Acute-phase glucose fluctuation is negatively correlated with myocardial salvage after acute myocardial infarction

Effect of 24 h glucose fluctuations on 30-day and 1-year mortality in patients with acute myocardial infarction: an analysis from the MIMIC-III database

Background

It is recognized that patients' blood glucose fluctuates over time during acute disease episodes, especially during the outbreak of cardiovascular events, regardless of the presence of an abnormal blood glucose profile prior to admission to the hospital. Glucose fluctuations in patients with acute myocardial infarction (AMI) in the intensive care unit (ICU) are currently not adequately monitored and studied. We focused on blood glucose fluctuation values within 24 h of admission to assess their association with 30-day and 1-year mortality.

Methods

Data of patients with AMI aged 18 years or older from the Critical Care Medical Information Marketplace database III V1.4 were available for analysis in this research. Glucose data were obtained by measurement. A total of 390 of them were treated with PCI. The principal consequence was 30-day and 1-year mortality in patients with AMI. The effect of different glucose fluctuations within 24 h of admission on mortality was predicted by constructing a multivariate Cox regression model with four model adjustments and Kaplan-Meier survival curves. Additionally, we performed curve-fitting analyses to show the correlation between blood glucose fluctuations and risk of death.

Results

We selected 1,699 AMI patients into our study through screening. The included population was categorized into three groups based on the tertiles of blood glucose fluctuation values within 24 h of admission to the ICU. The three groups were <25 mg/dl, 25-88 mg/dl and >88 mg/dl. By cox regression analysis, the group with the highest blood glucose fluctuation values (>88 mg/dl) had the most significant increase in 30-day and 1-year mortality after excluding confounding factors (30-day mortality adjusted HR = 2.11; 95% CI = 1.49-2.98 p < 0.001; 1-year mortality adjusted HR = 1.83; 95% CI = 1.40-2.39 p < 0.001). As demonstrated by the Kaplan-Meier survival curves, the group with the greatest fluctuations in blood glucose has the worst 30-day and 1-year prognosis.

Conclusions

The extent of glucose fluctuations in patients with AMI in the first 24 h after ICU admission is an essential predictor as to 30-day as well as 1-year mortality. When blood glucose fluctuates more than 88 mg/dl within 24 h, mortality increases significantly with the range of blood glucose fluctuations.

Glycaemic control in people with diabetes following acute myocardial infarction

Diabetes is a highly prevalent disease associated with considerable cardiovascular end organ damage and mortality. Despite significant changes to the management of acute myocardial infarction over the last two decades, people with diabetes remain at risk of complications and mortality following a myocardial infarct for a multitude of reasons, including increased coronary atherosclerosis, associated coronary microvascular dysfunction, and diabetic cardiomyopathy. Dysglycaemia causes significant endothelial dysfunction and upregulation of inflammation within the vasculature and epigenetic changes mean that these deleterious effects may persist despite subsequent efforts to tighten glycaemic control. Whilst clinical guidelines advocate for the avoidance of both hyper- and hypoglcyaemia in the peri-infarct period, the evidence base is lacking, and currently there is no consensus on the benefits of glycaemic control beyond this period. Glycaemic variability contributes to the glycaemic milieu and may have prognostic importance following myocardial infarct. The use of continuous glucose monitoring means that glucose trends and parameters can now be captured and interrogated, and its use, along with newer medicines, may provide novel opportunities for intervention after myocardial infarction in people with diabetes.

Short-term Glycemic Variability and Its Association With Macrovascular and Microvascular Complications in Patients With Diabetes

The introduction of continuous glucose monitoring inaugurated a new era in clinical practice by shifting the characterization of glycemic control from HbA1c to novel metrics. The one that gained widespread attention over the past decades was glycemic variability (GV), which typically refers to peaks and nadirs of blood glucose measured over a given time interval. GV can be dichotomized into two main categories: short-term and long-term. Short-term GV reflects within-day and between-day glycemic oscillations, and its contribution to diabetic complications remains an enigma. In this review, we summarize the available data about short-term GV and its possible association with both microvascular and macrovascular complications, evaluating different pathogenic mechanisms and demonstrating nonpharmaceutical, as well as pharmaceutical, therapeutic interventions.

Relation of glucose variability to vulnerable plaque formation in patients with coronary artery disease

BACKGROUND

Although glucose variability (GV) is reportedly associated with coronary plaque vulnerability, namely lipid-rich plaque, details are not fully understood. The aim of this study was to evaluate relations of GV after discharge to vulnerable plaque formation assessed by near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) in patients with and without diabetes.

METHODS

A total of 40 patients undergoing percutaneous coronary intervention under NIRS-IVUS guidance were included, among whom 13 (33%) had diabetes and 20 (50%) presented with acute myocardial infarction (MI). GV was evaluated by a flush glucose monitoring system, primarily with mean amplitude of glycemic excursion (MAGE). Lipid-rich plaque was assessed by maximum lipid core burden index in 4 mm (maxLCBI_4mm) in the target lesion using NIRS-IVUS.

RESULTS

Mean MAGE and maxLCBI_4mm were 69.7 ± 25.6 mg/dl and 508.0 ± 294.9. Intra-day GV was not significantly associated with maxLCBI_4mm in the entire study population, while MAGE was correlated with maxLCBI_4mm in non-diabetic patients (r = 0.46, p = 0.02). In patients with and without acute MI presentation, no significant relations were found between MAGE and maxLCBI_4mm.

CONCLUSION

GV was associated with lipid core plaque formation, especially in non-diabetic patients.

Association between Changes in the Systolic Blood Pressure from Evening to the Next Morning and Night Glucose Variability in Heart Disease Patients

Objectve To assess the impact of glycemic variability on blood pressure in hospitalized patients with cardiac disease. Methods In 40 patients with cardiovascular disease, the glucose levels were monitored by flash continuous glucose monitoring (FGM; Free-Style Libre™ or Free-Style Libre Pro; Abbott, Witney, UK) and self-monitoring blood glucose (SMBG) for 14 days. Blood pressure measurements were performed twice daily (morning and evening) at the same time as the glucose level measurement using SMBG. Results The detection rate of hypoglycemia using the FGM method was significantly higher than that with the 5-point SMBG method (77.5% vs. 5.0%, p<0.001). Changes in the systolic blood pressure from evening to the next morning [morning - evening (ME) difference] were significantly correlated with night glucose variability (r=0.63, P<0.001). A multiple regression analysis showed that night glucose variability using FGM was more closely correlated with the ME difference [r=0.62 (95% confidence interval, 0.019-0.051); p<0.001] than with the age, body mass index, or smoking history. Night glucose variability was also more closely associated with the ME difference in patients with unstable angina pectoris (UAP) than in those with acute myocardial infarction (AMI) or heart failure (HF) (r=0.83, p=0.058). Conclusion Night glucose variability is associated with the ME blood pressure difference, and FGM is more accurate than the 5-point SMBG approach for detecting such variability.

Significance of day-to-day glucose variability in patients after acute coronary syndrome

Background

Several studies have recently addressed the importance of glycemic variability (GV) in patients with acute coronary syndrome (ACS). Although daily GV measures, such as mean amplitude of glycemic excursions, are established predictors of poor prognosis in patients with ACS, the clinical significance of day-to-day GV remains to be fully elucidated. We therefore monitored day-to-day GV in patients with ACS to examine its significance.

Methods

In 25 patients with ACS, glucose levels were monitored for 14 days using a flash continuous glucose monitoring system. Mean of daily differences (MODD) was calculated as a marker of day-to-day GV. N-terminal pro-brain natriuretic peptide (NT-proBNP) was evaluated within 4 days after hospitalization. Cardiac function (left ventricular end-diastolic volume, left ventricular ejection fraction, stroke volume) was assessed by echocardiography at 3–5 days after admission and at 10–12 months after the disease onset.

Results

Of the 25 patients, 8 (32%) were diagnosed with diabetes, and continuous glucose monitoring (CGM)-based MODD was high (16.6 to 42.3) in 17 patients (68%). Although MODD did not correlate with max creatine kinase (CK), there was a positive correlation between J-index, high blood glucose index, and NT-proBNP (r = 0.83, p < 0.001; r = 0.85, p < 0.001; r = 0.41, p = 0.042, respectively).

Conclusions

In patients with ACS, MODD was associated with elevated NT-proBNP. Future studies should investigate whether day-to-day GV in ACS patients can predict adverse clinical events such as heart failure.

Coronary Flow Reserve and Glycemic Variability in Patients with Coronary Artery Disease

Objective Glycemic variability is being increasingly recognized as an early indicator of glucose metabolic disorder and may contribute to the development of diabetic vascular complications, such as coronary microvascular dysfunction. The present study sought to investigate the relationship between coronary microvascular function assessed by intracoronary thermodilution method and glycemic variability on a continuous glucose monitoring system (CGMS). Methods We prospectively enrolled 40 patients with or without known diabetes mellitus who had epicardial coronary artery disease referred for coronary angiography and were not treated with diabetic medications. Of these, two had a significant stenosis in the left main coronary artery and were therefore excluded from the analyses. In the end, 38 patients were equipped with a CGMS and underwent intracoronary physiological assessments in the unobstructed left anterior descending artery. The mean amplitude of glycemic excursion (MAGE) and standard deviation were calculated from the obtained CGMS data as indicators of glucose variability. Results Coronary flow reserve (CFR) was negatively correlated with MAGE (r=-0.328, p=0.044) and standard deviation (r=-0.339, p=0.037) on CGMS, while the index of microcirculatory resistance showed no such correlation. Multivariable linear regression analyses showed that MAGE on CGMS was significantly associated with CFR after adjusting for age, sex, fractional flow reserve and hemoglobin A1c. Conclusion Higher MAGE on CGMS was associated with reduced CFR in stable patients with coronary artery disease, suggesting a potential effect of glycemic variability on coronary microvascular flow regulation. A further study with a larger sample size needs to be conducted to confirm our findings.

Intervention by clinical pharmacists can improve blood glucose fluctuation in patients with diabetes and acute myocardial infarction: A propensity score-matched analysis

Acute phase hyperglycemia and exaggerated glucose fluctuation may be associated with poor outcomes in diabetic patients after acute myocardial infarction (AMI). This study aimed to determine whether intervention by clinical pharmacists can mitigate blood glucose and glucose fluctuations in these fragile patients. This retrospective study enrolled patients with diabetes and AMI, from 1 January 2019 to 30 June 2020 in our institution. Blood glucose and glucose fluctuations were calculated before and after the pharmacist's intervention and between patients who underwent intervention and those who did not. Propensity score matching (PSM) was used to reduce the impact of patient characteristics on the results. A total of 170 patients were included in our primary analysis, including 29 patients who received the pharmacist intervention and 141 patients who did not. After the pharmacist's intervention, blood glucose (fasting blood glucose-FBG, from 11.9 to 9.8; postprandial blood glucose-PBG, from 15.3 to 13.2; mean blood glucose-BG, 14.5 to 12.3 mmol/L; p < .001), and glucose fluctuations (standard deviation of blood glucose-SDBG, from 3.8 to 3.0, mmol/L, p = .005) were significantly improved. Before PSM, no clear effects were found in intervention versus nonintervention patients, in terms of blood glucose and glucose fluctuation indicators, except for FBG (9.3 vs. 8.0. mmol/L, p = .005). Further analysis indicated a high incidence of FBG <7.8 mmol/L in nonintervention versus intervention patients (51.5% vs. 27.6%, p = .003). After PSM, a significant reduction in blood glucose fluctuation (SDBG, 3.0 vs. 4.1, p = .031; PBGE, 2.1 vs. 4.1, p = .017; LAGE, 4.7 vs. 7.2, mmol/L, p = .004), and PBG (11.1 vs. 13.0, mmol/L, p = .048) was observed in the intervention group than in the nonintervention group. The clinical pharmacist intervention contributed to improved outcomes, specifically, in reducing blood glucose fluctuations and potential hypoglycemia risk.

Single prognostic cut-off value for admission glycemia in acute myocardial infarction has been used although high-risk stems from hyperglycemia as well as from hypoglycemia (a narrative review)

All original articles and meta-analysis use the single cut-off value to distinguish high-risk hyperglycemic from other acute myocardial infarction (AMI) patients. The mortality rate is 3.9 times higher in non-diabetic AMI patients with admission glycemia ≥6.1mmol compared to normoglycemic non-diabetic AMI patients. On the other hand, admission hypoglycemia in AMI is an important predictor of mortality. Because both admission hypo- and hyperglycemia correspond to higher in-hospital mortality, this graph is recognized as "J or U shaped curve". The review suggests two cut-off values for admission glycemia for risk assessment in AMI instead of single one because hypoglycemia as well as hyperglycemia represents a high-risk factor.

Glycaemic variability is associated with severity of coronary artery disease in patients with poorly controlled type 2 diabetes and acute myocardial infarction

BACKGROUND

In patients with type 2 diabetes (T2D), glycaemic variability (GV), another component of glycaemic abnormalities, is a novel potentially aggravating factor for coronary artery disease (CAD).

OBJECTIVES

The aim of our study was to identify interactions between GV and severity of CAD in diabetes patients admitted for acute myocardial infarction (AMI).

METHODS

All patients with T2D admitted to our university hospital for AMI from March 2015 to February 2017 who received intravenous (IV) insulin therapy and underwent coronary angiography were included. GV was assessed by mean amplitude of blood glucose excursion (MAGE) values taken within 2 days of admission. Patients with higher GV (highest MAGE tertile) were compared with those with lower GV (first and second MAGE tertiles).

RESULTS

A total of 204 patients were included: median age was 72 (61-81) years; 32% were female; HbA_1c was 7.3% (6.4-8.2%); diabetes duration was 10 (2-17.5) years; and MAGE value was 0.65 (0.43-0.92) g/L. Compared with those with lower GV, patients with the highest GV were more often women, treated with previous insulin, and had higher blood glucose and HbA_1c levels. In addition, patients with elevated GV had significantly higher SYNTAX scores: 17 (10-28) vs. 12 (6-22) (P = 0.009). Indeed, SYNTAX scores (OR: 1.05, 95% CI: 1.02-1.08; P = 0.001) remained independently associated with high GV beyond HbA_1c levels (OR: 1.51, 95% CI: 1.2-1.89; P <  0.001).

CONCLUSION

In AMI patients with poorly controlled diabetes, GV is associated with CAD severity beyond chronic hyperglycaemia. Although no causality can be determined from our observational study, the results suggest that, in AMI, early evaluation of GV might contribute to the identification of those diabetes patients at high risk, and serve as a therapeutic target for both primary and secondary prevention.

Overexpression of miR-146a Might Regulate Polarization Transitions of BV-2 Cells Induced by High Glucose and Glucose Fluctuations

Microglia are critical in neuroinflammation. M1/M2 polarization transitions of microglial phenotypes determine the states of neuroinflammation and are regulated by multiple pathways, including miRNAs and other epigenetic regulations. This study investigated the polarization transitions of microglia induced by high glucose and glucose fluctuations, and the role of miR-146a in regulating M1/M2 polarization transitions of microglia. BV-2 cells were cultured with 25 mmol/L glucose, 75 mmol/L glucose, and 25 mmol/L-75 mmol/L glucose fluctuation for 48 h. BV-2 cells overexpressing miR-146a were generated using a lentiviral vector. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure mRNA expression of miR-146a, CD11b, iNOS, Arg-1, IRAK1, TRAF6, and NF-κB. Immunofluorescence was used to measure CD11b expression. Western blot was used to measure protein expression of CD11b, iNOS, and Arg-1. Compared with those in the 25 mmol/L glucose control group, expression of CD11b, iNOS, TNF-α, and IL-6 in the 75 mmol/L glucose or glucose fluctuation groups of cultured BV-2 cells were significantly increased, while Arg-1 and IL-10 was significantly decreased. These effects were reversed by overexpression of miR-146a. Furthermore, expression of IRAK1, TRAF6, and NF-κB was significantly increased in the high glucose and glucose fluctuation groups; this was reduced after miR-146a overexpression. In sum, high glucose and glucose fluctuations induced polarization transitions from M1 to M2 phenotype in BV-2 cells. Overexpression of miR-146a might protect BV-2 cells from high glucose and glucose fluctuation associated with M1/M2 polarization transitions by downregulating the expression of IRAK1, TRAF6, and NF-κB.

Glucose Variability and Coronary Artery Disease

Fasting blood glucose, postprandial blood glucose and glycated haemoglobin are considered three important indicators for diabetes treatment. There is increasing evidence that glucose variability has more detrimental effects on the coronary arteries than does chronic sustained hyperglycaemia. This overview summarises recent findings in the field of glucose variability and its possible relationship with coronary artery disease. Glucose variability may be a marker of increased progression of coronary disease and plaque vulnerability. It might be a potential new therapeutic target for secondary prevention of coronary artery disease. Future studies will focus on the early detection and control of glucose variability to improve the clinical outcomes in patients with coronary artery disease.

Impact of glycemic variability on myocardial infarct size in patients with ST-segment elevation myocardial infarction: quantitative assessment of left ventricular wall motion severity

Glycemic variability (GV) is relevant to impaired myocardial salvage in acute ST-elevation myocardial infarction (STEMI). Severity of hypokinesis at the infarct site as assessed from contrast left ventriculography can reportedly predict infarct size in STEMI. We prospectively studied 58 consecutive patients (mean age, 63 ± 11 years) with anterior or inferior STEMI who underwent successful reperfusion therapy. Mean amplitude of glucose excursion (MAGE) was obtained from continuous glucose monitoring system. Patients were divided into the upper tertile of MAGE as Group H, and the other two-thirds as Group L. Serial regional wall motion severity at the infarct site was computed postprocedure and at follow-up using a quantitative left ventricular analysis system. Impaired myocardial salvage was defined as severity recovery ratio < 20%. Significantly shorter onset-to-balloon time (196.9 vs. 279.0 min, p = 0.033) and relatively lower postprocedural wall motion severity (2.4 vs. 2.9, p = 0.096) were observed in Group H, but absolute severity recovery was significantly smaller in Group H (0.5 vs. 1.3, p = 0.017). Multivariate analysis showed higher MAGE as predictive of impaired myocardial salvage (OR, 406.10; 95% CI, 4.41-37,366.60; p = 0.009). Recovery of reginal wall motion severity at the infarct site was compromised in STEMI patients with higher MAGE. Our results suggest that final infarct size is potentially larger than expected in STEMI patients with higher GV.

Glycemic variability is associated with myocardial damage in nondiabetic patients with ST-elevation myocardial infarction

Background

Glycemic variability (GV) induces coronary microcirculatory disturbance and myocardial damage in diabetic patients with acute myocardial infarction. However, in nondiabetic acute myocardial infarction patients, the relationship between GV and myocardial damage remains unclear.

Patients and methods

We investigated GV with a continuous glucose monitoring system in nondiabetic ST-segment elevation myocardial infarction patients treated with emergent percutaneous coronary intervention. GV was expressed as the mean amplitude of glycemic excursions (MAGE). Myocardial damage was estimated by myocardial blush grade and ST-segment resolution (STRes). STRes was defined as complete (>70%), partial (30–70%), or none (<30%).

Results

Consecutive patients (n=73) were enrolled and classified into a lower or higher MAGE group on the basis of the median MAGE. The higher MAGE group showed lower levels of myocardial blush grade (2.41±0.76 vs. 1.72±0.85, P=0.001) and STRes (complete: 56.8 vs. 33.3%, P=0.044; partial: 32.4 vs. 36.1%, P=0.741; none: 10.8 vs. 30.6%, P=0.037).

Conclusion

GV was associated with myocardial damage after percutaneous coronary intervention in nondiabetic ST-segment elevation myocardial infarction patients.

Prognostic Value of the Acute-to-Chronic Glycemic Ratio at Admission in Acute Myocardial Infarction: A Prospective Study

OBJECTIVE

Acute hyperglycemia is a powerful predictor of poor prognosis in acute myocardial infarction (AMI), particularly in patients without diabetes. This emphasizes the importance of an acute glycemic rise rather than glycemia level at admission alone. We investigated in AMI whether the combined evaluation of acute and chronic glycemic levels, as compared with admission glycemia alone, may have a better prognostic value.

RESEARCH DESIGN AND METHODS

We prospectively measured admission glycemia and estimated average chronic glucose levels (mg/dL) by the following formula: [(28.7 × glycosylated hemoglobin %) - 46.7], and calculated the acute-to-chronic (A/C) glycemic ratio in 1,553 consecutive AMI patients (mean ± SD age 67 ± 13 years). The primary end point was the combination of in-hospital mortality, acute pulmonary edema, and cardiogenic shock.

RESULTS

The primary end point rate increased in parallel with A/C glycemic ratio tertiles (5%, 8%, and 20%, respectively; P for trend <0.0001). A parallel increase was observed in troponin I peak value (15 ± 34 ng/mL, 34 ± 66 ng/mL, and 68 ± 131 ng/mL; P < 0.0001). At multivariable analysis, A/C glycemic ratio remained an independent predictor of the primary end point and of troponin I peak value, even after adjustment for major confounders. At reclassification analyses, A/C glycemic ratio showed the best prognostic power in predicting the primary end point as compared with glycemia at admission in the entire population (net reclassification improvement 12% [95% CI 4-20]; P = 0.003) and, particularly, in patients with diabetes (27% [95% CI 14-40]; P < 0.0001).

CONCLUSIONS

In AMI patients with diabetes, A/C glycemic ratio is a better predictor of in-hospital morbidity and mortality than glycemia at admission.

Impact of CD14++CD16+ monocytes on coronary plaque vulnerability assessed by optical coherence tomography in coronary artery disease patients

BACKGROUND AND AIMS

This study examined the impact of CD14⁺⁺CD16⁺ monocytes on coronary plaque vulnerability, as assessed by optical coherence tomography (OCT), and investigated their association with daily glucose fluctuation. Although increased CD14⁺⁺CD16⁺ monocyte levels have been reported to increase cardiovascular events, their impact on coronary plaque vulnerability in coronary artery disease (CAD) patients with or without diabetes mellitus (DM) remains unclear.

METHODS

This prospective observational study included 50 consecutive patients with CAD, receiving lipid-lowering therapy and undergoing coronary angiography and OCT. Patients were divided into 3 tertiles according to the CD14⁺⁺CD16⁺ monocyte percentages assessed by flow cytometry. Standard OCT parameters were assessed for 97 angiographically intermediate lesions (diameter stenosis: 30-70%). Daily glucose fluctuation was analyzed by measuring the mean amplitude of glycemic excursion (MAGE).

RESULTS

CD14⁺⁺CD16⁺ monocytes negatively correlated with fibrous cap thickness (r = -0.508, p < 0.01). The presence of thin-cap fibroatheroma (TCFA) was increased stepwise according to the tertile of CD14⁺⁺CD16⁺ monocytes (0 [tertile 1] vs. 5 [tertile 2] vs. 10 [tertile 3], p < 0.01). CD14⁺⁺CD16⁺ monocytes were a significant determinant of TCFA (OR 1.279, p = 0.001). In non-DM patients, a significant relationship was found between CD14⁺⁺CD16⁺ monocytes and MAGE (r = 0.477, p = 0.018).

CONCLUSIONS

CD14⁺⁺CD16⁺ monocytes were associated with coronary plaque vulnerability in CAD patients with well-regulated lipid levels both in DM and non-DM patients. Cross-talk between glucose fluctuation and CD14⁺⁺CD16⁺ monocytes may enhance plaque vulnerability, particularly in non-DM patients. CD14⁺⁺CD16⁺ monocytes could be a possible therapeutic target for coronary plaque stabilization.

Impact of CD14++CD16+ monocytes on plaque vulnerability in diabetic and non-diabetic patients with asymptomatic coronary artery disease: a cross-sectional study

Background

Previously, we have reported that daily glucose fluctuations could affect coronary plaque vulnerability, but the underlying mechanisms remained unclear. This study sought to investigate the impact of CD14⁺⁺CD16⁺ monocytes on plaque vulnerability, as assessed by virtual histology intravascular ultrasound (VH-IVUS), as well as their relationship to fluctuating glucose levels in patients with asymptomatic coronary artery disease (CAD).

Methods

Fifty-one patients with asymptomatic CAD, who were undergoing lipid-lowering therapy and underwent VH-IVUS evaluation for angiographically mild to moderate lesions, were enrolled in the study. Standard VH-IVUS parameters, including the percentage volume of the necrotic core (%NC) within the plaque and the presence of a virtual histology thin-cap fibroatheroma (VH-TCFA), were then evaluated. Additionally, monocyte subsets were assessed by flow cytometry, and daily glucose fluctuations were analyzed by measuring the mean amplitude of glycemic excursion (MAGE).

Results

Among 82 plaques from 22 diabetes mellitus (DM) patients and 29 non-DM patients, 15 VH-TCFAs were identified. CD14⁺⁺CD16⁺ monocyte counts significantly correlated with both  %NC and the presence of VH-TCFA (%NC: r = 0.339, p = 0.002; VH-TCFA: p = 0.003). Multivariate logistic regression analysis revealed that CD14⁺⁺CD16⁺ monocyte counts were independently associated with VH-TCFA (odds ratio = 1.029, p = 0.004). Furthermore, CD14⁺⁺CD16⁺ monocyte counts were significantly correlated with the MAGE score in the non-DM patients (r = 0.544, p = 0.005).

Conclusions

CD14⁺⁺CD16⁺ monocyte levels are associated with coronary plaque vulnerability and can serve as a biomarker for VH-TCFA in patients with CAD undergoing lipid-lowering therapy. In patients without DM, glucose fluctuations may alter the balance of monocyte subsets.

Trial registration UMIN Registry number: UMIN000021228

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0577-8) contains supplementary material, which is available to authorized users.

Relationship Between Glucose Fluctuations and ST-Segment Resolution in Patients With ST-Elevation Acute Myocardial Infarction

This study was conducted to assess whether any relationships exist between glucose fluctuations and electrocardiographic surrogate markers of reperfusion injury in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).We prospectively studied 63 consecutive patients with STEMI undergoing primary PCI. Patients had either diabetes (n = 30), impaired glucose tolerance (n = 26), impaired fasting glucose (n = 1), or normal glucose tolerance (n = 6). STsegment resolution (STR, %) was measured using electrocardiograms recorded 60 minutes after PCI. STR was categorized as ≥ 30% and < 30%. Glucose fluctuations were assessed by the following parameters obtained from a continuous glucose monitoring system: mean amplitude of glucose excursion (MAGE, mg/dL); and area under curve with reference to mean blood glucose (AUC_MBG, mg/ dL/day).Both MAGE and AUC_MBG were significantly higher in STR < 30%. In univariate analysis, MAGE ≥ 70 mg/dL (OR = 17.0; 95%CI, 1.93-150.12; P < 0.01), AUC_MBG ≥ 20 mg/dL/day (OR = 10.9; 95%CI, 1.92-61.77; P < 0.01), and reperfusion arrhythmias (OR = 7.6; 95%CI, 1.32-44.29; P < 0.05) were significantly associated with suboptimal STR. Multiple logistic regression analysis showed only MAGE ≥ 70 mg/dL was predictive of suboptimal STR (OR = 22.5; 95%CI, 2.43-208.66, P < 0.01).Parameters of glucose fluctuations correlated with electrocardiographic surrogate markers of impaired myocardial salvage in STEMI after reperfusion therapy. Our results suggest that glucose fluctuations may represent a potential therapeutic target to reduce myocardial reperfusion injury in STEMI.

Effects of the Mean Amplitude of Glycemic Excursions and Vascular Endothelial Dysfunction on Cardiovascular Events in Nondiabetic Patients With Coronary Artery Disease

Background

Mean amplitude of glycemic excursion (MAGE) is commonly used to gauge the degree of glucose level fluctuations. MAGE plays a significant role in vascular endothelial dysfunction and cardiovascular events in patients with diabetes mellitus (DM), but its significance is not clear in non‐DM patients. Thus, we examined the impact of MAGE and vascular endothelial dysfunction on clinical outcomes in non‐DM patients with coronary artery disease.

Methods and Results

We followed non‐DM patients (n=65) for 12 months who underwent percutaneous coronary intervention and assessed the relationship among MAGE, reactive hyperemia index (RHI) measured by reactive hyperemia peripheral arterial tonometry as endothelial function, and cardiovascular events. Cardiovascular events analyzed were cardiovascular death, myocardial infarction, unstable angina, and revascularizations. Compared with patients with MAGE <65 mg/dL (normal glycemic excursions), the group with MAGE ≥65 mg/dL (high glycemic excursions) had significantly higher high‐sensitivity C‐reactive protein (0.10±0.11 mg/dL versus 0.18±0.13 mg/dL, P=0.006) and lower RHI (0.64±0.21 versus 0.51±0.22, P=0.035). The multivariable analysis identified high MAGE and low RHI (≤0.56) as risk factors associated with cardiovascular events (hazard ratio, 5.6; 95% RI, 1.72–18.4 [P=0.004] versus hazard ratio, 4.5; 95% RI, 1.37–14.9 [P=0.013]). When the prognosis was classified by combination with MAGE and RHI, the incidence of cardiovascular events was 46.7% (high MAGE+low RHI), 26.7% (high MAGE+high RHI), 20.0% (low MAGE+low RHI), and 6.6% (low MAGE+high RHI) in descending order (P=0.014). Receiver operating characteristic curve analysis revealed that MAGE, RHI, and MAGE+RHI were each associated with cardiovascular events (area under the curve 0.780, 0.727, and 0.796, respectively).

Conclusions

MAGE was associated with cardiovascular events in non‐DM patients with coronary artery disease. Furthermore, the combination with MAGE and RHI was useful for further subdivision of the risk of cardiovascular events.

Glucose time series complexity as a predictor of type 2 diabetes

BACKGROUND

Complexity analysis of glucose profile may provide valuable information about the gluco-regulatory system. We hypothesized that a complexity metric (detrended fluctuation analysis, DFA) may have a prognostic value for the development of type 2 diabetes in patients at risk.

METHODS

A total of 206 patients with any of the following risk factors (1) essential hypertension, (2) obesity or (3) a first-degree relative with a diagnosis of diabetes were included in a survival analysis study for a diagnosis of new onset type 2 diabetes. At inclusion, a glucometry by means of a Continuous Glucose Monitoring System was performed, and DFA was calculated for a 24-h glucose time series. Patients were then followed up every 6 months, controlling for the development of diabetes.

RESULTS

In a median follow-up of 18 months, there were 18 new cases of diabetes (58.5 cases/1000 patient-years). DFA was a significant predictor for the development of diabetes, with ten events in the highest quartile versus one in the lowest (log-rank test chi2 = 9, df = 1, p = 0.003), even after adjusting for other relevant clinical and biochemical variables. In a Cox model, the risk of diabetes development increased 2.8 times for every 0.1 DFA units. In a multivariate analysis, only fasting glucose, HbA_1c and DFA emerged as significant factors.

CONCLUSIONS

Detrended fluctuation analysis significantly performed as a harbinger of type 2 diabetes development in a high-risk population. Complexity analysis may help in targeting patients who could be candidates for intensified treatment. Copyright © 2016 The Authors. Diabetes/Metabolism Research and Reviews Published by John Wiley & Sons Ltd.

Effects of sitagliptin as initial therapy in newly diagnosed elderly type 2 diabetics: A randomized controlled study

The objective of this study was to investigate the characteristics of blood glycemic excursion, incretins and pancreatic hormone secretion in elderly people with newly diagnosed type 2 diabetes mellitus (T2DM) and to study the effects of sitagliptin on glycemic excursion in these subjects. A total of 129 newly diagnosed T2DM patients were enrolled in the study from March 2012 to August 2013. Clinical data, serum incretin, pancreatic hormone and continuous glucose monitoring data were collected. Among these subjects, elderly patients (NEDM) randomly received metformin combined with sitagliptin phosphate or glimepiride for 24 weeks. The blood glucose, glycosylated hemoglobin A_1c (GHbA_1c), serum incretins and pancreatic hormone levels were determined. During the oral glucose tolerance test (OGTT), 30 min insulin and C-peptide levels, 120 min insulin levels and ratio of the increases of insulin and blood glucose levels after 30 min of sugar loading (∆Ins30/∆Glu30) were significantly lower in elderly patients than in middle-aged patients (P<0.05). In addition, the glucagon elevation at 30 min was higher and the glucagon-like peptide-1 (GLP-1) at 30 min was lower in the elderly patients (P<0.05). Glucose excursion indices, including the standard deviation of the average blood glucose, intraday mean average glucose excursions (MAGE), and mean of daily differences (MODD), were significantly higher in the elderly patients (P<0.05). During the OGTT, insulin, C-peptide and ∆Ins30/∆Glu30 results at 30 min and GLP-1 levels at 120 min in NEDM subjects were significantly increased (P<0.05) and glucagon levels at 30 min was significantly lower after sitagliptin treatment (P<0.05) compared with glimepiride. Moreover, MAGE and MODD were significantly lower in the sitagliptin group after treatment compared to those in the glimepiride group (P<0.05). No severe hypoglycemia or cardiovascular diseases were observed. Strong blood glucose excursions occur in elderly patients with newly diagnosed T2DM. Sitagliptin phosphate combined with metformin effectively and safely improves glycemic excursion and carbohydrate metabolism in NEDM patients by promoting the first phase of insulin and incretin secretion and inhibiting glucagon secretion of.

Glycemic Variability on Continuous Glucose Monitoring System Correlates With Non-Culprit Vessel Coronary Plaque Vulnerability in Patients With First-Episode Acute Coronary Syndrome - Optical Coherence Tomography Study

BACKGROUND

Glycemic variability (GV) is associated with coronary plaque rupture at the culprit lesion in acute myocardial infarction (AMI). The present study determined the relationship between GV and coronary plaque vulnerability in the non-culprit vessel.

METHODS AND RESULTS

The present prospective study involved 46 patients with first-episode acute coronary syndrome (ACS) who underwent optical coherence tomography in the non-culprit vessel. The relationship between GV, assessed with continuous glucose monitoring system, and the presence of thin-cap fibroatheroma (TCFA) at the non-culprit plaque with mild-to-moderate stenosis in the non-culprit vessel, was assessed. GV was quantified using mean amplitude of glycemic excursion (MAGE). Patients were divided into tertiles according to MAGE. TCFA was observed in 13 (28%) of the 46 patients. Fibrous cap thickness was thinner (MAGE tertiles: high, 80±40 µm; intermediate, 152±122 µm; low, 155±102 µm; P=0.01), and TCFA was more common (MAGE tertiles: high, 50%; intermediate, 27%; low, 7%; P=0.03) in patients with high MAGE. On multivariate logistic analysis high MAGE was the only significant determinant of TCFA, independent of coronary risk factors (OR, 5.000; P=0.021), homeostasis model assessment of insulin resistance, and hemoglobin A1c(OR, 5.674; P=0.018).

CONCLUSIONS

High MAGE measured early after the onset of first-episode ACS correlated with thinner fibrous cap thickness and higher prevalence of TCFA at the non-culprit plaque in the non-culprit vessel.

Glycemic Variability on Continuous Glucose Monitoring System Predicts Rapid Progression of Non-Culprit Lesions in Patients With Acute Coronary Syndrome

BACKGROUND

Although rapid progression (RP) of coronary artery disease (CAD) has been shown to be a powerful predictor of cardiovascular events, predictors of RP are not fully understood in patients with acute coronary syndrome (ACS).

METHODS AND RESULTS

We prospectively investigated the clinical impact of glycemic variability (GV), as determined on continuous glucose monitoring system (CGMS), on RP of non-culprit lesions in 88 patients with ACS. RP was defined as ≥10% diameter reduction in a pre-existing stenosis ≥50%; ≥30% diameter reduction in a stenosis <50%; development of a new stenosis ≥30% in a previously normal segment; or progression of any stenosis to total occlusion. Patients were classified into 2 groups according to the presence (progressor, n=20) or absence (non-progressor, n=68) of RP. All patients were equipped with a CGMS during the stable phase, and mean amplitude of glycemic excursion (MAGE) was calculated as a marker of GV. Mean MAGE was significantly higher in progressors than in non-progressors (55±19 mg/dl vs. 37±18 mg/dl, P<0.01). On multiple logistic regression analysis, MAGE was an independent predictor of RP (odds ratio, 1.06 per 1 mg/dl; P<0.01).

CONCLUSIONS

MAGE early after the onset of ACS is a predictor of RP of non-culprit lesions.

Glycosylated hemoglobin and the risk of periprocedural myocardial infarction in non-diabetic patients

BACKGROUND

Alterations of glucose homeostasis have been reported to occur even in non-diabetic patients, thus increasing the risk of cardiovascular events and worsening the outcome after an acute myocardial infarction (AMI). Still debated is the role of impaired glucose control in patients undergoing percutaneous coronary intervention (PCI), as hyperglycemia, represents an important pro-thrombotic stimulus, increasing platelet reactivity and potentially procedural complications. Therefore, the aim of our study was to assess the association between glycosylated hemoglobin and periprocedural myocardial infarction (PMI) in non-diabetic patients undergoing PCI.

METHODS

We included patients without history of diabetes undergoing elective PCI. PMI was defined as creatine kinase-MB increase by 3 times the upper limit normal or by 50% of an elevated baseline value, whereas periprocedural myonecrosis as Troponin I increase by 3× ULN or 50% of baseline.

RESULTS

Our population is represented by 1199 patients, who were divided according to tertile values of glycosylated hemoglobin (HbA1c). Higher HbA1c was associated with ageing (p<0.001), hypertension (p=0.005), previous myocardial infarction (p=0.009), PCI (p<0.001) or CABG (p=0.001), treatment with diuretics (p<0.001), higher levels of glycemia (p<0.001) and white blood cells (p=0.02), multivessel coronary artery disease (p=0.03), higher rate of instent restenosis (p=0.02). HbA1c did not impact on periprocedural myocardial infarction (p=0.85; adjusted OR [95% CI]=0.91 [0.74-1.12], p=0.38) or myonecrosis (p=0.69; adjusted OR [95% CI]=0.95 [0.80-1.13], p=0.56). Similar results were obtained fasting glycemia for PMI (p=0.82, adjusted OR [95% CI]=0.90 [0.71-1.14], p=0.37) and myonecrosis (p=0.21, adjusted OR [95% CI]=1.02 [0.84-1.24], p=0.84) and confirmed in high-risk subsets of patients.

CONCLUSIONS

In non-diabetic patients undergoing elective PCI, neither glycosylated hemoglobin levels nor fasting glycemia are associated with the risk of periprocedural myocardial infarction and necrosis.

Glycemic Variability Determined by Continuous Glucose Monitoring System Predicts Left Ventricular Remodeling in Patients With a First ST-Segment Elevation Myocardial Infarction

BACKGROUND

Impaired glucose metabolism plays an important role in patients with acute myocardial infarction, but the clinical significance of glycemic variability (GV) early after the onset of ST-segment elevation myocardial infarction (STEMI) remains to be fully elucidated.

METHODS AND RESULTS

We prospectively investigated the clinical impact of GV, as determined by a continuous glucose monitoring system (CGMS), on left ventricular remodeling (LVR) assessed by cardiac magnetic resonance imaging (CMR) in 69 patients (63±13 years, 59 men) with a first reperfused STEMI within 12 h of onset. All patients were equipped with a CGMS when in a stable phase after admission and underwent repeat CMR at baseline and 7 months follow-up. Patients were divided into 2 groups according to the mean amplitude of glycemic excursions (MAGE). Patients in the upper tertile of MAGE were categorized as group High (H) and the other two-thirds as group Low (L). LVR was defined as an absolute increase in left ventricular end-diastolic volume index of ≥20%. LVR more frequently occurred in group H than in group L (56% vs. 11%, P<0.001). Multivariate analysis showed the higher MAGE group was an independent predictor of LVR in the chronic phase (odds ratio, 13.999; 95% confidence interval, 3.059 to 64.056; P=0.001).

CONCLUSIONS

MAGE early after the onset of STEMI identified patients with LVR in the chronic phase.

Effect of intraoperative glucose fluctuation and postoperative IL-6, TNF-α, CRP levels on the short-term prognosis of patients with intracranial supratentorial neoplasms

OBJECTIVE

To investigate the effect of intraoperative glucose fluctuation and postoperative interlukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP) levels on the short-term prognosis of patients with intracranial supratentorial neoplasms.

MATERIALS AND METHODS

Eighty-six patients undergoing intracranial excision were selected in The Second Hospital of Jilin University. According to the condition of glucose fluctuation, the patients were divided into group A (glucose fluctuation <2.2 mmol/L, n=57) and group B (glucose fluctuation ≥2.2 mmol/L, n=29). Glucose was assessed by drawing 2 mL blood from internal jugular vein in two groups in the following time points, namely fasting blood glucose 1 d before operation (T0), 5 min after anesthesia induction (T1), intraoperative peak glucose (T2), intraoperative lowest glucose (T3), 5 min after closing the skull (T4), immediately after returning to intensive care unit (ICU) (T5) and 2 h after returning to ICU (T6). 1 d before operation and 1, 3 and 6 d after operation, serum IL-6 and TNF-α levels were detected with enzyme-linked immunosorbent assay (ELISA), and CRP level with immunoturbidimetry. Additionally, postoperative adverse reactions were monitored.

RESULTS

There was no statistical significance between two groups regarding the operation time, anesthesia time, amount of intraoperative bleeding and blood transfusion (P>0.05). The glucose levels in both groups at T1~T6 went up conspicuously compared with that at T0 (P<0.01), and those in group B at T2, T4, T5 and T6 were significantly higher than in group A (P<0.01). Serum IL-6, TNF-α and CRP levels in both groups 1, 3 and 6 d after operation increased markedly compared with 1 d before operation (P<0.01), but the increased range in group A was notably lower than in group B (P<0.05 or P<0.01). Postoperative incidences of hypoglycemia, hyperglycemia and myocardial ischemia in group A were significantly lower than in group B (P<0.05), and respiratory support time obviously shorter than in group B (P<0.01).

CONCLUSIONS

The glucose fluctuation of patients undergoing intracranial excision is related to postoperative IL-6, TNF-α and CRP levels and those with small range of glucose fluctuation have better prognosis.

Impact of acute and chronic hyperglycemia on in-hospital outcomes of patients with acute myocardial infarction

This study was undertaken to assess the impact of acute hyperglycemia (acute-HG) and chronic hyperglycemia (chronic-HG) on short-term outcomes in patients with acute myocardial infarction (AMI). This study consisted of 696 patients with AMI. Acute-HG was defined as admission plasma glucose ≥200 mg/dl and chronic-HG as hemoglobin A1c ≥6.5%. Acute-HG was associated with higher peak serum creatine kinase (4,094 ± 4,594 vs 2,526 ± 2,227 IU/L, p <0.001) and in-hospital mortality (9.8% vs 1.6%, p <0.001). On the contrary, there was no significant difference in peak creatine kinase (2,803 ± 2,661 vs 2,940 ± 3,181 IU/L, p = 0.59) and mortality (3.3 vs 3.7%, p = 0.79) between patients with chronic-HG and those without. Multivariate analysis showed that admission plasma glucose was an independent predictor of in-hospital mortality (odds ratio 1.15, 95% confidence interval 1.05 to 1.27, p <0.001), but hemoglobin A1c was not. When only patients with acute-HG were analyzed, chronic-HG was associated with a significantly smaller infarct size (3,221 ± 3,001 vs 5,904 ± 6,473 IU/L, p <0.001) and lower in-hospital mortality (5.5 vs 18.9%, p = 0.01). In conclusion, these results suggested that acute-HG, but not chronic-HG, was associated with adverse short-term outcomes after AMI. Paradoxically, in patients with acute-HG, chronic-HG might abate the adverse effects of acute-HG.

Glucose series complexity in hypertensive patients

Nonlinear methods have been applied to the analysis of biological signals. Complexity analysis of glucose time series may be a useful tool for the study of the initial phases of glucoregulatory dysfunction. This observational, cross-sectional study was performed in patients with essential hypertension. Glucose complexity was measured with detrended fluctuation analysis (DFA), and glucose variability was measured by the mean amplitudes of glycemic excursion (MAGE). We included 91 patients with a mean age of 59 ± 10 years. We found significant correlations for the number of metabolic syndrome (MS)-defining criteria with DFA (r = 0.233, P = .026) and MAGE (r = 0.396, P < .0001). DFA differed significantly between patients who complied with MS and those who did not (1.44 vs. 1.39, P = .018). The MAGE (f = 5.3, P = .006), diastolic blood pressures (f = 4.1, P = .018), and homeostasis model assessment indices (f = 4.2, P = .018) differed between the DFA tertiles. Multivariate analysis revealed that the only independent determinants of the DFA values were MAGE (β coefficient = 0.002, 95% confidence interval: 0.001-0.004, P = .001) and abdominal circumference (β coefficient = 0.002, 95% confidence interval: 0.000015-0.004, P = .048). In our population, DFA was associated with MS and a number of MS criteria. Complexity analysis seemed to be capable of detecting differences in variables that are arguably related to the risk of the development of type 2 diabetes.