Association between hyper- and hypoglycaemia and 2 year all-cause mortality risk in diabetic patients with acute coronary events

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.

Characteristics and outcomes of patients with type 1 diabetes admitted with acute coronary syndromes

AIMS

This study explored characteristics and outcomes of patients with type 1 diabetes mellitus (T1DM) and acute coronary syndromes (ACS).

METHODS

A retrospective analysis of patients with T1DM admitted with ACS to an Australian hospital was conducted. Risk factor targets were defined by 2021 European Society of Cardiology Guidelines. Outcomes were defined as an adverse cardiovascular event (ACS, unplanned revascularisation, heart failure, stroke, or cardiovascular death) or all-cause mortality within six-months after discharge.

RESULTS

61 patients were included [age 58.5 ± 12.8 years, 39 % female]. Dyslipidaemia (85 %), hypertension (75 %), smoking (28 %), prior coronary artery disease (CAD) (44 %), and microvascular complications (62 %) were common. HbA1c, low-density lipoprotein cholesterol, and blood pressure targets were attained in 12 %, 36 % and 47 %, respectively. ST-elevation myocardial infarction (65 % versus 7 %, p < 0.001) and revascularisation (77 % versus 41 %, p = 0.008) were more common in those without prior CAD. Peak inpatient blood glucose correlated directly with peak troponin (p = 0.011) and inversely with left ventricular ejection fraction (p = 0.027). Nineteen patients experienced an adverse six-month outcome, with peripheral neuropathy (p = 0.039) and in-hospital hypoglycaemia (p = 0.012) being independent predictors.

CONCLUSIONS

Patients with T1DM and ACS often do not meet guideline targets for cardiovascular risk factors, and frequently present with transmural infarctions. Dysglycemia and microvascular complications predict poorer outcomes.

Glycaemic Control in Patients Undergoing Percutaneous Coronary Intervention: What Is the Role for the Novel Antidiabetic Agents? A Comprehensive Review of Basic Science and Clinical Data

Coronary artery disease (CAD) remains one of the most important causes of morbidity and mortality worldwide, and revascularization through percutaneous coronary interventions (PCI) significantly improves survival. In this setting, poor glycaemic control, regardless of diabetes, has been associated with increased incidence of peri-procedural and long-term complications and worse prognosis. Novel antidiabetic agents have represented a paradigm shift in managing patients with diabetes and cardiovascular diseases. However, limited data are reported so far in patients undergoing coronary stenting. This review intends to provide an overview of the biological mechanisms underlying hyperglycaemia-induced vascular damage and the contrasting actions of new antidiabetic drugs. We summarize existing evidence on the effects of these drugs in the setting of PCI, addressing pre-clinical and clinical studies and drug-drug interactions with antiplatelet agents, thus highlighting new opportunities for optimal long-term management of these patients.

Long-term effects of the mean hemoglobin A1c levels after percutaneous coronary intervention in patients with diabetes

BACKGROUND/AIMS

The clinical benefit of strict blood glucose-lowering therapy for patients with coronary artery disease (CAD) is still debated. We aimed to evaluate the long-term outcomes of patients with diabetes who underwent percutaneous coronary intervention (PCI), according to the mean hemoglobin A1c (HbA1c) level after PCI.

METHODS

We evaluated 675 diabetes patients with CAD treated with PCI. We categorized the study population into three groups based on the mean observed HbA1c levels during the follow-up duration, as follows: aggressive control (AC) group (HbA1c level < 6.5%, n = 148), moderate control (MC) group (HbA1c level ≥ 6.5% and < 7.0%, n = 138), and uncontrolled (UC) group (HbA1c level ≥ 7.0%, n = 389). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCEs), defined as cardiac death, myocardial infarction, repeat target vessel revascularization, and stroke.

RESULTS

The mean HbA1c level of the AC group was significantly lower than that of the MC and UC groups (6.04% ± 0.36% vs. 6.74% ± 0.14% vs. 8.39% ± 1.20%, p < 0.001). The incidence of MACCEs was significantly lower in the AC group than in the MC and UC groups (16.0% vs. 24.3% vs. 26.3%, p = 0.010), mostly driven by the incidence of stroke (4.4% vs. 14.0% vs. 11.4%, p = 0.013). Multivariate Cox regression analysis showed that only the AC group was associated with a reduced rate of MACCEs (hazard ratio, 0.499; 95% confidence interval, 0.316 to 0.786; p = 0.004) compared with the UC group.

CONCLUSION

Our study showed that intensive glycemic control (HbA1c level < 6.5%) is associated with improved clinical outcomes after PCI in patients with diabetes.

Glucose-lowering therapy in patients undergoing percutaneous coronary intervention

The number of individuals with diabetes and pre-diabetes is constantly increasing. These conditions are overrepresented in patients undergoing percutaneous coronary intervention and are associated with adverse prognosis. Optimal glycaemic control during an acute coronary syndrome is a relevant factor for the improvement of longer-term outcomes. In addition, the implementation of newer glucose-lowering drugs with proven cardiovascular benefits has a remarkable impact on recurrence of events, hospitalisations for heart failure and mortality. In this narrative review, we outline the current state-of-the art recommendations for glucose-lowering therapy in patients with diabetes undergoing coronary intervention. In addition, we discuss the most recent evidence-based indications for revascularisation in patients with diabetes as well as the targets for glycaemic control post revascularisation. Current treatment goals for concomitant risk factor control are also addressed. Lastly, we acknowledge the presence of knowledge gaps in need of future research.

Does a strict glycemic control during acute coronary syndrome play a cardioprotective effect? Pathophysiology and clinical evidence

A hyperglycemic state, also in non-diabetic subjects, may be associated with acute coronary syndrome (ACS). Aim of this review is to describe the pathophysiologic association between ACS and hyperglycemic state, the protective mechanisms of a tight glycaemic control in ACS on CV outcomes, and the supporting clinical evidence. Several mechanisms may be responsible of a poor CV outcome in subjects with hyperglycemia during ACS. Endothelial NAPDH oxidase-2 (NOX2) activation in response to high glucose alters the balance between Raf/MAPK-dependent vasoconstriction and PI3K/Akt-dependent vasodilation in favour of constriction. Hyperglycaemia induces an overproduction of superoxide by the mitochondrial electron transport chain through different molecular mechanisms. Moreover, hyperglycaemia increases the size of the infarct by causing myocardial cell death through apoptosis and reducing the collateral blood flow. High FFA concentrations lead to toxicity mechanisms in acutely ischemic myocardium. On the other hand, a tight glycaemic control in ACS exerts a cardioprotective action by anti-inflammatory and anti-apoptotic mechanisms, anti-oxidative stress, endothelium protection, FFA reduction, anti-glucotoxic effect, IR and cardiac fuel metabolisms improvement, heart stem cells protection and reduced activation of adrenergic system. Unfortunately, the clinical studies supporting the above pathophysiological background are few and sometimes controversial, more likely due the risk of hypoglycemia linked to the insulin therapy generally used during ACS. Intriguingly, GLP-1 RA and SGLT2i, demonstrated highly effective in the cardiovascular prevention in high-risk subjects without the risk of hypoglycemia, might keep this cardioprotective effect even in acute conditions such as ASC.

Risk factors for hyperglycemia and hypoglycemia in adults with pharmacologically treated type 2 diabetes mellitus: a quantitative systematic review protocol

OBJECTIVE

The objective of this review is to identify and synthesize the risk factors for hyperglycemia or hypoglycemia in adults with pharmacologically treated type 2 diabetes mellitus in any scenarios and environments for health care.

INTRODUCTION

Studies around the world have investigated which factors are associated with episodes of alteration of blood glucose level. It is through the characterization of these factors that nurses can plan and intervene accurately in the control of serum glucose levels in people with diabetes.

INCLUSION CRITERIA

This review will include studies conducted among adults with pharmacologically treated type 2 diabetes mellitus in any scenarios and environments for health care. Studies should focus on risk factors for the variation of fasting glycemic levels lower than 3.9 mmol/L and higher than 7.21 mmol/L, as well as postprandial glycemic levels lower than 3.9 mmol/L and higher than 10 mmol/L.

METHODS

Databases to be searched include MEDLINE, Embase, CINAHL, PsycINFO, Web of Science, Scopus, LILACS, and ScienceDirect. Following the search, titles and abstracts will be screened by two independent reviewers for assessment against the inclusion criteria for the review. The full text of selected citations will be assessed in detail against the inclusion criteria, and studies selected for retrieval will be assessed by two independent reviewers for methodological validity using JBI critical appraisal tools. Studies will not be excluded based on their quality assessment. Data will be extracted using the standardized data extraction tools. Quantitative data will, where possible, be pooled in statistical meta-analysis.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO (CRD42019134755).

Impaired insulin secretion predicting unstable glycemic variability and time below range in type 2 diabetes patients regardless of glycated hemoglobin or diabetes treatment

AIMS/INTRODUCTION

To identify the coefficient of variation (CV) threshold for unstable glucose variability (GV) and hypoglycemia, and to characterize a patient population with unstable GV and hypoglycemia.

MATERIALS AND METHODS

This was an observational study that enrolled 284 Japanese outpatients with type 2 diabetes who underwent continuous glucose monitoring. The C-peptide index (CPI = [(fasting serum C-peptide) / (plasma glucose)] × 100) was used as a marker of endogenous insulin secretion. The CV threshold between stable and unstable GV was defined as the upper limit of the CV distribution in the subgroup of patients who did not receive insulin nor insulin secretagogues (relatively stable GV subgroup, n = 104). The optimal CV range corresponding to time below target range ≥4% was determined for all patients using receiver operating characteristic curve analysis. Various characteristics of patients with unstable GV and hypoglycemia were extracted using multivariate logistic regression analysis.

RESULTS

The upper limit of the CV in the relatively stable GV subgroup was 40. The optimal CV range corresponding to time below target range ≥4% was also defined as CV ≥40 (area under the curve 0.85) for all patients. The CPI was an independent risk for CV ≥40 (odds ratio 0.17, 95% confidence interval 0.04-0.50, P < 0.01). The optimal cut-off point for CPI to predict a CV cut-off value of 40 was equivalent to 0.81 (area under the curve 0.80).

CONCLUSIONS

A CV of 40 discriminates unstable GV and hypoglycemia from stable GV in Japanese outpatients with type 2 diabetes. Impaired insulin secretion might affect the stability of GV.

Stress-Induced Hyperglycaemia in Non-Diabetic Patients with Acute Coronary Syndrome: From Molecular Mechanisms to New Therapeutic Perspectives

Stress-induced hyperglycaemia (SIH) at hospital admission for acute coronary syndrome is associated with poor outcome, especially in patients without known diabetes. Nevertheless, insulin treatment in these subjects was not correlated with the reduction of mortality. This is likely due to the fact that SIH in the context of an acute coronary syndrome, compared to that in known diabetes, represents an epiphenomenon of other pathological conditions, such as adrenergic and renin-angiotensin system over-activity, hyperglucagonaemia, increase of circulating free fatty acids and pancreatic beta-cell dysfunction, which are not completely reversed by insulin therapy and so worsen the prognosis. Thus, SIH may be considered not only as a biomarker of organ damage, but also as an indicator of a more complex therapeutic strategy in these subjects. The aim of this review is to analyse the molecular mechanisms by which SIH may favour a worse prognosis in non-diabetic patients with acute coronary syndrome and identify new therapeutic strategies, in addition to insulin therapy, for a more appropriate treatment and improved outcomes.

Vildagliptin vs. insulin treatment alone in diabetic acute coronary syndrome patients

BACKGROUND

Vildagliptin, an oral antidiabetic of the dipeptidyl peptidase-4 (DPP-4) inhibitor drugs, exhibits an overall low risk of hypoglycemia with less frequent hypoglycemic events in type 2 diabetes mellitus (T2DM) patients than other antidiabetic drugs. We hypothesized that among hospitalized acute coronary syndrome (ACS) patients, the addition of vildagliptin to subcutaneous insulin therapy would reduce the risk of hypoglycemic events.

METHODS

One hundred ACS T2DM adult patients naive to DPP-4 inhibitors were enrolled during admission to the ICCU. Patients were divided into two randomized controlled groups: a subcutaneous rapid-acting insulin-only therapy group and an oral vildagliptin plus subcutaneous insulin group. The trial was open label with no placebo arm. Mean glucose values, insulin values given for correction per hospitalization, and the number of hypoglycemic events (glucose < 70 mg/dL) were documented.

RESULTS

Eight hypoglycemia events occurred in the insulin-only group and none in the insulin plus DPP-4 inhibitor group (P < 0.001). Patients with acute myocardial infarction experienced a higher number of hypoglycemic events compared with unstable angina diagnosed patients. No significant differences were found regarding glucose level (P = 0.462) and administered insulin units (P = 0.639).

CONCLUSIONS

In T2DM patients, the addition of DPP-4 inhibitors to routine subcutaneous insulin therapy may significantly reduce hypoglycemic events while maintaining acceptable recommended ranges of glucose. Further studies on a larger scale are required to verify these results and to support that DPP-4 inhibitors added to today's standard insulin-only treatment in hospitalized diabetic ACS patients may improve overall glycemic control and provide a potential treatment option in this challenging clinical setting.

Hypoglycemia during the Concomitant Use of Repaglinide and Clopidogrel in an Elderly Patient with Type 2 Diabetes and Severe Renal Insufficiency

Hypoglycemia should be avoided when treating patients with diabetes. Repaglinide is an insulin secretagogue with a low hypoglycemic risk because of its rapid- and short-acting effects. However, its blood concentration has been reported to increase in combination with clopidogrel, an antiplatelet drug, and in patients with severe renal insufficiency. We herein report an elderly patient with type 2 diabetes mellitus and severe renal insufficiency who received repaglinide and hypoglycemia three days after starting clopidogrel. The concomitant use of repaglinide and clopidogrel can lead to hypoglycemia, especially in patients with severe renal insufficiency.

Risk of severe hypoglycaemia and its impact in type 2 diabetes in DEVOTE

AIMS

To undertake a post-hoc analysis, utilizing a hypoglycaemia risk score based on DEVOTE trial data, to investigate if a high risk of severe hypoglycaemia was associated with an increased risk of cardiovascular events, and whether reduced rates of severe hypoglycaemia in patients identified as having the highest risk affected the risk of cardiovascular outcomes.

MATERIALS AND METHODS

The DEVOTE population was divided into quartiles according to patients' individual hypoglycaemia risk scores. For each quartile, the observed incidence and rate of severe hypoglycaemia, major adverse cardiovascular event (MACE) and all-cause mortality were determined to investigate whether those with the highest risk of hypoglycaemia were also at the greatest risk of MACE and all-cause mortality. In addition, treatment differences within each risk quartile [insulin degludec (degludec) vs. insulin glargine 100 units/mL (glargine U100)] in terms of severe hypoglycaemia, MACE and all-cause mortality were investigated.

RESULTS

Patients with the highest risk scores had the highest rates of severe hypoglycaemia, MACE and all-cause mortality. Treatment ratios between degludec and glargine U100 in the highest risk quartile were 95% confidence interval (CI) 0.56 (0.39; 0.80) (severe hypoglycaemia), 95% CI 0.76 (0.58; 0.99) (MACE) and 95% CI 0.77 (0.55; 1.07) (all-cause mortality).

CONCLUSIONS

The risk score demonstrated that a high risk of severe hypoglycaemia was associated with a high incidence of MACE and all-cause mortality and that, in this high-risk group, those treated with degludec had a lower incidence of MACE. These observations support the hypothesis that hypoglycaemia is a risk factor for cardiovascular events.

Development of a hypoglycaemia risk score to identify high-risk individuals with advanced type 2 diabetes in DEVOTE

AIMS

The ability to differentiate patient populations with type 2 diabetes at high risk of severe hypoglycaemia could impact clinical decision making. The aim of this study was to develop a risk score, using patient characteristics, that could differentiate between populations with higher and lower 2-year risk of severe hypoglycaemia among individuals at increased risk of cardiovascular disease.

MATERIALS AND METHODS

Two models were developed for the risk score based on data from the DEVOTE cardiovascular outcomes trials. The first, a data-driven machine-learning model, used stepwise regression with bidirectional elimination to identify risk factors for severe hypoglycaemia. The second, a risk score based on known clinical risk factors accessible in clinical practice identified from the data-driven model, included: insulin treatment regimen; diabetes duration; sex; age; and glycated haemoglobin, all at baseline. Both the data-driven model and simple risk score were evaluated for discrimination, calibration and generalizability using data from DEVOTE, and were validated against the external LEADER cardiovascular outcomes trial dataset.

RESULTS

Both the data-driven model and the simple risk score discriminated between patients at higher and lower hypoglycaemia risk, and performed similarly well based on the time-dependent area under the curve index (0.63 and 0.66, respectively) over a 2-year time horizon.

CONCLUSIONS

Both the data-driven model and the simple hypoglycaemia risk score were able to discriminate between patients at higher and lower risk of severe hypoglycaemia, the latter doing so using easily accessible clinical data. The implementation of such a tool (http://www.hyporiskscore.com/) may facilitate improved recognition of, and education about, severe hypoglycaemia risk, potentially improving patient care.

Using the BRAVO Risk Engine to Predict Cardiovascular Outcomes in Clinical Trials With Sodium-Glucose Transporter 2 Inhibitors

OBJECTIVE

This study evaluated the ability of the Building, Relating, Assessing, and Validating Outcomes (BRAVO) risk engine to accurately project cardiovascular outcomes in three major clinical trials-BI 10773 (Empagliflozin) Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients (EMPA-REG OUTCOME), Canagliflozin Cardiovascular Assessment Study (CANVAS), and Dapagliflozin Effect on Cardiovascular Events-Thrombolysis in Myocardial Infarction (DECLARE-TIMI 58) trial-on sodium-glucose cotransporter 2 inhibitors (SGLT2is) to treat patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Baseline data from the publications of the three trials were obtained and entered into the BRAVO model to predict cardiovascular outcomes. Projected benefits of reducing risk factors of interest (A1C, systolic blood pressure [SBP], LDL, or BMI) on cardiovascular events were evaluated, and simulated outcomes were compared with those observed in each trial.

RESULTS

BRAVO achieved the best prediction accuracy when simulating outcomes of the CANVAS and DECLARE-TIMI 58 trials. For EMPA-REG OUTCOME, a mild bias was observed (∼20%) in the prediction of mortality and angina. The effect of risk reduction on outcomes in treatment versus placebo groups predicted by the BRAVO model strongly correlated with the observed effect of risk reduction on the trial outcomes as published. Finally, the BRAVO engine revealed that most of the clinical benefits associated with SGLT2i treatment are through A1C control, although reductions in SBP and BMI explain a proportion of the observed decline in cardiovascular events.

CONCLUSIONS

The BRAVO risk engine was effective in predicting the benefits of SGLT2is on cardiovascular health through improvements in commonly measured risk factors, including A1C, SBP, and BMI. Since these benefits are individually small, the use of the complex, dynamic BRAVO model is ideal to explain the cardiovascular outcome trial results.

Effect of renin-angiotensin system inhibitors on major clinical outcomes in patients with acute myocardial infarction and prediabetes or diabetes after successful implantation of newer-generation drug-eluting stents

AIM

To investigate the comparative effectiveness of renin-angiotensin system inhibitor (RASI) therapy on major clinical outcomes in patients with acute myocardial infarction (AMI) and prediabetes or diabetes after successful percutaneous coronary intervention (PCI) with newer-generation drug-eluting stents (DESs).

METHODS

A total of 11,962 patients with AMI were divided into six groups according to glycemic status and the presence or absence of RASI therapy: normoglycemia (n = 3,080; RASI+ [n = 2,496], RASI- [n = 584]), prediabetes (n = 3,709; RASI+ [n = 2,944], RASI- [n = 765]), and diabetes (n = 5,173; RASI+ [n = 4,133], RASI- [n = 1,040]). The major endpoint was major adverse cardiac events (MACEs), defined as all-cause death, recurrent myocardial infarction (re-MI), or any repeat revascularization.

RESULTS

After adjustment, in RASI users, the cumulative incidence of re-MI of the diabetes group was significantly higher than that of the prediabetes group (aHR, 1.999; 95% CI, 1.153-3.467; p = 0.014). However, the cumulative incidences of MACEs, all-cause death, and any repeat revascularization were similar between the two groups during a 2-year follow-up period.

CONCLUSIONS

In the era of newer-generation DESs, RASI therapy did not reduce re-MI in patients with AMI and diabetes in this study.

Impact of Long-term Glycosylated Hemoglobin in Patients with Acute Myocardial Infarction: a retrospective cohort study

Little clinical evidence supports the strict implementation of glycemic control for diabetic patients with AMI. We aimed to demonstrate the effect of long-term glycemic control on mortality in patients with diabetes mellitus after acute myocardial infarction (AMI). Eight hundred and twenty-four consecutive diabetic patients were divided into three groups according to the mean hemoglobin (HbA1c) value: <6% (group A), ≥6% to <7.5% (group B), and ≥7.5% (group C). The best long-term mortality outcome was observed in Group B, followed by groups C and A. Groups B and C were further compared in-depth because the baseline characteristics of group A differed significantly. A Cox regression analysis indicated that Group C was associated with an adjusted hazard ratio (HR) of 1.55 [95% confidence interval (CI): 1.02-2.34, P = 0.038]. An inverse probability of treatment weight analysis was performed to compare groups B and C. Group C had significantly higher mortality, compared to group B (adjusted HR: 1.58; 95% CI: 1.21-2.06, P  < 0.001). In conclusion, Glycemic status was associated with the long-term survival outcome in diabetic patients after AMI. However, further study is needed to prove whether HbA1c-targeted glycemic control can effectively improve survival after AMI.

Association Between Perioperative Glycemic Control Strategy and Mortality in Patients With Diabetes Undergoing Cardiac Surgery: A Systematic Review and Meta-Analysis

OBJECTIVE

To analyze association between different perioperative glycemic control strategies and postoperative outcomes in patients with diabetes undergoing cardiac surgery.

METHODS

MEDLINE, Cochrane Library, Web of Science, EMBASE, Wanfang Data, China National Knowledge Infrastructure (CNKI) and China Biology Medicine (CBM) databases were searched from inception to January 31, 2019. Two researchers independently screened the literature, extracted data, and evaluated the risk of bias of included studies, and consensus was reached by discussion with a third researcher.

RESULTS

Six RCTs were included in the meta-analysis. We analyzed the effect of liberal (>180 mg/dl or 10.0 mmol/L), moderate (140-180 mg/dl or 7.8-10.0 mmol/L) and strict (<140 mg/dl or 7.8 mmol/L) glycemic control strategies in patients with diabetes undergoing cardiac surgery. The pooled results showed that strict glycemic control strategy was associated with a significant reduction in the risk of atrial fibrillation [OR = 0.48, 95%CI (0.32, 0.72), P < 0.001] and sternal wound infection [OR = 0.28, 95%CI (0.14, 0.54), P < 0.001], while there was no significant differences in postoperative mortality, stroke, and hypoglycemic episodes when compared with moderate control. In addition, there is no significant difference between moderate and liberal glycemic control strategies in postoperative mortality. However, moderate control was beneficial in reducing atrial fibrillation [OR = 0.28, 95%CI (0.13, 0.60), P = 0.001] compared with the liberal glycemic control strategy.

CONCLUSIONS

This meta-analysis showed when compared with moderate glycemic control strategy in patients with diabetes undergoing cardiac surgery, maintained strict glycemic control was associated with lower risk of atrial fibrillation and sternal wound infection. No benefit was found with liberal glycemic control strategy, so it could be a poor glycemic control strategy.

Diabetes Mellitus and Acute Myocardial Infarction: Impact on Short and Long-Term Mortality

Diabetes mellitus (DM) is an important risk factor for acute myocardial infarction (AMI) and a frequent co-morbidity in patients hospitalized with AMI, being present in about 30% of cases. Although current treatment of AMI has considerably improved survival in both patients with and without DM, the presence of DM still doubles the case fatality rate during both the acute phase of AMI and at long-term follow-up. This higher mortality risk of DM patients strongly indicates a particular need for better treatment options in these patients and suggests that intensive medical treatment, prolonged surveillance, and stringent control of other risk factors should be carefully pursued and maintained for as long as possible in them.In this review, we will focus on the close association between DM and in-hospital and long-term mortality in AMI patients. We will also aim at providing current evidence on the mechanisms underlying this association and on emerging therapeutic strategies, which may reduce the traditional mortality gap that still differentiates AMI patients with DM from those without.

Impact of Glycemic Variability and Hypoglycemia on the Mortality and Length of Hospital Stay among Elderly Patients in Brazil

BACKGROUND

Glycemic variability (GV) is an alternative diabetes-related parameter that has been associated with mortality and longer hospitalization periods. There is no ideal method for calculating GV. In this study, we used standard deviation and coefficient of variation due to their suitability for this sample and ease of use in daily clinical practice.

OBJECTIVE

This study aimed to investigate the association between GV, hypoglycemia, and the 90-day mortality and length of hospital stay (LOS) among non-critically ill hospitalized elderly patients.

METHODS

The medical records of 2,237 elderly patients admitted to the Zilda Arns Elderly Hospital over a 2.5-year period were reviewed. Hypoglycemia was defined as a glucose level <70 mg/dL (hypoglycemia alert value) and represented by the proportion of days in which the patient presented with this condition relative to the LOS. The Charlson comorbidity index was used to evaluate prognosis. Data were analyzed using multiple linear and logistic multivariate regression analyses.

RESULTS

Adjusted analysis of 687 patients (305 men [44.4%] and 382 women [55.6%], mean age of 77.86±9.25 years) revealed that GV was associated with a longer LOS (p=0.048). Mortality was associated with hypoglycemia (p=0.005) and mean patient-day blood glucose level (p=0.036). Variables such as age (p<0.001), Charlson score (p<0.001), enteral diet (p<0.001), and corticosteroid use (p=0.007) were also independently associated with 90-day mortality.

CONCLUSION

Increased GV during hospitalization is independently associated with a longer LOS and hypoglycemia in non-critically ill elderly patients, while the mean patient-day blood glucose is associated with increased mortality.

Glucose-lowering therapy and cardiovascular outcomes in patients with type 2 diabetes mellitus and acute coronary syndrome

Diabetes is a common comorbidity in patients hospitalized for an acute coronary syndrome event, and prevalence is increasing. Among patients hospitalized with acute myocardial infarction, diabetes can be an independent predictor of mortality and new cardiovascular events; both short- and long-term outcomes are worse for patients with diabetes relative to those without, and undiagnosed diabetes is associated with greater mortality. The impact of glycemic control on cardiovascular outcomes and the best approach to treat hyperglycemia upon hospital admission for acute coronary syndrome in patients with or without known diabetes remain open questions. This review assesses available evidence for hyperglycemia management at the time of admission for acute coronary syndrome and, thereafter, finds that (1) admission plasma glucose plays a role in predicting adverse events, especially in patients with unknown diabetes; (2) glycated haemoglobin is a likely predictor of events in patients with unknown diabetes; and (3) hypoglycemia at the time of acute myocardial infarction hospital admission is an important predictor for mortality in patients with and without diabetes. Whether glucose-targeted insulin and glucose infusion have advantages over glucose-insulin-potassium infusion remains controversial. Evidence for the effect of novel glucose-lowering agents used at the time of an acute cardiovascular event is limited and requires more dedicated studies.

A novel form of glycolytic metabolism-dependent cardioprotection revealed by PKCα and β inhibition

KEY POINTS

Acute hyperglycaemia at the time of a heart attack worsens the outcome for the patient. Acute hyperglycaemia is not limited to diabetic patients and can be due to a stress response in non-diabetics. This study suggests that the damaging cardiac effects of hyperglycaemia can be reversed by selective PKC inhibition. If PKCα/β isoforms are inhibited, then high glucose itself becomes protective against ischaemic damage. Selective PKC inhibition may therefore be a useful therapeutic tool to limit the damage that can occur during a heart attack by stress-induced hyperglycaemia.

ABSTRACT

Hyperglycaemia has a powerful association with adverse prognosis for patients with acute coronary syndromes (ACS). Previous work shows that high glucose prevents ischaemic preconditioning and causes electrical and mechanical disruption via protein kinase C α/β (PKCα/β) activation. The present study aimed to: (i) determine whether the adverse clinical association of hyperglycaemia in ACS can be replicated in preclinical cellular models of ACS and (ii) determine the importance of PKCα/β activation to the deleterious effect of glucose. Freshly isolated rat, guinea pig or rabbit cardiomyocytes were exposed to simulated ischaemia after incubation in the presence of normal (5 mm) or high (20 mm) glucose in the absence or presence of small molecule or tat-peptide-linked PKCαβ inhibitors. In each of the four conditions, the following hallmarks of cardioprotection were recorded using electrophysiology or fluorescence imaging: cardiomyocyte contraction and survival, action potential stability and time to failure, intracellular calcium and ATP, mitochondrial depolarization, ischaemia-sensitive leak current, and time to K_ir 6.2 opening. High glucose alone resulted in decreased cardiomyocyte contraction and survival; however, it also imparted cardioprotection in the presence of PKCα/β inhibitors. This cardioprotective phenotype displayed improvements in all of the measured parameters and decreased myocardium damage during whole heart coronary ligation experiments. High glucose is deleterious to cellular and whole-heart models of simulated ischaemia, in keeping with the clinical association of hyperglycaemia with an adverse outcome in ACS. PKCαβ inhibition revealed high glucose to show a cardioprotective phenotype in this setting. The results of the present study suggest the potential for the therapeutic application of PKCαβ inhibition in ACS associated with hyperglycaemia.

Glycemic Variability Is a Powerful Independent Predictive Factor of Midterm Major Adverse Cardiac Events in Patients With Diabetes With Acute Coronary Syndrome

OBJECTIVE

Acute glucose fluctuations are associated with hypoglycemia and are emerging risk factors for cardiovascular outcomes. However, the relationship between glycemic variability (GV) and the occurrence of midterm major cardiovascular events (MACE) in patients with diabetes remains unclear. This study investigated the prognostic value of GV in patients with diabetes and acute coronary syndrome (ACS).

RESEARCH DESIGN AND METHODS

This study included consecutive patients with diabetes and ACS between January 2015 and November 2016. GV was assessed using SD during initial hospitalization. MACE, including new-onset myocardial infarction, acute heart failure, and cardiac death, were recorded. The predictive effects of GV on patient outcomes were analyzed with respect to baseline characteristics and cardiac status.

RESULTS

A total of 327 patients with diabetes and ACS were enrolled. MACE occurred in 89 patients (27.2%) during a mean follow-up of 16.9 months. During follow-up, 24 patients (7.3%) died of cardiac causes, 35 (10.7%) had new-onset myocardial infarction, and 30 (9.2%) were hospitalized for acute heart failure. Multivariable logistic regression analysis showed that GV >2.70 mmol/L, a Synergy between PCI with Taxus and Cardiac Surgery (SYNTAX) score >34, and reduced left ventricular ejection fraction of <40% were independent predictors of MACE, with odds ratios (ORs) of 2.21 (95% CI 1.64-2.98; P < 0.001), 1.88 (1.26-2.82; P = 0.002), and 1.71 (1.14-2.54; P = 0.009), respectively, whereas a Global Registry of Acute Coronary Events (GRACE) risk score >140 was not (OR 1.07 [0.77-1.49]; P = 0.69).

CONCLUSIONS

A GV cutoff value of >2.70 mmol/L was the strongest independent predictive factor for midterm MACE in patients with diabetes and ACS.

Glycemic variability in the development of cardiovascular complications in diabetes

Diabetes mellitus represents a major risk factor for the development of coronary artery disease and other vascular complications. Glycated haemoglobin, fructosamine, and fasting blood glucose levels are partial parameters to exhaustively describe patient dysglycemic status. Thus, recently the new concept of glycemic variability has emerged, including information about two major aspects: the magnitude of blood glucose excursions (from nadir to peak, thus lower and higher spikes) and the time intervals in which these fluctuations occur. Despite the lack of consensus regarding the most appropriate definition and tools for its assessment, glycemic variability seems to have more deleterious effects than sustained hyperglycemia in the pathogenesis of diabetic cardiovascular complications. This manuscript aimed to review the most recent evidence on glycemic variability and its potential use in everyday clinical practice to identify diabetic patients at higher risk of cardiovascular complications and thus needing stricter monitoring and treatment.

Effect of short- and long-term diabetes control on in-hospital and one year mortality rates in hospitalized patients with diabetic foot

INTRODUCTION

It remains unclear whether diabetic patients with diabetic foot complications benefit from strict glycemic control during hospitalization The present study investigates the effect of short- and long-term diabetes control on hospital outcomes including: in-hospital and one year mortality rates, length of hospital stay and the rate of repeated admissions.

METHODS

Type 2 diabetic patients (n = 341) were hospitalized for diabetic foot complications at Wolfson Medical Center over a 5 year period (2008-2012). The adequate short-term glycemic control was defined as average glucose levels between 110 and 180 mg/dL. HbA_1c values below 7% were defined as adequate long-term glycemic control.

RESULTS

The average glucose levels during hospitalization were 179 ± 45 mg/dL and 40% of the measurements were between 110 and 180 mg/dL. Mean admission HBA_1c levels were 8.43% ± 2.26%, and 31% of the values were below 7%. The mean length of hospital stay was 24.3 ± 22.6 days, 15.0% of the patients needed surgical intervention during admission, the in-hospital mortality rate was 10.3%, and the rate of 1-year readmission was 25.1%. Adequate diabetes control during hospitalization was not significantly associated with reduced in-hospital mortality (hazard ratio, 0.454, 95% confidence interval 0.186-1.103, p = 0.081). However, adequate diabetes control during hospitalization lead to significantly decreased one year mortality (hazard ratio, 0.269, 95% confidence interval 0.707-0.101, p = 0.009). Adequate diabetes control during hospitalization did not affect the length of hospital stay or the rate of repeated admission.

CONCLUSIONS

Improved glucose control during hospital admission (levels between 110 and 180 mg/dL) was associated with reduction of one year mortality.

Perioperative Management of Hyperglycemia and Diabetes in Cardiac Surgery Patients

Perioperative hyperglycemia is common after cardiac surgery, reported in 60% to 90% of patients with diabetes and in approximately 60% of patients without history of diabetes. Many observational and prospective randomized trials in critically-ill cardiac surgery patients support a strong association between hyperglycemia and poor clinical outcome. Despite ongoing debate about the optimal glucose target, there is strong agreement that improved glycemic control reduces perioperative complications.

Hyperglycemia in Acute Coronary Syndromes: From Mechanisms to Prognostic Implications

Numerous studies have documented that hyperglycemia is frequent in patients hospitalized with acute coronary syndromes, affects patients with and without established diabetes, and is associated with adverse outcomes, with incremental increase in risk of mortality and complications observed across the spectrum of glucose elevations. This article reviews present knowledge about the association between glucose levels and outcomes of patients hospitalized with acute coronary syndromes; describes available data regarding inpatient glucose management in this patient group, and comparative data across the spectrum of critically ill hospitalized patients; addresses some controversies in this field; and offers practical recommendations for patient management based on existing data.

Patient, health service factors and variation in mortality following resuscitated out-of-hospital cardiac arrest in acute coronary syndrome: Analysis of the Myocardial Ischaemia National Audit Project

AIMS

To determine patient and health service factors associated with variation in hospital mortality among resuscitated cases of out-of-hospital cardiac arrest (OHCA) with acute coronary syndrome (ACS).

METHODS

In this cohort study, we used the Myocardial Ischaemia National Audit Project database to study outcomes in patients hospitalised with resuscitated OHCA due to ACS between 2003 and 2015 in the United Kingdom. We analysed variation in inter-hospital mortality and used hierarchical multivariable regression models to examine the association between patient and health service factors with hospital mortality.

RESULTS

We included 17604 patients across 239 hospitals. Overall hospital mortality was 28.7%. In 94 hospitals that contributed at least 60 cases, mortality by hospital ranged from 10.7% to 66.3% (median 28.6%, IQR 23.2% to 39.1%)). Patient and health service factors explained 36.1% of this variation. After adjustment for covariates, factors associated with higher hospital mortality included increasing serum glucose, ST-Elevation myocardial infarction (STEMI) diagnosis, and initial admission to a primary percutaneous coronary intervention (pPCI) capable hospital. Hospital OHCA volume was not associated with mortality. The key modifiable factor associated with lower mortality was early reperfusion therapy in STEMI patients.

CONCLUSION

There was wide variation in inter-hospital mortality following resuscitated OHCA due to ACS that was only partially explained by patient and health service factors. Hospital OHCA volume and pPCI capability were not associated with lower mortality. Early reperfusion therapy was associated with lower mortality in STEMI patients.

Relationship of Hyperglycaemia, Hypoglycaemia, and Glucose Variability to Atherosclerotic Disease in Type 2 Diabetes

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is known to be associated with increased cardiovascular risk. The aim of this study was therefore to investigate the independent effects of hyperglycaemia, hypoglycaemia, and glucose variability on microvascular and macrovascular disease in T2DM.

METHODS

Subjects with T2DM of <10 years duration and on stable antiglycaemic treatment underwent carotid intima-media thickness (CIMT), ankle-brachial index (ABI), albumin-creatinine ratio (ACR), and HbA_1c measurement, as well as 72-hour continuous glucose monitoring. Macrovascular disease was defined as one or more of the following: history of ischaemic heart disease (IHD), cerebrovascular accident (CVA), ABI < 0.9, or abnormal CIMT.

RESULTS

The study population comprised 121 subjects with T2DM (89 males : 32 females). The mean age was 62.6 years, and the mean DM duration was 3.7 years. Macrovascular disease was present in 71 patients (58.7%). In multivariate logistic regression analysis, body surface area (BSA) (OR 18.88 (95% CI 2.20-156.69), p = 0.006) and duration of blood glucose (BG) < 3.9 mmol/L (OR 1.12 (95% CI 1.014-1.228), p = 0.024) were independent predictors of macrovascular disease. BSA (OR 12.6 (95% CI 1.70-93.54), p = 0.013) and duration of BG < 3.9 mmol/L (OR 1.09 (95% CI 1.003-1.187), p = 0.041) were independent predictors of abnormal CIMT. Area under the curve for BG > 7.8 mmol/L (β = 15.83, p = 0.005) was the sole independent predictor of albuminuria in generalised linear regression.

CONCLUSIONS

This study demonstrates that hypoglycaemia is associated with the occurrence of atherosclerotic disease while hyperglycaemia is associated with microvascular disease in a Caucasian population with T2DM of recent duration.

α-Glucosidase inhibitor miglitol attenuates glucose fluctuation, heart rate variability and sympathetic activity in patients with type 2 diabetes and acute coronary syndrome: a multicenter randomized controlled (MACS) study

Background

Little is known about clinical associations between glucose fluctuations including hypoglycemia, heart rate variability (HRV), and the activity of the sympathetic nervous system (SNS) in patients with acute phase of acute coronary syndrome (ACS). This pilot study aimed to evaluate the short-term effects of glucose fluctuations on HRV and SNS activity in type 2 diabetes mellitus (T2DM) patients with recent ACS. We also examined the effect of suppressing glucose fluctuations with miglitol on these variables.

Methods

This prospective, randomized, open-label, blinded-endpoint, multicenter, parallel-group comparative study included 39 T2DM patients with recent ACS, who were randomly assigned to either a miglitol group (n = 19) or a control group (n = 20). After initial 24-h Holter electrocardiogram (ECG) (Day 1), miglitol was commenced and another 24-h Holter ECG (Day 2) was recorded. In addition, continuous glucose monitoring (CGM) was performed throughout the Holter ECG.

Results

Although frequent episodes of subclinical hypoglycemia (≤4.44 mmo/L) during CGM were observed on Day 1 in the both groups (35% of patients in the control group and 31% in the miglitol group), glucose fluctuations were decreased and the minimum glucose level was increased with substantial reduction in the episodes of subclinical hypoglycemia to 7.7% in the miglitol group on Day 2. Holter ECG showed that the mean and maximum heart rate and mean LF/HF were increased on Day 2 in the control group, and these increases were attenuated by miglitol. When divided 24-h time periods into day-time (0700–1800 h), night-time (1800–0000 h), and bed-time (0000–0700 h), we found increased SNS activity during day-time, increased maximum heart rate during night-time, and glucose fluctuations during bed-time, which were attenuated by miglitol treatment.

Conclusions

In T2DM patients with recent ACS, glucose fluctuations with subclinical hypoglycemia were associated with alterations of HRV and SNS activity, which were mitigated by miglitol, suggesting that these pathological relationships may be a residual therapeutic target in such patients.

Trial registration Unique Trial Number, UMIN000005874 (https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000006929)

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0571-1) contains supplementary material, which is available to authorized users.

Admission Glucose and In-hospital Mortality after Acute Myocardial Infarction in Patients with or without Diabetes: A Cross-sectional Study

Background:

Hyperglycemia on admission has been found to elevate risk for mortality and adverse clinical events after acute myocardial infarction (AMI), but there are evidences that the relationship of blood glucose and mortality may differ between diabetic and nondiabetic patients. Prior studies in China have provided mixed results and are limited by statistical power. Here, we used data from a large, nationally representative sample of patients hospitalized with AMI in China in 2001, 2006, and 2011 to assess if admission glucose is of prognostic value in China and if this relationship differs depending on the presence or absence of diabetes.

Methods:

Using a nationally representative sample of patients with AMI in China in 2001, 2006, and 2011, we categorized patients according to their glucose levels at admission (< 3.9, 3.9–7.7, 7.8–11.0, and ≥11.1 mmol/L) and compared in-hospital mortality across these admission glucose categories, stratified by diabetes status. Among diabetic and nondiabetic patients, separately, we employed logistic regression to assess the differences in outcomes across admission glucose levels while adjusting for the same covariates.

Results:

Compared to patients with euglycemia (5.8%), patients with moderate hyperglycemia (13.1%, odds ratio [OR] = 2.44, 95% confidence interval [CI, 2.08–2.86]), severe hyperglycemia (21.5%, OR = 4.42, 95% CI [3.78–5.18]), and hypoglycemia (13.8%, OR = 2.59, 95% CI [1.68–4.00]), all had higher crude in-hospital mortality after AMI regardless of the presence of recognized diabetes mellitus. After adjustment for patients’ characteristics and clinical status, however, the relationship between admission glucose and in-hospital mortality was different for diabetic and nondiabetic patients (P for interaction = 0.045). Among diabetic patients, hypoglycemia (OR = 3.02, 95% CI [1.20–7.63]), moderate hyperglycemia (OR = 1.75, 95% CI [1.04–2.92]), and severe hyperglycemia (OR = 2.97, 95% CI [1.87–4.71]) remained associated with elevated risk for mortality, but among nondiabetic patients, only patients with moderate hyperglycemia (OR = 2.34, 95% CI [1.93–2.84]) and severe hyperglycemia (OR = 3.92, 95% CI [3.04–5.04]) were at elevated mortality risk and not hypoglycemia (OR = 1.12, 95% CI [0.60–2.08]). This relationship was consistent across different study years (P for interaction = 0.900).

Conclusions:

The relationship between admission glucose and in-hospital mortality differs for diabetic and nondiabetic patients. Hypoglycemia was a bad prognostic marker among diabetic patients alone. The study results could be used to guide risk assessment among AMI patients using admission glucose.

Trial Registration:

www.clinicaltrials.gov, NCT01624883; https://clinicaltrials.gov/ct2/show/NCT01624883

Management of critically ill patients with diabetes

Disorders of glucose homeostasis, such as stress-induced hypoglycemia and hyperglycemia, are common complications in patients in the intensive care unit. Patients with preexisting diabetes mellitus (DM) are more susceptible to hyperglycemia, as well as a higher risk from glucose overcorrection, that may results in severe hypoglycemia. In critically ill patients with DM, it is recommended to maintain a blood glucose range between 140-180 mg/dL. In neurological patients and surgical patients, tighter glycemic control (i.e., 110-140 mg/d) is recommended if hypoglycemia can be properly avoided. There is limited evidence that shows that critically ill diabetic patients with a glycosylated hemoglobin levels above 7% may benefit from looser glycemic control, in order to reduce the risk of hypoglycemia and significant glycemic variability.

A Pilot Study to Evaluate the Effectiveness of Glargine and Multiple Injections of Lispro in Patients With Type 2 Diabetes Receiving Tube Feedings in a Cardiovascular Intensive Care Unit

BACKGROUND

The purpose of this study was to evaluate the effectiveness of insulin lispro and insulin glargine at controlling blood glucose in patients with type 2 diabetes mellitus in a cardiovascular intensive care unit (CICU) and receiving enteral tube feedings.

METHODS

This was a pilot study with a retrospective control designed to evaluate an insulin protocol in patients admitted to the CICU in a level 3 teaching institution. Patients were 18-99 years of age with type 2 diabetes mellitus, receiving bolus tube feeding. The control group included 24 patients who were retrospectively studied to determine mean blood glucose level. A glycemic management protocol was developed that included glargine and lispro insulins to maintain blood glucose levels between 80 and 140 mg/dL. The study group consisted of 28 patients who were treated according to the glycemic management protocol.

RESULTS

The mean blood glucose level of the retrospective control group was 225 mg/dL. The mean blood glucose level of the intervention group was 148 mg/dL. After protocol institution, 48.6% of blood glucose levels were within the goal blood glucose range of 80-140 mg/dL vs 8.26% (p = .01) before protocol institution. Hyperglycemia decreased from 90.0% to 47.2% (p < .0001) with institution of the protocol.

CONCLUSIONS

The average blood glucose of the intervention group was slightly above the goal blood glucose range of 80-140 mg/dL; however, the study protocol was superior to the previous CICU blood glucose management protocol.

Admission hyperglycemia and adverse outcomes in diabetic and non-diabetic patients with non-ST-elevation myocardial infarction undergoing percutaneous coronary intervention

Background

The association between admission hyperglycemia and adverse outcomes in patients with non-ST-segment elevation myocardial infarction (NSTEMI) undergoing percutaneous coronary intervention (PCI) has not been well studied, and the optimal plasma glucose cut-off values for prognosis for NSTEMI patients with and without diabetes have not been determined.

Methods

According to glucose level and diabetes status, consecutive NSTEMI patients undergoing PCI (n = 890) were divided into four groups: without diabetes mellitus (DM) and admission plasma glucose (APG) <144 or ≥144 mg/dL; or with DM and APG <180 or ≥180 mg/dL. All patients were followed up at 30 days and 3 years after discharge, and the outcomes were assessed.

Results

Admission hyperglycemia was found in 44 and 28% of the DM and non-DM patients, respectively. Multivariable analyses showed that the APG level was an independent predictor of 30-day and 3-year MACEs. Receiver operating characteristic curve analysis revealed that the appropriate cut-off values were 178 and 145 mg/dL for patients with and without DM, respectively, or 157 mg/dL for all patients.

Conclusions

Admission hyperglycemia may be used to predict 30-day and 3-year MACEs in patients with NSTEMI undergoing PCI, irrespective of diabetes status. However, the optimal admission glucose cut-off values for predicting prognosis differ for patients with or without DM.

Does HbA1c Level Have Clinical Implications in Diabetic Patients Undergoing Coronary Artery Bypass Grafting? A Systematic Review and Meta-Analysis

AIMS/INTRODUCTION

The aim of the present study was to investigate whether HbA1c was related to clinical outcomes in diabetic patients undergoing CABG surgery.

MATERIALS AND METHODS

A literature search was carried out satisfying the predefined inclusion criteria from Pubmed, Embase, and Cochrane Library. Differences were expressed as odds ratios (ORs) with 95% confidence intervals (CIs) to assess the relationships of preoperative HbA1c levels and clinical prognosis in diabetic patients.

RESULTS

7895 diabetic patients undergoing CABG surgery from eight published studies were finally involved in this meta-analysis. Combined analyses revealed that the higher HbA1c level was significantly associated with increased risks of all-cause mortality (OR 1.56, 95%CI 1.29-1.88), myocardial infarction (OR 2.37, 95%CI 1.21-4.64), and stroke (OR 2.07, 95%CI 1.29-3.32) after CABG surgery. However, there was no significant relationship between HbA1c levels and renal failure (OR 2.08, 95%CI 0.96-4.54) in diabetic patients undergoing CABG surgery.

CONCLUSIONS

Our meta-analysis demonstrated that the HbA1c level is potentially associated with increased risks of all-cause mortality, myocardial infarction, and stroke in diabetic subjects undergoing CABG surgery. However, further clinical studies with larger sample sizes and longer follow-up period are urgently warranted.

Under-treatment of type 2 diabetes: Causes and outcomes of clinical inertia

AIMS

To assess the impact of clinical inertia on type 2 diabetes (T2D) care.

METHODS

PubMed database search from January 2000 until December 2015.

RESULTS

Clinical inertia, defined as resistance to initiate or intensify treatment in a patient not at the evidence-based glycated haemoglobin goal, is conservatively estimated to occur in at least 25% of patients with T2D. Consequently, many patients with diagnosed and treated T2D experience extended periods, in some cases years, of ineffectively controlled hyperglycaemia, potentially causing serious microvascular and macrovascular harm. Delayed treatment does not appear to be specific to primary care, but also occurs in the specialist setting. The causes of clinical inertia appear to be complex, involving both reasonable and unacceptable delays on the part of the clinician and poor compliance with treatment regimens on the part of the patient. Evidence suggests that the clinical and organisational context may be particularly important in reinforcing clinical inertia, notably the increasingly severe time constraints for diagnosis and management of multiple morbidities, consideration of complex guidelines, assessment of cost and appreciation of patient concerns, all of which may hamper prioritisation of the important issue of under-treatment.

CONCLUSIONS

Since the pharmacotherapeutic tools for good control of blood glucose exist in all advanced healthcare systems, initiatives to address the important and widespread problem of clinical inertia may require focused campaigns that encourage attention to guideline recommendations and their adaptation for individualised care.

A Simple Risk Stratification Model for ST-Elevation Myocardial Infarction (STEMI) from the Combination of Blood Examination Variables: Acute Myocardial Infarction-Kyoto Multi-Center Risk Study Group

Background

Many mortality risk scoring tools exist among patients with ST-elevation Myocardial Infarction (STEMI). A risk stratification model that evaluates STEMI prognosis more simply and rapidly is preferred in clinical practice.

Methods and Findings

We developed a simple stratification model for blood examination by using the STEMI data of AMI-Kyoto registry in the derivation set (n = 1,060) and assessed its utility for mortality prediction in the validation set (n = 521). We selected five variables that significantly worsen in-hospital mortality: white blood cell count, hemoglobin, C-reactive protein, creatinine, and blood sugar levels at >10,000/μL, <10 g/dL, >1.0 mg/dL, >1.0 mg/dL, and >200 mg/dL, respectively. In the derivation set, each of the five variables significantly worsened in-hospital mortality (p < 0.01). We developed the risk stratification model by combining laboratory variables that were scored based on each beta coefficient obtained using multivariate analysis and divided three laboratory groups. We also found a significant trend in the in-hospital mortality rate for three laboratory groups. Therefore, we assessed the utility of this model in the validation set. The prognostic discriminatory capacity of our laboratory stratification model was comparable to that of the full multivariable model (c-statistic: derivation set vs validation set, 0.81 vs 0.74). In addition, we divided all cases (n = 1,581) into three thrombolysis in myocardial infarction (TIMI) risk index groups based on an In TIME II substudy; the cases were further subdivided based on this laboratory model. The high laboratory group had significantly high in-hospital mortality rate in each TIMI risk index group (trend of in-hospital mortality; p < 0.01).

Conclusions

This laboratory stratification model can predict in-hospital mortality of STEMI simply and rapidly and might be useful for predicting in-hospital mortality of STEMI by further subdividing the TIMI risk index.

Comparison of cardiovascular and metabolic outcomes in people with type 2 diabetes on insulin versus non-insulin glucose-lowering therapies (GLTs): A systematic review and meta-analysis of clinical trials

OBJECTIVES

To compare the cardiovascular and metabolic outcomes of Insulin versus non-insulin glucose lowering therapy (GLT).

METHODS

We included randomised control trials (RCTs) which randomised patients aged >18years with Type 2 Diabetes (T2D) to insulin vs non-insulin GLT. We used risk ratios (RR), risk difference (RD) and odds ratios (OR) with 95% confidence interval (95%CI) to analyse the treatment effects of dichotomous outcomes and mean differences (with 95% CI) for continuous outcomes.

RESULTS

We included 18 RCTs with 19,300 participants. There was no significant difference in the risk of all-cause mortality and CV events between the groups (RR=1.01; 95%CI: 0.96-1.06; p=0.69). In 16 trials, insulin showed greater efficacy in glycaemic control (mean diff=-0.20; 95%CI: -0.28 to -0.11) but the proportion achieving HbA1c level of either ⩽7.0% or 7.4% (53 or 57mmol/mol) was similar in both (OR=1.55; 95%CI=0.92-2.62). The non-insulin group had a significant reduction in weight (mean diff=-3.41; 95%CI: -4.50 to -2.32) and an increase in the proportion of adverse events (54.7% vs 45.3%, p=0.044), but the insulin group showed an (RR=1.90; 95%CI: 1.44-2.51) increased risk of hypoglycaemia.

CONCLUSION

There was no difference in the risk of all-cause mortality and adverse cardiovascular (CV) events between Insulin and non-insulin GLTs. Insulin was associated with superior reduction in HbA1c; least reduction in weight and higher risk of hypoglycaemia. Both showed similar proportion of patients achieving HbA1c target. Non-insulin GLTs were associated with a higher risk in reported adverse drug events.

Glucose levels as a prognostic marker in patients with ST-segment elevation myocardial infarction: a case-control study

BACKGROUND

Patients with myocardial infarction (MI) have a high mortality. Therefore, new risk markers and predictors of an adverse outcome for MI are required. The role of hyperglycemia in the development of cardiovascular complications in MI patients is still unclear.

METHODS

A total of 529 consecutive patients with the diagnosis of ST-segment elevation acute coronary syndrome within 24 h of the onset of symptoms were included in the study. All of the patients underwent blood glucose measurement at admission to hospital. The glycemic profile, including measurement of blood glucose levels early in the night and in the morning (3 a.m. and 5 a.m.), was assessed in 77 patients with diabetes on days 6-10 of the course of MI to monitor the efficiency of blood glucose-lowering therapy and to detect hypoglycemic episodes.

RESULTS

In-hospital mortality showed relationship between the level of blood glucose on admission and in-hospital mortality in patients with MI with ST-segment elevation in combination with diabetes mellitus. There was a direct linear relationship between blood glucose levels and in-hospital mortality in patients without diabetes.

CONCLUSION

Episodes of hypoglycemia recorded in MI patients with diabetes in the hospital stage of treatment do not determine the prognosis, but enable identification of patients with an unfavorable course in the postinfarction period.

Hypoglycemia and risk of vascular events and mortality: a systematic review and meta-analysis

AIMS

Hypoglycemia has been associated with adverse outcomes in patients with diabetes and critical illness. However, such associations in these populations have not been systematically examined.

METHODS

We conducted a systematic review and meta-analysis of longitudinal follow-up cohort studies to investigate the associations between hypoglycemia and various adverse outcomes.

RESULTS

After removing duplicates and critically appraising all screened citations, a total of 19 eligible studies were included. As demonstrated by random-effects meta-analysis, hypoglycemia was strongly associated with a higher risk of adverse events (HR 1.90, 95 % CI 1.63-2.20; P < 0.001). Comparable risk ratios were shown in prespecified stratified analyses investigating above association for different study endpoints, in patients with or without critical illness, in patients with and without diabetes (from 1.47 to 3.31; p for interaction or heterogeneity >0.1). Additionally, a dose-dependent relationship between the severity of hypoglycemia and adverse vascular events and mortality (HR for mild hypoglycemia: 1.68, 95 % CI 1.25-2.26; P < 0.001 and HR for severe hypoglycemia: 2.33, 95 % CI 2.07-2.61; P < 0.001; p for trend 0.02) was observed. Suggested by a bias analysis, the above observations were unlikely to have resulted from unmeasured confounding parameters.

CONCLUSIONS

This is the first study demonstrating that hypoglycemia was associated with comparable risk ratios in different study populations and various study endpoints, and a trend of a dose-dependent relationship between hypoglycemia severity and adverse events. The findings of this systematic review support the speculation that hypoglycemia is a risk factor for adverse vascular events and mortality.

Association Between Glycosylated Hemoglobin Level and Cardiovascular Outcomes in Diabetic Patients After Percutaneous Coronary Intervention

Glycosylated hemoglobin (HbA1c) is a critical measure of glycemic control, which may be a reliable predictor of complications after percutaneous coronary intervention (PCI). This systematic review and meta-analysis evaluates the association between HbA1c levels and clinical outcomes in diabetic patients after PCI.Pubmed, Embase, and Cochrane Library databases (dated to December 2015) were screened for relevant studies. Appropriate diabetic cases and controls, assessed using blood HbA1c levels, were extracted, and statistical analysis was conducted using RevMan 5.3 software. Summary odds ratios (ORs) with 95% confidence intervals (CIs) were used to calculate the associations between HbA1c levels and clinical outcomes in diabetic patients after PCI. Ethics review and approval was not necessary because this systematic meta-analysis did not involve any direct human trials or animal experiments.Eight studies that reported HbA1c levels for a total of 3290 diabetic subjects after PCI were included in this meta-analysis. Comprehensive integration and analysis revealed a significant correlation between higher HbA1c levels and the risk of target vessel revascularization progression (OR 1.36, 95% CI 1.03-1.82) and nonfatal myocardial infarction after PCI (OR 2.47, 95% CI 1.38-4.44). However, no significant association was found between HbA1c levels and major adverse cardiovascular events (OR 1.02, 95% CI 0.83-1.27), all-cause mortality (OR 0.73, 95% CI 0.52-1.02), cardiac death (OR 1.12, 95% CI 0.62-2.03), or in-stent thrombosis (OR 0.65, 95% CI 0.23-1.87) among diabetic patients after PCI. Sensitivity analysis indicated a statistically robust result and revealed no publication bias.Our meta-analysis demonstrated that blood HbA1c levels might be associated with higher risks of target vessel revascularization progression and nonfatal myocardial infarction among diabetic patients after PCI. However, further studies with larger sample sizes are required to verify the association.

Low-dose intensive insulin therapy in patients with Acute Coronary Syndrome accompanied by Left Ventricular Failure: audit of two UK hospitals

AIMS AND OBJECTIVES

To determine whether a low-dose intravenous insulin regimen reduces blood glucose levels at a timely rate and associated side effects among patients with Acute Coronary Syndrome and Left Ventricular Failure.

BACKGROUND

Induced hypoglycaemia and the associated risks have questioned the benefits of intensive insulin therapy in patients presenting with raised blood glucose levels and Acute Coronary Syndromes. Local audit data identified that patients with Acute Coronary Syndrome and Left Ventricular Failure experienced more hypoglycaemic episodes than those with Acute Coronary Syndrome alone. Consequently, a new regimen of low-dose insulin for this group was implemented and audited over 12 months.

DESIGN

Audit.

METHODS

Thirty-six consecutive patient notes with a diagnosis of Acute Coronary Syndrome and blood glucose of ≥10 mmol/l treated with a new insulin therapy regimen were analysed. Data were extracted using a standardised form and entered into an Excel spreadsheet for analysis.

RESULTS

The mean age of the sample was 70 years with 66% of subjects being men and 50% presenting with Acute Coronary Syndrome and Left Ventricular Failure. The low-dose regimen was effective in achieving normoglycaemia, (range 4-8 mmol/l) for a consecutive six-hour period. This was achieved in 72% of patients and within a median time of 13 hours.

CONCLUSION

The audit suggests that a low-dose insulin regimen can effectively stabilise blood glucose in patients presenting with both Acute Coronary Syndrome and Left Ventricular Failure. The importance of regularly monitoring blood sugar levels is vital and highlights the role of nurses in minimising patient risk and promoting safety.

RELEVANCE TO PRACTICE

Nurses are instrumental in the safe implementation of intensive insulin guidelines. Close monitoring of patients is essential, enabling timely adjustments to treatments and ensuring patient safety. Regular audits allow nurses to evaluate care provision and continue to drive practice forward.