Implications of hyperglycaemia and ethnicity in patients with acute coronary syndromes in New Zealand

Anemia, Hyperglycemia, and Reduced Left Ventricular Ejection Fraction Improve the GRACE Score's Predictability for In-hospital Mortality in Acute Coronary Syndrome; Single-Centre Cross-Sectional Study

Purpose

This study investigates the predictive value of incorporating anemia, hyperglycemia, and left ventricular ejection fraction (LVEF) into the Global Registry of Acute Coronary Events (GRACE) score for in-hospital mortality in Acute Coronary Syndrome (ACS).

Patients and Methods

We conducted a single-center, cross-sectional study involving 634 ACS patients admitted to Dr. Hasan Sadikin General Hospital between 2021 and 2023. Anemia was defined as hemoglobin <13 g/dL in men and <12 g/dL in women, while hyperglycemia was indicated with random blood glucose (RBG) ≥200 mg/dL at admission. Patients with LVEF <50% were classified as having reduced LVEF. The primary outcome was in-hospital mortality. Model goodness-of-fit was assessed using R2 and the Hosmer-Lemeshow's test. The predictive accuracy of the GRACE score alone and combined with these parameters were evaluated through receiver operating characteristic curve analysis, an area under the curve (AUC), and concordance (C)-statistics. Reclassification improvement was quantified using continuous net reclassification improvement (cNRI) and integrated discrimination improvement (IDI).

Results

Among 634 patients (mean age 58.10±11.08 years old; 80.3% male), anemia, hyperglycemia, and reduced LVEF were observed in 197 (31.1%), 123 (19.4%), and 364 (57.4%) patients, respectively. The in-hospital mortality rate was 6.6%. Regression analysis identified nine predictors of mortality, with anemia, hyperglycemia, and reduced LVEF confirmed as independent predictors. The GRACE score showed an AUC of 0.839 (95% confidence interval/CI 0.77-0.0.90). Incorporating anemia, hyperglycemia, and reduced LVEF increased the AUC to 0.862 (95% CI 0.81-0.91), enhancing predictive accuracy (p = 0.590). Combining these variables yielded an NRI of 0.075 (p = 0.070) and an IDI of 0.035 (p = 0.029).

Conclusion

Incorporating anemia, hyperglycemia, and reduced LVEF into the GRACE score improves its predictive capacity for in-hospital mortality in ACS patients. The modified GRACE score offers a more robust risk stratification tool for clinical practice and decision-making.

Admission hyperglycemia and all-cause mortality in diabetic and non-diabetic patients with acute myocardial infarction: a tertiary center analysis

Admission hyperglycemia (AH) is associated with worse prognosis in patients with acute myocardial infarction (AMI). Controversy remains whether the impact of AH differs among patients previously diagnosed with diabetes mellitus (DM). We retrospectively evaluated consecutive patients admitted in a coronary care unit with AMI, from 2006 to 2014. Patients were divided into 4 groups: patients without known DM with admission glycemia (AG) ≤ 143 mg/dL (group 1), patients without known DM with AG > 143 mg/dL (group 2), known DM with AG ≤ 213 mg/dL (group 3), and known DM with AG > 213 mg/dL (group 4). Primary outcome was defined as all-cause mortality during follow-up. A total of 2768 patients were included: 1425 in group 1, 426 in group 2, 593 in group 3, and 325 in group 4. After a median follow-up of 5.6 years, 1047 (37.8%) patients reached primary outcome. After multivariate analysis, group 4 was associated with the worst prognosis (HR 3.103, p < 0.001) followed by group 3 (HR 1.639, p = 0.002) and group 2 (HR 1.557, p = 0.039), when compared to group 1. When groups were stratified by type of AMI, patients in group 2 had a worse prognosis than patients in group 3 in the case of non-ST-segment elevation AMI. AH is associated with higher all-cause mortality in patients with AMI, irrespective of previous diabetic status.

Hyperglycemia in acute coronary syndromes: from mechanisms to prognostic implications

Hyperglycemia is a frequent condition in patients with acute coronary syndromes (ACS). Hyperglycemia during ACS is caused by an inflammatory and adrenergic response to ischemic stress, when catecholamines are released and glycogenolysis induced. Although the involved pathophysiological mechanisms have not yet been fully elucidated, it is believed that hyperglycemia is associated with an increase in free fat acids (which induce cardiac arrhythmias), insulin resistance, chemical inactivation of nitric oxide and the production of oxygen reactive species (with consequent microvascular and endothelial dysfunction), a prothrombotic state, and vascular inflammation. It is also related to myocardial metabolic disorders, leading to thrombosis, extension of the damaged area, reduced collateral circulation, and ischemic preconditioning. In the last few years, several observational studies demonstrated that hyperglycemia in ACS is a powerful predictor of survival, increasing the risk of immediate and long-term complications in patients both with and without previously known diabetes mellitus. Glucose management strategies in ACS may improve outcomes in patients with hyperglycemia, perhaps by reducing inflammatory and clotting mediators, by improving endothelial function and fibrinolysis and by reducing infarct size. Recent clinical trials of insulin in ACS have resulted in varying levels of benefit, but the clinical benefit of an aggressive treatment with insulin is yet unproved.