Red blood cell indices and development of hospital-acquired anemia during acute myocardial infarction

Red Blood Cell Distribution Width is a Biomarker of Red Cell Dysfunction Associated with High Systemic Inflammation and a Prognostic Marker in Heart Failure and Cardiovascular Disease: A Potential Predictor of Atrial Fibrillation Recurrence

At the beginning of the 21st century, approximately 2.3 million US adults had atrial fibrillation (AF), and there has been a 60% increase in hospital admissions for AF. Given that the expectancy is a continuous increase in incidence, it portends a severe healthcare problem. Considerable evidence supports the immune system and inflammatory response in cardiac tissue, and circulatory processes are involved in the physiopathology of AF. In this regard, finding novel inflammatory biomarkers that predict AF recurrence after catheter ablation (CA) is a prime importance global healthcare problem. Many inflammatory biomarkers and natriuretic peptides came out and were shown to have predictive capabilities for AF recurrence in patients undergoing CA. In this regard, some studies have shown that red blood cell distribution width (RDW) is associated with the risk of incident AF. This review aimed to provide an update on the evidence of the RDW as a biomarker of red cell dysfunction and its association with high systemic inflammation, and with the risk of incident AF. Through the literature review, we will highlight the most relevant studies of the RDW related to AF recurrence after CA. Many studies demonstrated that RDW is associated with all cause-mortality, heart failure, cardiovascular disease, and AF, probably because RDW is a biomarker of red blood cell dysfunction associated with high systemic inflammation, reflecting an advanced heart disease with prognostic implications in heart failure and cardiovascular disease. Thus, suggesting that could be a potential predictor for AF recurrence after CA. Moreover, the RDW is a parameter included in routine full blood count, which is low-cost, quick, and easy to obtain. We provided an update on the evidence of the most relevant studies of the RDW related to AF recurrence after CA, as well as the mechanism of the high RDW and its association with high systemic inflammation and prognostic marker in cardiovascular disease and heart failure.

Predictors of Revascularization in Patients with Unstable Angina

BACKGROUND

The factors that determine the necessity of coronary artery revascularization in patients with unstable angina (UA) have been supported by limited data. Therefore, this study aimed to identify the predictors of revascularization in patients with UA.

METHODS

The study included the recorded data of 3668 patients with UA who underwent cardiac catheterization (age 66 ± 9.2, men 70%); 2615 of them (71%) underwent revascularization (percutaneous transluminal coronary angioplasty (PTCA), coronary artery bypass graft (CABG), or hybrid revascularization. The remaining 1053 patients (29%) had no significant coronary stenosis and were regarded as controls. Multivariable logistic regression analysis was performed to separate the predictors of revascularization.

RESULTS

It was found that severe angina (OR 2.7, 95%CI 1.9-3.7), male gender (OR 1.4, 95%CI 1.1-1.7), and hyperlipidemia were the predictors of revascularization. It was also noted that intraventricular conduction disorders including left and right bundle branch blocks and a history of previous revascularization and myocardial infarction were associated with lower odds of revascularization.

CONCLUSION

Overall, however, the predictive value of the studied factors proved to be poor and may still point to the multifactorial nature of significant coronary artery stenosis and the need for revascularization in patients with UA.

Risk Factors Analysis for Hemoglobin Decline Caused by Diagnostic Blood Collection in Respiratory Department in North China: A Case-Control Study

Purpose

This study aimed to investigate the correlation between hemoglobin decline and diagnostic blood collection in the respiratory department and analyze the decline's risk factors.

Patients and Methods

A case-control study in the respiratory department of a national tertiary hospital in north China, multivariable logistic regression analysis was used to find the risk factors. Patients excluding other factors affecting hemoglobin other than blood collection in the year 2021 were enrolled and divided into two groups according to the D-value of hemoglobin. The degree of hemoglobin decline caused by diagnostic blood collection between discharge and admission and its risk factors were analyzed.

Results

Among the 530 patients screened in the study, ΔHb (the D-value of hemoglobin between discharge and admission) showed a skewed distribution with an average value of -4.38±0.514 g/L. We defined the D-value less than mean-2SD (ΔHb<-5.408) as a significant hemoglobin decline, by which the patients were categorized into two groups. Some variables had apparent differences between the two groups. By multivariable logistic regression analysis on these variables, the independent risk factors for significant hemoglobin decline (ΔHb<-5.408g/L) were revealed: age (OR=1.020, 95% CI 1.008-1.032, p=0.001), Male gender (OR=1.544, 95% CI 1.011-2.358, p=0.044), hemoglobin value at admission (OR=1.052, 95% CI 1.039-1.065, p<0.001), total blood collection volume (OR=1.021, 95% CI 1.010-1.032, p<0.001).

Conclusion

In the respiratory department, older male and more diagnostic blood collection mean higher risks of significant hemoglobin decline. Surprisingly, the lower the hemoglobin value at admission, the lower the risk.

Relationship Between Red Cell Distribution Width and Oxidative Stress Indexes in Patients with Coronary Artery Disease

Background

Red blood cell distribution (RDW), an index of the size variability of erythrocytes, is significantly associated with coronary stenosis and can strongly predict the mortality risk in coronary artery disease (CAD). The biological mechanisms involved are not fully understood but may include oxidative stress. We sought to investigate the relationship between RDW and markers of oxidative stress in patients with CAD.

Methods

Participants were 112 consecutive patients referred to department of cardiac surgery for evaluation of chest pain. 32 patients had stable CAD, 40 patients had unstable CAD and 40 subjects were diagnosed as non-CAD. The levels of lipid peroxidation (TBARS) were measured in plasma and membrane samples by a fluorometric method. The plasma levels of glutathione (GSH) and total antioxidant capacity (TAC) were determined using spectrophotometric methods.

Results

Lipid peroxidation levels were significantly higher in the erythrocyte membrane of stable CAD patients than non-CAD patients. The levels of TAC were significantly lower in both stable and unstable groups when compared to that of the control group (P< 0.019 and P< 0.001, respectively), but did not differ between stable and unstable CAD. In addition, there was no significant difference in the serum GSH levels among the study groups. Membrane TBARS was directly associated with RDW in three groups of study.

Conclusions

We found an independent association between RDW levels and membrane lipid peroxidation in patients with CAD. This finding suggests that oxidative stress may be a potential underlying biological mechanism for increased RDW in CAD patients.

Red Blood Cell Distribution Width as Novel Biomarker in Cardiovascular Diseases: A Literature Review

Red blood cell distribution width (RDW) is a measure of the change in size of red blood cells and it is used in combination with other hematological parameters for the differential diagnosis of anemias. Recent evidence suggested that the change in RDW level may be a predictive biomarker of morbidity and mortality in cardiovascular diseases (CVDs). Cardiovascular diseases are the most common cause of death globally as compared to cancer and communicable diseases. Early diagnosis and prompt intervention of these diseases are very important to minimize their complications. Nowadays, the diagnosis of most cardiovascular diseases majorly depends on clinical judgment, electrocardiography and biochemical parameters. Red blood cell distribution width as a new predictive biomarker may play a pivotal role in assessing the severity and progression of CVDs. However, the underlying mechanisms for the association between RDW and CVDs are not clear. A deeper understanding of their association could help the physicians in more careful identification, early prevention, intervention, and treatment to prevent adverse cardiovascular events. This review aims to elaborate on the recent knowledge on the association between RDW and cardiovascular diseases and some possible pathophysiological mechanisms.

Association Between Hemoglobin and Major Adverse Cardiac Events: A Secondary Analysis from a Retrospective Cohort Study

BACKGROUND

This study aims to investigate the association between hemoglobin and major adverse cardiac events (MACE) in patients with stable coronary artery disease (CAD) who were treated with percutaneous coronary intervention (PCI).

METHODS

This was a secondary analysis based on a retrospective cohort study involving 204 patients with stable CAD. Patients were divided into four groups according to hemoglobin levels (Q1: 6.90-12.30 g/dL; Q2: 12.40-13.80 g/dL; Q3: 13.90-14.90 g/dL; Q4: 15.00-19.00 g/dL). Lasso regression analysis was performed to select characteristic variables and reduce dimensions. Odds ratio (OR) and 95% confidence interval (CI) were used for comparing data among groups.

RESULTS

After an average follow-up of 783 days, 28/204 (17.72%) patients with CAD occurred MACE. Univariate analysis data showed that hemoglobin level was negatively associated with the incidence of MACE in patients with CAD treated with PCI (Q2 vs Q1: OR=0.19, P=0.005; Q3 vs Q1: OR=0.25, P=0.013; Q4 vs Q1: OR=0.13, P=0.002). The negative correlation between hemoglobin and MACE still existed after adjusting selected variables obtained from multivariate regression analysis (Q2 vs Q1: OR= 0.18, P=0.007; Q3 vs Q1: OR=0.29, P=0.038; Q4 vs Q1: OR=0.19, P=0.016). Curve fitting illustrated that hemoglobin level presented a non-linear and negative association with MACE in patients with CAD treated with PCI.

CONCLUSIONS

Hemoglobin level can be utilized as a prognostic indicator of MACE in patients with CAD after PCI.

Tackling the unknowns in understanding and management of hospital acquired anemia

Hospital acquired anemia (HAA) has been a recognized entity for nearly 50 years. Despite multiple hypotheses, a mechanistic understanding is lacking, and targeted interventions have not yet yielded significantly impactful results. Known risk factors include advanced age, multiple co-morbidities, low bone marrow reserve, admission to the intensive care unit, and frequent phlebotomy. However, confounding variables in many studies continues to complicate the identification of additional risk factors. Improved understanding of iron metabolism, erythropoiesis, and the erythroid iron restriction response in the last few decades, as well as the recent demonstration of poor outcomes correlating with increased transfusion have refocused attention on HAA. While retrospective database studies provide ample correlative data between 1) HAA and poor outcomes; 2) reduction of phlebotomy volume and decrease in transfusion requirement; and 3) over-transfusion and increased mortality, no causal link between reduced phlebotomy volume, decreased rates of HAA, and improved mortality or other relevant outcomes have been definitely established. Here, we review the current state of knowledge and provide a summary of potential directions to understand and mitigate HAA. There are at present no clear guidelines on whether and when to evaluate hospitalized patients for underlying causes of anemia. We thus provide a guide for clinicians in general practice toward identifying patients at the highest risk for HAA, decreasing blood loss through phlebotomy to the greatest degree feasible, and evaluating and treating reversible causes of anemia in a targeted population.

Classification of hospital acquired complications using temporal clinical information from a large electronic health record

Hospital acquired complications (HACs) are serious problems affecting modern day healthcare institutions. It is estimated that HACs result in an approximately 10% increase in total inpatient hospital costs across US hospitals. With US hospital spending totaling nearly $900 billion per annum, the damages caused by HACs are no small matter. Early detection and prevention of HACs could greatly reduce strains on the US healthcare system and improve patient morbidity & mortality rates. Here, we describe a machine-learning model for predicting the occurrence of HACs within five distinct categories using temporal clinical data. Using our approach, we find that at least $10 billion of excessive hospital costs could be saved in the US alone, with the institution of effective preventive measures. In addition, we also identify several keystone features that demonstrate high predictive power for HACs over different time periods following patient admission. The classifiers and features analyzed in this study show high promise of being able to be used for accurate prediction of HACs in clinical settings, and furthermore provide novel insights into the contribution of various clinical factors to the risk of developing HACs as a function of healthcare system exposure.

The Prognostic Role of Red Blood Cell Distribution Width in Coronary Artery Disease: A Review of the Pathophysiology

Red blood cell distribution width (RDW) is a measure of red blood cell volume variations (anisocytosis) and is reported as part of a standard complete blood count. In recent years, numerous studies have noted the importance of RDW as a predictor of poor clinical outcomes in the settings of various diseases, including coronary artery disease (CAD). In this paper, we discuss the prognostic value of RDW in CAD and describe the pathophysiological connection between RDW and acute coronary syndrome. In our opinion, the negative prognostic effects of elevated RDW levels may be attributed to the adverse effects of independent risk factors such as inflammation, oxidative stress, and vitamin D₃ and iron deficiency on bone marrow function (erythropoiesis). Elevated RDW values may reflect the intensity of these phenomena and their unfavorable impacts on bone marrow erythropoiesis. Furthermore, decreased red blood cell deformability among patients with higher RDW values impairs blood flow through the microcirculation, resulting in the diminution of oxygen supply at the tissue level, particularly among patients suffering from myocardial infarction treated with urgent revascularization.

Variation in the incidence of hospital-acquired anemia during hospitalization with acute myocardial infarction (data from 57 US hospitals)

Development of hospital-acquired anemia (HAA) during acute myocardial infarction may be related to processes of care and is associated with poor outcomes. Little is known about variation in the incidence of HAA across hospitals or the hospital characteristics associated with HAA. We studied 17,676 patients with acute myocardial infarction without anemia at admission, defining HAA as a hemoglobin decline below anemia diagnostic thresholds and moderate-to-severe HAA as a hemoglobin decline to <11 g/dl. We calculated median rate ratios (MRRs), the median value of the relative risk (RR) for HAA for 2 patients with identical characteristics presenting to 2 randomly selected hospitals, to identify variation in HAA adjusting for patient characteristics. Separate models were fit to test the association between hospital characteristics and HAA. HAA (57.5%) and moderate-to-severe HAA (20.1%) were common. The incidence of HAA varied substantially across hospitals and remained significant after multivariable adjustment (any HAA: MRR 1.09, 95% confidence interval (CI) 1.07 to 1.13; moderate-to-severe HAA: MRR 1.27, 95% CI 1.19 to 1.39). Adjusting for patient characteristics, teaching status (RR 0.91, 95% CI 0.84 to 0.97 vs nonteaching status), and region (Northeast vs Midwest: RR 1.10, 95% CI 1.01 to 1.19; West vs Midwest: RR 1.19, 95% CI 1.06 to 1.33, respectively) was associated with risk of HAA. Teaching status (RR 0.7, 95% CI 0.6 to 0.9 vs nonteaching status) and region (South vs Midwest: RR 1.3, 95% CI 1.0 to 1.5) were independently associated with moderate-to-severe HAA. In conclusion, we observed significant variability in the incidence of HAA across hospitals and found a lower risk of HAA at teaching centers, suggesting that qualitative studies of the relation between HAA and processes of care are needed to identify targets for quality improvement.

Red blood cell distribution width is longitudinally associated with mortality and anemia in heart failure patients

BACKGROUND

Red blood cell distribution width (RDW) has been found to be an independent predictor for adverse outcome in patients with heart failure (HF), but there are no data on the association of longitudinal RDW with all-cause mortality and occurrence of anemia.

METHODS AND RESULTS

1,702 patients discharged from a previous admission for acute HF (AHF) were included. RDW was measured during the available longitudinal history of the patient. Joint modeling and Multistate Markov were used for the analysis. The median RDW at baseline was 15.0% (IQR: 14.0-16.5), and 45.6% of patients had anemia. At a median follow-up of 1.5 years (IQR: 0.45-3.25), 713 patients died. The last RDW-trajectory value and cumulative RDW-trajectory mean were predictive of mortality (HR, 1.18; 95% CI: 1.12-1.24; and HR, 1.12; 95% CI: 1.08-1.16, respectively; P<0.001 for both). This effect, however, varied according the anemia status (P for interaction<0.001), being more pronounced in absence of anemia [HR=1.31 (95% CI: 1.22-1.42) and HR=1.48 (95% CI: 1.33-1.64)] compared to those with anemia [HR=1.08 (95% CI: 1.04-1.13), 1.12 (95% CI: 1.06-1.18)]. Longitudinal RDW (per 1% increasing) was also independently associated with incident anemia [HR=1.10 (95% CI: 1.03-1.18) P=0.002].

CONCLUSIONS

Following an admission for AHF, higher longitudinal RDW values over time were associated to an increased risk for both developing anemia and dying. The effect on mortality was more pronounced among non-anemic patients.