Diabetes mellitus and acute coronary syndrome: lessons from randomized clinical trials

Diabetes Mellitus in Acute Coronary Syndrome

The global prevalence of diabetes mellitus (DM) has led to a pandemic, with significant microvascular and macrovascular complications including coronary artery disease (CAD), which worsen clinical outcomes and cardiovascular prognosis. Patients with both acute coronary syndrome (ACS) and DM have worse prognosis and several pathophysiologic mechanisms have been implicated including, insulin resistance, hyperglycemia, endothelial dysfunction, platelet activation and aggregations as well as plaque characteristics and extent of coronary lesions. Therefore, regarding reperfusion strategies in the more complex anatomies coronary artery bypass surgery may be the preferred therapeutic strategy over percutaneous coronary intervention while both hyperglycemia and hypoglycemia should be avoided with closed monitoring of glycemic status during the acute phase of myocardial infraction. However, the best treatment strategy remains undefined. Non-insulin therapies, due to the low risk of hypoglycemia concurrently with the multifactorial CV protective effects, may be proved to be the best treatment option in the future. Nevertheless, evidence for the beneficial effects of glucagon like peptide-1 receptor agonists, dipeptidyl-peptidase 4 inhibitors and sodium glycose cotransporter 2 inhibitors, despite accumulating, is not robust and future randomized control trials may provide more definitive data.

Association between admission-blood-glucose-to-albumin ratio and clinical outcomes in patients with ST-elevation myocardial infarction undergoing percutaneous coronary intervention

Introduction

It is unclear whether admission-blood-glucose-to-albumin ratio (AAR) predicts adverse clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) who are treated with percutaneous coronary intervention (PCI). Here, we performed a observational study to explore the predictive value of AAR on clinical outcomes.

Methods

Patients diagnosed with STEMI who underwent PCI between January 2010 and February 2020 were enrolled in the study. The patients were classified into three groups according to AAR tertile. The primary outcome was in-hospital all-cause mortality, and the secondary outcomes were in-hospital major adverse cardiac events (MACEs), as well as all-cause mortality and MACEs during follow-up. Logistic regression, Kaplan-Meier analysis, and Cox proportional hazard regression were the primary analyses used to estimate outcomes.

Results

Among the 3,224 enrolled patients, there were 130 cases of in-hospital all-cause mortality (3.9%) and 181 patients (5.4%) experienced MACEs. After adjustment for covariates, multivariate analysis demonstrated that an increase in AAR was associated with an increased risk of in-hospital all-cause mortality [adjusted odds ratio (OR): 2.72, 95% CI: 1.47-5.03, P = 0.001] and MACEs (adjusted OR: 1.91, 95% CI: 1.18-3.10, P = 0.009), as well as long-term all-cause mortality [adjusted hazard ratio (HR): 1.64, 95% CI: 1.19-2.28, P = 0.003] and MACEs (adjusted HR: 1.58, 95% CI: 1.16-2.14, P = 0.003). Receiver operating characteristic (ROC) curve analysis indicated that AAR was an accurate predictor of in-hospital all-cause mortality (AUC = 0.718, 95% CI: 0.675-0.761) and MACEs (AUC = 0.672, 95% CI: 0.631-0.712).

Discussion

AAR is a novel and convenient independent predictor of all-cause mortality and MACEs, both in-hospital and long-term, for STEMI patients receiving PCI.

Short Versus Long Duration of Dual Antiplatelet Therapy After Second-Generation Drug-Eluting Stents Implantation in Patients with Diabetes

BACKGROUND

Duration of dual antiplatelet therapy (DAPT) in patients undergoing percutaneous coronary intervention (PCI) remains uncertain, with increasing data suggestive of acceptable short-term duration. Metabolically accelerated atherosclerosis associated with diabetes makes it essential to study short-term DAPT in this subgroup. With limited studies determining optimal DAPT strategies after second-generation stents in this subset, we aimed to establish the optimal duration of DAPT in the diabetic population using second-generation stents.

QUESTION

To determine optimal DAPT duration in diabetic population undergoing PCI in 2nd generation stents.

DATA SOURCES

We conducted an electronic database search of randomized controlled trials from PubMed/Medline, Embase, Cochrane, and Web of Science databases.

STUDY DESIGN

A meta-analysis was conducted comparing outcomes of short-term (3-6 months) DAPT therapy versus long-term (12 months) DAPT therapy in the diabetic population undergoing PCI with second-generation stents.

RESULTS

A total of 5 randomized controlled trials were included with a total of 3117 diabetic patients. Short-term DAPT did not show any statistical difference from long-term DAPT in achieving primary outcomes (relative ratio: 0.96, 95% confidence interval (CI) 0.68-1.35, P = 0.84). Overall mortality (OR 0.92; 95% CI, 0.52-1.63, P = 0.98), myocardial infarction [odds ratio (OR)OR 1.02; 95% CI, 0.53-1.94, P = 0.85], stent thrombosis (OR 1.20; 95% CI, 0.55-2.60, P = 0.55), target vessel revascularization (OR 1.10; 95% CI, 0.45-2.73, P = 0.74), and stroke (OR 0.50; 95% CI, 0.082-2.43, P = 0.81) did not show any statistical difference between the 2 groups. Similarly, a subgroup analysis of study population comparing 6 versus 12 months of DAPT in diabetic population did not show any difference in net primary outcomes (relative ratio: 0.86, 95% CI 0.45-1.45, P = 0.60). There was no significant heterogeneity noted between the 2 groups.

CONCLUSION

This meta-analysis showed no statistically significant benefit of longer DAPT over shorter DAPT therapy in patients undergoing PCI with drug-eluting stent in patients with diabetes.

Triglyceride glucose index predicts all-cause mortality in oldest-old patients with acute coronary syndrome and diabetes mellitus

BACKGROUND

Acute coronary syndrome (ACS) and diabetes mellitus (DM) are the leading health risks for the elderly. Triglyceride-glucose (TyG) index is a novel and reliable indicator of insulin resistance (IR). This study aims to explore the relationship between the TyG index and all-cause mortality in oldest-old patients with ACS and DM.

METHODS

Seven hundred twenty hospitalized patients with ACS aged ≥ 80 years were enrolled, and 699 patients signed informed consent for the study. During the follow-up period, 37 were lost to follow-up, and the follow-up rate was 94.7%. 231 ACS patients with DM were selected for the study's analyses. Kaplan-Meier curve, Cox regression model and receiver operating characteristic (ROC) curve were used to analyze the association between the TyG index and all-cause mortality.

RESULTS

The mean age of participants was 81.58 ± 1.93 years, and 32.47% were women. Compared to TyG tertile 1, the Hazard Ratio (HR) [95% confidence interval (CI)] of all-cause mortality was 2.04 (1.09, 3.81) for TyG tertile 3 in the fully adjusted model. For the TyG index per standard deviation (SD) increment, the HR (95% CI) of all-cause mortality was 1.44 (1.13, 1.83). Further, the association between the TyG index and all-cause mortality was dose-response (P for trend = 0.026). ROC curve analyses indicated that the TyG index outperformed FBG and TG in the prediction of mortality risk and improved the prognostic value of the Gensini score combined with LVEF.

CONCLUSION

The TyG index predicts the risk of all-cause mortality in the oldest-old ACS patients with DM.

Relation of Red Cell Distribution Width to Glucose Metabolism and Adverse Long-Term Prognosis in Patients with Acute Coronary Syndrome

INTRODUCTION

Red cell distribution width (RDW) reflects the heterogeneity of red blood cell size. However, few studies examined whether RDW is related to glucose metabolism indices, such as fasting blood glucose (FBG) and hemoglobin A1c (HbA1c), diabetic mellitus (DM) state or long-term outcomes of acute coronary syndrome (ACS) patients.

METHODS AND RESULTS

A total of 448 consecutive patients with ACS were enrolled in this study. All patients were followed up for major cardiovascular adverse events (MACEs), and the mean follow-up was 952 days. Linear regression analysis showed that RDW inversely correlated with FBG but not HbA1c or DM. Kaplan-Meier survival curve analysis demonstrated that higher RDW levels were significantly positively associated with MACEs in the whole study population and the ACS patients with high FBG but not the low FBG group. Cox multivariate regression analysis revealed the independent function of RDW on MACEs in all ACS patients and ACS patients with high FBG. The receiver operating characteristic (ROC) curve demonstrated the optimal cutoff value of RDW for MACEs.

CONCLUSION

We first reported that higher RDW was associated with decreased FBG but not HbA1c or DM and an increased risk of MACEs in patients with ACS. This relationship was also found in ACS patients with higher FBG levels but not in ACS patients with lower FBG.

The Risk Factors of Acute Coronary Syndrome in Young Women: A Systematic Review and Meta-Analysis

BACKGROUND

Acute coronary syndrome (ACS) has been one of the leading causes of mortality in the world. Despite common understanding regarding ACS as an older population's or man's disease, the number of young women affected by this condition is increasing. Many studies have assessed the risk factors of ACS, but only a few studies focused on this subpopulation. Therefore, this systematic review and meta-analysis aim to evaluate the risk factors predisposing to ACS in the young women population.

METHODS

Nine online databases were screened from the date of inception to September 2021, where the acquired studies were evaluated using the PRISMA statement. The inclusion criteria were a case control study with women age cut-off of <50 years. The risk factors of acute coronary syndrome were analyzed using a random-effect model, expressed as summary statistics of odds ratio (OR) for categorical variable and standard mean difference (SMD) for continuous data with normal distribution, with 95% confidence interval (CI). Quality assessment was conducted using the STROBE statement.

RESULTS

Seven studies with the total of 7042 patients met the inclusion criteria of this metaanalysis. Diabetes mellitus, high BMI, obesity, hypercholestrolemia, hypertension, smoking, and family history significantly increased acute coronary syndrome risk in young women. Other risks such as heavy alcohol consumption, oral contraceptive use, and postmenopausal state were associated with higher risk of ACS.

CONCLUSION

The independent risk factors which are strongly related to ACS in young women were diabetes mellitus, hypertension, and hypercholesterolemia with odd ratios of 6.21, 5.32, and 4.07. Other risk factors which may be associated with an increased risk of ACS in young women were heavy alcohol consumption, oral contraceptive use, and postmenopausal state. Health promotion and effective intervention on this specific population regarding these risk factors can decrease young female cardiovascular morbidity and mortality as well as improved quality of life of women.

Clinical implications of diabetes mellitus in patients with acute coronary syndrome: Prognostic role and use of new P2Y12 receptor inhibitors

AIMS

We investigated the impact of diabetes mellitus (DM) in acute coronary syndrome (ACS) patients, and the 2-year prognosis based on antiplatelet therapy.

METHODS

This is a prospective and multicenter registry including hospitalized ACS patients. Clinical management and antiplatelet therapy at discharge were recorded. Bleeding events, all-cause mortality and major adverse cardiovascular events (MACEs) were recorded during 2-years and compared according to DM and the P2Y₁₂ receptor inhibitor.

RESULTS

From 1717 ACS patients, 653 (38%) had DM. Diabetic patients were older, more commonly females, with higher prevalence of comorbidities and more conservative management. After excluding antiplatelet monotherapy or oral anticoagulation, clopidogrel was prescribed in 59.6% of DM patients. Cox regression analysis showed that DM was an independent risk factor for MACE (aHR 1.39, 95% CI 1.05-1.83). The use of clopidogrel instead of ticagrelor/prasugrel was also independently associated with MACE (aHR 1.71, 95% CI 1.11-2.63), and all-cause mortality (aHR 2.47, 95% CI 1.23-4.96) in diabetic patients (log-rank p-values < 0.001).

CONCLUSIONS

In ACS patients, DM was associated with higher risk of MACE. In such patients, the use of ticagrelor/prasugrel reduced MACE and mortality compared to clopidogrel. Novel P2Y₁₂ receptor inhibitors might be used as the first therapeutic choice in these high-risk patients.

Evaluation of the prognostic ability of serum uric acid for elderly acute coronary syndrome patients with diabetes mellitus: a prospective cohort study

OBJECTIVES

This study evaluated the prognostic power of serum uric acid (UA) in predicting adverse events in elderly acute coronary syndrome (ACS) patients with diabetes mellitus (DM).

METHODS

The analysis involved 718 ACS patients ‍>80 years old whose general clinical data and baseline blood biochemical indicators were collected prospectively from January 2006 to December 2012. These patients were classified into two groups based on DM status, and then followed up after discharge. The Kaplan-Meier method was used for major adverse cardiac event (MACE) rates and all-cause mortality. Multivariate Cox regression was performed to analyze the relationship between UA level and long-term clinical prognosis. Receiver operating characteristic (ROC) curves were analyzed to predict the cutoff value of UA in elderly ACS patients with DM. There were 242 and 476 patients in the DM and non-DM (NDM) groups, respectively, and the follow-up time after discharge was 40‒120 months (median, 63 months; interquartile range, 51‒74 months).

RESULTS

The all-cause mortality, cardiac mortality, and MACE rates in both DM and NDM patients were higher than those in the control group (P=0.001). All-cause mortalities, cardiac mortalities, and MACE rates in DM patients with moderate and high UA levels were significantly higher than those in the NDM group (P=0.001). Long-term survival rates decreased significantly with increased UA levels in the ACS groups (P=0.001). UA (odds ratio (OR)=2.106, 95% confidence interval (CI)=1.244‒3.568, P=0.006) was found to be an independent risk factor for all-cause mortality and MACE in elderly ACS patients with DM. The cutoff value of UA was 353.6 μmol/L (sensitivity, 67.4%; specificity, 65.7%).

CONCLUSIONS

Serum UA level is a strong independent predictor of long-term all-cause death and MACE in elderly ACS patients with DM.

Clinical Outcome between Ticagrelor versus Clopidogrel in Patients with Acute Coronary Syndrome and Diabetes

BACKGROUND

The increased thrombotic risk in patients with acute coronary syndrome (ACS) and diabetes highlights the need for adequate antithrombotic protection. We aimed to compare the 6-month clinical outcomes between ticagrelor and clopidogrel in patients with ACS and diabetes.

METHODS AND RESULTS

The study was a single-center, prospective, randomized, open-label, blinded endpoint, and controlled registry trial. A total of 270 ACS patients with diabetes were randomly assigned in a 1 : 1 ratio to either the ticagrelor group or the clopidogrel group. Follow-up was performed for 6 months, and the data on efficacy outcomes and bleeding events were collected. At 6 months, complete follow-up data were available for 266 (98.5%) of 270 patients, and 4 were lost to follow-up. There was no significant difference in the survival rate of the effective endpoints between the ticagrelor group (n = 133) and the clopidogrel group (n = 133) (HR 0.83, 95% CI 0.44-1.56, p = 0.561), but the incidence of bleeding events in the ticagrelor group was higher than that in the clopidogrel group (HR 1.76, 95% CI 1.00-3.10, p = 0.049).

CONCLUSION

Ticagrelor did not improve the composite of nonfatal MI, target vessel revascularization, rehospitalization, stroke, and death from any cause; however, it significantly increased the incidence of bleeding events defined by the Bleeding Academic Research Consortium (BARC) criteria in Chinese patients with ACS and diabetes during the 6-month follow-up compared with clopidogrel.

Ranolazine Improves Glycemic Variability and Endothelial Function in Patients with Diabetes and Chronic Coronary Syndromes: Results from an Experimental Study

BACKGROUND

Ranolazine is a second-line drug for the management of chronic coronary syndromes (CCS). Glucose-lowering and endothelial effects have also been reported with this agent. However, whether ranolazine may improve short-term glycemic variability (GV), strictly related to the prognosis of patients with type 2 diabetes (T2D), is unknown. Thus, we aimed to explore the effects of adding ranolazine to standard anti-ischemic and glucose-lowering therapy on long- and short-term GV as well as on endothelial function and oxidative stress in patients with T2D and CCS.

METHODS

Patients starting ranolazine (n = 16) were evaluated for short-term GV, haemoglobin 1Ac (Hb1Ac) levels, endothelial-dependent flow-mediated vasodilation (FMD), and oxidative stress levels at enrolment and after 3-month follow-up. The same measurements were collected from 16 patients with CCS and T2D that did not receive ranolazine, matched for age, gender, and body mass index.

RESULTS

A significant decline in Hb1Ac levels was reported after 3-month ranolazine treatment (mean change -0.60%; 2-way ANOVA p = 0.025). Moreover, among patients receiving ranolazine, short-term GV indexes were significantly improved over time compared with baseline (p = 0.001 for time in range; 2-way ANOVA p = 0.010). Conversely, no significant changes were reported in patients without ranolazine. Finally, greater FMD and lower oxidative stress levels were observed in patients on ranolazine at 3 months.

CONCLUSIONS

Ranolazine added to standard anti-ischemic and glucose-lowering therapy demonstrated benefit in improving the glycemic status of patients with T2D and CCS. How this improvement contributes to the overall myocardial benefit of ranolazine requires further studies.

Dalcetrapib Reduces Risk of New-Onset Diabetes in Patients With Coronary Heart Disease

OBJECTIVE

Incident type 2 diabetes is common among patients with recent acute coronary syndrome and is associated with an adverse prognosis. Some data suggest that cholesteryl ester transfer protein (CETP) inhibitors reduce incident type 2 diabetes. We compared the effect of treatment with the CETP inhibitor dalcetrapib or placebo on incident diabetes in patients with recent acute coronary syndrome.

RESEARCH DESIGN AND METHODS

In the dal-OUTCOMES trial, 15,871 patients were randomly assigned to treatment with dalcetrapib 600 mg daily or placebo, beginning 4-12 weeks after an acute coronary syndrome. Absence of diabetes at baseline was based on medical history, no use of antihyperglycemic medication, and hemoglobin A_1c and serum glucose levels below diagnostic thresholds. Among these patients, incident diabetes after randomization was defined by any diabetes-related adverse event, new use of antihyperglycemic medication, hemoglobin A_1c ≥6.5%, or a combination of at least two measurements of serum glucose ≥7.0 mmol/L (fasting) or ≥11.1 mmol/L (random).

RESULTS

At baseline, 10,645 patients (67% of the trial cohort) did not have diabetes. During a median follow-up of 30 months, incident diabetes was identified in 403 of 5,326 patients (7.6%) assigned to dalcetrapib and in 516 of 5,319 (9.7%) assigned to placebo, corresponding to absolute risk reduction of 2.1%, hazard ratio of 0.77 (95% CI 0.68-0.88; P < 0.001), and a need to treat 40 patients for 3 years to prevent 1 incident case of diabetes. Considering only those with prediabetes at baseline, the number needed to treat for 3 years to prevent 1 incident case of diabetes was 25. Dalcetrapib also decreased the number of patients who progressed from normoglycemia to prediabetes and increased the number who regressed from diabetes to no diabetes.

CONCLUSIONS

In patients with a recent acute coronary syndrome, incident diabetes is common and is reduced substantially by treatment with dalcetrapib.

A Comorbidity Model of Myocardial Ischemia/Reperfusion Injury and Hypercholesterolemia in Rat Cardiac Myocyte Cultures

Introduction

The use of comorbidity models is crucial in cardioprotective drug development. Hypercholesterolemia causes endothelial and myocardial dysfunction, as well as aggravates ischemia/reperfusion (I/R)-induced myocardial injury. Endogenous cardioprotective mechanisms against I/R are impaired in hyperlipidemic and hyperglycemic in vivo animal models. Therefore, our aim was to develop a medium throughput comorbidity cell-based test system of myocardial I/R injury, hypercholesterolemia and hyperglycemia that mimics comorbidity conditions.

Methods

Cardiac myocytes isolated from neonatal or adult rat hearts were cultured in control or in three different hypercholesterolemic media with increasing cholesterol content (hiChol) or hiChol + hyperglycemic medium, respectively. Each group was then subjected to simulated ischemia/reperfusion (SI/R) or corresponding normoxic condition, respectively. Cholesterol uptake was tested by Filipin staining in neonatal cardiac myocytes. Cell viability, total cell count and oxidative stress, i.e., total reactive oxygen species (ROS) and superoxide level were measured by fluorescent assays.

Results

Neonatal cardiac myocytes took up cholesterol from the different hiChol media at a concentration-dependent manner. In normoxia, viability of hiChol neonatal cardiac myocytes was not significantly changed, however, superoxide levels were increased as compared to vehicle. After SI/R, the viability of hiChol neonatal cardiac myocytes was decreased and total ROS level was increased as compared to vehicle. HiChol combined with hyperglycemia further aggravated cell death and oxidative stress in normoxic as well as in SI/R conditions. Viability of hiChol adult cardiac myocytes was significantly decreased and superoxide level was increased in normoxia and these changes were further aggravated by SI/R. HiChol combined with hyperglycemia further aggravated cell death, however level of oxidative stress increased only in normoxic condition.

Conclusion

HiChol rat cardiac myocytes showed reduction of cell viability and increased oxidative stress, which were further aggravated by SI/R and with additional hyperglycemia. This is the first demonstration that the combination of the current hypercholesterolemic medium and SI/R in cardiac myocytes mimics the cardiac pathology of the comorbid heart with I/R and hypercholesterolemia.

Assessment of serum tenascin-C and growth differentiation factor-15 among type 2 diabetes mellitus patients with and without acute coronary syndrome

Background

High prevalence of type 2 diabetes mellitus (T2DM) is associated with a higher prevalence of acute coronary syndrome (ACS). Inflammation is one of the important contributors to the pathogenesis and complications of coronary atherosclerotic plaque. Growth Differentiation Factor-15 (GDF-15) and Tenascin-C (TNC) play an important role in the initiation of atherosclerotic plaque as well as its rupture. The aim of the study was to evaluate the association between serum GDF-15, TNC, and the risk of ACS among T2DM patients.

Methods

Anthropometric parameters, routine biochemical investigations like liver and renal function tests, lipid profile, and Creatine Kinase-Total (CK-T), Creatine Kinase-MB (CK-MB) were measured in 42 T2DM patients with ACS and 42 T2DM patients. Serum GDF-15 and TNC were measured by Human Sandwich-ELISA kits.

Results

Serum GDF-15 and TNC levels were significantly higher in T2DM patients with ACS as compared to T2DM patients. Serum GDF-15 was significantly correlated with waist circumference, diastolic blood pressure, pulse, serum CK-T, and CK-MB. Serum TNC was significantly correlated with the pulse, serum CK-T, CK-MB, high-density lipoprotein-cholesterol, and blood urea nitro GEN. Multivariate linear regression analysis showed that waist circumference was independently positively associated with serum GDF-15.

Conclusions

T2DM patients with higher serum GDF-15 and TNC levels were at higher risk of acute coronary syndrome independent of other cardiovascular risk factors.

Relationships of coronary culprit-plaque characteristics with duration of diabetes mellitus in acute myocardial infarction: an intravascular optical coherence tomography study

Background

Diabetes mellitus (DM) or pre-diabetes status is closely associated with features of vulnerable coronary lesions in patients with stable coronary heart disease or acute coronary syndrome. However, the association between duration of diabetes and the morphologies and features of vulnerable plaques has not been fully investigated in patients with acute myocardial infarction (AMI).

Methods

We enrolled a total of 279 patients who presented with AMI between March 2017 and March 2019 and underwent pre-intervention optical coherence tomography imaging of culprit lesions. Patients with DM were divided into two subgroups: a Short-DM group with DM duration of < 10 years and a Long-DM group with DM duration of ≥ 10 years. Baseline clinical data and culprit-plaque characteristics were compared between patients without DM (the non-DM group), those in the Short-DM group, and those in the Long-DM group.

Results

Patients with DM represented 34.1% of the study population (95 patients). The Short- and Long-DM groups included 64 (67.4%) and 31 patients (32.6%), respectively. Glycated hemoglobin A1c (HbA1c) levels were significantly higher in the Long-DM group than the Non- or Short-DM groups (8.4% [Long-DM] versus 5.7% [Non-DM] and 7.6% [Short-DM], P < 0.001). In addition, the highest prevalence of lipid-rich plaques, thin-cap fibroatheroma (TCFA), and plaque ruptures of culprit lesions were observed in the Long-DM group (lipid-rich plaques: 80.6% [Long-DM] versus 52.2% [Non-DM] and 62.5% [Short-DM], P = 0.007; TCFA: 41.9% [Long-DM] versus 19.6% [Non-DM] and 31.3% [Short-DM], P = 0.012; plaque rupture: 74.2% [Long-DM] versus 46.7% [Non-DM] and 48.4% [Short-DM], P = 0.017). The frequency of calcification was significantly higher among patients with DM than among those without (62.1% versus 46.2%, P = 0.016); however, no significant differences were found between the DM subgroups (61.3% [Long-DM] versus 62.5% [Short-DM], P = 0.999).

Conclusions

Increased duration of DM combined with higher HbA1c levels influences culprit-plaque characteristics in patients with DM who suffer AMI. These findings might account for the higher risks of cardiac death in DM patients with long disease duration.

Trial registration This study is registered at clinicaltrials.gov as NCT03593928

Association of Prediabetes With Higher Coronary Atherosclerotic Burden Among Patients With First Diagnosed Acute Coronary Syndrome

Diabetes mellitus (DM) is associated with more extensive coronary atherosclerosis and more vulnerable plaque phenotypes. However, DM should not be considered a homogeneous and purely binary entity in terms of risk assessment. We evaluated the impact of prediabetic status on coronary atherosclerosis burden in patients with first-time acute coronary syndrome (ACS) who underwent urgent coronary angiography. The patients were divided into DM, prediabetes, and control groups. The 3-vessel disease (TVD) rates and SYNTAX and Gensini scoring systems for defining atherosclerotic burden were compared. The study was conducted in 469 consecutive patients admitted with a diagnosis of ACS. Of these, 250 patients were admitted at the first occurrence of ACS undergoing diagnostic coronary angiography. SYNTAX and Gensini scores and TVD rates were higher in prediabetic patients than in nondiabetic patients ( P = .004, P = .008, and P = .014, respectively), but similar in prediabetic and diabetic patients ( P = .912, P = .773, and P = 1.000, respectively). Coronary atherosclerosis burden is more advanced in prediabetic patients than in nondiabetic patients and is comparable between prediabetic and diabetic patients at first presentation of ACS. Cardiologists should not miss the opportunity to diagnose prediabetes and DM when patients present with an ACS.

Glycative and oxidative stress are associated with altered thrombus composition in diabetic patients with ST-elevation myocardial infarction

BACKGROUND

The role of type 2 diabetes (T2DM) on composition of thrombus has not been fully characterized in patients with ST-elevation myocardial infarction (STEMI).

AIMS

To elucidate the differences between diabetic and non-diabetic patients with STEMI in relation to the composition of coronary thrombus, and the potential association of these differences with glycated haemoglobin levels and markers of oxidative stress.

METHODS

Intracoronary thrombi from consecutive thrombus aspiration procedures in STEMI patients, 25 diabetic and 28 non-diabetic, were analyzed by immunofluorescence with confocal microscopy. Plasma biomarkers (P-selectin, vWF, PAI-1, t-PA, D-dimer, TF pathway markers, plasmin and CD34⁺) were measured in peripheral blood, and the oxidative capacity of plasma as indirect measure of oxidative stress was measured in parallel.

RESULTS

Patients with T2DM had higher levels of fibrin (P=0.03), P-selectin (P=0.0001), PAI-1 (P=0.03) and vWF (P=0.006) in the thrombus and higher plasma TF activity (P=0.01) compared to non-diabetics. TF activity and plasmin correlated with HbA₁C levels (R²=0.71, P=0.0001; R²=0.46, P=0.04, respectively) and TF was inversely correlated with TFPI (R²=-0.44, P=0.008) and tPA (R²=-0.48, P=0.003). Diabetic patients showed a higher oxidative response of plasma (26.47±6.88% vs 22.06±6.96% of oxidized lipids, P=0.04) (measured by H-NMR spectroscopy) that was associated to increased fibrin content into thrombus (R²=0.76, P=0.01).

CONCLUSION

Diabetic patients with STEMI display an increased thrombogenicity that results in a different thrombus composition respect to non-diabetic patients with STEMI. The increased thrombogenicity present in T2DM is related to higher glycoxidative stress, as quantified by HbA₁C levels and oxidative response in plasma.

The Roles of Autophagy in Acute Lung Injury Induced by Myocardial Ischemia Reperfusion in Diabetic Rats

Patients with diabetes are vulnerable to myocardial ischemia reperfusion (IR) injury, which may also induce acute lung injury (ALI) due to overaccumulation of reactive oxygen species (ROS) and inflammation cytokine in circulation. Despite autophagy plays a significant role in diabetes and pulmonary IR injury, the role of autophagy in ALI secondary to myocardial IR in diabetes remains largely elusive. We aimed to investigate pulmonary autophagy status and its roles in oxidative stress and inflammation reaction in lung tissues from diabetic rats subjected to myocardial IR. Control or diabetic rats were either treated with or without autophagy inducer rapamycin (Rap) or autophagy inhibitor 3-methyladenine (3-MA) before myocardial IR, which was achieved by occluding the left anterior descending coronary artery for 30 min and followed by reperfusion for 120 min. Diabetic rats subjected to myocardial IR showed more serious ALI with higher lung injury score and WET/DRY ratio and lower PaO₂ as compared with control rats, accompanied with impaired autophagy indicated by reduced LC-3II/LC-3I ratio and Beclin-1 expression, decreased superoxide dismutase (SOD) activity, and increased 15-F2t-Isoprostane formation in lung tissues, as well as increased levels of leukocyte count and proinflammatory cytokines in BAL fluid. Improving autophagy with Rap significantly attenuated all these changes, but the autophagy inhibitor 3-MA exhibited adverse or opposite effects as Rap. In conclusion, diabetic lungs are more vulnerable to myocardial IR, which are involved in impaired autophagy. Improving autophagy could attenuate ALI induced by myocardial IR in diabetic rats, possibly through inhibiting inflammatory reaction and oxidative stress.

Sex Differences in the Risk of Developing Acute Coronary Syndrome in Patients With Sleep Disorders: A Population-Based Cohort Study

Studies that focus on the relationship between sex and the risk of acute coronary syndrome (ACS) are scant. The current study investigated the effects of sex differences in the risk of developing ACS in patients with sleep disorders (SDs). This longitudinal population-based cohort study evaluated the incidence and risk of ACS development in 40,232 men and 65,519 women newly diagnosed with SDs between 2002 and 2008 from the Longitudinal Health Insurance Database. The follow-up period began from the entry date and ended on the date of an ACS event or December 31, 2010. Univariable and multivariable Cox proportional hazard regression models were conducted to estimate the sex differences in the risk of ACS. Men with SDs exhibited an increased incidence of ACS compared with women with SDs in all age- and comorbidity-specific subgroups. After covariates were adjusted, the men with SDs exhibited a 1.48-fold adjusted hazard ratio (aHR) of ACS compared with the women with SDs (95% confidence interval [CI] = 1.36-1.60). After age group stratification, the men with SDs in the young adult group exhibited the highest risk of subsequent ACS development compared with the women with SDs (aHR = 2.07, 95% CI = 1.69-2.55), followed by those in middle-aged adults (aHR = 1.52, 95% CI = 1.32-1.76) and older adults groups (aHR = 1.24, 95% CI = 1.11-1.39). This study determined that men with SDs, particularly young men, are at a higher risk of subsequent ACS development compared with women with SDs.

Risks of acute coronary syndrome in patients with osteoarthritis: a nationwide population-based cohort study

Recent studies have reported that osteoarthritis (OA) is related to inflammation and atherosclerosis. Studies on the relationship between OA and acute coronary syndrome (ACS) are scant. We evaluated the risk of ACS in OA patients of an Asian population. This longitudinal, population-based cohort study investigated the incidence and risk of ACS in 46,042 patients with newly diagnosed OA and 46,042 controls selected randomly from the general population and frequency matched according to age, sex, and entry year (2002-2003). The follow-up period ranged from the entry date until the date of an ACS event, loss to follow-up, or the end of 2010. We employed Cox proportional hazard models to estimate the effects of OA on the risk of ACS. The OA patients showed a 15 % higher risk of ACS than did the controls after adjustment for covariates (adjusted hazard ratio [aHR] = 1.15, 95 % confidence interval [CI] = 1.08-1.23). The risk of ACS in the OA patients was the greatest in young adults (aHR = 2.0, 95 % CI = 1.44-2.78), followed by middle-aged (aHR = 1.15, 95 % CI = 1.01-1.31) and older adults (aHR = 1.11, 95 % CI = 1.03-1.20). The risk of ACS was 1.96-fold in young adults with mild to moderate OA and 3.51-fold in young adults with severe OA compared with their counterparts without OA. OA carries an increased risk of ACS, particularly in young adults with severe OA. Clinicians should employ proactive strategies for preventing ACS occurrence in these patients.

Association between insulin receptor substrate-1 polymorphisms and high platelet reactivity with clopidogrel therapy in coronary artery disease patients with type 2 diabetes mellitus

BACKGROUND

The mechanisms leading to the high on-treatment platelet reactivity in diabetes patients are not fully elucidated. The genetic factors may be associated with the diminished antiplatelet efficacy of dual antiplatelet therapy. We investigated the possible association between insulin receptor substrate-1 (IRS-1) polymorphisms and high platelet reactivity in coronary artery disease (CAD) patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 674 CAD patients with T2DM were enrolled in this study. Platelet aggregation and platelet activation were assessed with light transmission aggregometry and flow cytometry analysis, respectively. Participants were divided into high platelet reactivity (HPR) group and non-HPR group according to their maximal platelet aggregation. Genotypes were identified by polymerase chain reaction and direct sequencing of genomic DNA. The association between IRS-1 genetic variants and platelet function was assessed.

RESULTS

There were 233 participants in the HPR group and 441 participants in the non-HPR group. G allele frequencies of rs13431554 were 27.7 % for the HPR group and 18.6 % for the non-HPR group (p < 0.001). Adenosine diphosphate and arachidonic acid induced platelet aggregation were significantly higher in G allele carriers compared with non-carriers (56.8 ± 16.2 vs 52.0 ± 17.9 %, p < 0.01, 28.9 ± 18.6 vs 25.2 ± 17.8 %, p < 0.01, respectively). We observed that P-selectin expression and PAC-1 binding were higher in G allele carriers compared with non-carriers (40.8 ± 12.4 vs 36.2 ± 13.8, p = 0.01; 43.7 ± 15.9 vs 38.7 ± 19.9, p = 0.03, respectively).

CONCLUSION

The G allele of rs13431554 in the IRS-1 gene was associated with a hyperreactive platelet phenotype in the CAD patients with T2DM.

Systematic review and meta-analysis of optimal P2Y12 blockade in dual antiplatelet therapy for patients with diabetes with acute coronary syndrome

Background

Patients with diabetes are at increased risk of acute coronary syndromes (ACS) and their mortality and morbidity outcomes are significantly worse following ACS events, independent of other comorbidities. This systematic review sought to establish the optimum management strategy with focus on P2Y₁₂ blockade in patients with diabetes with ACS.

Methods

MEDLINE (1946 to present) and EMBASE (1974 to present) databases, abstracts from major cardiology conferences and previously published systematic reviews were searched to June 2014. Relevant randomised control trials with clinical outcomes for P2Y₁₂ inhibitors in adult patients with diabetes with ACS were scrutinised independently by 2 authors with applicable data was extracted for primary composite end point of cardiovascular death, myocardial infarction (MI) and stroke; enabling calculation of relative risks with 95% CI with subsequent direct and indirect comparison.

Results

Four studies studied clopidogrel in patients with diabetes, with two (3122 patients) having primary outcome data showing superiority of clopidogrel against placebo with RR0.84 (95% CI 0.72–0.99). Irrespective of management strategy, the newer agents prasugrel (2 studies) and ticagrelor (1 study) had a lower primary event rate compared with clopidogrel; RR 0.80 (95% CI 0.66 to 0.97) and RR 0.89 (95% CI 0.77 to 1.02), respectively. When ticagrelor was indirectly compared with prasugrel, there was a trend to an improved primary outcome with prasugrel (RR 1.11 (95% CI 0.94 to 1.31)) particularly in those managed with percutaneous coronary intervention (PCI) (RR 1.23 (95% CI 0.95 to 1.59)). Prasugrel demonstrated a statistical superiority with prevention of further MI with RR 1.48 (95% CI 1.11 to 1.97). This was not at the expense of increased major thrombolysis in MI (TIMI) bleeding rates RR 0.94 (95% CI 0.59 to 1.51).

Conclusions

This meta-analysis shows the addition of a P2Y₁₂ inhibitor is superior to placebo, with a trend favouring the use of prasugrel in patients with diabetes with ACS, particularly those undergoing PCI.

The clinical burden of type 2 diabetes in patients with acute coronary syndromes: prognosis and implications for short- and long-term management

Type 2 diabetes mellitus (T2DM) is associated with increased morbidity and mortality in patients with acute coronary syndromes (ACS). Cardiometabolic risk factors, including hyperglycaemia, insulin resistance, atherogenic dyslipidaemia, increased visceral fat and inflammation, are associated with increased risk in this population and represent potential targets for treatment. In this review, management strategies for patients with T2DM post-ACS, both in the acute-care setting and in the long-term, are discussed. Although the benefits of long-term, aggressive, multifactorial risk factor modification are well established, a significant burden of recurrent events remains and the search for novel strategies continues. Several studies are assessing the potential cardiovascular (CV) benefits and safety of various classes of newer agents. Of these, AleCardio (aleglitazar), Examination of Cardiovascular Outcomes With Alogliptin versus Standard of Care in Patients With Type 2 Diabetes Mellitus and Acute Coronary Syndrome (EXAMINE; alogliptin) and Evaluation of LIXisenatide in Acute Coronary Syndrome (ELIXA; lixisenatide) specifically address patients with type 2 diabetes post-ACS. The mechanisms of action of these new therapies and aims of the CV outcome studies are briefly reviewed. The prevalence of type 2 diabetes continues to increase worldwide highlighting the need for new strategies that address the complex underlying processes that drive atherosclerosis and CV events in this high-risk patient population.

Impact of CYP2C19 polymorphism on clinical outcome following coronary stenting is more important in non-diabetic than diabetic patients

OBJECTIVE

The aim of this study was to examine the impact of CYP2C19 genotype on clinical outcome in coronary artery disease (CAD) patients with or without diabetes mellitus (DM).

METHODS

CYP2C19 polymorphism and DM are associated with increased risk of cardiovascular events during antiplatelet therapy following stent implantation. Platelet reactivity during clopidogrel therapy and CYP2C19 polymorphism were measured in 519 CAD patients (males 70%, age 69 years) treated with stent placement. Patients were divided into two groups; DM (n=249), and non-DM (n=270), and clinical events were evaluated according to the carrier state, which included at least one CYP2C19 loss-of-function allele.

RESULTS

The level of platelet reactivity and incidence of cardiovascular events were significantly different between Carriers and non-Carriers of the non-DM (platelet reactivity: 4501+/-1668 versus 3691+/-1714AU min, P<0.01; events, 32/178 versus 2/92, P<0.01, respectively), however, there was no difference in clinical outcome in the DM group (events, 34/168 versus 14/81, respectively, P=0.57). Multivariate analysis identified CYP2C19 loss-of-function allele carriage as an independent predictor of cardiovascular events in non-DM, but not in DM (non-DM, HR 7.180, 95% CI, 1.701 to 30.298, P=0.007; DM, HR 1.374, 95% CI, 0.394 to 4.792, P=0.618).

CONCLUSION

The impact of CYP2C19 polymorphism on clinical outcome seems to be more significant in non-DM compared with DM in patients with coronary stents.

Overexpression of STAMP2 suppresses atherosclerosis and stabilizes plaques in diabetic mice

Our research aims to evaluate the function of the STAMP2 gene, an important trigger in insulin resistance (IR), and explore its role in macrophage apoptosis in diabetic atherosclerotic vulnerable plaques. The characteristics of diabetic mice were measured by serial metabolite and pathology tests. The level of STAMP2 was measured by RT-PCR and Western blot. The plaque area, lipid and collagen content of brachiocephalic artery plaques were measured by histopathological analyses, and the macrophage apoptosis was measured by TUNEL. Correlation of STAMP2/Akt signaling pathway and macrophage apoptosis was validated by Ad-STAMP2 transfection and STAMP2 siRNA inhibition. The diabetic mice showed typical features of IR, hyperglycaemia. Overexpression of STAMP2 ameliorated IR and decreased serum glucose level. In brachiocephalic lesions, lipid content, macrophage quantity and the vulnerability index were significantly decreased by overexpression of STAMP2. Moreover, the numbers of apoptotic cells and macrophages in lesions were both significantly decreased. In vitro, both mRNA and protein expressions of STAMP2 were increased under high glucose treatment. P-Akt was highly expressed and caspase-3 was decreased after overexpression of STAMP2. However, expression of p-Akt protein was decreased and caspase-3 was increased when STAMP2 was inhibited by siRNA. STAMP2 overexpression could exert a protective effect on diabetic atherosclerosis by reducing IR and diminishing macrophage apoptosis.

Long-term prognostic impact of cystatin C on acute coronary syndrome octogenarians with diabetes mellitus

Objective

Cystatin C (Cys C) is a marker of renal dysfunction. Prior studies have shown that blood Cys C is related to the prognosis of coronary heart disease. The aim of the present study was to evaluate the long-term prognostic impact of Cys C on acute coronary syndrome (ACS) octogenarians with diabetes mellitus (DM).

Methods

We enrolled 660 consecutive ACS octogenarians who underwent coronary angiography and were classified into two groups based on diabetes. The baseline characters and Cys C level were measured on admission. Survival curve was calculated using the Kaplan-Meier method. Multivariate Cox regression was used to identify predictors of mortality and of major adverse cardiac events (MACE) rate.

Results

There were 223 and 398 patients in groups DM and non-DM who fulfilled the follow-up. The average follow-up period was 28 (IQR 16–38) months. Diastolic blood pressure (DBP) was lower, ratios of hypertension and chronic renal failure (CRF), fasting blood glucose, HbA1c and Cys C levels were higher in DM group than those in non-DM group (P<0.01). The cumulative survival of DM group was significantly lower than that of non-DM group in the long term (P = 0.018). All cause mortality and MACE of DM group were higher than those of non-DM group (P<0.05). The plasma Cys C concentration (OR = 3.32, 95% CI = 1.18-10.92, P = 0.023) was the uniqueness independent predictor for long-term all cause mortality. The plasma Cys C concentration (OR = 2.47, 95% CI = 1.07-7.86, P = 0.029) and Genesis score (OR = 1.01, 95% CI = 1.00-1.03, P = 0.043) were independent predictors for MACE in DM group. ROC curve analysis showed that the predictive cut-off value of Cys C for mortality of DM group was 1.605 (0.718, 0.704).

Conclusions

Cys C is an independent predictor for long-term mortality and MACE of ACS octogenarians with DM.

Mesenchymal stem cell transplantation for the infarcted heart: therapeutic potential for insulin resistance beyond the heart

Background

This study aimed to evaluate the efficacy of mesenchymal stem cell (MSC) transplantation to mitigate abnormalities in cardiac-specific and systemic metabolism mediated by a combination of a myocardial infarction and diet-induced insulin resistance.

Methods

C57BL/6 mice were high-fat fed for eight weeks prior to induction of a myocardial infarction via chronic ligation of the left anterior descending coronary artery. MSCs were administered directly after myocardial infarction induction through a single intramyocardial injection. Echocardiography was performed prior to the myocardial infarction as well as seven and 28 days post-myocardial infarction. Hyperinsulinemic-euglycemic clamps coupled with 2-[¹⁴C]deoxyglucose were employed 36 days post-myocardial infarction (13 weeks of high-fat feeding) to assess systemic insulin sensitivity and insulin-mediated, tissue-specific glucose uptake in the conscious, unrestrained mouse. High-resolution respirometry was utilized to evaluate cardiac mitochondrial function in saponin-permeabilized cardiac fibers.

Results

MSC administration minimized the decline in ejection fraction following the myocardial infarction. The greater systolic function in MSC-treated mice was associated with increased in vivo cardiac glucose uptake and enhanced mitochondrial oxidative phosphorylation efficiency. MSC therapy promoted reductions in fasting arterial glucose and fatty acid concentrations. Additionally, glucose uptake in peripheral tissues including skeletal muscle and adipose tissue was elevated in MSC-treated mice. Enhanced glucose uptake in these tissues was associated with improved insulin signalling as assessed by Akt phosphorylation and prevention of a decline in GLUT4 often associated with high-fat feeding.

Conclusions

These studies provide insight into the utility of MSC transplantation as a metabolic therapy that extends beyond the heart exerting beneficial systemic effects on insulin action.