Glycemic variability and diabetes retinopathy: a missing link

Identification of Risk Factors for the Development of Diabetic Retinopathy Among Palestinian Adults With Type 2 Diabetes Mellitus: A Cross-Sectional Study

INTRODUCTION

Although risk factors linked to diabetic retinopathy (DR) among patients with Type 2 diabetes mellitus (T2DM) have been extensively studied globally, the specific determinants of these factors in relation to DR in Palestine are presently not well understood.

METHODS

This retrospective cross-sectional study included patients who underwent DR screening with a fundus camera (VersaCam a). The study included patients aged ≥18 with T2DM, excluding those with other types of diabetes or a history of malignancies. Univariable and multivariable logistic regressions were used to identify factors associated with DR.

RESULTS

A total of 1163 patients with T2DM were included in this study. Of these, 211 (18.1%) patients were classified in the DR group, 761 (65.4%) in the no DR group and 191 (16.4%) were ungradable. Among the included patients, 434 (37.3%) were male. A secondary level of education or higher and a BMI ≥30 kg/m2, compared with <25 kg/m2, were independently and inversely associated with DR, with odds ratios (ORs) of 0.46 (p < 0.001) and 0.58 (p = 0.046), respectively. A 5-year increase in the duration of T2DM correlated with 45% higher odds of having DR (p < 0.001). Patients with DR were more likely to have HbA1c >7%, be physically inactive and use insulin, with ORs of 1.63 (p = 0.02), 2.05 (p < 0.001) and 1.53 (p = 0.03), respectively. Age, gender, occupational status, hypertension and hyperlipidaemia were not independent predictors of DR (p < 0.05).

CONCLUSION

Longer duration of T2DM, HbA1c >7%, physical inactivity and insulin use were all independently associated with the presence of DR. Furthermore, a secondary or higher educational level and obesity demonstrated independent and inverse associations with the development of DR.

Exploring the Impact of Glycemic Control on Diabetic Retinopathy: Emerging Models and Prognostic Implications

This review addresses the complexities of type 1 diabetes (T1D) and its associated complications, with a particular focus on diabetic retinopathy (DR). This review outlines the progression from non-proliferative to proliferative diabetic retinopathy and diabetic macular edema, highlighting the role of dysglycemia in the pathogenesis of these conditions. A significant portion of this review is devoted to technological advances in diabetes management, particularly the use of hybrid closed-loop systems (HCLSs) and to the potential of open-source HCLSs, which could be easily adapted to different patients' needs using big data analytics and machine learning. Personalized HCLS algorithms that integrate factors such as patient lifestyle, dietary habits, and hormonal variations are highlighted as critical to reducing the incidence of diabetes-related complications and improving patient outcomes.

Diabetic Retinopathy: Clinical Features, Risk Factors, and Treatment Options

Diabetic retinopathy is a common complication of diabetes that affects the eyes and can lead to severe vision loss or blindness if left untreated. Chronic hyperglycemia destroys the blood vessels in the retina, resulting in diabetic retinopathy. The damage can lead to leakage of fluid and blood into the retina, causing edema, hemorrhages, and ischemia. A thorough evaluation by an ophthalmologist is necessary to determine the most appropriate course of treatment for each patient with diabetic retinopathy. The article discusses various surgical treatment options for diabetic retinopathy, including vitrectomy, scleral buckling, epiretinal membrane peeling, retinal detachment repair, and the risk factors of diabetic retinopathy. These surgical techniques can help to address the underlying causes of vision loss and prevent further complications from developing or worsening. To avoid complications and maintain vision, this review emphasizes the significance of early detection and treatment of diabetic retinopathy. Patients with diabetic retinopathy can improve their eyesight and quality of life with the help of some surgical treatments. The article also highlights some case studies in the field of diabetic retinopathy.

Association between Glucose-lowering Treatments and Risk of Diabetic Retinopathy in People with Type 2 Diabetes: A Nationwide Cohort Study

INTRODUCTION

Glycaemic variability is possibly linked to the development of diabetic retinopathy, and newer second-line glucose-lowering treatments in type 2 diabetes might reduce glycaemic variability.

AIM

This study aimed to investigate whether newer second-line glucose-lowering treatments are associated with an alternative risk of developing diabetic retinopathy in people with type 2 diabetes.

METHODS

A nationwide cohort of people with type 2 diabetes on second-line glucose-lowering treatment regimens in 2008-2018 was extracted from the Danish National Patient Registry. Adjusted time to diabetic retinopathy was estimated with a Cox Proportional Hazards model. The model was adjusted for age, sex, diabetes duration, alcohol abuse, treatment start year, education, income, history of late-diabetic complications, history of non-fatal major adverse cardiovascular events, history of chronic kidney disease, and history of hypoglycaemic episodes.

RESULTS

Treatment regimens of metformin + basal insulin (HR: 3.15, 95% CI: 2.42-4.10) and metformin + glucagon-like peptide-1 receptor agonist (GLP-1-RA, HR: 1.46, 95% CI: 1.09-1.96) were associated with an increased risk of diabetic retinopathy compared with metformin + dipeptidyl peptidase-4 inhibitors (DPP-4i). Treatment with metformin + sodium-glucose cotransporter-2 inhibitor (SGLT2i, HR: 0.77, 95% CI: 0.28-2.11) was associated with the numerically lowest risk of diabetic retinopathy compared with all regimens investigated.

CONCLUSION

Findings from this study indicate that basal insulin and GLP-1-RA are suboptimal second- line choices for people with type 2 diabetes at risk of developing diabetic retinopathy. However, many other considerations concerning the choice of second-line glucose-lowering treatment for type 2 diabetes patients should be taken into account.

Bariatric surgery in individuals with type 2 diabetes is not associated with short or long-term risk of diabetic retinopathy progression: results from a nationwide cohort study

AIMS

Bariatric surgery is used to induce weight loss and glycemic stability in type 2 diabetes (T2D). It has been a concern that this may lead to early worsening of diabetic retinopathy (DR) due to a rapid decline in HbA1c. In this study, we evaluated the risk of short and long-term DR development and need for ocular intervention in an entire nation of individuals with T2D undergoing bariatric surgery.

METHODS

The study comprised a national, register-based cohort of individuals with T2D screened for DR. Cases were matched by age, sex and DR level at the date of surgery (index date) with non-bariatric controls. We extracted information on DR levels, in- and outpatient treatments, pharmaceutical prescriptions and laboratory values. We evaluated worsening of DR (incident and progressive DR) at follow-up (6 and 36 months).

RESULTS

Amongst 238,967 individuals with T2D, who attended diabetic eye screening, we identified 553 that underwent bariatric surgery (0.2%) and 2677 non-bariatric controls. Median age was 49 years, and 63% were female. Cases had more comorbidities, lower HbA1c as well as more frequent use of glucose-lowering and antihypertensive medication than controls at index date. In a fully adjusted logistic regression model, the risk of DR worsening for cases was not significantly different compared to controls, neither short-term (OR 0.41 [CI 95% 0.13; 1.33], p = 0.14) nor long-term (OR 0.64 [CI 95% 0.33; 1.24], p = 0.18).

CONCLUSIONS

In this nationwide study, bariatric surgery did not associate with increased risk of short- or long-term DR worsening.

Progress and indication for use of continuous glucose monitoring in patients with diabetes in pregnancy: a review

Gestational diabetes mellitus is one of the most common endocrine diseases that occur during pregnancy. Disorders of blood glucose metabolism during pregnancy can increase the risk of adverse pregnancy outcomes, such as pregnancy-related hypertension, preeclampsia, eclampsia, miscarriage, macrosomia, and neonatal hypoglycemia. Continuous glucose monitoring (CGM) can safely and effectively monitor blood glucose changes in patients with gestational hyperglycemia, thereby reducing adverse pregnancy outcomes. Hence, this article aimed to provide a comprehensive review of the progress and indications for using CGM in pregnant patients with diabetes. CGM can reduce blood glucose fluctuations and the occurrence of serious hypoglycemia and hyperglycemia events and can provide time in range (TIR). TIR is an important indicator of blood glucose level. Patients with a higher TIR during pregnancy have better gestational outcomes.

Pediatric Type 1 Diabetes: Mechanisms and Impact of Technologies on Comorbidities and Life Expectancy

Type 1 diabetes (T1D) is one of the most common chronic diseases in childhood, with a progressively increasing incidence. T1D management requires lifelong insulin treatment and ongoing health care support. The main goal of treatment is to maintain blood glucose levels as close to the physiological range as possible, particularly to avoid blood glucose fluctuations, which have been linked to morbidity and mortality in patients with T1D. Indeed, the guidelines of the International Society for Pediatric and Adolescent Diabetes (ISPAD) recommend a glycated hemoglobin (HbA1c) level < 53 mmol/mol (<7.0%) for young people with T1D to avoid comorbidities. Moreover, diabetic disease strongly influences the quality of life of young patients who must undergo continuous monitoring of glycemic values and the administration of subcutaneous insulin. In recent decades, the development of automated insulin delivery (AID) systems improved the metabolic control and the quality of life of T1D patients. Continuous subcutaneous insulin infusion (CSII) combined with continuous glucose monitoring (CGM) devices connected to smartphones represent a good therapeutic option, especially in young children. In this literature review, we revised the mechanisms of the currently available technologies for T1D in pediatric age and explored their effect on short- and long-term diabetes-related comorbidities, quality of life, and life expectation.

HIF-1α accumulation in response to transient hypoglycemia may worsen diabetic eye disease

Tight glycemic control (TGC), the cornerstone of diabetic management, reduces the incidence and progression of diabetic microvascular disease. However, TGC can also lead to transient episodes of hypoglycemia, which have been associated with adverse outcomes in patients with diabetes. Here, we demonstrate that low glucose levels result in hypoxia-inducible factor (HIF)-1-dependent expression of the glucose transporter, Glut1, in retinal cells. Enhanced nuclear accumulation of HIF-1α was independent of its canonical post-translational stabilization but instead dependent on stimulation of its translation and nuclear localization. In the presence of hypoxia, this physiologic response to low glucose resulted in a marked increase in the secretion of the HIF-dependent vasoactive mediators that promote diabetic retinopathy. Our results provide a molecular explanation for how early glucose control, as well as glycemic variability (i.e., oscillating serum glucose levels), contributes to diabetic eye disease. These observations have important implications for optimizing glucose management in patients with diabetes.

Nomogram for prediction of diabetic retinopathy in patients with type 2 diabetes mellitus: A retrospective study

OBJECTIVE

To develop a nomogram for the risk of diabetic retinopathy (DR) among type 2 diabetes mellitus (T2DM).

METHODS

Questionnaires, physical examinations and biochemical tests were performed on 5900 T2DM patients in the Second Hospital of Shijiazhuang. The least absolute shrinkage and selection operator regression was used to optimize feature selection, and the importance of selected features was analyzed by random forest. Logistic regression was performed with selected features, and the nomogram was established based on the results. The Harrell's C-statistic, bootstrap-corrected C-statistic, area under curve (AUC), calibration curve, decision curve analysis (DCA) and clinical impact curve (CIC) were used to validate the discrimination, calibration and clinical usefulness of the nomogram, and further assessment was running by external validation.

RESULTS

Predictors included duration of diabetes, diabetic neuropathy, diabetic kidney disease, diabetic foot, hyperlipidemia, hypoglycemic drugs, glycated albumin, Lactate dehydrogenase. The model displayed medium predictive power with a Harrell's C-statistic of 0.820, bootstrap-corrected C-statistic of 0.813 and AUC of 0.820 in the training set, and which was respectively 0.842, 0.835 and 0.842 in the validation set. The calibration curve displayed good agreement (P > 0.05). The DCA and CIC showed that the nomogram could be applied clinically if the risk threshold is between 2 % and 75 % and 2 %-88 % in validation set.

CONCLUSIONS

This nomogram incorporating 8 features is useful to predict the risk of DR in T2DM patients.

Endothelial Dysfunction and Platelet Hyperactivation in Diabetic Complications Induced by Glycemic Variability

The development and progression of the complications of chronic diabetes mellitus are attributed not only to increased blood glucose levels but also to glycemic variability. Therefore, a deeper understanding of the role of glycemic variability in the development of diabetic complications may provide more insight into targeted clinical treatment strategies in the future. Previously, the mechanisms implicated in glycemic variability-induced diabetic complications have been comprehensively discussed. However, endothelial dysfunction and platelet hyperactivation, which are two newly recognized critical pathogenic factors, have not been fully elucidated yet. In this review, we first evaluate the assessment of glycemic variability and then summarise the roles of endothelial dysfunction and platelet hyperactivation in glycemic variability-induced complications of diabetes, highlighting the molecular mechanisms involved and their interconnections.

Impact of anxiety, depression and disease-related distress on long-term glycaemic variability among subjects with Type 1 diabetes mellitus

BACKGROUND

Anxiety, depression, and disease-related distress are linked to worse overall glycaemic control, in terms of HbA1c. This study was aimed to evaluate whether traits of these emotional disorders are associated with long-term glycaemic variability in subjects with Type 1 diabetes.

METHODS

Longitudinal retrospective study. Six-year HbA1c data (2014-2019) from 411 subjects with Type 1 diabetes who had participated in a previous study to design a diabetes-specific quality of life questionnaire in the year 2014 were included. Scores for Spanish versions of the Hospital Anxiety and Depression Scale (HADS) and Problem Areas in Diabetes (PAID) scale were obtained at baseline, along with sociodemographic and clinical data. Long-term glycaemic variability was measured as the coefficient of variation of HbA1c (HbA1c-CV). The association between HADS and PAID scores and HbA1c-CV was analysed with Spearman correlations and multiple regression models, both linear and additive, including other covariates (age, sex, diabetes duration time, type of treatment, baseline HbA1c, use of anxiolytic or antidepressant drugs, education level and employment status).

RESULTS

Scores of depression, anxiety and distress were positively and significantly correlated to HbA1c-CV in univariate analyses. Multiple regression study demonstrated an independent association only for diabetes distress score (p < 0.001). Age, diabetes duration time, baseline HbA1c, education level and employment status were also significantly associated with HbA1c-CV. However, when subjects were analyzed separately in two age groups, distress scores were associated with HbA1c-CV only among those aged 25 years or older, while anxiety scores, but not distress, were associated with HbA1c-CV among those younger than 25 years.

CONCLUSIONS

Psychological factors, particularly disease-related distress and anxiety, are associated with long-term glycaemic variability in subjects with Type 1 diabetes.

Time in range measurements for hyperglycemia management during pregnancy

The prevalence of adverse pregnancy outcomes associated with poor glycemic control are increasing. Accordingly, effective blood glucose monitoring during pregnancy has become a subject of intense interest. Continuous glucose monitoring (CGM) displays dynamic changes in blood glucose by using probes to measure glucose concentration in the interstitial fluid, and the rapid development of CGM has enabled the investigation of time in range (TIR) in the glucose target range as a new parameter to evaluate blood glucose. International guidelines have identified TIR as an important blood glucose assessment method for pregnant patients with type 1 diabetes mellitus that overcomes the limitations of conventional gestational blood glucose monitoring, better reflects fluctuation in blood glucose during pregnancy, and effectively improves maternal and neonatal outcomes. However, there is little clinical evidence for the use of TIR in pregnant women with gestational diabetes mellitus and those with pre-pregnant type 2 diabetes mellitus. TIR is expected to become a critical indicator of blood glucose control and management in hyperglycemic pregnant patients. We review the research progress of TIR to help clinicians understand the field of blood glucose monitoring in pregnant women with hyperglycemia.

Can Resistance Exercise Be a Tool for Healthy Aging in Post-Menopausal Women with Type 1 Diabetes?

Due to improvements in diabetes care, people with type 1 diabetes (T1D) are living longer. Studies show that post-menopausal T1D women have a substantially elevated cardiovascular risk compared to those without T1D. As T1D may also accelerate age-related bone and muscle loss, the risk of frailty may be considerable for T1D women. Exercise and physical activity may be optimal preventative therapies to maintain health and prevent complications in this population: They are associated with improvements in, or maintenance of, cardiovascular health, bone mineral density, and muscle mass in older adults. Resistance exercise, in particular, may provide important protection against age-related frailty, due to its specific effects on bone and muscle. Fear of hypoglycemia can be a barrier to exercise in those with T1D, and resistance exercise may cause less hypoglycemia than aerobic exercise. There are currently no exercise studies involving older, post-menopausal women with T1D. As such, it is unknown whether current guidelines for insulin adjustment/carbohydrate intake for activity are appropriate for this population. This review focuses on existing knowledge about exercise in older adults and considers potential future directions around resistance exercise as a therapeutic intervention for post-menopausal T1D women.

Continuous subcutaneous insulin infusion therapy is associated with reduced retinopathy progression compared with multiple daily injections of insulin

AIMS/HYPOTHESIS

We aimed to compare diabetic retinopathy outcomes in people with type 1 diabetes following introduction of continuous subcutaneous insulin infusion (CSII) therapy with outcomes in people receiving continuing therapy with multiple daily insulin injections (MDI).

METHODS

This is a retrospective cohort study using the Scottish Care Information - Diabetes database for retinal screening outcomes and HbA_1c changes in 204 adults commenced on CSII therapy between 2013 and 2016, and 211 adults eligible for CSII during the same period but who continued on MDI therapy. Diabetic retinopathy progression (time to minimum one-grade worsening in diabetic retinopathy from baseline grading) was plotted for CSII and MDI cohorts using Kaplan-Meier curves, and outcomes were compared using multivariate Cox regression analysis adjusting for age, sex, baseline HbA_1c, blood pressure, cholesterol, smoking status and socioeconomic quintile. Impact of baseline HbA_1c and change in HbA_1c on diabetic retinopathy progression was assessed within CSII and MDI cohorts.

RESULTS

CSII participants were significantly younger, were from less socially deprived areas, and had lower HbA_1c and higher diastolic BP at baseline. There was a larger reduction in HbA_1c at 1 year in those on CSII vs MDI (-6 mmol/mol [-0.6%] vs -2 mmol/mol [-0.2%], p < 0.01). Diabetic retinopathy progression occurred in a smaller proportion of adults following commencement of CSII vs continued MDI therapy over mean 2.3 year follow-up (26.5% vs 18.6%, p = 0.0097). High baseline HbA_1c (75 mmol/mol [9%]) was associated with diabetic retinopathy progression in the MDI group (p = 0.0049) but not the CSII group (p = 0.93). Change in HbA_1c at follow-up, irrespective of baseline glycaemic status, did not significantly affect diabetic retinopathy progression in either group.

CONCLUSIONS/INTERPRETATION

CSII was associated with reduced diabetic retinopathy progression compared with continued MDI therapy, and may be protective against diabetic retinopathy progression for those with high baseline HbA_1c. Progression of diabetic retinopathy over 3 years was not associated with a change in HbA_1c.

Comparative effects of insulin glulisine and lispro on postprandial plasma glucose and lipid profile in Japanese patients with type 2 diabetes mellitus

Objective

The control of postprandial plasma glucose (PPG) excursions is critical in the prevention of diabetic complications. Controversy remains on the differences in postprandial actions of insulin glulisine and lispro. The aim of this study was to define the differences in the efficacy of these two insulin analogues on PPG.

Methods

The study subjects were 20 in-hospital patients with type 2 diabetes mellitus (T2DM). Plasma glucose (PG) was tightly controlled with basal insulin and insulin glulisine or lispro, and then glulisine or lispro were switched to the other insulin analog every other day for 6 study days. PG was measured before breakfast and 0.5-, 1-, and 2 h-postprandial during the study. Postprandial plasma C-peptide and lipids were analyzed in the first 2 days of the study. Postprandial increments in each parameter were compared between glulisine and lispro.

Results

Whereas the median value of 0.5 h-Δ-PPG was comparable in glulisine and lispro, the 1 h-Δ-PPG was significantly lower with lispro than with glulisine (41 vs 53 mg/dl, respectively, p = 0.03). Similarly, the 2 h-Δ-PPG with lispro was 10 mg/dl lower than that with glulisine (35 vs 45 mg/dl, respectively, p = 0.05). In parallel with PPG, Δ-C-peptide at 1- and 2 h-postprandial were significantly lower with lispro than glulisine (0.50 vs 0.75 ng/ml, respectively, and 0.55 vs 0.75 ng/ml, respectively). The increment in LDL-C and HDL-C was significantly lower with lispro than with glulisine at 0.5 h-postprandial.

Conclusion

Insulin lispro seems superior to glulisine in the control of PPG in Japanese patients with T2DM.

The relationship between glycemic variability and blood pressure variability in normoglycemic normotensive individuals

BACKGROUND AND AIM

Glycemic fluctuations around a mean glucose level, referred as glycemic variability and blood pressure variability (BPV) are considered as independent risk factors for cardiovascular diseases, all-cause mortality, and cardiovascular disease-mortality. With this background in mind, we aimed to investigate the association between glycemic variability and BPV and their association in normoglycemic and normotensive individuals.

MATERIALS AND METHOD

Twenty-seven normotensive normoglycemic individuals were recruited. Twenty-four hour Holter devices were utilized to measure ambulatory blood pressure (BP) while continuous glucose monitoring (CGM) devices were applied to measure glycemic variability simultaneously to the subjects. These devices were kept on for 48 h. For BP recordings, daytime, nighttime, and 24-h BP determinations, their mean and SD were calculated. From CGM measurements, mean blood glucose (MBG), SD of blood glucose, the mean amplitude of glycemic excursions (MAGE), the mean of daily differences (MODD), coefficient of variation (correction of variability for the MBG), and daytime and nighttime blood glucose were determined.

RESULTS

The mean age of the subjects was 23.8 ± 2.7 years and 66% were women (18/27). In the correlation analysis between glycemic variability parameters and BPV parameters, SD of 24-h SBP was correlated with the SD of MBG (r = 0.52, P = 0.006), MAGE (r = 0.49, P = 0.009), and MODD (r = 0.46, P = 0.015). SD of daytime SBP was correlated with, MAGE (r = 0.42, P = 0.03) and MODD (r = 0.43, P = 0.02).

CONCLUSION

We report correlation between glycemic variability and BPV variables in normoglycemic and normotensive healthy individuals.

Relationship between glycemic control and chronic obstructive pulmonary disease in patients with type 2 diabetes: A nested case-control study

AIMS

To evaluate the relationship between glycemic control and plasma glycated hemoglobin (HbA1c) levels in patients with type 2 diabetes mellitus (T2D) and the risk of chronic obstructive pulmonary disease (COPD).

METHODS

We conducted a population-based, retrospective, nested, case-control study involving 124,876 patients with DM2 from the Canary Islands, Spain. From the cohort, we selected all COPD cases and, for each case, five control subjects who were COPD free. We analyzed the association between glycemic control, HbA1c level and incident COPD.

RESULTS

A total of 1320 incidence cases of COPD (1.06%) were identified and matched individually with 6600 controls according to age and sex. After multivariate adjustment, the COPD risk increased among patients with poor glycemic control compared to patients with good glycemic control [HbA1c levels <7% (53 mmol/mol)] (OR 1.18; 95% CI: 1.03-1.36). In comparison with patients exhibiting HbA1c levels <7% (53 mmol/mol), the risk of COPD was higher among people with HbA1c levels of 7-8% (53-64 mmol/mol) (OR 1.24; 95% CI: 1.05-1.47) and 8-9% (64-75 mmol/mol) (OR 1.31; 95% CI: 1.04-1.66).

CONCLUSIONS

Poor glycemic control reveals a weak association with increased risk of COPD in T2D patients.

The effect of Sancai powder on glycemic variability of type 2 diabetes in the elderly: A randomized controlled trial

BACKGROUND

Type 2 diabetes is a kind of metabolic disease. Its clinical characteristic is hyperglycemia. Recently, more and more elderly people suffer from type 2 diabetes, and the glycemic variability of the elderly is greater. In addition, blood sugar variation is more likely to cause diabetes complications than simple hyperglycemia. Sancai podwer (SC) is based on the theory of traditional Chinese medicine and gradually formed in the summary of clinical experience. It has the effect of lowering blood sugar and alleviating clinical symptoms of diabetes. But the existing evidence of its efficacy on glycemic variability is insufficient. So, in our study, the randomized controlled trials will be used as a research method to explore the effects of SC on glycemic variability of type 2 diabetes.

METHOD

We will use randomized controlled experiments based on the recommended diagnostic criteria, inclusion and exclusion criteria. A total of 60 elderly patients with type 2 diabetes will be randomly divided into treatment group and control group, 30 cases in each group. The control group will receive conventional western medicine and the intervention group will receive SC combined with western medicine. The standard deviation and coefficient of variation of blood glucose level will be used as evaluation indexes.

DISCUSSION

This study can provide evidence for the clinical efficacy and safety of SC in elderly patients with type 2 diabetes mellitus.

TRIAL REGISTRATION

This study is registered on the Chinese Clinical Trial Registry: ChiCTR2000032611.

Suppression of HDAC by sodium acetate rectifies cardiac metabolic disturbance in streptozotocin-nicotinamide-induced diabetic rats

Diabetes mellitus, particularly type 2 occurs at global epidemic proportions and leads to cardiovascular diseases. Molecular studies suggest the involvement of epigenetic alterations such as histone code modification in the progression of cardiometabolic disorders. However, short chain fatty acids (SCFAs) are recognized as epigenetic modulators by their histone deacetylase inhibitory property. It is therefore hypothesized that cardiac histone deacetylase activity increases in type II diabetes and SCFA, acetate, would inhibit histone deacetylase with accompanying restoration of glucose dysregulation, cardiac lipid deposition, and tissue damage in male Wistar rats. Twenty-four male rats (240–270 g) were allotted into four groups ( n = 6 per group) namely: vehicle-treated ( p.o.), sodium acetate-treated (200 mg/kg), diabetic, and diabetic+sodium acetate-treated groups. Diabetes was induced by intraperitoneal injection of streptozotocin 65 mg/kg after a dose of nicotinamide 110 mg/kg. The results showed that diabetic rats had, glucose dysregulation, elevated serum and cardiac triglyceride, malondialdehyde, alanine aminotransferase, histone deacetylase, serum aspartate transaminase, cardiac low density lipoprotein cholesterol (LDLc), glutathione/glutathione disulphide ratio (GSH/GSSG), reduced serum and cardiac high density lipoprotein cholesterol (HDLc), and serum GSH/GSSG. Histological analysis revealed disrupted cardiac fiber in diabetic rats. However, sodium acetate attenuated glucose dysregulation and improved serum and cardiac GSH/GSSG. Sodium acetate normalized cardiac triglyceride accumulation, malondialdehyde, serum aspartate transaminase levels and prevented cardiac tissue damage in diabetic rats. These effects were associated with suppressed histone deacetylase activity. Therefore, sodium acetate attenuated but failed to normalize glucoregulation. Nevertheless, it ameliorated oxidative stress- and lipid dysmetabolism-driven cardiovascular complications in diabetic rats by the suppression of histone deacetylase activity.

Impact statement

This study provides evidence that STZ-NA-induced diabetes mellitus is associated with cardiac triglyceride accumulation and tissue disruption with corresponding increase in cardiac HDAC activity. However, sodium acetate suppresses cardiac HDAC activity and normalizes cardiac triglyceride and tissue integrity in diabetic rats. Therefore, the study suggests that sodium acetate is beneficial for cardioprotection in diabetes mellitus.

Efficacy of the Diabeloop closed-loop system to improve glycaemic control in patients with type 1 diabetes exposed to gastronomic dinners or to sustained physical exercise

AIMS

To compare closed-loop (CL) and open-loop (OL) systems for glycaemic control in patients with type 1 diabetes (T1D) exposed to real-life challenging situations (gastronomic dinners or sustained physical exercise).

METHODS

Thirty-eight adult patients with T1D were included in a three-armed randomized pilot trial (Diabeloop WP6.2 trial) comparing glucose control using a CL system with use of an OL device during two crossover 72-hour periods in one of the three following situations: large (gastronomic) dinners; sustained and repeated bouts of physical exercise (with uncontrolled food intake); or control (rest conditions). Outcomes included time in spent in the glucose ranges of 4.4-7.8 mmol/L and 3.9-10.0 mmol/L, and time in hypo- and hyperglycaemia.

RESULTS

Time spent overnight in the tight range of 4.4 to 7.8 mmol/L was longer with CL (mean values: 63.2% vs 40.9% with OL; P ≤ .0001). Time spent during the day in the range of 3.9 to 10.0 mmol/L was also longer with CL (79.4% vs 64.1% with OL; P ≤ .0001). Participants using the CL system spent less time during the day with hyperglycaemic excursions (glucose >10.0 mmol/L) compared to those using an OL system (17.9% vs 31.9%; P ≤ .0001), and the proportions of time spent during the day with hyperglycaemic excursions of those using the CL system in the gastronomic dinner and physical exercise subgroups were of similar magnitude to those in the control subgroup (18.1 ± 6.3%, 17.2 ± 8.1% and 18.4 ± 12.5%, respectively). Finally, times spent in hypoglycaemia were short and not significantly different among the groups.

CONCLUSIONS

The Diabeloop CL system is superior to OL devices in reducing hyperglycaemic excursions in patients with T1D exposed to gastronomic dinners, or exposed to physical exercise followed by uncontrolled food and carbohydrate intake.

Relationship of ankle-brachial index, vibration perception threshold, and current perception threshold to glycemic variability in type 2 diabetes

To explore the relationship of glycemic variability with lower extremity arterial disease (LEAD) and diabetic peripheral neuropathy (DPN).Seventy-eight patients with type 2 diabetes were enrolled. All patients underwent 72-hour dynamic blood glucose monitoring and obtained mean amplitude of glycemic excursions (MAGE), mean of daily differences (MODD), standard deviation of blood glucose (SD), largest amplitude of glycemic excursion (LAGE), mean blood glucose (MBG), T≥10.0 (percentage of time for blood glucose levels ≥10.0 mmol/L), T≤3.9 (percentage of time for blood glucose levels ≤3.9 mmol/L), and other glycemic variability parameters. In the meanwhile, in order to explore the correlation of glycemic variability parameters with ankle-brachial index (ABI), vibration perception threshold (VPT), and current perception threshold (CPT), all patients underwent quantitative diabetic foot screening, including ABI for quantitative assessment of lower extremity arterial lesions and VPT and CPT for quantitative assessment of peripheral neuropathy.Patients were divided into abnormal CPT group (n = 21) and normal CPT group (n = 57) according to the CPT values. Compared with the normal CPT group, abnormal CPT group showed significantly higher levels of HbA1c, longer duration of diabetes, and higher levels of T≤3.9 (P < .05). However, there was no significant difference of MAGE, SD, LAGE, MODD, and other glycemic variability parameters between abnormal CPT group and normal CPT group (P > .05). Pearson correlation analysis or Spearman correlation analysis showed that ABI negatively correlated with MBG, T≥10.0, SD, LAGE, and MAGE (P < .05), but no correlation of ABI with T≤3.9 and MODD (P > .05) was shown. VPT showed a positive correlation with T≥10.0 (P < .05), but no correlation with other glycemic variability parameters (P > .05). There was no correlation between the other CPT values and the glycemic variability parameters (P > .05), except that the left and right 250 Hz CPT values were positively correlated with T≤3.9 (P > .05).The higher the blood glucose levels, the severer the degree of LEAD and DPN lesions; the higher the incidence of hypoglycemia, the severer the degree of DPN lesions; the greater the fluctuation of blood glucose, the severer the degree of LEAD lesions. However, the glycemic variability was not significantly correlated with DPN.

Acute glycemic variability on admission predicts the prognosis in hospitalized patients with coronary artery disease: a meta-analysis

PURPOSE

Increased glycemic variability has been related with poor prognosis in patients with coronary artery disease (CAD). However, whether diabetic status or subtype of CAD could affect the association remains unknown. We performed a meta-analysis to systematically evaluate the association between the mean amplitude of glycemic excursions (MAGE) on continuous glucose monitoring and the incidence of major adverse cardiovascular events (MACEs) in CAD patients.

METHODS

Relevant prospective cohort studies were identified through search of PubMed, Embase, WanFang, and CNKI databases. A random-effect model was used to pool the results. Subgroup analyses were performed to evaluate the influences of the predefined study characteristics on the outcome.

RESULTS

Eleven cohort studies with 2666 hospitalized patients with acute coronary syndrome (ACS) or stable CAD for percutaneous coronary intervention were included. Pooled results showed that higher MAGE at admission was associated with higher incidence of MACEs during follow-up (adjusted relative risk [RR]: 1.84, p < 0.001; I² = 12%). Stratified analyses showed that the association between higher MAGE and higher risk of MACEs in CAD patients were consistent in patients with or without diabetes, and in those with ACS or stable CAD (p for subgroup difference both >0.05). Significant publication bias was detected (p = 0.041). Trim-and-fill analysis retrieved three studies to generate symmetrical funnel plots. Meta-analysis that incorporated these studies showed similar results (RR: 1.80, p < 0.001).

CONCLUSIONS

Increased glycemic variability may be associated with poor prognosis in CAD patients regardless of the diabetic status and the subtype of CAD.

Exhaled volatile substances in children suffering from type 1 diabetes mellitus: results from a cross-sectional study

Monitoring metabolic adaptation to type 1 diabetes mellitus in children is challenging. Analysis of volatile organic compounds (VOCs) in exhaled breath is non-invasive and appears as a promising tool. However, data on breath VOC profiles in pediatric patients are limited. We conducted a cross-sectional study and applied quantitative analysis of exhaled VOCs in children suffering from type 1 diabetes mellitus (T1DM) (n = 53) and healthy controls (n = 60). Both groups were matched for sex and age. For breath gas analysis, a very sensitive direct mass spectrometric technique (PTR-TOF) was applied. The duration of disease, the mode of insulin application (continuous subcutaneous insulin infusion vs. multiple daily insulin injection) and long-term metabolic control were considered as classifiers in patients. The concentration of exhaled VOCs differed between T1DM patients and healthy children. In particular, T1DM patients exhaled significantly higher amounts of ethanol, isopropanol, dimethylsulfid, isoprene and pentanal compared to healthy controls (171, 1223, 19.6, 112 and 13.5 ppbV vs. 82.4, 784, 11.3, 49.6, and 5.30 ppbV). The most remarkable differences in concentrations were found in patients with poor metabolic control, i.e. those with a mean HbA1c above 8%. In conclusion, non-invasive breath testing may support the discovery of basic metabolic mechanisms and adaptation early in the progress of T1DM.

Association of Retinopathy and Insulin Resistance: NHANES 2005-2008

Purpose: In animal models, insulin resistance without severe hyperglycemia is associated with retinopathy; however, corroborating data in humans are lacking. This study aims to investigate the prevalence of retinopathy in a population without diabetes and evaluate the association of insulin resistance and retinopathy within this group.Methods: The study population included 1914 adults age ≥40 without diabetes who were assigned to the morning, fasted group in the National Health and Nutrition Examination Survey 2005-2008, conducted by the Centers for Disease Control. Retinopathy was determined using fundus photos independently graded by a reading center and insulin resistance was determined using the homeostatic model of insulin resistance.Results: Prevalence of retinopathy in those without diabetes was survey design adjusted 9.4% (174/1914). In multivariable analyses, retinopathy was associated with insulin resistance (HOMA-IR OR: 1.09, 95% CI: 1.03, 1.16; p = .0030), male gender (OR: 1.39, 95% CI: 1.04, 1.85; p = .0267), and age (OR: 1.03, 95% CI: 1.01, 1.05; p = .0203).Conclusions: Insulin resistance in the absence of overt hyperglycemia could be an early driver of retinopathy.

The Relationship between Carotid Intima-Media Thickness and Ocular Circulation in Type-2 Diabetes

Purpose

To compare clinical findings, including ocular blood flow and intima-media thickness (IMT) of the carotid artery, in mild nonproliferative diabetic retinopathy (NPDR) and no diabetic retinopathy (NDR) patients, and to determine risk factors contributing to mild NPDR.

Methods

In 129 subjects (129 eyes) with type-2 diabetes patients and mild NPDR or NDR, standard statistical techniques were used to determine associations between clinical findings, including diabetes duration, blood levels of creatinine and hemoglobin A1c (HbA1c), central macular thickness (CMT; measured with optical coherence tomography), mean blur rate (MBR; measured with laser speckle flowgraphy), and ultrasound-measured carotid IMT.

Results

Diabetes duration, IMT, and CMT were significantly higher in the mild NPDR patients than the NDR patients (P=0.004, P=0.004, and P=0.003, respectively), while conversely, MBR in the overall optic nerve head (MBR-A) was lower in the mild NPDR patients. Furthermore, a logistic regression analysis showed that diabetes duration (OR, 1.11; P=0.006), diastolic blood pressure (OR, 0.93; P=0.025), heart rate (OR, 1.07; P=0.004), IMT (OR, 8.65; P=0.005), and CMT (OR, 1.03; P=0.007) were independent contributing factors to mild NPDR. Spearman's rank correlation test also showed that IMT was negatively correlated with MBR-A (P=0.011).

Conclusions

Increased IMT showed a close association with ocular ischemia in patients with type-2 diabetes and contributed to the presence of mild NPDR. These findings suggest that IMT may be an early biomarker of mild NPDR.

Longitudinal Relationship Between Retinal Diabetic Neurodegeneration and Progression of Diabetic Retinopathy in Patients With Type 2 Diabetes

PURPOSE

To investigate the longitudinal relationship between diabetic retinal neurodegeneration and the progression of diabetic retinopathy (DR) by measuring macular ganglion cell-inner plexiform layer (mGCIPL) thickness in patients with type 2 diabetes (T2DM).

DESIGN

Retrospective cohort study.

METHODS

T2DM patients with no DR or mild nonproliferative DR (NPDR) followed up for ≥4 years were included in this study. DR was graded according to retinal photography, and mean parafoveal mGCIPL thickness was measured using optical coherence tomography with at least a 6-month interval from baseline. Hazard ratios (HR) for predicting 2-step progression and development of proliferative DR (PDR) were calculated using Cox proportional hazard modeling using baseline clinical factors.

RESULTS

Of 87 eyes of T2DM patients, 39 (44.8%) exhibited 2-step DR progression and 6 (6.9%) experienced progression to PDR. Patients with DR progression exhibited longer T2DM duration, thinner mGCIPL, greater mGCIPL thinning rate, severe cardiac autonomic neuropathy (CAN), lower peripheral nerve-conduction velocity, and higher glycated hemoglobin A1c level. Multivariate regression modeling revealed that baseline mGCIPL thickness (HR = 0.94), mGCIPL thinning rate (HR = 1.924), CAN score (HR = 1.248), and conduction velocity of peripheral nerves (HR = 0.894) were significant predictive factors for DR progression (area under the curve = 0.92).

CONCLUSION

Progressive loss of mGCIPL is an independent risk factor for progression in early-stage DR. Further assessment of autonomic and peripheral nerve functions can increase sensitivity in predicting aggravation of DR in patients with T2DM.

Efficacy and safety of the artificial pancreas in the paediatric population with type 1 diabetes

BACKGROUND

Type 1 diabetes (DM1) is one of the most common chronic diseases in childhood and requires life-long insulin therapy and continuous health care support. An artificial pancreas (AP) or closed-loop system (CLS) have been developed with the aim of improving metabolic control without increasing the risk of hypoglycaemia in patients with DM1. As the impact of APs have been studied mainly in adults, the aim of this review is to evaluate the efficacy and safety of the AP in the paediatric population with DM1.

MAIN BODY

The real advantage of a CLS compared to last-generation sensor-augmented pumps is the gradual modulation of basal insulin infusion in response to glycaemic variations (towards both hyperglycaemia and hypoglycaemia), which has the aim of improving the proportion of time spent in the target glucose range and reducing the mean glucose level without increasing the risk of hypoglycaemia. Some recent studies demonstrated that also in children and adolescents an AP is able to reduce the frequency of hypoglycaemic events, an important limiting factor in reaching good metabolic control, particularly overnight. However, the advantages of the AP in reducing hyperglycaemia, increasing the time spent in the target glycaemic range and thus reducing glycated haemoglobin are less clear and require more clinical trials in the paediatric population, in particular in younger children.

CONCLUSIONS

Although the first results from bi-hormonal CLS are promising, long-term, head-to-head studies will have to prove their superiority over insulin-only approaches. More technological progress, the availability of more fast-acting insulin, further developments of algorithms that could improve glycaemic control after meals and physical activity are the most important challenges in reaching an optimal metabolic control with the use of the AP in children and adolescents.

Glycaemic variability-based classification of impaired glucose tolerance vs. type 2 diabetes using continuous glucose monitoring data

Many glycaemic variability (GV) indices extracted from continuous glucose monitoring systems data have been proposed for the characterisation of various aspects of glucose concentration profile dynamics in both healthy and non-healthy individuals. However, the inter-index correlations have made it difficult to reach a consensus regarding the best applications or a subset of indices for clinical scenarios, such as distinguishing subjects according to diabetes progression stage. Recently, a logistic regression-based method was used to address the basic problem of differentiating between healthy subjects and those affected by impaired glucose tolerance (IGT) or type 2 diabetes (T2D) in a pool of 25 GV-based indices. Whereas healthy subjects were classified accurately, the distinction between patients with IGT and T2D remained critical. In the present work, by using a dataset of CGM time-series collected in 62 subjects, we developed a polynomial-kernel support vector machine-based approach and demonstrated the ability to distinguish between subjects affected by IGT and T2D based on a pool of 37 GV indices complemented by four basic parameters-age, sex, BMI, and waist circumference-with an accuracy of 87.1%.

Nocturnal Hypoglycemia in Type 2 Diabetes

Background and aims: It is known that the majority of critical unacknowledged hypoglycemia has an increased incidence in patients with type 1 diabetes (T1DM) with a long evolution. The aim of this research is to evaluate the variability of glucose level and hypoglycemic events in patients with type 2 diabetes (T2DM) having pharmacological interventions with hypoglycemic risk. These events are sometimes asymptomatic also in T2DM: frequently in elderly, patients with autonomic neuropathy, or having a long evolution of disease.

Material and method: This analysis includes 72 patients with T2DM, with a relative good metabolic control, and possible glucose fluctuations. Glucose variability was appreciated using continuous glucose monitoring systems (CGMS) used for more than 72 hours in hospital or ambulatory setting.

Results: The incidence, duration and severity of hypoglycemia are not correlated with HbA1c value, age, disease duration or treatment. Approximately a quarter of patients had nocturnal hypoglycemia and in 37,5% of events hypoglycemia was prolonged, more 45 minutes. Clinical manifestations in diurnal hypoglycemia were presents in only 40% of the recorded events.

Conclusions: The study suggested that CGMS is beneficial for patients with type 2 diabetes, with hypoglycemic risk and complications, to adjusted medication, education and prevention the cardiovascular events.

Decreased Retinal Thickness in Type 1 Diabetic Children with Signs of Nonproliferative Diabetic Retinopathy

The retina functions as a neurovascular unit. How early vascular alterations affect neuronal layers remains controversial; early vascular failure could lead to edema increasing retinal thicknesses, but alternatively neuronal loss could lead to reduced retinal thickness. Objective. To evaluate retinal thickness in a cohort of pediatric patients with type 1 diabetes mellitus (PwT1DM) and to analyze differences according to the presence or absence of nonproliferative diabetic retinopathy (NPDR), poor metabolic control, and diabetes duration. Patients and Methods. We performed retinographies and optical coherence tomography (OCT) (TOPCON 3D1000®) to PwT1DM followed at our center and healthy controls. Measurements of the control group served to calculate reference values. Results. 59 PwT1DM (age 12.51 ± 2.59) and 22 healthy controls (age 10.66 ± 2.51) volunteered. Only two PwT1DM, both adolescents with poor metabolic control, presented NPRD. Both showed decreased thicknesses and retinal volumes. The odds ratio of having decreased retinal thickness when signs of NPDR were present was 11.72 (95% IC 1.16-118.28; p = 0.036). Conclusions. PwT1DM with NPDR have increased odds of decreased retinal thicknesses and volumes. Whether these changes are reversible by improving metabolic control or not remains to be elucidated.

Iminosugars Spiro-Linked with Morpholine-Fused 1,2,3-Triazole: Synthesis, Conformational Analysis, Glycosidase Inhibitory Activity, Antifungal Assay, and Docking Studies

Synthesis of iminosugars 1, 2, 3a, and 4a and N-alkyl (ethyl, butyl, hexyl, octyl, decyl, and dodecyl) derivatives 3b-g and 4b-g spiro-linked with morpholine-fused 1,2,3-triazole is described. Conformation of the piperidine ring in each spiro-iminosugar was evaluated by ¹H NMR spectroscopy, and conformational change in N-alkylated compounds 4b-g with respect to parent spiro-iminosugar 4a is supported by density functional theory calculations. Out of 16 new spiro-iminosugars, the spiro-iminosugars 3a (IC₅₀ = 0.075 μM) and 4a (IC₅₀ = 0.036 μM) were found to be more potent inhibitors of α-glucosidase than the marketed drug miglitol (IC₅₀ = 0.100 μM). In addition, 3a (minimum inhibition concentration (MIC) = 0.85 μM) and 4a (MIC = 0.025 μM) showed more potent antifungal activity against Candida albicans than antifungal drug amphotericin b (MIC = 1.25 μM). In few cases, the N-alkyl derivatives showed increase of α-glucosidase inhibition and enhancement of antifungal activity compare to the respective parent iminosugar. The biological activities were further substantiated by molecular docking studies.

Hemoglobin A1c Variability Predicts Symptoms of Depression in Elderly Individuals With Type 2 Diabetes

OBJECTIVE

This study aimed to analyze the relationship of variability in hemoglobin A_1c (HbA_1c) over years with subsequent depressive symptoms.

RESEARCH DESIGN AND METHODS

Subjects (n = 837) were participants of the Israel Diabetes and Cognitive Decline (IDCD) study, which aimed to examine the relationship of characteristics of long-term type 2 diabetes with cognitive decline. All pertain to a diabetes registry established in 1998, which contains an average of 18 HbA_1c measurements per subject. The results presented here are based on the IDCD baseline examination. Symptoms of depression were assessed using the 15-item version of the Geriatric Depression Scale (GDS). To quantify the association between variability in glycemic control (measured as the SD of HbA_1c measurements [HbA_1c-SD]) since 1998 with the number of depression symptoms at IDCD baseline, incidence rate ratios (IRRs) and corresponding 95% CIs were estimated via negative binomial regression modeling and used to account for the overdispersion in GDS scores.

RESULTS

Subjects' ages averaged 72.74 years (SD 4.63 years), and the mean number of years in the diabetes registry was 8.7 (SD 2.64 years). The mean GDS score was 2.16 (SD 2.26); 10% of subjects had a GDS score ≥6, the cutoff for clinically significant depression. Mean HbA_1c significantly correlated with HbA_1c-SD (r = 0.6625; P < 0.0001). The SD, but not the mean, of HbA_1c measurements was significantly associated with the number of subsequent depressive symptoms. For each additional 1% increase in HbA_1c-SD, the number of depressive symptoms increased by a factor of 1.31 (IRR = 1.31 [95% CI 1.03-1.67]; P = 0.03).

CONCLUSIONS

Variability in glycemic control is associated with more depressive symptoms.

Early short-term intensive multidisciplinary diabetes care: A ten-year follow-up of outcomes

OBJECTIVES

To evaluate the outcome of an early short-term intensive diabetic care program followed by a regular out-patient shared-care education program.

METHODS

We retrospectively reviewed the medical charts of 196 patients newly diagnosed with type 2 diabetes mellitus (DM) who were admitted to the hospital for intensive multidisciplinary interventions. For comparison, we also enrolled 206 patients with type 2 DM newly diagnosed but not receiving short-term intensive program. Both groups all attended an out-patient shared-care education program for more than one year. Outcome measure included average and standard deviation (SD) of glycated hemoglobin (HbA1c) over ten years, serum creatinine (Cr), lipid profile, urine albumin/Cr (UACR), and chronic diabetic complications after 10years later. The Kaplan-Meier event happening rates were used to compare the event rate of two samples. Multivariate Cox proportional-hazards models were used to investigate the influence of different variables on chronic complications.

RESULTS

Patients who received short-term intensive diabetic education had less SD of HbA1cs: (0.7±0.7% vs. 1.0±0.8% (5.3±5.3mmol/mol vs 9.2±6.4mmol/mol), p<0.001), less new-onset coronary heart disease (CHD) (8.2% vs. 13.7%, p=0.005), lower serum Cr (1.4±0.7mg/dL vs. 1.5±0.9mg/dL, p=0.005), less progression of nephropathy was also revealed (13.5% vs. 21.2%, p=0.009) and lower UACR (4.7±1.4mg/g vs. 5.3±1.0mg/g, p<0.001). There were no group differences in age, gender distribution, average HbA1c, lipid profile, and new-onset of neuropathy and retinopathy. The independent predictors of CHD and nephropathy were short-term intensive diabetic education and SD of HbA1cs.

CONCLUSION

Initiation of earlier intensive short-term multidisciplinary interventions in patients with newly diagnosed DM may decrease coronary heart disease and nephropathy. These better outcomes may be related to less fluctuation in blood glucose levels.

Greater HbA1c variability is associated with increased cardiovascular events in type 2 diabetes patients with preserved renal function, but not in moderate to advanced chronic kidney disease

Emerging evidence suggests that glycemic variability may be a more reliable measure of glycemic control than mean HbA1c in type 2 diabetes mellitus. This study aimed to determine if HbA1c variability is associated with cardiovascular events in type 2 diabetic patients and if different renal functions affect such association. This longitudinal study enrolled 8259 diabetic patients from the Kaohsiung Medical University Research Database in 2009 and were followed-up until 2015. Intra-individual HbA1C variability was defined as the standard deviation (SD) of HbA1c and cardiovascular events were defined as hospitalization for coronary artery disease, unstable angina, myocardial infarction, stroke, peripheral artery disease, and cardiovascular death. The patients were grouped into two based on their estimated glomerular filtration rate (eGFR) ≥ 60 or < 60 min/ml/1.73m2. In a mean follow-up period of 6.3 years, cardiovascular events were recorded in 8.9% of the patients. In an adjusted Cox model, high HbA1c SD (hazard ratio, 1.290; 95% confidence interval, 1.008-1.650; p = 0.043), but not mean HbA1c, was associated with significantly increased risk of cardiovascular events in patients with eGFR ≥ 60 min/ml/1.73m2. This association was not seen in patients with eGFR < 60 min/ml/1.73m2. In this study, greater HbA1c variability is associated with increased risk of cardiovascular among patients with preserved renal function, but not in those with moderate to advanced chronic kidney disease.

Twenty-four-hour variations in blood glucose level in Japanese type 2 diabetes patients based on continuous glucose monitoring

Aims/Introduction

High fluctuations in blood glucose are associated with various complications. The correlation between glycated hemoglobin (HbA1c) level and fluctuations in blood glucose level has not been studied in Japanese patients with type 2 diabetes. In the present study, blood glucose profile stratified by HbA1c level was evaluated by continuous glucose monitoring (CGM) in Japanese type 2 diabetes patients.

Materials and Methods

Our retrospective study included 294 patients with type 2 diabetes who were divided by HbA1c level into five groups (≥6.0 to <7.0%, ≥7.0 to <8.0%, ≥8.0 to <9.0%, ≥9.0 to <10.0% and ≥10%). The correlation between HbA1c level and CGM data was analyzed. The primary end‐point was the difference in blood glucose fluctuations among the HbA1c groups.

Results

The mean blood glucose level increased significantly with increasing HbA1c (P_trend < 0.01). The standard deviation increased with increases in HbA1c (P_trend < 0.01). The mean amplitude of glycemic excursions did not vary significantly with HbA1c. The levels of maximum blood glucose, minimum blood glucose, each preprandial blood glucose, each postprandial maximum blood glucose, range of increase in postprandial glucose from pre‐meal to after breakfast, the area under the blood concentration–time curve >180 mg/dL and percentage of the area under the blood concentration–time curve >180 mg/dL were higher with higher HbA1c. Mean glucose level and pre‐breakfast blood glucose level were significant and independent determinants of HbA1c.

Conclusions

In Japanese patients treated for type 2 diabetes, the mean amplitude of glycemic excursions did not correlate with HbA1c, making it difficult to assess blood glucose fluctuations using HbA1c. Parameters other than HbA1c are required to evaluate fluctuations in blood glucose level in patients receiving treatment for type 2 diabetes.

Diabetic macular oedema: clinical risk factors and emerging genetic influences

Diabetic macular oedema is the major cause of visual impairment in type 1 and type 2 diabetes. As type 2 diabetes becomes more prevalent worldwide, the prevalence of diabetic macular oedema is also expected to rise. Current management of diabetic macular oedema is challenging, expensive and not optimal in a subset of patients. Therefore, it is important to increase our understanding of the risk factors involved and develop preventative strategies. While clinical risk factors for diabetic macular oedema have been identified, few studies have addressed potential genetic risk factors. Epidemiology and family studies suggest genetic influences are of importance. In this review, we summarise known clinical risk factors, as well as discuss the small number of genetic studies that have been performed for diabetic macular oedema.

HbA1c, systolic blood pressure variability and diabetic retinopathy in Asian type 2 diabetics

BACKGROUND

The aim of the present study was to examine the association between variability in HbA1c or systolic blood pressure (SBP) and diabetes-specific moderate retinopathy in Asians with type 2 diabetes (T2D).

METHODS

A retrospective study was conducted of 172 cases of moderate diabetic retinopathy (DR) cases and 226 controls without DR, matched for age, sex, and ethnicity. Serial HbA1c and SBP (range 3-6 readings) over the 2 years prior to photographic screening of DR were collected. Intrapersonal mean and SD values for HbA1c (iM-HbA1c and iSD-HbA1c) and SBP (iM-SBP and iSD-SBP) were derived. Moderate DR was assessed from digital retinal photographs and defined as levels >43 using the Early Treatment Diabetic Retinopathy Study scale.

RESULTS

Cases of moderate DR had higher iM-HbA1c (8.2 % vs 7.3 %; P = 0.001), iSD-HbA1c (1.22 vs 0.64; P = 0.001), iM-SBP (136.8 vs 129.6 mmHg; P = 0.001) and iSD-SBP (13.3 vs 11.1; P = 0.002) than controls. In the multivariate regression model adjusted for age, gender, ethnicity, duration of diabetes, SBP, and HbA1c, iM-HbA1c and iM-SBP were significantly associated with moderate DR (odds ratio [OR] 1.80, 95 % confidence interval [CI] 1.37-2.36; and OR 1.03, 95 % CI 1.01-1.05, respectively). Neither iSD-HbA1c nor iSD-SBP were associated with moderate DR. When stratified by HbA1c <7 %, only iSD-SBP remained significantly associated with moderate DR (OR 1.11, 95 % CI 1.01-1.21).

CONCLUSION

In a cohort of Asian patients with T2D, both higher mean HbA1c levels and SBP, but not their variability, were associated with moderate DR. Among those with good glycemic control, wider variability of SBP is associated with moderate DR.

The TetO rat as a new translational model for type 2 diabetic retinopathy by inducible insulin receptor knockdown

AIMS/HYPOTHESIS

Although the renin-angiotensin system plays an important role in the progression of diabetic retinopathy, its influence therein has not been systematically evaluated. Here we test the suitability of a new translational model of diabetic retinopathy, the TetO rat, for addressing the role of angiotensin-II receptor 1 (AT1) blockade in experimental diabetic retinopathy.

METHODS

Diabetes was induced by tetracycline-inducible small hairpin RNA (shRNA) knockdown of the insulin receptor in rats, generating TetO rats. Systemic treatment consisted of an AT1 blocker (ARB) at the onset of diabetes, following which, 4-5 weeks later the retina was analysed in vivo and ex vivo. Retinal function was assessed by Ganzfeld electroretinography (ERG).

RESULTS

Retinal vessels in TetO rats showed differences in vessel calibre, together with gliosis. The total number and the proportion of activated mononuclear phagocytes was increased. TetO rats presented with loss of retinal ganglion cells (RGC) and ERG indicated photoreceptor malfunction. Both the inner and outer blood-retina barriers were affected. The ARB treated group showed reduced gliosis and an overall amelioration of retinal function, alongside RGC recovery, whilst no statistically significant differences in vascular and inflammatory features were detected.

CONCLUSIONS/INTERPRETATION

The TetO rat represents a promising translational model for the early neurovascular changes associated with type 2 diabetic retinopathy. ARB treatment had an effect on the neuronal component of the retina but not on the vasculature.

Zerumbone, a Phytochemical of Subtropical Ginger, Protects against Hyperglycemia-Induced Retinal Damage in Experimental Diabetic Rats

Diabetic retinopathy (DR), the most ordinary and specific microvascular complication of diabetes, is a disease of the retina. Zerumbone (ZER) is a monocyclic sesquiterpene compound, and based on reports, it is the predominant bioactive compound from the rhizomes of Zingiber zerumbet. The aim of the current study is to evaluate the protective effect of zerumbone against DR in streptozotocin (STZ)-induced diabetic rats. STZ-diabetic rats were treated with ZER (40 mg/kg) once a day orally for 8 weeks. ZER administration significantly (p < 0.05) lowered the levels of plasma glucose (32.5% ± 5.7% lower) and glycosylated hemoglobin (29.2% ± 3.4% lower) in STZ-diabetic rats. Retinal histopathological observations indicated that disarrangement and reduction in thickness of retinal layers were reversed in ZER-treated diabetic rats. ZER downregulated both the elevated levels of advanced glycosylated end products (AGEs) and the higher levels of the receptors for AGEs (RAGE) in retinas of diabetic rats. What's more, ZER significantly (p < 0.05) ameliorated diabetes-induced upregulation of tumor necrosis factor-α, interleukin (IL)-1 and IL-6. ZER also attenuated overexpression of vascular endothelial growth factor and intercellular adhesion molecule-1, and suppressed activation of nuclear factor (NF)-κB and apoptosis in the retinas of STZ-diabetic rats. Our results suggest ZER possesses retinal protective effects, which might be associated with the blockade of the AGEs/RAGE/NF-κB pathway and its anti-inflammatory activity.

The association of serum glycated albumin with the prevalence of diabetic retinopathy in Korean patients with type 2 diabetes mellitus

AIMS

To determine the clinical relationship between serum glycated albumin (GA) and diabetic retinopathy in Korean patients with type 2 diabetes mellitus (T2DM).

METHODS

A cross-sectional study including 424 patients with T2DM was conducted. Patients were divided into groups based on the presence of diabetic retinopathy and tertiles of serum GA and 1,5-anhydroglucitol levels.

RESULTS

Patients in the highest tertile of GA had a higher risk of diabetic retinopathy than those in the lowest tertile. Further analysis divided the groups based on glycated hemoglobin (HbA1c) levels, either above or below 8% (64mmol/mol), and revealed that in those with a HbA1c below 8% (64mmol/mol), the higher GA subgroup had an increased presence of diabetic retinopathy.

CONCLUSIONS

An increased GA level was significantly correlated with the presence of diabetic retinopathy, and measuring GA levels in addition to HbA1c was beneficial as a marker for retinopathy, especially in patients with moderate glycemic control.

Glucose variability, HbA1c and microvascular complications

Microvascular complications in diabetes are associated with poor long-term diabetes control as measured by HbA1c levels. Glucose fluctuations are related to oxidative stress, endothelial dysfunction, and inflammation, factors traditionally associated with the pathogenesis of vascular damage. Glucose variability has been associated with macrovascular disease in some studies but any association with microvascular disease remains controversial. This overview summarizes recent findings in the field of glucose variability and its possible relationship with retinopathy, nephropathy and neuropathy. It is concluded that randomized prospective follow-up trials could possibly help estimate whether short-term glucose variability should be considered as an independent risk factor for microvascular complications in diabetes.

"Dual-remission" after Roux-en-Y gastric bypass surgery: Glycemic variability cannot always be improved in Chinese obese patients with type 2 diabetes

BACKGROUND

Glycemic variability after Roux-en-Y Gastric Bypass (RYGB) has not been adequately examined in Chinese obese patients with type 2 diabetes (T2D).

OBJECTIVE

We aimed to evaluate glucose variability after RYGB by continuous glucose monitoring (CGM) and then evaluate the remission rate based on the complete diabetes remission criteria combined with normal ranges of CGM for the Chinese population, which we defined as "dual-remission."

SETTING

The study was done at our academic university-affiliated hospital.

METHODS

Over a 3-day period, CGM was performed on 43 Chinese obese T2D patients combined with a mixed-meal test before and 1 year after RYGB. Mean amplitude of glucose excursions (MAGE), standard deviations (SD), and the time that patients' blood glucose levels were≥7.0 mmol/L,≥7.8 mmol/L,≥11.1 mmol/L, and≤3.9 mmol/L within 24 hours was analyzed. Multiple logistic regression analyses were used to identify predictors of "dual-remission."

RESULTS

Complete diabetes remission was achieved in 27 patients (62.8%) 1 year after RYGB. However, MAGE didn't change in the group, and only 18.6% patients met "dual-remission." Compared with patients in the complete remission group, patients in the dual-remission group had a shorter duration of diabetes, younger age, lower glycated hemoglobin (HbA1c) level, and no insulin usage at baseline. Correlation analysis showed MAGE after RYGB was positively correlated with diabetes duration (r = .43, P<.01). Multiple logistic regressions indicated a shorter duration was associated with a higher possibility to achieve dual-remission after adjusting for age, gender, HbA1c, and insulin therapy.

CONCLUSION

Glucose variability can't be effectively improved in most Chinese obese diabetic patients after RYGB. Shorter diabetes duration was associated with higher possibility to achieve "dual-remission."

Glycemic Variability: How Do We Measure It and Why Is It Important?

Chronic hyperglycemia is the primary risk factor for the development of complications in diabetes mellitus (DM); however, it is believed that frequent or large glucose fluctuations may independently contribute to diabetes-related complications. Postprandial spikes in blood glucose, as well as hypoglycemic events, are blamed for increased cardiovascular events in DM. Glycemic variability (GV) includes both of these events; hence, minimizing GV can prevent future cardiovascular events. Correcting GV emerges as a target to be pursued in clinical practice to safely reduce the mean blood glucose and to determine its direct effects on vascular complications in diabetes. Modern diabetes management modalities, including glucagon-related peptide-1-based therapy, newer insulins, modern insulin pumps and bariatric surgery, significantly reduce GV. However, defining GV remains a challenge primarily due to the difficulty of measuring it and the lack of consensus regarding the optimal approach for its management. The purpose of this manuscript was not only to review the most recent evidence on GV but also to help readers better understand the available measurement options and how the various definitions relate differently to the development of diabetic complications.