Relation of red cell distribution width to contrast-induced acute kidney injury in patients undergoing a primary percutaneous coronary intervention

Association of red blood cell distribution width and hemoglobin-to-RDW ratio with contrast-associated acute kidney injury in patients undergoing coronary angiography: A retrospective study

BACKGROUND

Inflammation contributes to poor prognosis in cardiovascular diseases. A novel biomarker for systemic inflammation that has garnered attention is the red blood cell distribution width (RDW). This study is designed to explore potential associations between RDW and hemoglobin-to-RDW ratio (HRR) with contrast-associated acute kidney injury (CA-AKI).

METHODS

This study retrospectively analyzed 4054 patients undergoing coronary angiography (CAG). Linear regression models were employed to assess the relationships between RDW or HRR and the elevation of serum creatinine (Scr). The associations between RDW or HRR and CA-AKI were explored using restricted cubic spline and log-binomial regression analyses taking into account specific cutoff values and quintiles. Exploratory analyses were also conducted to further investigate these associations.

RESULTS

Among enrolled patients, the average age was 66.9 years and 34.3% were female. Notably, patients who developed CA-AKI tended to have higher RDW and lower HRR. Multivariable linear regression models demonstrated that RDW exhibited a positive association with Scr elevation (β = 2.496, 95% confidence interval [CI] = 1.784-3.208), while HRR displayed a negative association (β = -3.559, 95% CI = -4.243 to -2.875). Multivariable log-binomial regression models confirmed that both high RDW (RDW ≥ 13.8%) and low HRR (HRR < 8.9) were significantly associated with a higher risk of CA-AKI (RDW [≥13.8% vs. <13.8%]: relative risk [RR] = 1.540, 95% CI = 1.345-1.762; HRR [<8.9 vs. ≥8.9]: RR = 1.822, 95% CI = 1.584-2.096). Exploratory analysis determined that such associations still existed regardless of age, gender, estimated glomerular filtration rate, or anemia.

CONCLUSIONS

Elevated preoperative RDW and decreased HRR were significantly associated with CA-AKI in patients undergoing CAG.

Prediction of the development of contrast‑induced nephropathy following percutaneous coronary artery intervention by machine learning

Contrast-induced nephropathy (CIN) is associated with increased mortality and morbidity in patients with coronary artery disease undergoing elective percutaneous coronary intervention(PCI). We developed a machine learning-based risk stratification model to predict contrast-induced nephropathy after PCI. A study retrospectively enrolling 240 patients eligible for PCI from December 2017 to May 2020 was performed. CIN was defined as a rise in serum creatinine levels ≥0.5 mg/dL or ≥25% from baseline within 72 h after surgery. Eight machine learning methods were performed based on clinical variables. Shapley Additive exPlanation values were also used to interpret the best-performing prediction models. Development of CIN was found in 37 patients(16.5%) after PCI. There were 11 significant predictors of CIN, including uric acid, peripheral vascular disease, cystatin C, creatine kinase-MB, haemoglobin, N-terminal pro-brain natriuretic peptide, age, diabetes, systemic immune-inflammatory index, total protein, and low-density lipoprotein. Regarding the efficacy of the machine learning model that accurately predicted CIN, SVM exhibited the most outstanding AUC value of 0.784. The SHAP and radar plots were used to illustrate the positive and negative effects of the 11 features attributed to the SVM. Machine learning models have the potential to identify the risk of CIN for elective PCI patients.

Association of preoperative neutrophil-lymphocyte ratio with acute kidney injury in patients with non-cardiac surgery: difference among surgical types

PURPOSE

To examine the relationship between Neutrophil-Lymphocyte Ratio (NLR) and Acute Kidney Injury (AKI) in patients undergoing noncardiac surgery, and subgroup analysis was performed for different types of non-cardiac surgery.

METHODS

The present retrospective cohort study included 10,159 adult patients who underwent major noncardiac surgery at Nanfang Hospital, Southern Medical University, between 2008 and 2018. Postoperative AKI was defined as an increase in serum creatinine level of at least 0.3 mg/dl within 48 h, or 1.5 times higher than baseline within 7 days postoperatively according to the Kidney Disease Improving Global Outcome. The correlation between preoperative NLR and postoperative AKI was determined by stepwise multivariate logistic regression analysis, and the predictive value of NLR was evaluated by the receiver operating characteristics curve (ROC) analysis.

RESULTS

Four hundred and eighty-five (4.77%) patients developed AKI postoperatively. Preoperative NLR was independently associated with postoperative AKI in all patients undergoing non-cardiac surgery (Odds ratio [OR], 1.03; 95% confidence interval [CI], 1.00-1.06). The optimal cut-off value of NLR was 2.12 according ROC analysis. The OR and 95% CI of AKI for NLR > 2.12 was 1.48 (1.21-1.81) compared with NLR ≤ 2.12. In addition, the positive association was mainly shown in patients undergone digestive system surgery with a cut-off value of 2.12 but not in neurological and musculoskeletal system surgeries.

CONCLUSION

The present study confirmed the association of preoperative NLR with postoperative AKI in digestive system surgical patients. A NLR value of 2.12 may be a useful cut-off to evaluate the risk of AKI.

A novel risk factor of contrast associated acute kidney injury in patients after enhanced computed tomography: a retrospective study

Background

Contrast associated acute kidney injury (CA-AKI) is a major cause of acute renal failure and the incidence of CA-AKI is still high in recent years. Risk stratification is traditionally based on glomerular filtration rate(GFR). Hence, the aim of this study was to explore the novel risk factors for CA-AKI after enhanced computed tomography (CT).

Methods

A retrospective cohort study was conducted in 632 in-hospital patients undergoing enhanced CT. The patients were divided into CA-AKI and no-CA-AKI groups. For comparative analyses, we applied one-to-four cohorts of those two groups using propensity score-matching methods addressing the imbalances of age, gender, weight, and smoking. The baseline clinical and biochemical data were compared. Logistic regression analysis was employed to investigate the CA-AKI risk factors. The receiver operating characteristic (ROC) curve was adopted to test the value of RDW in predicting CA-AKI after enhanced CT.

Results

25 (3.96%) patients suffered from CA-AKI. Those subjects who developed CA-AKI had advanced age, severer renal functional injury, lower albumin, higher baseline RDW, neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) than those without CA-AKI. It also exhibited more severe anemia including decreased hemoglobin and red blood cell count (all p < 0.05). The baseline RDW, albumin and PLR between the two groups were statistically significant different after PSM. Binary logistic regression analysis showed that baseline RDW, albumin and eGFR were correlated with CA-AKI after contrast-enhanced CT examination. The RDW exhibited moderated discrimination ability for predicting CA-AKI beyond eGFR, with an AUC of 0.803 (95% CI [0.702-0.90]) vs 0.765 (95% CI [0.70-0.83]).

Conclusion

Increased baseline RDW and decreased eGFR are risk factors for CA-AKI after enhanced CT. RDW exhibited good predictive value and can be used as an early warning marker for patients suffering from CA-AKI after enhanced CT.

Dynamic nomogram for predicting acute kidney injury in patients with acute ischemic stroke: A retrospective study

Background

This study sought to develop and validate a dynamic nomogram chart to assess the risk of acute kidney injury (AKI) in patients with acute ischemic stroke (AIS).

Methods

These data were drawn from the Medical Information Mart for Intensive Care III (MIMIC-III) database, which collects 47 clinical indicators of patients after admission to the hospital. The primary outcome indicator was the occurrence of AKI within 48 h of intensive care unit (ICU) admission. Independent risk factors for AKI were screened from the training set using univariate and multifactorial logistic regression analyses. Multiple logistic regression models were developed, and nomograms were plotted and validated in an internal validation set. Based on the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) to estimate the performance of this nomogram.

Results

Nomogram indicators include blood urea nitrogen (BUN), creatinine, red blood cell distribution width (RDW), heart rate (HR), Oxford Acute Severity of Illness Score (OASIS), the history of congestive heart failure (CHF), the use of vancomycin, contrast agent, and mannitol. The predictive model displayed well discrimination with the area under the ROC curve values of 0.8529 and 0.8598 for the training set and the validator, respectively. Calibration curves revealed favorable concordance between the actual and predicted incidence of AKI (p > 0.05). DCA indicates the excellent net clinical benefit of nomogram in predicting AKI.

Conclusion

In summary, we explored the incidence of AKI in patients with AIS during ICU stay and developed a predictive model to help clinical decision-making.

Red Cell Distribution Width at Admission Predicts the Frequency of Acute Kidney Injury and 28-Day Mortality in Patients With Acute Respiratory Distress Syndrome

OBJECTIVES

To determine the association of red cell distribution width (RDW) at admission with frequency of acute kidney injury (AKI) and 28-day mortality in acute respiratory distress syndrome (ARDS) patients.

METHODS

Two hundred fifty-eight ARDS patients were investigated in retrospective and prospective studies. The primary outcome was frequency of AKI. The secondary outcome was 28-day mortality.

RESULTS

The retrospective study included 193 ARDS patients, of which 67 (34.7%) were confirmed AKI and 76 (39.4%) died within 28 days. The RDW level in the AKI group was significantly higher than in the non-AKI group ([15.15 ± 2.59]% vs. [13.95 ± 1.89]%). Increased RDW was a significant predictor of frequency of AKI (odds ratio: 1.247, 95% confidence interval [CI]: 1.044, 1.489). The area under the receiver operating characteristic curve of RDW for predicting AKI was 0.687 (95%CI: 0.610, 0.764) and the cut-off value was 14.45 (sensitivity, 56.7%; specificity, 72.8%). In addition, the proportion of patients with RDW ≥ 14.45% in the non-survival group was notably higher compared with the survival group (48.7% vs. 29.1%). Furthermore, cox regression analysis revealed that RDW ≥ 14.45% was associated with 28-day mortality (hazard ratio: 1.817, 95%CI: 1.046, 3.158), while Kaplan-Meier analysis showed patients with RDW ≥ 14.45% had a significantly lower survival rate than those with RDW < 14.45%. The prospective study, on the other hand, included 65 ARDS patients, with frequency of AKI and 28-day mortality in the RDW ≥ 14.45% group significantly higher than in RDW < 14.45%.

CONCLUSION

RDW was a significant, independent predictor for frequency of AKI and 28-day mortality in ARDS patients.

Prognostic value of red cell distribution width in patients undergoing percutaneous coronary intervention: a meta-analysis

OBJECTIVE

To evaluate the prognostic value of baseline red cell distribution width (RDW) in patients with coronary artery diseases (CADs) undergoing percutaneous coronary intervention (PCI) by conducting a meta-analysis.

DESIGN

Systematic review and meta-analysis.

DATA SOURCE

PubMed, Embase, Wanfang, CNKI and VIP databases were searched from their inceptions to 19 June 2019.

ELIGIBLE CRITERIA

Studies investigating the value of baseline RDW for predicting all-cause mortality, cardiovascular mortality and major adverse cardiac events (MACEs) in patients with CAD undergoing PCI were included.

DATA EXTRACTION AND SYNTHESIS

Two authors independently extracted the data and evaluated the methodological quality using the Newcastle-Ottawa Scale. STATA V.12.0 software was applied to produce the forest plots using a random-effect model.

RESULTS

Twelve studies (13 articles) involving 17 113 patients were included and analysed. Comparison between the highest and lowest RDW category indicated that the pooled risk ratio (RR) was 1.77 (95% CI 1.32 to 2.37) for all-cause mortality, 1.70 (95% CI 1.25 to 2.32) for cardiovascular mortality and 1.62 (95% CI 1.21 to 2.18) for MACEs. The predictive effect of elevated RDW for all-cause mortality was stronger in the subgroup of patients without anaemia (RR 4.59; 95% CI 3.07 to 6.86) than with anaemia.

CONCLUSIONS

This meta-analysis indicated that elevated RDW was associated with higher risk of mortality and adverse cardiac events in patients with CAD undergoing PCI. The value of elevated RDW for predicting all-cause mortality appears to be stronger in patients without anaemia. RDW may be served as a promising prognostic biomarker in patients undergoing PCI.

The predictive value of RDW in AKI and mortality in patients with traumatic brain injury

Background

Red blood cell distribution width (RDW) has been validated valuable in predicting outcome and acute kidney injury (AKI) in several clinical settings. The aim of this study was to explore whether RDW is associated with outcome and AKI in patients with traumatic brain injury (TBI).

Methods

Patients admitted to our hospital for TBI from January 2015 to August 2018 were included in this study. Multivariate logistic regression analysis was performed to identify risk factors of AKI and outcome in patients with TBI. The value of RDW in predicting AKI and outcome was evaluated by receiver operating characteristic (ROC) curve.

Results

Three hundred and eighteen patients were included in this study. The median of RDW was 14.25%. We divided subjects into two groups based on the median and compared difference of variables between two groups. The incidence of AKI and mortality was higher in high RDW (RDW > 14.25) group (31.45% vs 9.43%, P < .001; 69.81% vs 29.56%, P < .001). Spearman's method showed RDW was moderately associated with 90‐day Glasgow Outcome Scale (GOS) (P < .001). In multivariate logistic regression analysis, RDW, lymphocyte, chlorine, and serum creatinine were risk factors of AKI. And Glasgow Coma Scale (GCS), glucose, chlorine, AKI, and RDW were risk factors of mortality. The area under the ROC curve (AUC) of RDW for predicting AKI and mortality was 0.724 (0.662‐0.786) and 0.754 (0.701‐0.807), respectively. Patients with higher RDW were likely to have shorter median survival time (58 vs 70, P < .001).

Conclusions

Red blood cell distribution width is an independent risk factor of AKI and mortality in patients with TBI.

Red blood cell distribution width predicts long-term mortality in critically ill patients with acute kidney injury: a retrospective database study

Acute kidney injury (AKI) is a serious complication in the intensive care unit (ICU), which may increase the mortality of critically ill patients. The red blood cell distribution width (RDW) has proved useful as a predictor of short-term prognosis in critically ill patients with AKI. However, it remains unknown whether RDW has a prognostic value of long-term all-cause mortality in these patients. The data of 18279 critically ill patients with AKI at first-time hospital admission were extracted from the Medical Information Mart for Intensive Care III (MIMIC-III) database. The tertiles of the RDW values were used to divide subjects into three groups, namely RDW < 13.6% for the low RDW group, 13.6% ≤ RDW < 15.2% for the middle RDW group and RDW ≥ 15.2% for the high RDW group. Demographic data, mortality, 4-year survival time and severity scale scores were compared among groups. The Kaplan-Meier analysis and the Cox regression analysis were performed to assess the impact of RDW on all-cause mortality in AKI patients. The receiver operating characteristic (ROC) curve analysis was done to evaluate the prognostic value of RDW on the long-term outcome of critically ill patients with AKI. The median age of the enrolled subjects was 65.6 years. AKI patients with a higher RDW value had significantly shorter survival time and higher death rate. By the Kaplan-Meier analysis, patients in the higher RDW group presented significantly shorter survival time and higher death rate. The Cox regression model indicated RDW as an independent risk factor of all-cause mortality of AKI patients (HR 1.219, 95% CI, 1.211 to 1.228). By the ROC analysis, RDW appeared more efficient in predicting long-term prognosis as compared with conventional severity scales. The AUC of RDW (95% CI, 0.712 to 0.725) was significantly higher than other severity scale scores. In conclusion, RDW is positively correlated to survival time of 4-year follow-up in critically ill patients with AKI, and RDW is an independent prognostic factor of long-term outcomes of these patients.

Could platelet-to-lymphocyte ratio be a predictor for contrast-induced nephropathy in patients with acute coronary syndrome?: A systematic review and meta-analysis

BACKGROUND

Contrast-induced nephropathy (CIN) is acute renal failure observed after administration of iodinated contrast media during angiographic or other medical procedures. In recent years, many studies have focused on biomarkers that recognize CIN and/or predict its development in advance. One of the many biomarkers studied is the platelet-to-lymphocyte ratio (PLR). We performed a systematic review and meta-analysis to evaluate the correlation between PLR level and CIN.

METHODS

Relevant studies were searched in PUBMED, EMBASE, and Web of Science until September 15, 2018. Case-control studies reporting admission PLR levels in CIN and non-CIN group in patients with acute coronary syndrome (ACS) were included. The pooled weighted mean difference (WMD) and 95% confidence intervals (95%CI) were calculated to assess the association between PLR level and CIN using a random-effect model.

RESULTS

Six relevant studies involving a total of 10452 ACS patients (9720 non-CIN controls and 732 CIN patients) met our inclusion criteria. A meta-analysis of 6 case-control studies showed that PLR levels were significantly higher in CIN group than those in non-CIN group (WMD = 33.343, 95%CI = 18.863 to 47.823, P < .001, I = 88.0%).

CONCLUSION

For patients with ACS after contrast administration, our meta-analysis shows that on-admission PLR levels in CIN group are significantly higher than those of non-CIN group. However, large and matched cohort studies are needed to validate these findings and assess whether there is a real connection or just an association.

Are Pre and Postoperative Platelet to Lymphocyte Ratio and Neutrophil to Lymphocyte Ratio Associated with Early Postoperative AKI Following CABG?

Objective

In this study, we investigated the role of two of the recent biomarkers of inflammation on the development of acute kidney injury in the early postoperative period of isolated coronary artery bypass grafting.

Methods

Three hundred and eleven patients, who underwent isolated coronary artery bypass grafting with cardiopulmonary bypass by the same surgery team in our clinic between May 2010 and October 2014, who had a preoperative serum creatinine level lower than 1.5 mg/dl were included in the study. These patients' records were reviewed retrospectively. The diagnosis of acute kidney injury was performed according to the Kidney Disease Improving Global Outcomes 2012 Acute Kidney Injury Guideline criteria. Patients who developed acute kidney injury in the early postoperative period were classified as Group-1 (n=62) and the patients with normal postoperative renal functions were classified as Group-2 (n=249). The demographic data, body mass index, comorbidities, hematologic/biochemical profiles, preoperative ejection fraction, blood transfusion history, and operative data of the groups were compared. Univariate analyses were performed to determine significant clinical factors, and multiple logistic regression analyses were subsequently done to determine independent predictors of acute kidney injury.

Results

Sixty-two (19.9%) patients developed acute kidney injury during the first 72 hours postoperatively. Multivariate logistic regression analyses revealed preoperative increased creatinine (P=0.0001), C-reactive protein (P=0.02), neutrophil-lymphocyte ratio (P=0.04) and platelet-lymphocyte ratio (P=0.002); increased postoperative first day leukocyte count (P=0.03), C-reactive protein levels (P=0.02), neutrophil-lymphocyte ratio (P=0.002), platelet-lymphocyte ratio (P=0.01) and increased intubation time (P=0.006) as independent predictors of early postoperative acute kidney injury in patients who underwent isolated coronary artery bypass grafting.

Conclusion

The preoperative and postoperative increased levels of neutrophil-lymphocyte ratio and platelet-lymphocyte ratio which can be calculated by simple methods from routine blood analysis showed us that these parameters are independent biomarkers directly related to development of acute kidney injury in the early postoperative period.

Contrast-induced acute kidney injury and adverse clinical outcomes risk in acute coronary syndrome patients undergoing percutaneous coronary intervention: a meta-analysis

Background

Recent studies have shown associations between contrast-induced acute kidney injury (CI-AKI) and increased risk of adverse clinical outcomes in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI); however, the estimates are inconsistent and vary widely. Therefore, this meta-analysis aimed to evaluate the precise associations between CI-AKI and adverse clinical consequences in patients undergoing PCI for ACS.

Methods

EMBASE, PubMed, Web of Science™ and Cochrane Library databases were systematically searched from inception to December 16, 2016 for cohort studies assessing the association between CI-AKI and any adverse clinical outcomes in ACS patients treated with PCI. The results were demonstrated as pooled risk ratios (RRs) with 95% confidence intervals (CI). Heterogeneity was explored by subgroup analyses.

Results

We identified 1857 articles in electronic search, of which 22 (n = 32,781) were included. Our meta-analysis revealed that in ACS patients undergoing PCI, CI-AKI significantly increased the risk of adverse clinical outcomes including all-cause mortality (18 studies; n = 28,367; RR = 3.16, 95% CI 2.52–3.97; I² = 56.9%), short-term all-cause mortality (9 studies; n = 13,895; RR = 5.55, 95% CI 3.53–8.73; I² = 60.1%), major adverse cardiac events (7 studies; n = 19,841; RR = 1.49, 95% CI: 1.34–1.65; I² = 0), major adverse cardiovascular and cerebrovascular events (3 studies; n = 2768; RR = 1.86, 95% CI: 1.42–2.43; I² = 0) and stent restenosis (3 studies; n = 130,678; RR = 1.50, 95% CI: 1.24–1.81; I² = 0), respectively. Subgroup analyses revealed that the studies with prospective cohort design, larger sample size and lower prevalence of CI-AKI might have higher short-term all-cause mortality risk.

Conclusions

CI-AKI may be a prognostic marker of adverse outcomes in ACS patients undergoing PCI. More attention should be paid to the diagnosis and management of CI-AKI.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1161-5) contains supplementary material, which is available to authorized users.

The Impact of Red Cell Distribution Width on the Development of Contrast-Induced Nephropathy in Patients with Stable Coronary Artery Disease who Underwent Coronary Angiography

Objectives:

Contrast-induced nephropathy (CIN) accounts for 10% of all causes of hospital-acquired renal failure. The pathophysiological cellular mechanism of the CIN development remains unclear and seems to be multifactorial. Herein, we aimed to determine the role of red cell distribution width (RDW) in the development of CIN after elective percutaneous intervention in patients with stable coronary artery disease, which in our opinion has not been researched enough.

Methods:

Between October 2009 and October 2011, a total of 211 patients with stable coronary artery disease who had undergone a coronary intervention procedure were evaluated prospectively. The patients were classified according to the development of CIN, and both groups were compared statistically according to clinical, laboratory, and demographic features, including the serum RDW level.

Results:

In 18.8% of the patients, CIN was observed. The mean age was 64±10.5, and 59% of the study group was male. An advanced age, male gender, hypertension, the serum total protein level, high density lipoprotein, and albumin levels were correlated with the development of CIN. The mean RDW level was 13.7±1.4%, and the mean creatinine level was 1.0±0.2 mg/dL. There was not any correlation between RDW and the presence of CIN (CIN[−]=13.8±1.5, CIN[+]=13.6±1.0, p>0.05), and also a multivariate regression analysis proved this non-correlation (OR : 0.92, 95% confidence interval [CI]=0.62–1.34; p: 0.67 ). There was only a correlation between hypertension and male gender with CIN that was proved with a multivariate regression analysis (OR=5.74, 95% CI: 1.96–16.79, p<0.01 vs OR=5.34, 95% CI=1.22–23.3, p: 0.02, respectively).

Conclusion:

Our outcomes indicate that the RDW has a limited use as a CIN predictor in patients with stable coronary artery disease.

Role of elevated red cell distribution width on acute kidney injury patients after cardiac surgery

Background

The aim of the study was to explore associations between elevated red cell distribution width (RDW) and acute kidney injury (AKI) in patients undergoing cardiac surgery (CS-AKI).

Methods

Preoperative, intraoperative and postoperative data of 10,274 patients undergoing cardiac surgery, including demographic data, were prospectively collected from January 2009 to December 2014. Propensity score matching was used on the basis of clinical characteristics and preoperative variables. An elevated RDW was defined as the difference between RDW 24 h after cardiac surgery and the latest RDW before cardiac surgery.

Results

A total of 10,274 patients were included in the unmatched cohort, and 3146 patients in the propensity-matched cohort. In the unmatched cohort, the overall CS-AKI incidence was 32.8% (n = 3365) with a hospital mortality of 5.5% (n = 185). In the propensity-matched cohort, the elevated RDW in AKI patients was higher than in patients without AKI (0.3% (0.0%, 0.7%) vs 0.5% (0.1, 1.1%), P <  0.001) and the elevated RDW incidences were 0.4% (0.1%, 0.9%), 0.6% (0.2%, 1.1%) and 1.1% (0.3%, 2.1%) in stage 1, 2 and 3 AKI patients (P <  0.001). Among propensity-matched patients with CS-AKI, the level of elevated RDW in non-survivors was higher than in survivors [1.2% (0.5%, 2.3%) vs 0.5% (0.1%, 1.0%), P <  0.001] and a 0.1% increase in elevated RDW was associated with a 0.24% higher risk of within-hospital mortality in patients with CS-AKI. Estimating the receiver-operating characteristic (ROC) area under the curve (AUC) showed that an elevated RDW had moderate discriminative power for AKI development (AUC = 0.605, 95% CI, 0.586–0.625; P <  0.001) and hospital mortality (AUC = 0.716, 95% CI, 0.640–0.764; P <  0.001) in the propensity-matched cohort.

Conclusions

An elevated RDW might be an independent prognostic factor for the severity and poor prognosis of CS-AKI.

The Value of Adding Red Cell Distribution Width to Mehran Risk Score to Predict Contrast-induced Acute Kidney Injury in Patients with Acute Coronary Syndrome

Background: Contrast-induced acute kidney injury (CI-AKI) is a relatively reversible cause of acute kidney injury (AKI) that occurs after radiocontrast media administration. It is a common complication after percutaneous coronary intervention, especially in patients with acute coronary syndrome (ACS). The aim of this study is to determine the utility of red cell distribution width (RDW) in predicting CI-AKI in patients with ACS and to determine the value of adding RDW to the Mehran risk score (MRS) on admission.

Methods: A total of 161 patients who presented with ST-elevation myocardial infarction (STEMI) or non-STEMI were identified retrospectively between January 2015 and December 2016. Patients were divided into two groups, those who developed CI-AKI after percutaneous coronary intervention (PCI) and those who did not.

Results: A total of 161 patients were analyzed. Of them, 12 developed CI-AKI (eight presented with STEMI and four presented with non-STEMI). RDW did not correlate with the development of CI-AKI (14.55 ± 1.48 vs 14.83 ± 1.21; p = 0.072). The areas under the receiver operating characteristic curves (ROCs) for RDW, MRS, and the combined model (MRS and RDW) for the prediction of CI-AKI were 0.721 (95% confidence interval (CI), 0.645 to 0.788; p=0.0024), 0.885 (95% CI, 0.825 to 0.930; p<0.0001), 0.890 (95% CI, 0.831 to 0.933; p<0.0001), respectively. Pairwise comparisons between ROCs for MRS vs the combined model yielded a non-significant p-value of 0.49. This signifies no added benefit for RDW to MRS for predicting CI-AKI.

Conclusion: RDW does not correlate with the development of CI-AKI in patients with ACS. The Mehran risk score remains a better indicator of CI-AKI risk assessment with no role for the addition of RDW to it. Further studies are needed to better assess predictors of CI-AKI in patients undergoing percutaneous coronary intervention.

Monocyte to High-Density Lipoprotein Ratio Predicts Contrast-Induced Nephropathy in Patients With Acute Coronary Syndrome

Contrast-induced nephropathy (CIN) is associated with worse prognosis in patients with acute coronary syndrome (ACS). Early identification and intervention for patients with a high risk of CIN are very important to improve clinical outcomes. Inflammation plays important role in the development of CIN in the setting of ACS. The monocyte to high-density lipoprotein ratio (MHR) is a novel inflammatory marker. Bleeding is also associated with worse prognosis in such patients. We aimed to investigate whether the preprocedural MHR had a predictive role for CIN development in such patients. In addition, using the thrombolysis in myocardial infarction classification, we aimed to assess whether there was any relationship between bleeding and CIN. A total of 647 patients (496 males; age: 63.3 ± 12.7 years) with ACS who underwent percutaneous coronary intervention (PCI) were included in the study. Seventy patients (10.8%) had developed CIN. Age, diabetes mellitus, contrast volume, estimated glomerular filtration rate, and MHR were independent predictors for CIN. Preprocedural MHR may be used as a simple marker of CIN. It may help with the early identification of patients with ACS who underwent PCI who are at high risk of CIN thus allowing the planning of protective measures.

Dynamic Change of Red Cell Distribution Width Levels in Prediction of Hospital Mortality in Chinese Elderly Patients with Septic Shock

Background:

The normal range of red cell distribution width (RDW) level is <15%. Several studies have indicated that a high RDW level was associated with mortality in critically ill patients, and the patients with a high RDW level need increased focus in clinical practice. In view of the difficulty in defining the specific value of high RDW level, the key is to focus on the patient with the level beyond the normal upper limit. This study aimed to determine whether dynamic change of RDW levels, rather than the level itself, is predictive of death in elderly patients with septic shock when RDW level is beyond 15%.

Methods:

Between September 2013 and September 2015, the elderly septic shock patients with RDW level beyond 15% were enrolled in this study. The RDW levels were measured at enrollment (day 1), and days 4 and 7 after enrollment. Sequential Organ Failure Assessment (SOFA) scores were recorded simultaneously.

Results:

A total of 45 patients, including 32 males and 13 females, were included in the final analysis. Based on their hospital outcomes, these patients were divided into the survivor group (n = 26) and the nonsurvivor group (n = 19). There were no significant differences in age, gender, body mass index, initial level of RDW, Acute Physiology and Chronic Health Evaluation II scores, and SOFA scores between survivors and nonsurvivors. At days 4 and 7 measurement, both RDW level (median [interquartile range]: day 4: 15.8 [2.0]% vs. 16.7 [2.0]%, P = 0.011; and day 7: 15.6 [1.8]% vs. 17.7 [2.5]%, P = 0.001) and SOFA scores (day 4: 7.0 [4.0] vs. 16.0 [5.0], P < 0.001, day 7: 5.5 [4.0] vs. 17.0 [5.0], P < 0.001) were significantly lower in survivors than those in nonsurvivors. Dynamic changes of RDW and SOFA scores in survivor group were significantly different from those in nonsurvivor group (all P < 0.05). Continuous increase in RDW level was observed in 10 of the 13 nonsurvivors, but only in 3 of the 26 survivors. The level of RDW7 and dynamic changes significantly correlated with their counterparts of SOFA scores (all P < 0.05), whereas the levels of RDW1 and RDW4 had no significant correlation with their counterparts of SOFA scores (all P > 0.05).

Conclusions:

Continuous increase in RDW level, rather than the level of RDW itself, was more useful in predicting hospital death in elderly patients with septic shock when the level of RDW was >15%. The dynamic changes of RDW were highly correlated with the SOFA score in the patients.

Red Blood Cell Distribution Width is an Independent Predictor of AKI and Mortality in Patients in the Coronary Care Unit

BACKGROUND/AIMS

We investigated the hypothesis that RDW is an independent predictor of acute kidney injury (AKI) and mortality in patients in the coronary care unit (CCU).

METHODS

In this prospective, observational study, we screened 412 adults admitted to the CCU at Zhongnan Hospital of Wuhan University from January 1, 2014 to June 1, 2015. AKI was defined based on the KDIGO-AKI criteria. The survivors were followed up for up to 2 years after hospital discharge. The primary endpoint of the study was the incidence of AKI, while the secondary endpoints of the study were in-hospital mortality and 2-year mortality.

RESULTS

RDW was significantly correlated with the acute physiology and chronic health evaluation II (APACHEII) score, hemoglobin, mean corpuscular volume, inflammatory marker levels, nutrition and renal function at the time of CCU admission. The incidence of AKI was much higher in the high RDW group (RDW ≥14.0%) than in the low RDW group, a finding that was confirmed by multivariable logistic regression, which showed that RDW was independently associated with the incidence of AKI (odds ratio (OR), 1.059, 95% coincidence interval (95% CI), 1.024-1.095, P=0.001). A total of 61 patients died during their hospital stay, and baseline RDW was also an independent predictor of in-hospital mortality (hazard ratio (HR), 1.129, 95% CI 1.005-1.268, P=0.041). Patients with a high RDW exhibited significantly higher 2-year mortality than patients with a low RDW during a median follow-up period of 19.8 months (P<0.001), and RDW independently predicted the risk of 2-year mortality (HR, 1.189, 95% CI 1.045 to 1.354, P=0.009) in the multivariate Cox proportional hazard analysis after adjustments for other clinical and laboratory variables.

CONCLUSION

RDW is an independent predictor of AKI and mortality in patients in the CCU.

Red cell distribution width predicts incident dipstick albuminuria in Korean adults without chronic kidney disease

BACKGROUND

Red cell distribution width (RDW) is an emerging marker of inflammation and a predictor of high cardiovascular morbidity and mortality as well as all-cause mortality. A previous cross-sectional study showed that RDW was associated with microalbuminuria, an indicator of target organ damage. However, the longitudinal association of RDW and development of albuminuria is not known.

METHODS

We analyzed 83,040 participants without chronic kidney disease (CKD) at baseline who underwent two health check-ups at a 4-year interval during 2005 to 2014. Urine albumin was determined by single urine dipstick semi-quantitative analysis, and incident albuminuria was defined as ≥ 1+ dipstick albumin at the second check-up. We used logistic regression analysis to determine the relationship between RDW and incident albuminuria.

RESULTS

Participants were divided into quartiles according to baseline RDW. After 4 years, 982 cases of incident albuminuria were observed. The cumulative incidences of albuminuria were 0.94, 1.05, 1.18, and 1.62% for the 1st through 4th quartiles of RDW, respectively. Multivariate logistic analysis showed that the odds ratios (95% confidence interval) for incident albuminuria compared to those in the 1st quartile were 1.11 (0.92-1.34), 1.26 (1.04-1.52), and 1.88 (1.58-2.24) for the 2nd, 3rd and 4th quartiles, respectively.

CONCLUSION

RDW was associated with development of albuminuria in relatively healthy Korean adults without CKD. Further research is needed to verify the role of RDW in the development of albuminuria and renal injury.

Preprocedural Prediction Model for Contrast-Induced Nephropathy Patients

Background

Several models have been developed for prediction of contrast‐induced nephropathy (CIN); however, they only contain patients receiving intra‐arterial contrast media for coronary angiographic procedures, which represent a small proportion of all contrast procedures. In addition, most of them evaluate radiological interventional procedure‐related variables. So it is necessary for us to develop a model for prediction of CIN before radiological procedures among patients administered contrast media.

Methods and Results

A total of 8800 patients undergoing contrast administration were randomly assigned in a 4:1 ratio to development and validation data sets. CIN was defined as an increase of 25% and/or 0.5 mg/dL in serum creatinine within 72 hours above the baseline value. Preprocedural clinical variables were used to develop the prediction model from the training data set by the machine learning method of random forest, and 5‐fold cross‐validation was used to evaluate the prediction accuracies of the model. Finally we tested this model in the validation data set. The incidence of CIN was 13.38%. We built a prediction model with 13 preprocedural variables selected from 83 variables. The model obtained an area under the receiver‐operating characteristic (ROC) curve (AUC) of 0.907 and gave prediction accuracy of 80.8%, sensitivity of 82.7%, specificity of 78.8%, and Matthews correlation coefficient of 61.5%. For the first time, 3 new factors are included in the model: the decreased sodium concentration, the INR value, and the preprocedural glucose level.

Conclusions

The newly established model shows excellent predictive ability of CIN development and thereby provides preventative measures for CIN.

The Predictive Role of Red Cell Distribution Width in Mortality among Chronic Kidney Disease Patients

Background

Recently, accumulating evidence has demonstrated that RDW independently predicts clinically important outcomes in many populations. However, the role of RDW has not been elucidated in chronic kidney disease (CKD) patients. We conducted the present study with the aim to evaluate the predictive value of RDW in CKD patients.

Methods

A retrospective observational cohort study of 1075 stage 3–5 CKD patients was conducted in a medical center. The patients’ baseline information included demographic data, laboratory values, medications, and comorbid conditions. The upper limit of normal RDW value (14.9%) was used to divide the whole population. Multivariate Cox regression analysis was used to determine the independent predictors of mortality.

Results

Of the 1075 participants, 158 patients (14.7%) died over a mean follow-up of approximately 2.35 years. The crude mortality rate was significantly higher in the high RDW group (high RDW group, 22.4%; low RDW group 11%, p <0.001). From the adjusted model, the high RDW group was correlated with a hazard ratio of 2.19 for overall mortality as compared with the low RDW group (95% CI = 1.53–3.09, p<0.001). In addition, the high RDW group was also associated with an increased risk for cardiovascular disease (HR = 2.28, 95% CI = 1.14–4.25, p = 0.019) and infection (HR = 1.9, 95% CI = 1.15–3.14, p = 0.012)) related mortality in comparison with the low RDW group.

Conclusions

In stage 3–5 CKD patients, RDW was associated with patient mortality of all-cause, cardiovascular disease and infection. RDW should be considered as a clinical predictor for mortality when providing healthcare to CKD patients.

Association of Neutrophil-to-lymphocyte Ratio with Contrast-induced Nephropathy in Patients with Non-ST-elevation Acute Coronary Syndrome Treated with Percutaneous Coronary Intervention

BACKGROUND

A higher neutrophil-to-lymphocyte ratio (NLR) is associated with poor clinical outcomes in various cardiovascular diseases, including acute coronary syndromes. However, the relationship between NLR and contrast-induced nephropathy (CIN) in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI) has not been known. Hence, we investigated whether admission NLR is associated with CIN after PCI in patients with NSTE-ACS.

METHODS

A total of 478 patients (mean age 62.8±12.6 years, and 64.2% men), who were admitted to our hospital for NSTEACS and underwent PCI with stent, were recruited. Neutrophil-to-lymphocyte ratio was calculated via dividing neutrophil count by lymphocyte count. The patients were divided into two groups: CIN (+) and CIN (-). Contrast-induced nephropathy was defined as a ≥0.5mg/dL and/or a ≥25% increase in serum creatinine within 48-72hours post-PCI.

RESULTS

Admission NLR was significantly higher in patients with CIN than in patients without CIN (median 5.43, interquartile range 3.23-7.73 vs. median 2.59, interquartile range 1.83-3.88, P<0.001). On multivariate analysis, NLR ≥ 3.46 value (OR=2.631, 95%CI 1.146-6.060, P=0.022), estimated glomerular filtration rate (OR=0.963, P=0.004), high sensitivity C-reactive protein (OR=1.028, P=0.016) were independent factors of CIN.

CONCLUSION

Increased NLR is independently associated with risk of CIN in NSTE-ACS patients treated by PCI.

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.