Diabetes of injury: novel insights

Effects of the stress hyperglycemia ratio on long-term mortality in patients with triple-vessel disease and acute coronary syndrome

AIMS

Risk assessment for triple-vessel disease (TVD) remain challenging. Stress hyperglycemia represents the regulation of glucose metabolism in response to stress, and stress hyperglycemia ratio (SHR) is recently found to reflect true acute hyperglycemic status. This study aimed to evaluate the prognostic value of SHR and its role in risk stratification in TVD patients with acute coronary syndrome (ACS).

METHODS

A total of 3812 TVD patients with ACS with available baseline SHR measurement were enrolled from two independent centers. The endpoint was cardiovascular mortality. Cox regression was used to evaluate the association between SHR and cardiovascular mortality. The SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) II (SSII) was used as the reference model in the model improvement analysis.

RESULTS

During a median follow-up of 5.1 years, 219 (5.8%) TVD patients with ACS suffered cardiovascular mortality. TVD patients with ACS with high SHR had an increased risk of cardiovascular mortality after robust adjustment for confounding (high vs. median SHR: adjusted hazard ratio 1.809, 95% confidence interval 1.160-2.822, P = 0.009), which was fitted as a J-shaped pattern. The prognostic value of the SHR was found exclusively among patients with diabetes instead of those without diabetes. Moreover, addition of SHR improved the reclassification abilities of the SSII model for predicting cardiovascular mortality in TVD patients with ACS.

CONCLUSIONS

The high level of SHR is associated with the long-term risk of cardiovascular mortality in TVD patients with ACS, and is confirmed to have incremental prediction value beyond standard SSII. Assessment of SHR may help to improve the risk stratification strategy in TVD patients who are under acute stress.

Stress hyperglycaemia following trauma - a survival benefit or an outcome detriment?

PURPOSE OF REVIEW

Stress hyperglycaemia occur often in critically injured patients. To gain new consideration about it, this review compile current as well as known immunological and biochemical findings about causes and emergence.

RECENT FINDINGS

Glucose is the preferred energy substrate for fending immune cells, reparative tissue and the cardiovascular system following trauma. To fulfil these energy needs, the liver is metabolically reprogrammed to rebuild glucose from lactate and glucogenic amino acids (hepatic insulin resistance) at the expenses of muscles mass and - to a less extent - fat tissue (proteolysis, lipolysis, peripheral insulin resistance). This inevitably leads to stress hyperglycaemia, which is evolutionary preserved and seems to be an essential and beneficial survival response. It is initiated by damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs), intensified by immune cells itself and mainly ruled by tumour necrosis factor (TNF)α and catecholamines with lactate and hypoxia inducible factor (HIF)-1α as intracellular signals and lactate as an energy shuttle. Important biochemical mechanisms involved in this response are the Warburg effect as an efficient metabolic shortcut and the extended Cori cycle.

SUMMARY

Stress hyperglycaemia is beneficial in an acute life-threatening situation, but further research is necessary, to prevent trauma patients from the detrimental effects of persisting hyperglycaemia.

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

Background

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

Methods

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

Results

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

Conclusions

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

Prevalence and prognostic impact of stress-induced hyperglycemia in patients with acute type A aortic dissection

AIMS

To explore the prevalence of stress-induced hyperglycemia (SIH) in acute type A aortic dissection (ATAAD) patients without diabetes, and its impact on short-term and long-term clinical outcomes.

METHODS

A total of 1098 patients with confirmed diagnosis of ATAAD were consecutively enrolled. According to the admission blood glucose (BG), patients were divided into the normoglycemia group (BG < 7.8 mmol/L), mild to moderate SIH group (7.8 ≤ BG < 11.1 mmol/L) and severe SIH group (BG ≥ 11.1 mmol/L). Multivariate regression analysis were used to explore the association between SIH and mortality risk.

RESULTS

There were 421 ATAAD patients (38.3%) with SIH, including 361 cases (32.9%) in the mild to moderate group and 60 cases (5.46%) in the severe group. The proportion of high-risk clinical manifestations and conservative treatment was greater in the SIH group than the normoglycemia group. Severe SIH was associated with high risk of 30-day (OR: 3.773, 95%CI: 1.004-14.189, P = 0.0494) and 1-year mortality risk (OR: 3.522 95%CI: 1.018-12.189, P = 0.0469).

CONCLUSIONS

Approximately 40% of the patients with ATAAD had SIH, and were more likely to present with high-risk clinical features and receive non-surgical treatment. Severe SIH could be used as an independent predictor of increased short-term and long-term mortality risk and reflect the disease severity of ATAAD.

Diabetic and stress-induced hyperglycemia in spontaneous intracerebral hemorrhage: A multicenter prospective cohort (CHEERY) study

INTRODUCTION

Admission hyperglycemia is a common finding after spontaneous intracerebral hemorrhage (ICH) secondary to pre-existing diabetes mellitus (DM) or stress-induced hyperglycemia (SIH). Studies of the causal relationship between SIH and ICH outcomes are rare.

AIM

We aimed to identify whether SIH or pre-existing DM was the cause of admission hyperglycemia associated with ICH outcomes.

METHODS

Admission glycosylated hemoglobin (HbA1c), glucose levels, and comorbidity data from the prospective, multicenter cohort, Chinese Cerebral Hemorrhage: Mechanisms and Intervention Study (CHEERY), were collected and analyzed. According to different admission blood glucose and HbA1c levels, patients were divided into nondiabetic normoglycemia (NDN), diabetic normoglycemia (DN), diabetic hyperglycemia (DH), and SIH groups. Modified Poisson regression models were used to analyze ICH outcomes in the different groups.

RESULTS

In total, 1372 patients were included: 388 patients with admission hyperglycemia, 239 with DH, and 149 with SIH. In patients with hyperglycemia, SIH was associated with a higher risk of pulmonary infection [risk ratios (RR): 1.477, 95% confidence interval (CI): 1.004-2.172], 30-day (RR: 1.068, 95% CI: 1.009-1.130) and 90-day mortality after ICH (RR: 1.060, 95% CI: 1.000-1.124).

CONCLUSIONS

Admission hyperglycemia is a common finding after ICH, and SIH is a sensitive predictor of the risk of pulmonary infection and all-cause death after ICH.

A review of stress-induced hyperglycaemia in the context of acute ischaemic stroke: Definition, underlying mechanisms, and the status of insulin therapy

The transient elevation of blood glucose produced following acute ischaemic stroke (AIS) has been described as stress-induced hyperglycaemia (SIH). SIH is common even in patients with AIS who have no previous diagnosis of diabetes mellitus. Elevated blood glucose levels during admission and hospitalization are strongly associated with enlarged infarct size and adverse prognosis in AIS patients. However, insulin-intensive glucose control therapy defined by admission blood glucose for SIH has not achieved the desired results, and new treatment ideas are urgently required. First, we explore the various definitions of SIH in the context of AIS and their predictive value in adverse outcomes. Then, we briefly discuss the mechanisms by which SIH arises, describing the dual effects of elevated glucose levels on the central nervous system. Finally, although preclinical studies support lowering blood glucose levels using insulin, the clinical outcomes of intensive glucose control are not promising. We discuss the reasons for this phenomenon.

Association of the stress hyperglycemia ratio and clinical outcomes in patients with stroke: A systematic review and meta-analysis

Objective

Stress hyperglycemia (SH) is common in patients with acute diseases, such as stroke and myocardial infarction. Stress hyperglycemia ratio (SHR) is calculated by glucose/glycated hemoglobin and has been widely used for evaluating SH. But whether SHR is associated with clinical outcomes in stroke patients remains unclear so far. Although many studies have shown that higher SHR means poor outcomes, there is still no absolute evidence that SHR plays a critical role in stroke patients. Hence, we performed a systematic review and meta-analysis aiming to investigate the association between SHR and clinical outcomes in stroke patients.

Methods

We performed a comprehensive literature search of the PubMed, Embase, Cochrane Library databases, Clinicaltrials.gov, and WHO-ICTRP. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we performed our study. The Newcastle-Ottawa Scale (NOS) tool was used to examine the potential bias of included studies. The endpoints including poor outcome, mortality, neurological deficit, hemorrhagic transformation (HT), and infectious complications were statistically analyzed.

Results

Sixteen retrospective studies met the eligibility criteria, and a number of 183,588 patients were included. Our meta-analysis demonstrated a significant increase in the incidence of poor outcome, according to assessment by the modified Rankin Scale (mRS) ≥ 3 points [odds ratio (OR) 2.53, 95% confidence interval (CI) 1.99–3.22, P < 0.00001, I² = 68%], mortality (OR 1.96, 95% CI 1.58–2.44, P < 0.00001, I² = 61%), neurological deficit (OR 1.99, 95% CI 1.47–2.70, P < 0.00001, I² = 75%), hemorrhagic transformation (HT) (OR 3.70, 95% CI 2.69–5.08, P < 0.00001, I² = 0%), and infectious complications [(Pneumonia) OR 2.06, 95% CI 1.57–2.72, P < 0.00001, I² = 24%; (Urinary tract infection) OR 2.53, 95% CI 1.45–4.42, P = 0.001, I² = 57%] in stroke patients with higher SHR. However, no significant influence was observed for recanalization rate (OR 0.86, 95% CI 0.54–1.38, P = 0.53, I² = 0%).

Conclusion

With or without diabetes, no matter whether undergoing intravenous thrombolysis or mechanical thrombectomy, higher SHR significantly increased the occurrence of poor outcomes, mortality, neurological deficit, HT, and infectious complications. The recanalization rate was not statistically significant between the two groups. More attention must be paid in clinical practice to SH. Future investigation should focus on the diagnostic value of SHR and the early control of hyperglycemia. Meanwhile, whether SHR could become a novel and promising target for early intervention is worthy of attention in further research. Besides, the influence of the dynamic change of glucose-to-HbA1c ratio, namely SHR, on intracerebral hemorrhage outcomes requires further investigation in future research. Although no randomized double-blind studies have been conducted, the available massive sample studies reflect the actual situation in the clinic and assist clinical decision makers.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022345587.

Impact of Stress Hyperglycemia on Early Neurological Deterioration in Acute Ischemic Stroke Patients Treated With Intravenous Thrombolysis

Background and Purpose

It has been widely reported that stress hyperglycemia contributes to poor prognosis in patients experiencing acute ischemic stroke (AIS). However, its predictive value for early neurological deterioration (END) after intravenous administration of recombinant tissue-type plasminogen activator (IV-rtPA) in AIS patients is still unclear. The aim of this study was to evaluate the impact of stress hyperglycemia on the risk of END after IV-rtPA.

Methods

A total of 798 consecutive patients treated with IV-rtPA were included in this study. The stress hyperglycemia ratio (SHR) was calculated as fasting plasma glucose level at admission (mg/dl)/glycosylated hemoglobin (HbAlc) (%). END was defined as a National Institutes of Health Stroke Scale Score (NIHSS) ≥ 4 points 24 h after IV-rtPA, and poor functional outcome at discharge was defined as a modified Rankin Scale (mRS) score of 3–6 at discharge. Patients with a prior history of diabetes or HbAlc ≥ 6.5% were considered to have diabetes mellitus. Patients were grouped according to SHR values. Multivariate logistical regression was used to evaluate the risk of END for patients within specific SHR categories.

Results

In total, 139 (17.4%) patients had END. After adjusting for confounders, the highest tertile group had higher risks of END and poor functional outcome at discharge than those of patients in the lowest tertile group (OR, 1.95; 95% CI, 1.21–3.15; p = 0.006) (OR, 1.85; 95% CI, 1.163–2.941; p = 0.009), and the predictive value of high SHR for END was also significant in patients with diabetes mellitus (OR, 3.05; 95% CI, 1.29–7.21; p = 0.011). However, a significant association of high SHR and poor functional outcome was only found in patients without diabetes (OR, 1.85; 95% CI, 1.002–3.399; p = 0.045).

Conclusion

A higher SHR predicted that patients with severe stress hyperglycemia had higher risks of END and poor functional outcome at discharge after IV-rtPA.

Stress Hyperglycemia, Diabetes Mellitus and COVID-19 Infection: Risk Factors, Clinical Outcomes and Post-Discharge Implications

The novel severe acute respiratory distress syndrome-coronavirus 2 (SARS-CoV-2) has caused one of the most substantial pandemics that has affected humanity in the last century. At the time of the preparation of this review, it has caused the death of around 5 million people around the globe. There is ample evidence linking higher mortality risk rates from Coronavirus disease-19 (COVID-19) with male gender, advancing age and comorbidities, such as obesity, arterial hypertension, cardiovascular disease, chronic obstructive pulmonary disease, diabetes mellitus, and cancer. Hyperglycemia has been found to be accompanying COVID-19 not only in individuals with overt diabetes. Many authors claim that blood glucose levels should also be monitored in non-diabetic patients; moreover, it has been confirmed that hyperglycemia worsens the prognosis even without pre-existing diabetes. The pathophysiological mechanisms behind this phenomenon are complex, remain controversial, and are poorly understood. Hyperglycemia in the setting of COVID-19 could be a consequence of deterioration in pre-existing diabetes, new-onset diabetes, stress-induced or iatrogenic due to substantial usage of corticosteroids within the context of a severe COVID-19 infection. It is also plausible that it might be a result of adipose tissue dysfunction and insulin resistance. Last but not least, SARS-CoV-2 is also claimed to trigger sporadically direct β-cell destruction and β-cell autoimmunity. Pending further validations with longitudinal data are needed to legitimize COVID-19 as a potential risk factor for the development of diabetes. Hereby, we present an emphasized critical review of the available clinical data in an attempt to unravel the complex mechanisms behind hyperglycemia in COVID-19 infection. The secondary endpoint was to evaluate the bidirectional relationship between COVID-19 and diabetes mellitus. As the worldwide pandemic is still expanding, demand for answering these questions is arising. It will be of immense help for the management of COVID-19 patients, as well as for the implementation of post-discharge policies for patients with a high risk of developing diabetes.

Stress Induced Hyperglycemia in the Context of Acute Coronary Syndrome: Definitions, Interventions, and Underlying Mechanisms

Elevation of glucose level in response to acute coronary syndrome (ACS) has been recognized as stress induced hyperglycemia (SIH). Plenty of clinical studies have documented that SIH occurs very common in patients hospitalized with ACS, even in those without previously known diabetes mellitus. The association between elevated blood glucose levels with adverse outcome in the ACS setting is well-established. Yet, the precise definition of SIH in the context of ACS remains controversial, bringing confusions about clinical management strategy. Several randomized trials aimed to evaluate the effect of insulin-based therapy on outcomes of ACS patients failed to demonstrate a consistent benefit of intensive glucose control. Mechanisms underlying detrimental effects of SIH on patients with ACS are undetermined, oxidative stress might play an important role in the upstream pathways leading to subsequent harmful effects on cardiovascular system. This review aims to discuss various definitions of SIH and their values in predicting adverse outcome in the context of ACS, as well as the effect of intensive glucose control on clinical outcome. Finally, a glimpse of the underlying mechanisms is briefly discussed.

Stress hyperglycemia, cardiac glucotoxicity, and critically ill patient outcomes current clinical and pathophysiological evidence

Stress hyperglycemia is a transient increase in blood glucose during acute physiological stress in the absence of glucose homeostasis dysfunction. Its's presence has been described in critically ill patients who are subject to many physiological insults. In this regard, hyperglycemia and impaired glucose tolerance are also frequent in patients who are admitted to the intensive care unit for heart failure and cardiogenic shock. The hyperglycemia observed at the beginning of these cardiac disorders appears to be related to a variety of stress mechanisms. The release of major stress and steroid hormones, catecholamine overload, and glucagon all participate in generating a state of insulin resistance with increased hepatic glucose output and glycogen breakdown. In fact, the observed pathophysiological response, which appears to regulate a stress situation, is harmful because it induces mitochondrial impairment, oxidative stress-related injury to cells, endothelial damage, and dysfunction of several cellular channels. Paradigms are now being challenged by growing evidence of a phenomenon called glucotoxicity, providing an explanation for the benefits of lowering glucose levels with insulin therapy in these patients. In the present review, the authors present the data published on cardiac glucotoxicity and discuss the benefits of lowering plasma glucose to improve heart function and to positively affect the course of critical illness.

Prognostic Value of Admission Blood Glucose Level in Critically Ill Patients Admitted to Cardiac Intensive Care Unit according to the Presence or Absence of Diabetes Mellitus

BACKGROUND

Admission blood glucose (BG) level is a predictor of mortality in critically ill patients with various conditions. However, limited data are available regarding this relationship in critically ill patients with cardiovascular diseases according to diabetic status.

METHODS

A total of 1,780 patients (595 with diabetes) who were admitted to cardiac intensive care unit (CICU) were enrolled from a single center registry. Admission BG level was defined as maximal serum glucose level within 24 hours of admission. Patients were divided by admission BG level: group 1 (< 7.8 mmol/L), group 2 (7.8-10.9 mmol/L), group 3 (11.0-16.5 mmol/L), and group 4 (≥ 16.6 mmol/L).

RESULTS

A total of 105 patients died in CICU (62 non-diabetic patients [5.2%] and 43 diabetic patients [7.9%]; P = 0.105). The CICU mortality rate increased with admission BG level (1.7%, 4.8%, 10.3%, and 18.8% from group 1 to group 4, respectively; P < 0.001). On multivariable analysis, hypertension, mechanical ventilator, continuous renal replacement therapy, acute physiology and chronic health evaluation II (APACHE II) score, and admission BG level significantly influenced CICU mortality in non-diabetic patients (group 1 vs. group 3: hazard ratio [HR], 3.31; 95% confidence interval [CI], 1.47-7.44; P = 0.004; group 1 vs. group 4: HR, 6.56; 95% CI, 2.76-15.58; P < 0.001). However, in diabetic patients, continuous renal replacement therapy and APACHE II score influenced CICU mortality but not admission BG level.

CONCLUSION

Admission BG level was associated with increased CICU mortality in critically ill, non-diabetic patients admitted to CICU but not in diabetic patients.

Risk Factors of Intraoperative Dysglycemia in Elderly Surgical Patients

BACKGROUNDː Dysglycemia is associated with adverse outcome including increased morbidity and mortality in surgical patients. Acute insulin resistance due to the surgical stress response is seen as a major cause of so-called stress hyperglycemia. However, understanding of factors determining blood glucose (BG) during surgery is limited. Therefore, we investigated risk factors contributing to intraoperative dysglycemia. METHODSː In this subgroup investigation of the BIOCOG study, we analyzed 87 patients of ≥ 65 years with tight intraoperative BG measurement every 20 min during elective surgery. Dysglycemia was defined as at least one intraoperative BG measurement outside the recommended target range of 80-150 mg/dL. Additionally, all postoperative BG measurements in the ICU were obtained. Multivariable logistic regression analysis adjusted for age, sex, American Society of Anesthesiologists (ASA) status, diabetes, type and duration of surgery, minimum Hemoglobin (Hb) and mean intraoperative norepinephrine use was performed to identify risk factors of intraoperative dysglycemia. RESULTSː 46 (52.9%) out of 87 patients developed intraoperative dysglycemia. 31.8% of all intraoperative BG measurements were detected outside the target range. Diabetes [OR 9.263 (95% CI 2.492, 34.433); p=0.001] and duration of surgery [OR 1.005 (1.000, 1.010); p=0.036] were independently associated with the development of intraoperative dysglycemia. Patients who experienced intraoperative dysglycemia had significantly elevated postoperative mean (p<0.001) and maximum BG levels (p=0.001). Length of ICU (p=0.007) as well as hospital stay (p=0.012) were longer in patients with dysglycemia. CONCLUSIONSː Diabetes and duration of surgery were confirmed as independent risk factors for intraoperative dysglycemia, which was associated with adverse outcome. These patients, therefore, might require intensified glycemic control. Increased awareness and management of intraoperative dysglycemia is warranted.

Perioperative insulin therapy

Surgical patients commonly develop hyperglycemia secondary to the neuroendocrine stress response. Insulin treatment of hyperglycemia is required to overcome the perioperative catabolic state and acute insulin resistance. Besides its metabolic actions on glucose metabolism, insulin also displays nonmetabolic physiological effects. Preoperative glycemic assessment, maintenance of normoglycemia, and avoidance of glucose variability are paramount to optimize surgical outcomes. This review discusses the basic physiology and effects of insulin as well as practical issues pertaining to its management during the perioperative period.

Diabetes and the Association of Postoperative Hyperglycemia With Clinical and Economic Outcomes in Cardiac Surgery

OBJECTIVE

The management of postoperative hyperglycemia is controversial and generally does not take into account pre-existing diabetes. We analyzed clinical and economic outcomes associated with postoperative hyperglycemia in cardiac surgery patients, stratifying by diabetes status.

RESEARCH DESIGN AND METHODS

Multicenter cohort study in 4,316 cardiac surgery patients operated on in 2010. Glucose was measured at 6-h intervals for 48 h postoperatively. Outcomes included cost, hospital length of stay (LOS), cardiac and respiratory complications, major infections, and death. Associations between maximum glucose levels and outcomes were assessed with multivariable regression and recycled prediction analyses.

RESULTS

In patients without diabetes, increasing glucose levels were associated with a gradual worsening of outcomes. In these patients, hyperglycemia (≥180 mg/dL) was associated with an additional cost of $3,192 (95% CI 1,972 to 4,456), an additional hospital LOS of 0.8 days (0.4 to 1.3), an increase in infections of 1.6% (0.5 to 2.8), and an increase in respiratory complications of 2.6% (0.0 to 5.3). However, among patients with insulin-treated diabetes, optimal outcomes were associated with glucose levels considered to be hyperglycemic (180 to 240 mg/dL). This level of hyperglycemia was associated with cost reductions of $6,225 (-12,886 to -222), hospital LOS reductions of 1.6 days (-3.7 to 0.4), infection reductions of 4.1% (-9.1 to 0.0), and reductions in respiratory complication of 12.5% (-22.4 to -3.0). In patients with non-insulin-treated diabetes, outcomes did not differ significantly when hyperglycemia was present.

CONCLUSIONS

Glucose levels <180 mg/dL are associated with better outcomes in most patients, but worse outcomes in patients with diabetes with a history of prior insulin use. These findings support further investigation of a stratified approach to the management of patients with stress-induced postoperative hyperglycemia based on prior diabetes status.

Glucose as a risk predictor in acute medical emergency admissions

AIMS

The aims of this study were to examine the relationship between admission blood glucose and mortality in a large, unselected cohort of acutely ill medical patients and to assess the impact of diabetes on this relationship.

METHODS

We studied the broad pattern of acute medical admissions over an eight year period and the impact of admission serum glucose on in-hospital mortality. Significant predictors of outcome, including acute illness severity and co-morbidity, were entered into a multivariate regression model, adjusting the univariate estimates of the glycaemic status on mortality.

RESULTS

There were 45,068 consecutive acute medical emergency admissions between 2005 and 2012. The normoglycaemic (>4.0 ≤7.0 mmol/l) cohort (86%) had a 3.9% in-hospital mortality. Both hypoglycaemia (OR: 3.23: 95% CI: 2.59-4.04; p<0.001) and hyperglycaemia (OR: 2.1; 95% CI: 1.9-2.4; p<0.001) predicted an increased risk of an in-hospital death. Neither of these increased risks were fully adjusted nor explained by a highly predictive outcome model, using multiple acute illness parameters. Hyperglycaemia did not carry similar adverse prognostic implications for patients with diabetes.

CONCLUSION

In patients without diabetes, an abnormal serum glucose is independently predictive of an increased mortality among the broad cohort of acute emergency medical patients. Similar disturbances of glucose homeostasis for patients with diabetes do not confer equivalent adverse prognostic implications.

Renal cell apoptosis and new treatment options in sepsis-induced acute kidney injury

Sepsis is a common and important cause of mortality in critically ill patients. Acute kidney injury (AKI) is one of the most important factors determining morbidity and mortality in the prognosis of sepsis. Recent studies have indicated that the pathogenetic mechanism in septic AKI is totally different from that in non-septic AKI. Our understanding of sepsis-associated AKI pathophysiology is shifting from renal vasoconstriction, ischemia, and acute tubular necrosis to heterogeneous vasodilation, hyperemia, and acute tubular apoptosis. Especially, apoptosis is gradually gaining importance in the understanding of the development of renal injury. The frequency of renal tubular apoptosis on biopsies of septic patients has been pointed out in recently published studies. Apoptosis can be triggered by ischemia, exogen toxins, or endogen mediators. It has been shown in some animal models that hyperglycemia, which is common in critically ill patients, causes apoptosis in renal tubular cells. New treatment options have emerged in the light of recent findings. Ghrelin that inhibits pro-inflammatory cytokines, caspase inhibitors that block the apoptotic pathway, and suppression of anti-inflammatory reactions are under study. Among the existing methods of treatment, usage of arginine, which is a vasopressor agent, ventilation with a low tidal volume, and hemofiltration methods cleaning toxic mediators from the circulation should be considered in the first place. Hyperglycemia treatment is of major importance, since, besides its anti-inflammatory effect, it has a protective role on the kidney. Regarding pathogenesis, rates of morbidity and mortality are aimed to be reduced through the new agents of therapy that have been studied on.

Glycemic variability and glycemic control in the acutely ill cardiac patient

The mechanisms for hyperglycemia-mediated harm in the hospitalized cardiac patient are poorly understood. Potential obstacles in the inpatient management of hyperglycemia in cardiac patients include rapidly changing clinical status, frequent procedures and interruptions in carbohydrate exposure, and short hospital length of stay. A patient's preadmission regimen is rarely suitable for inpatient glycemic control. Instead, an approach to a flexible, physiologic insulin regimen is described, which is intended to minimize glycemic excursions. When diabetes or hyperglycemia is addressed early and consistently, the hospital stay can serve as a potential window of opportunity for reinforcing self-care behaviors that reduce long-term complications.

Serum glucose levels for predicting death in patients admitted to hospital for community acquired pneumonia: prospective cohort study

OBJECTIVE

To examine whether acute dysglycaemia predicts death in people admitted to hospital with community acquired pneumonia.

DESIGN

Multicentre prospective cohort study.

SETTING

Hospitals and private practices in Germany, Switzerland, and Austria.

PARTICIPANTS

6891 patients with community acquired pneumonia included in the German community acquired pneumonia competence network (CAPNETZ) study between 2003 and 2009.

MAIN OUTCOME MEASURES

Univariable and multivariable hazard ratios adjusted for sex, age, current smoking status, severity of community acquired pneumonia using the CRB-65 score (confusion, respiratory rate >30/min, systolic blood pressure ≤ 90 mm Hg or diastolic blood pressure ≤ 60 mm Hg, and age ≥ 65 years), and various comorbidities for death at 28, 90, and 180 days according to serum glucose levels on admission.

RESULTS

An increased serum glucose level at admission to hospital in participants with community acquired pneumonia and no pre-existing diabetes was a predictor of death at 28 and 90 days. Compared with participants with normal serum glucose levels on admission, those with mild acute hyperglycaemia (serum glucose concentration 6-10.99 mmol/L) had a significantly increased risk of death at 90 days (1.56, 95% confidence interval 1.22 to 2.01; P<0.001), and this risk increased to 2.37 (1.62 to 3.46; P<0.001) when serum glucose concentrations were ≥ 14 mmol/L. In sensitivity analyses the predictive value of serum glucose levels on admission for death was confirmed at 28 days and 90 days. Patients with pre-existing diabetes had a significantly increased overall mortality compared with those without diabetes (crude hazard ratio 2.47, 95% confidence interval 2.05 to 2.98; P<0.001). This outcome was not significantly affected by serum glucose levels on admission (P = 0.18 for interaction).

CONCLUSIONS

Serum glucose levels on admission to hospital can predict death in patients with community acquired pneumonia without pre-existing diabetes. Acute hyperglycaemia may therefore identify patients in need of intensified care to reduce the risk of death from community acquired pneumonia.

[Effectiveness and safety of goal directed nurse-led blood glucose control in an intensive care unit: a prospective observational study]

OBJECTIVE

to evaluate the effectiveness and safety of a nurse-led blood glucose control protocol in a medical ICU.

METHOD

a descriptive, prospective study was carried out for a period of 13 months. All blood glucose values from patients on insulin therapy for intensive glycemic control were recorded daily.

RESULTS

A total of 12,677 blood glucose determinations were performed on the 69 patients under glycemic control; 57.9% of the determinations had predetermined study target values for blood glucose (100-140 mg/dl) and 68.8% of the determinations had physiological blood glucose values (80-140 mg/dl); no values under 40 mg/dl were obtained, and only 0.2% were between 40-60 mg/dl.

CONCLUSIONS

For an adequate blood glucose control using intensive insulin therapy, individual management of insulin infusion regimen is essential, adjusted to the characteristics of each patient. A nurse-led intervention has allowed better results to be obtained in comparison with other studies in which different protocols for insulin infusion are used.

Hypoglycemia in the hospital

Hypoglycemia is a common adverse event affecting hospitalized patients with diabetes. This paper reviews the data regarding optimization of glucose in hospitalized patients, discusses the scope and significance of hypoglycemia in the hospital, and makes recommendations on how to reduce the risk of this serious adverse event.

Acute glucose elevation is highly predictive of infection and outcome in critically injured trauma patients

OBJECTIVE(S)

To evaluate whether acute glucose elevation (AGE) is predictive of infection and outcome in critically injured trauma patients during the first 14 days of ICU admission.

METHODS

A prospective study was conducted on 2200 patients admitted to the ICU over a 2 1/2 year period. The diagnosis of infection was made via a multidisciplinary fashion utilizing CDC criteria. After early glucose stabilization occurred (no significant change for 48 hours after admission) monitoring for AGE was performed utilizing a computational and graded algorithmic model. Iatrogenic causes of AGE were excluded. Stepwise regression models were performed controlling for age, gender, mechanism of injury, diabetes, injury severity, and APACHE 2 score. ROC curves were used to evaluate the positive predictive value of the test.

RESULTS

Seventy-seven percent of the patients in the cohort were males, and were admitted for blunt injuries (n = 1870 or 85%). The mean age, Injury Severity Score, and APACHE score were 44 ± 20 years, 29 ± 13, and 13 ± 7, respectively. The mean admission serum glucose value was 141 ± 36 mg/dL (range, 64-418 mg/dL). A total of 616 (28%) patients were diagnosed with an infection during the first 14 days of admission. AGE had a 91% positive predictive value for infection diagnosis. In addition, AGE was associated with a significant increase in ventilator, ICU, and hospital days as well as mortality even when adjusted for age, injury severity, APACHE score, and diabetes (P < 0.001).

CONCLUSIONS

AGE is a highly accurate predictor of infection and should stimulate clinicians to identify a new source of infection.

Glycemic control in the medical intensive care unit

Hyperglycemia in the critically ill is a well-known phenomenon, even in those without known diabetes. The stress response is due to a complex interplay between counter-regulatory hormones, cytokines, and changes in insulin sensitivity. Illness/infection, overfeeding, medications (e.g., corticosteroids), insufficient insulin, and/or volume depletion can be additional contributors. Acute hyperglycemia can adversely affect fluid balance (through glycosuria and dehydration), immune and endothelial function, inflammation, and outcome. While there are several insulin infusion protocols that are able to safely and effectively treat hyperglycemia, the bulk of accumulated evidence does not support a causal relationship between acute hyperglycemia and adverse outcomes in the medical intensive care unit. Meta-analysis of randomized controlled trials suggests there is no benefit to tightening glucose control to normal levels compared to a reasonable and achievable goal of 140 to 180 mg/dl. There is a significantly increased risk of hypoglycemia. Although there is some evidence that patients without known diabetes have worse outcomes than those with known diabetes, more recent evidence is conflicting. Glycemic control in critically ill patients should not be neglected, as studies have not tested tight versus no/poor control, but tight versus good control. A moderate approach to managing critical illness hyperglycemia seems most prudent at this juncture. Future research should ascertain whether there are certain subgroups of patients that would benefit from tighter glycemic goals. It also remains to be seen if tight glucose control is beneficial once hypoglycemia is minimized with technological advances such as continuous glucose monitoring systems.

Stress hyperglycaemia

Results of randomised controlled trials of tight glycaemic control in hospital inpatients might vary with population and disease state. Individualised therapy for different hospital inpatient populations and identification of patients at risk of hyperglycaemia might be needed. One risk factor that has received much attention is the presence of pre-existing diabetes. So-called stress hyperglycaemia is usually defined as hyperglycaemia resolving spontaneously after dissipation of acute illness. The term generally refers to patients without known diabetes, although patients with diabetes might also develop stress hyperglycaemia-a fact overlooked in many studies comparing hospital inpatients with or without diabetes. Investigators of several studies have suggested that patients with stress hyperglycaemia are at higher risk of adverse consequences than are those with pre-existing diabetes. We describe classification of stress hyperglycaemia, mechanisms of harm, and management strategies.

Glycaemic control and perioperative organ protection

The concept of stress hyperglycaemia as an adaptive, beneficial response in critical illness has recently been challenged. Two large prospective randomized controlled trials in the Leuven University Hospital surgical and medical ICUs demonstrated that maintenance of normoglycaemia with intensive insulin therapy substantially prevents morbidity and reduces mortality. Strict normoglycaemia is required to gain most clinical benefit. With this therapy the risk of hypoglycaemia increased, but without inducing obvious clinical sequellae. Other studies have been used to advocate against implementation of intensive insulin therapy by showing lack of benefit or questioning safety. However, these studies are inconclusive on this subject, due to problems of not reaching normal glucose levels clearly separated from the standard glycaemic group or lack of statistical power. Clearly, future studies should be adequately powered and comply with the study protocol in order to confirm the survival and other clinical benefits of intensive insulin therapy.

Glycemic penalty index for adequately assessing and comparing different blood glucose control algorithms

Introduction

Blood glucose (BG) control performed by intensive care unit (ICU) nurses is becoming standard practice for critically ill patients. New (semi-automated) 'BG control' algorithms (or 'insulin titration' algorithms) are under development, but these require stringent validation before they can replace the currently used algorithms. Existing methods for objectively comparing different insulin titration algorithms show weaknesses. In the current study, a new approach for appropriately assessing the adequacy of different algorithms is proposed.

Methods

Two ICU patient populations (with different baseline characteristics) were studied, both treated with a similar 'nurse-driven' insulin titration algorithm targeting BG levels of 80 to 110 mg/dl. A new method for objectively evaluating BG deviations from normoglycemia was founded on a smooth penalty function. Next, the performance of this new evaluation tool was compared with the current standard assessment methods, on an individual as well as a population basis. Finally, the impact of four selected parameters (the average BG sampling frequency, the duration of algorithm application, the severity of disease, and the type of illness) on the performance of an insulin titration algorithm was determined by multiple regression analysis.

Results

The glycemic penalty index (GPI) was proposed as a tool for assessing the overall glycemic control behavior in ICU patients. The GPI of a patient is the average of all penalties that are individually assigned to each measured BG value based on the optimized smooth penalty function. The computation of this index returns a number between 0 (no penalty) and 100 (the highest penalty). For some patients, the assessment of the BG control behavior using the traditional standard evaluation methods was different from the evaluation with GPI. Two parameters were found to have a significant impact on GPI: the BG sampling frequency and the duration of algorithm application. A higher BG sampling frequency and a longer algorithm application duration resulted in an apparently better performance, as indicated by a lower GPI.

Conclusion

The GPI is an alternative method for evaluating the performance of BG control algorithms. The blood glucose sampling frequency and the duration of algorithm application should be similar when comparing algorithms.

Tight blood glucose control: What is the evidence?

In two large, randomized studies, maintenance of normoglycemia with intensive insulin therapy largely prevented morbidity and reduced mortality of critically ill patients. Recently, questions have been raised about the efficacy and safety of this therapy. These issues are systematically addressed and discussed with the evidence available from these and other studies. The available studies show that an absolute reduction in risk of hospital death of 3% to 4% is to be expected from intensive insulin therapy in an intention-to-treat analysis. Future studies designed to confirm a statistically significant survival benefit should be adequately powered, with inclusion of >or=5,000 patients. When patients are treated with intensive insulin therapy for >3 days, the absolute reduction in the risk of death increases to approximately 8%. Insulin therapy also improves morbidity, more so when continued for >3 days. Strict blood glucose control to normoglycemia (<110 mg/dL) is required to obtain the most clinical benefit, but this inherently increases the risk of hypoglycemia. It remains unclear whether short hypoglycemic episodes are truly harmful for these patients. In conclusion, demonstration of the clinical benefits of intensive insulin therapy depends on the quality of blood glucose control and the statistical power of the studies.

Tight blood glucose control with insulin in the ICU: facts and controversies

Recently, the concept that stress hyperglycemia in critically ill patients is an adaptive, beneficial response has been challenged. Two large randomized studies demonstrated that maintenance of normoglycemia with intensive insulin therapy substantially prevents morbidity and reduces mortality in these patients. Since then, questions have been raised about the efficacy in general and in specific subgroups, and about the safety of this therapy with regard to potential harm of brief hypoglycemic episodes and of high-dose insulin administration. These issues are systematically addressed in relation to the available evidence. Intensive insulin therapy during intensive care is effective in reducing the mortality and morbidity of critical illness. The available randomized studies show that an absolute reduction in risk of hospital death of 3 to 4% is to be expected from this therapy in an intention-to-treat analysis. In order to confirm this survival benefit and assign it as statistically significant, future studies should be adequately powered, and hence sample size should be at least 5,000. The absolute reduction in the risk of death increases to approximately 8% when patients are treated with intensive insulin for at least 3 days. Data available thus far indicate that blood glucose control to strict normoglycemia is required to obtain the most clinical benefit. The risk of hypoglycemia increases with this therapy, but it remains unclear whether this is truly harmful in the setting of critical care.