Prognostic implication of hyperglycemia in myocardial infarction and primary angioplasty

Stress hyperglycemia and poor outcomes in patients with ST-elevation myocardial infarction: a systematic review and meta-analysis

Background

Hyperglycemia, characterized by elevated blood glucose levels, is frequently observed in patients with acute coronary syndrome, including ST-elevation myocardial infarction (STEMI). There are conflicting sources regarding the relationship between hyperglycemia and outcomes in STEMI patients. We aimed to compile evidence to assess the association between hyperglycemia and adverse outcomes.

Methods

We conducted a comprehensive search for articles on PubMed and Embase using search strategies which yielded 4,061 articles. After full-text screening, 66 articles were included for systematic review, and 62 articles were further selected for meta-analysis.

Results

The 66 included articles spanned the years 2005-2023. Of these, 45 articles reported admission blood glucose, 13 articles used HbA1c, and 7 articles studied fasting blood glucose. Most studies defined STEMI with primary PCI as their inclusion criteria. Mortality was the most often outcome reported related to hyperglycemia. Overall, 55 (83.3%) studies were at low risk of bias. Both admission and fasting blood glucose were significantly related to short- and long-term mortality after STEMI, with a pooled risk ratio (RR) of 3.02 (95%CI: 2.65-3.45) and 4.47 (95% CI: 2.54-7.87), respectively. HbA1c showed substantial association with long-term mortality (HR 1.69, 95% CI: 1.31-2.18)) with a pooled RR of 1.58 (95% CI 1.26-1.97). In subsequent analyses, admission hyperglycemia was associated with an increased risk of reinfarction (pooled RR 1.69, 95% CI 1.31-2.17), heart failure (pooled RR 1.56, 95% CI: 1.37-1.77), cardiogenic shock (pooled RR 3.68, 95% CI 2.65-5.11), repeat PCI or stent thrombosis (pooled RR 1.99, 95% CI 1.21-3.28), and composite major adverse cardiac and cerebrovascular events (MACCE) (pooled RR 1.99, 95% CI: 1.54-2.58).

Conclusions

Our study demonstrated that hyperglycemia has a strong association with poor outcomes after STEMI. Admission and fasting blood glucose are predictors for short-term outcomes, while HbA1c is more appropriate for predicting longer-term outcomes in STEMI patients.

Systematic Review Registration

PROSPERO 2021 (CRD42021292985).

Association of admission hyperglycemia and all-cause mortality in acute myocardial infarction with percutaneous coronary intervention: A dose–response meta-analysis

Objective

The aim of this study is to evaluate the associations between admission hyperglycemia and the risk of all-cause mortality in patients with acute myocardial infarction (AMI) with or without diabetes, to find optimal admission glucose intervention cut-offs, and to clarify the shape of the dose–response relations.

Methods

Medline/PubMed and EMBASE were searched from inception to 1 April 2022. Cohort studies reporting estimates of all-cause mortality risk in patients with admission hyperglycemia with AMI were included. The outcomes of interest include mortality and major adverse cardiac events (MACEs). A random effect dose–response meta-analysis was conducted to access linear trend estimations. A one-stage linear mixed effect meta-analysis was used for estimating dose–response curves. Relative risks and 95% confidence intervals were pooled using a random-effects model.

Results

Of 1,222 studies screened, 47 full texts were fully reviewed for eligibility. The final analyses consisted of 23 cohort studies with 47,177 participants. In short-term follow-up, admission hyperglycemia was associated with an increased risk of all-cause mortality (relative risk: 3.12, 95% confidence interval 2.42–4.02) and MACEs (2.34, 1.77–3.09). In long-term follow-up, admission hyperglycemia was associated with an increased risk of all-cause mortality (1.97, 1.61–2.41) and MACEs (1.95, 1.21–3.14). A linear dose–response association was found between admission hyperglycemia and the risk of all-cause mortality in patients with or without diabetes.

Conclusion

Admission hyperglycemia was significantly associated with higher all-cause mortality risk and rates of MACEs. However, the association between admission hyperglycemia and long-term mortality risk needs to be determined with caution. Compared with current guidelines recommendations, a lower intervention cut-off and more stringent targets for admission hyperglycemia may be appropriate.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022317280], identifier [CRD42022317280].

Chronic activation of cardiac Atg-5 and pancreatic Atg-7 by intermittent fasting alleviates acute myocardial infarction in old rats

BACKGROUND

Aging is associated with cardiovascular and metabolic changes, increasing the susceptibility to acute myocardial infarction (AMI). Intermittent fasting (IF) has a beneficial effect on the age-associated cardiovascular diseases. The present study was planned to investigate the possible protective effect of IF against acute AMI induced by isoproterenol (ISO) in old rats and its possible underlying mechanisms mediated by heart and pancreatic autophagy. Thirty Male Wistar rats were divided into four groups: adult; old; Old-ISO (rats subjected to AMI by ISO) and Old-F-ISO groups (rats were subjected to IF for 4 weeks and AMI by ISO).

RESULTS

IF significantly increased the mRNA expression of cardiac Atg-5 and pancreatic Atg-7 in Old-F-ISO versus old and adult groups. This was associated with a significant decrease in serum troponin-I, serum creatine kinase (CK-MB), cardiac malondialdehyde and cardiac TNF-α, fasting plasma glucose, and HOMA-IR in Old-F-ISO compared to Old-ISO group. Also, IF significantly decreased the age-related overall and visceral obesity in Old-F-ISO versus old and Old-ISO groups. Histological studies revealed attenuation of the local inflammatory response in Old-F-ISO versus Old-ISO group. Pancreatic Atg-7 and heart Atg-5 were significantly increased in Old-ISO versus old rats.

CONCLUSIONS

IF protects against acute AMI in old rats, possibly, via chronic activation of heart Atg-5 and pancreatic Atg-7, and alleviation of age-related overall and visceral obesity. Thus, IF could be a dietary lifestyle modification for attenuation of the susceptibility to acute AMI in aged population. On the other hand, acute activation of heart and pancreatic autophagy by ISO might augment cardiac injury.

Hyperglycemia in Medically Critically Ill Patients: Risk Factors and Clinical Outcomes

BACKGROUND

We aimed to robustly categorize glycemic control in our medical intensive care unit (ICU) as either acceptable or suboptimal based on time-weighted daily blood glucose averages of <180 mg/dL or >180 mg/dL; identify clinical risk factors for suboptimal control; and compare clinical outcomes between the 2 glycemic control categories.

METHODS

This was a retrospective cohort study in an academic tertiary and quaternary medical ICU.

RESULTS

Out of total of 974 unit stays over a 2-year period, 920 had complete data sets available for analysis. Of unit stays 63% (575) were classified as having acceptable glycemic control and the remaining 37% were classified (345) as having suboptimal glycemic control. Adjusting for covariables, the odds of suboptimal glycemic control were highest for patients with diabetes mellitus (odds ratio [OR] 5.08, 95% confidence interval [CI] 3.72-6.93), corticosteroid use during the ICU stay (OR 4.50, 95% CI 3.21-6.32), and catecholamine infusions (OR 1.42, 95% CI 1.04-1.93). Adjusting for acuity, acceptable glycemic control was associated with decreased odds of hospital mortality but not ICU mortality (OR 0.65, 95% CI 0.48-0.88 and OR 0.81, 95% CI 0.55-1.17, respectively). Suboptimal glycemic control was associated with increased odds of longer-than-predicted ICU and hospital stays (OR 1.76, 95% CI 1.30-2.38 and OR 1.50, 95% CI 1.12-2.01, respectively).

CONCLUSIONS

In our high-acuity medically critically ill patient population, achieving time-weighted average daily blood glucose levels <180 mg/dL reliably while in the ICU significantly decreased the odds of subsequent hospital mortality. Suboptimal glycemic control during the ICU stay, on the other hand, significantly increased the odds of longer-than-predicted ICU and hospital stay.

Prognostic values of fasting hyperglycaemia in non-diabetic patients with acute coronary syndrome: A prospective cohort study

Background:

Controversy remains regarding the prevalence of hyperglycaemia in non-diabetic patients hospitalised with acute coronary syndrome and its prognostic value for long-term outcomes.

Methods and results:

We evaluated the prevalence of hyperglycaemia (defined as fasting glycaemia ⩾10 mmol/l) among patients with no known diabetes at the time of enrolment in the prospective Special Program University Medicine-Acute Coronary Syndromes cohort, as well as its impact on all-cause death, myocardial infarction, stroke and incidence of diabetes at one year. Among 3858 acute coronary syndrome patients enrolled between December 2009–December 2014, 709 (18.4%) had known diabetes, while 112 (3.6%) of non-diabetic patients had hyperglycaemia at admission. Compared with non-hyperglycaemic patients, hyperglycaemic individuals were more likely to present with ST-elevation myocardial infarction and acute heart failure. At discharge, hyperglycaemic patients were more frequently treated with glucose-lowering agents (8.9% vs 0.66%, p&lt;0.001). At one-year, adjudicated all-cause death was significantly higher in non-diabetic patients presenting with hyperglycaemia compared with patients with no hyperglycaemia (5.4% vs 2.2%, p=0.041) and hyperglycaemia was a significant predictor of one-year mortality (adjusted hazard ratio 2.39, 95% confidence interval 1.03–5.56). Among patients with hyperglycaemia, 9.8% had developed diabetes at one-year, while the corresponding proportion among patients without hyperglycaemia was 1.8% (p&lt;0.001). In multivariate analysis, hyperglycaemia at presentation predicted the onset of treated diabetes at one-year (odds ratio 4.15, 95% confidence interval 1.59–10.86; p=0.004).

Conclusion:

Among non-diabetic patients hospitalised with acute coronary syndrome, a fasting hyperglycaemia of ⩾10 mmol/l predicted one-year mortality and was associated with a four-fold increased risk of developing diabetes at one year.

Meta-analysis of admission hyperglycaemia in acute myocardial infarction patients treated with primary angioplasty: a cause or a marker of mortality?

AIMS

Admission hyperglycaemia (AH) has been associated with worse outcomes in acute myocardial infarction (AMI). In the current review, we evaluated the impact of primary angioplasty (pPCI) on mortality in AMI patients with AH. Our second aim was to evaluate if AH is a marker of baseline risk or an independent predictor of mortality.

METHODS AND RESULTS

A comprehensive search of four major databases was performed. We included original research studies reporting data on mortality in AMI patients with AH (mean plasma glucose >156 mg/dL/8.7 mmol) and euglycaemia who were treated with pPCI. Of 481 citations, 12 studies were included in the analysis. Admission hyperglycaemia was associated with a higher 30-day [risk ratio (RR) 4.30, P < 0.0001] and 1- to 3-year mortality (RR 2.26, P < 0.0001). As well, AH was more prevalent in women and in patients with an increasing number of cardiac risk factors or angiographic predictors of mortality, such as previous AMI (RR 0.89, P = 0.01), multivessel coronary disease (RR 0.72, P = 0.0001), and involvement of left anterior descending artery (RR 0.92, P < 0.0001). Moreover, patients with AH had larger infarcts (higher creatine kinase-MB; P = 0.004) and more frequent ventricular arrhythmias (P = 0.002).

CONCLUSION

Despite rapid revascularization and treatment of hyperglycaemia, patients with AH continue to have a higher mortality. Admission hyperglycaemia occurs more commonly in patients who have traditional predictors of worse outcomes-specifically prior infarction, anterior wall infarctions, and multivessel disease. Likely, AH is a predictor of rather than a bona fide therapeutic target in AMI.

Effect of primary percutaneous coronary intervention on stress hyperglycaemia in myocardial infarction

AIM

To measure the effect of primary percutaneous coronary intervention on stress hyperglycaemia induced by ST segment elevation myocardial infarction.

METHODS

We measured blood glucose before primary percutaneous coronary intervention and 1 h after intervention in all patients presenting with ST segment elevation myocardial infarction for 2 months in our unit. A paired t-test was used for a statistical analysis.

RESULTS

From 157 patients accepted for primary percutaneous coronary intervention, 90 patients were included in the analysis. Blood glucose before intervention was 8.4 ± 2.46 mmol/l (mean ± SD) and after intervention was 7.9 ± 2.0 mmol/l (mean ± sd) (P = 0.003). In the subset of 15 patients with hyperglycaemia (glucose greater than 10 mmol/l), glucose before intervention was 12.7 ± 2.62 mmol/l (mean ± SD) and after intervention was 9.8 ± 3.42 mmol/l (mean ± sd) (P = 0.0002).

CONCLUSIONS

Blood glucose in patients with ST segment elevation myocardial infarction is significantly lower after primary percutaneous coronary intervention and this reduction is most marked in patients with hyperglycaemia. Waiting for the stress response to diminish means that 11.1% of patients' glucose levels fell below the treatment threshold of 10 mmol/l. Using the post-intervention blood glucose level avoids the need for treatment with insulin in this population. Further randomized studies are warranted to investigate the impact on mortality and morbidity of administering insulin triggered by pre-invention blood glucose vs. post-intervention blood glucose.

Stress hyperglycaemia in patients with first myocardial infarction

OBJECTIVE

To investigate the incidence of stress hyperglycaemia at first acute myocardial infarction (MI) with ST-segment elevation, occurrence of stress hyperglycaemia as a manifestation of previously undiagnosed abnormal glucose tolerance (AGT), and its relation to stress hormone levels.

MATERIALS AND METHODS

  The population of this prospective cohort study consisted of 243 patients. On admission glucose, adrenaline, noradrenaline and cortisol levels were measured. Patients without previously diagnosed diabetes (n = 204) underwent an oral glucose tolerance test on day 3 of hospitalisation and 3 months after discharge.

RESULTS

Abnormal glucose tolerance at day 3 was observed in 92 (45.1%) patients without a previous diagnosis of diabetes mellitus and resolved after 3 months in 46 (50.0%) patients (p < 0.0001). Stress hyperglycaemia, defined as admission glycaemia ≥ 11.1 mmol/l, affected 34 (14.0%) study participants: 28 (54.9%) patients with diabetes vs. 3 (8.8%) subjects with newly detected impaired glucose intolerance (p < 0.00001) and 1 (2.2%) person with AGT at day 3 (p < 0.000001). Multivariable analysis identified elevated glycated haemoglobin (HbA(1c) ; p < 0.0000001), anterior MI (p < 0.05) and high admission cortisol concentration (p < 0.001), but not catecholamines, as independent predictors of stress hyperglycaemia. The receiver operating characteristic curve analysis revealed the optimal cut-off values of 8.2% for HbA(1c) and 47.7 μg/dl for admission cortisol with very good and sufficient diagnostic accuracies respectively.

CONCLUSIONS

  Newly detected AGT in patients with a first MI is transient in 50% of cases. Stress hyperglycaemia is a common finding in patients with a first MI with ST-segment elevation and diabetes mellitus, but is rarely observed in individuals with impaired glucose tolerance or transient AGT diagnosed during the acute phase of MI. The risk factors of stress hyperglycaemia occurrence include elevated HbA(1c) , anterior MI and high admission cortisol concentration.

Glycemic control in critically ill patients

Hyperglycemia is common in critically ill patients and can be caused by various mechanisms, including nutrition, medications, and insufficient insulin. In the past, hyperglycemia was thought to be an adaptive response to stress, but hyperglycemia is no longer considered a benign condition in patients with critical illnesses. Indeed, hyperglycemia can increase morbidity and mortality in critically ill patients. Correction of hyperglycemia may improve clinical outcomes. To date, a definite answer with regard to glucose management in general intensive care unit patients, including treatment thresholds and glucose target is undetermined. Meta-analyses of randomized controlled trials suggested no survival benefit of tight glycemic control and a significantly increased incidence of hypoglycemia. Studies have shown a J- or U-shaped relationship between average glucose values and mortality; maintaining glucose levels between 100 and 150 mg/dL was likely to be associated with the lowest mortality rates. Recent studies have shown glycemic control < 180 mg/dL is not inferior to near-normal glycemia in critically ill patients and is clearly safer. Glycemic variability is also an important aspect of glucose management in the critically ill patients. Higher glycemic variability may increase the mortality rate, even in patients with the same mean glucose level. Decreasing glucose variability is an important issue for glycemic control in critically ill patients. Continuous measurements with automatic closed-loop systems could be considered to ensure that blood glucose levels are controlled within a specific range and with minimal variability.

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 restenosis after percutaneous coronary interventions in patients with diabetes mellitus: a report from the Insulin Diabetes Angioplasty study

OBJECTIVE

We investigated the impact of glucose control on target lesion restenosis after PCI in patients with type 2 diabetes.

METHODS

Ninety-three consecutive patients with type 2 diabetes accepted for PCI were randomised to intensified glucose control based on insulin (I-group; n=44) or to continue ongoing glucose-lowering treatment (C-group; n=49).The treatment target was a FBG of 5-7 mmol/L and HbA1c <6.5%. Information on target lesion restenosis after six months was available in 82 patients.

RESULTS

At baseline HbA1c and FBG did not differ between the I- and C-groups, respectively (HbA1c: 6.5 vs. 6.5%; p=1.0 and FBG: 7.0 vs. 7.3 mmol/L; p=0.3). After six months there was no significant change in HbA1c or FBG in either group (change in HbA1c: -0.2 vs.-0.1%; p=0.3 and in FBG: +0.2 vs. -0.3 mmol/L; p=0.3 in the I- and C-groups, respectively). Target lesion restenosis at six months did not differ, I vs. C = 41 and 44% (p=0.8). Independent predictors for restenosis were previous myocardial infarction (OR 8.0, 95% CI 2.5-25.7; p=<0.001) and FBG at baseline (OR for an increase by 1 mmol/L = 1.4, 95% CI 1.1-1.9; p=0.015).

CONCLUSIONS

Restenosis was predicted by baseline FBG suggesting that it would be of interest to target glucose normalisation in future trials. Intensified insulin treatment did not influence the rate of restenosis indicating that the main focus should be on lowering glucose rather than the tool to normalise glucose.

Association of stress hyperglycemia and atrial fibrillation in myocardial infarction

BACKGROUND

Stress hyperglycemia has an untoward effect on prognosis in acute myocardial infarction (AMI). Evidence on the interrelationship between stress hyperglycemia and atrial fibrillation (AF) in AMI is sparse. We hypothesized that stress hyperglycemia and AF, both being markers of worse in-hospital prognosis, may be interrelated and we therefore analyzed the relationship between stress hyperglycemia and AF in AMI.

PATIENTS AND METHODS

The study was a retrospective analysis of 543 patients with AMI. The average age was 63.8 +/- 10.6 years and 54.9% were male.

RESULTS

AF was more prevalent in 200 AMI patients with admission glucose >or= 8.0 mmol/l (15.00%) than in 343 patients with admission glucose < 8 mmol/l (7.87%), Pearson's chi-squared P = 0.010, OR 2.07 (95% CI 1.180-3.637). In AMI patients with neither stress hyperglycemia nor AF, in-hospital mortality was 1.67%; in patients with stress hyperglycemia without AF, the mortality was 3.85%. In patients with AF without stress hyperglycemia, mortality was high at 13.04%, and in patients with both stress hyperglycemia and AF it was extremely high at 24.14%. Hyperglycemia (r = 0.1680, P = 0.0472) but not AF correlated with the size of the AMI. Compared with an AF prevalence of 8.28% in the normoglycemic group, AF was found more often (14.65%) in a group with diabetes mellitus (DM), Pearson's chi-squared P = 0.02, OR = 2.04 (95% CI 1.06-3.93). There was no significant difference in the occurrence of AF between patients with previously diagnosed DM and those with new-onset DM (Fisher's exact test P = 0.34).

CONCLUSIONS

Stress hyperglycemia is associated with increased prevalence of AF in AMI. Patients with both stress hyperglycemia at admission (>or= 8.0 mmol/l) and AF had almost 14.5 times higher in-hospital mortality than patients who had neither stress hyperglycemia nor AF. Stress hyperglycemia was an independent predictor of the in-hospital mortality in multivariate regression analysis, but AF was not.

Oral glyburide, but not glimepiride, blocks the infarct-size limiting effects of pioglitazone

BACKGROUND

Many patients with type 2 diabetes mellitus receive several oral hypoglycemic agents, including sulfonylurea drugs. Intravenous glyburide (Glyb), a sulfonylurea agent, blocks the protective effects of "ischemic" and pharmacologic preconditioning in various animal models without affecting myocardial infarct size when administered alone. However, there are conflicting results when other sulfonylurea drugs are used. Pioglitazone (PIO) reduces infarct size in the rat. We asked whether oral Glyb and glimepiride (Glim) affect the infarct size-limiting effects of PIO.

METHODS

Sprague-Dawley rats received 3-day oral treatment with: PIO (5 mg/kg/day); PIO + Glyb (10 mg/kg/day); PIO + Glim (4 mg/kg/day) or water alone (experiment 1) or PIO (5 mg/kg/day) with or without 5-hydroxydecanoate (5HD, 10 mg/kg), a specific mitochondrial ATP-sensitive K+ channels inhibitor, administered intravenously 30 min before coronary artery ligation. PIO, Glyb and Glim were administered by oral gavage. Sugar 5% was added to water to prevent hypoglycemia. Rats underwent 30 min coronary artery occlusion and 4 h reperfusion (n = 6 in each group). Ischemic area at risk was assessed by blue dye and infarct size by triphenyl-tetrazolium-chloride.

RESULTS

Body weight and the size of the area at risk were comparable among groups. Infarct size (% of the area at risk) was significantly smaller in the PIO (14.3 +/- 1.1%; p < 0.001) and PIO + Glim (13.2 +/- 0.8%; p < 0.001) groups than in the control group (37.7 +/- 1.2%). Glyb completely blocked the effect of PIO (43.0 +/- 1.7%; p < 0.001). Glim did not affect the protective effect of PIO (p = 0.993). 5HD blocked the protective effect of PIO (infarct size 48.5 +/- 0.8% versus 14.8 +/- 0.6%, respectively; p < 0.0001). In conclusion, the infarct size limiting effects of PIO are dependent on activation of mitochondrial ATP-sensitive K+ channels. Oral Glyb, but not Glim, blocks the infarct size limiting effects of PIO. It is plausible that Glyb affects other pleiotropic effects of PIO and thus may attenuate favorable effects on cardiovascular outcomes. In contrast, Glim does not attenuate the protective effect of PIO.