = 0.01). Independent determinants of SD-LDLC were mean LDLC, use of hypolipidemic drugs, fasting triglyceride and visit-to-visit variability in HbA1c.

Conclusions

Consistency of LDLC levels may be important to subclinical atherosclerosis in real-world patients with type 2 diabetes. It may be important for patients on lipid-lowering drugs to prevent non-compliance.

Postmeal triglyceridemia and variability of HbA1c and postmeal glycemia were predictors of annual decline in estimated glomerular filtration rate in type 2 diabetic patients with different stages of nephropathy

BACKGROUND

This study examined associations of annual glycemic variability and postprandial dysmetabolism with annual decline in estimated glomerular filtration rate (eGFR) in type 2 diabetic patients with different stages of nephropathy.

METHODS

Intrapersonal mean and coefficient of variation (CV) of HbA1c, fasting and postmeal concentrations of plasma glucose (FPG and PMPG, respectively) and serum triglycerides (FTG and PMTG, respectively) during the first 12 months after enrollment were calculated in a cohort of 168 type 2 diabetic patients: 53 with optimal albumin/creatinine ratio (ACR < 10 mg/g), 62 with high normal ACR (10-29 mg/g) and 53 with elevated ACR (≧30 mg/g). Annual changes in eGFR were computed using 52 (median) creatinine measurements obtained over a median follow-up of 6.0 years. Multivariate linear regressions assessed the independent correlates of changes in eGFR.

RESULTS

Kidney function declined faster in patients with high normal and elevated ACR (-1.47 and -2.01 ml/min/1.73 m2/year, respectively) compared to patients with optimal ACR (0.08 ml/min/1.73 m2/year, p < 0.05). In patients with high normal ACR, age (standardized β、-0.30、p = 0.01), CV-HbA1c (standardized β、-0.66、p < 0.001) and CV-PMPG (standardized β、-0.27、p = 0.01) was associated with annual eGFR decline independently of mean HbA1c and PMPG, sex, BMI, waist circumference, diabetes duration and therapy, means and CVs of FPG and systolic blood pressure, baseline eGFR, log ACR and uses of anti-hypertensive medications (R2 = 0.47). In patients with elevated ACR, PMTG (standardized β、-0.408, p = 0.007) was associated with annual eGFR decline (R2 = 0.15).

CONCLUSIONS

Consistency of glycemic control and management of postprandial glycemia and lipidemia are important to preserve kidney function in type 2 diabetic patients.

Ten-year hemoglobin A1c trajectories and outcomes in type 2 diabetes mellitus: The Diabetes & Aging Study

AIMS

To classify trajectories of long term HbA1c values in patients after diagnosis of type 2 diabetes and examine each trajectory's associations with subsequent microvascular and macrovascular events and mortality.

METHODS

A longitudinal follow-up of 28,016 patients newly diagnosed with type 2 diabetes was conducted. Latent growth mixture modeling was used to identify ten-year HbA1c trajectories. Cox proportional hazards models were used to assess how HbA1c trajectories were associated with events (microvascular and macrovascular) and mortality.

RESULTS

We identified 5 HbA1c trajectories: "low stable" (82.5%), "moderate increasing late" (5.1%), "high decreasing early" (4.9%), "moderate peaking late" (4.1%) and "moderate peaking early" (3.3%). After adjusting for average HbA1c, compared to the low stable trajectory, all non-stable trajectories were associated with higher incidences of microvascular events (hazard ratio (HR) range, 1.28 (95% CI, 1.08-1.53) (high decreasing early) to 1.45 (95% CI, 1.20-1.75) (moderate peaking early)). The high decreasing early trajectory was associated with an increased mortality risk (HR, 1.27 (95% CI, 1.03-1.58)). Trajectories were not associated with macrovascular events.

CONCLUSIONS

Non-stable HbA1c trajectories were associated with greater risk of microvascular events and mortality. These findings suggest a potential benefit of early diabetes detection, prioritizing good glycemic control, and maintaining control over time.

Fasting plasma glucose variability and all-cause mortality among type 2 diabetes patients: a dynamic cohort study in Shanghai, China

The study aims to examine whether the variation of fasting plasma glucose (FPG), represented by coefficient of variation (CV), independently predicts all-cause mortality among Chinese type 2 diabetes patients. This retrospective cohort study was designed based on a standardized electronic management system of diabetes patients in Shanghai, China. 8871 type 2 diabetes patients were enrolled between 1 January 2007 and 31 December 2007 and were followed-up for all-cause mortality until 31 December 2014. All patients were grouped by the quartiles of CV of FPG. 1136 patients deceased during following-up. After adjusting for other risk factors, CV of FPG was not independently associated with all-cause mortality. Stratified analysis by mean FPG levels (<7 mmol/L and ≥7 mmol/L) observed a significant modifying effect of CV of FPG (P for interact test <0.01). CV of FPG was independently associated with all-cause mortality in patients whose glucose control was poor, with the HRs (95% CI) for the second, third, fourth vs first quartiles of CV of FPG being 1.23(0.94–1.61), 1.23(0.94–1.61), and 1.63(1.25–2.13), respectively. Our results suggest that variability of FPG may be an important predictor of mortality among type 2 diabetes in China, particularly for those with their glycemic status uncontrolled.

Clinical Course and Risk Factors of Diabetic Retinopathy in Patients with Type 2 Diabetes Mellitus in Korea

BACKGROUND

We investigated clinical course and risk factors for diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 759 patients with T2DM without DR were included from January 2001 to December 2004. Retinopathy evaluation was performed at least annually by ophthalmologists. The severity of the DR was classified into five categories according to the International Clinical Diabetic Retinopathy Severity Scales.

RESULTS

Of the 759 patients, 523 patients (68.9%) completed the follow-up evaluation. During the follow-up period, 235 patients (44.9%) developed DR, and 32 patients (13.6%) progressed to severe nonproliferative DR (NPDR) or proliferative DR (PDR). The mean duration of diabetes at the first diagnosis of mild NPDR, moderate NPDR, and severe NPDR or PDR were 14.8, 16.7, and 17.3 years, respectively. After adjusting multiple confounding factors, the significant risk factors for the incidence of DR risk in patients with T2DM were old age, longer duration of diabetes, higher mean glycosylated hemoglobin (HbA1c), and albuminuria. Even in the patients who had been diagnosed with diabetes for longer than 10 years at baseline, a decrease in HbA1c led to a significant reduction in the risk of developing DR (hazard ratio, 0.73 per 1% HbA1c decrement; 95% confidence interval, 0.58 to 0.91; P=0.005).

CONCLUSION

This prospective cohort study demonstrates that glycemic control, diabetes duration, age, and albuminuria are important risk factors for the development of DR. More aggressive retinal screening for T2DM patients diagnosed with DR should be required in order to not miss rapid progression of DR.

Inter-regulation of gastric emptying and incretin hormone secretion: implications for postprandial glycemic control

The GI tract is central to the regulation of postprandial glycemia, with the rate of gastric emptying and the secretion of the incretin hormones, glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1, being key determinants. Gastric emptying exhibits a large interindividual variation; the latter not only accounts for differences in postprandial glycemia but also determines postprandial incretin profiles. Accordingly, the rate of gastric emptying may affect the glucose-lowering efficacy of dipeptidyl peptidase-4 inhibitors. In contrast, glucagon-like peptide-1 receptor agonists lower postprandial glycemia predominantly by their action to slow gastric emptying. This review discusses the inter-relationship between gastric emptying and the incretin axis in the context of changes in blood glucose, with an emphasis on the relevant clinical implications.

Association of variability in hemoglobin A1c with cardiovascular diseases and mortality in Chinese patients with type 2 diabetes mellitus - A retrospective population-based cohort study

AIMS

This study aimed to investigate the association between variability in HbA1c and incidence of cardiovascular disease (CVD) event and mortality among Chinese primary care patients with Type 2 diabetes mellitus (T2DM).

METHODS

A retrospective cohort study was conducted on 91,866 T2DM patients aged ≥18years without any history of CVD. Variability in HbA1c, was measured by standard deviation (SD), associated with the risks of CVD and all-cause mortality were evaluated using Cox proportional hazards regression analysis by age groups ( 65 and ≥ 65 years old)." to "Variability in HbA1c was measured by standard deviation (SD) The association between Variability in HbA1c and the incidence of CVD and all-cause mortality were evaluated using Cox proportional hazards regression analysis by age groups ( 65 and ≥ 65 years old).

RESULTS

Over a median follow-up of 58.5months, our study identified a positive linear relationship between variability in HbA1c and incidence of CVD and all-cause mortality in the younger and older groups. For every 1-SD increase in HbA1c, the risk of CVD events in the older group only increased by 15.2% (95% CI: 1.026-1.293), and the risks of all-cause mortality in both age groups increased by 49.5% (95% CI: 1.154-1.936) and 77.8% (95% CI: 1.563-2.024), respectively.

CONCLUSIONS

The HbA1c variability independently of the mean HbA1c level may provide additional valuable information as a potential predictor for the development of CVD and all-cause mortality in diabetic patients, particularly for the elderly patients.

Glucose Control and Vascular Outcomes in Type 2 Diabetes: Is the Picture Clear?

The overall impact of glucose lowering on vascular complications and major clinical outcomes, including mortality, in type 2 diabetes is still an open issue. While intensive glucose control has undoubted benefit for microvascular end points, the relationship between glucose-lowering approaches and reduced incidence and/or progression of macrovascular complications is less clear. This review article will discuss the effect of glucose lowering per se as well as the effects of specific glucose-lowering therapies on vascular outcomes in type 2 diabetes. The role of lifestyle changes on cardiovascular outcomes will be also addressed. Recent analyses from large cardiovascular outcome studies (ACCORD, ADVANCE, and VADT) provide new information on factors that modulate the impact of intensive glucose lowering on outcomes, helping to identify the specific clinical characteristics of the patients receiving the intervention that would show a better response. While several studies on cardiovascular outcomes with diabetes drugs are available, they do not clearly highlight a benefit from using a specific medication or will require additional evidence, as for the sodium-glucose cotransporter 2 blockers.

Emotional reactivity to daily stress, spousal emotional support, and fasting blood glucose among patients with type 2 diabetes

Stress is associated with higher blood glucose in patients with diabetes, but the strength of this association varies considerably across patients. The current daily diary study of 129 patients with type 2 diabetes examined whether individual differences in emotional stress reactivity were associated with fasting blood glucose and whether emotional support provided by spouses moderated this association. Greater stress reactivity was related to greater variability in patients’ fasting glucose readings and, among patients with less support, to higher fasting glucose levels. Investigating individual differences in emotional stress reactivity may help to clarify the role of stress in blood glucose control.