Exploring the Correlates of Hematological Parameters With Early Diabetic Nephropathy in Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes mellitus (DM) with nephropathy is a common complication in poorly controlled diabetes. Uncontrolled DM leads to intraglomerular vascular changes that cause physical injury to capillary walls, causing a profibrotic response in kidneys. The present study aimed to determine the association of hematological markers with microalbuminuria in early diabetic nephropathy.

METHODS

A single-center, cross-sectional study was conducted over the period of two years at the Department of Medicine of Pradyumna Bal Memorial Hospital, Kalinga Institute of Medical Sciences. A total of 90 patients diagnosed with type 2 DM were classified into two groups (group A and group B) according to microalbuminuria; there were 45 patients in each group. Levels of hematological markers, i.e., neutrophil-to-lymphocyte ratio (NLR) and red cell distribution width (RDW), between the study groups were examined and compared.

RESULTS

A significant difference in NLR was found between groups A and B (p = 0.001). A statistically significant difference in RDW was found between the groups (p = 0.015). Receiver operating characteristic curve analysis of inflammatory markers and microalbuminuria prediction showed an area under the curve of 0.814 for NLR and 0.656 for RDW.

CONCLUSION

Hematological parameters like NLR and RDW are elevated in early diabetic nephropathy patients. NLR is found to be a better marker than RDW in predicting early nephropathy.

The Role of Red Cell Distribution Width as a Prognostic Marker in Chronic Liver Disease: A Literature Review

Liver disease is one of the leading public health problems faced by healthcare practitioners regularly. As such, there has been a search for an inexpensive, readily available, non-invasive marker to aid in monitoring and prognosticating hepatic disorders. Recently, red blood cell distribution width (RDW) has been found to be associated with various inflammatory conditions with implications for its use as a potential marker for assessing disease progression and prognosis in multiple conditions. Multiple factors effect red blood cell production whereby a dysfunction in any process can lead to anisocytosis. Furthermore, a chronic inflammatory state leads to increased oxidative stress and produces inflammatory cytokines causing dysregulation and increased intracellular uptake and use of both iron and vitamin B12, which leads to a reduction in erythropoiesis causing an increase in RDW. This literature review reviews in-depth pathophysiology that may lead to an increase in RDW and its potential correlation with chronic liver diseases, including hepatitis B, hepatitis C, hepatitis E, non-alcoholic fatty liver disease, autoimmune hepatitis, primary biliary cirrhosis, and hepatocellular carcinoma. In our review, we examine the use of RDW as a prognostic and predictive marker for hepatic injury and chronic liver disease.

Parameters and Morphological Changes of Erythrocytes and Platelets of COVID-19 Subjects: A Longitudinal Cohort Study

Purpose

Information about dynamic changes occurring in the parameters and morphology of erythrocytes and platelets during the coronavirus disease 2019 (COVID-19) infection and convalescence is scarce. To explore potential associations between dynamic erythrocyte and platelet parameters, morphological changes, and the course or severity of the disease is essential.

Patients and Methods

From January 17th, 2020, to February 20th, 2022, we followed up on 35 patients with non-severe and 11 patients with severe COVID-19 following their discharge. We collected clinical features, dynamic complete blood count (CBC), and peripheral blood smears (PBS) and analyzed parameter and morphological changes of erythrocytes and platelets depending on the course or severity of the disease. The course of the disease included four periods, namely onset (T1), discharge (T2), 1-year follow-up (T3), and 2-year follow-up (T4).

Results

Red blood cell (RBC) counts and hemoglobin were the lowest in T2, followed by T1, and lower in T1 and T2 than in T3 and T4. Inversely, the red blood cell distribution width (RDW) was the highest in T2, followed by T1, and higher than in T3 and T4. Compared to non-severe patients, the platelet of severe patients was lower in T1 and T2. In contrast, the mean platelet volume (MPV) and platelet distribution width (PDW) tended to be higher in severe patients. Similarly, anisocytosis was more common in peripheral blood smears at early stages and in severe patients. Finally, large platelets were more common in severe patients.

Conclusion

Anisocytosis of erythrocytes and large platelets are found in patients with severe COVID-19, these changes may help primary hospitals to identify patients with a high risk of severe COVID-19 at an early stage.

Red cell distribution width and Glasgow coma scale score as predictors of in-hospital mortality in maintenance hemodialysis patients diagnosed with spontaneous intracerebral hemorrhage

Glasgow Coma Scale (GCS) score is being widely used as a useful predictor to investigate patients with head injury. High red cell distribution width (RDW) values have been independently associated with mortality and poor neurological outcome. However, there are few data available for Spontaneous Intracerebral Hemorrhage (SIH) in maintenance hemodialysis (MHD) patients. This study aimed to evaluate the prognostic value of the combined measurement of RDW and GCS score in MHD patients with SIH. We retrospectively studied 46 MHD patients who was admitted to our hospital for nontraumatic SIH from October 2014 to May 2020. Data including demographic information, cause of renal failure, comorbidities at ESRD, clinical and laboratory parameters at admission were collected from medical records. Univariate and multivariate Logistic regression analysis were performed to identify independent risk factors of the in-hospital Mortality in Hemodialysis Patients with SIH. The receiver operating characteristic curve (ROC) and areas under the curve (AUCs) were determined. The sensitivity and specificity of independent risk factors were calculated for a range of different cutoff points. A total of 46 patients were enrolled in the study. The in-hospital mortality rate was 69.57%. We divided subjects into 2 groups based on the clinical outcomes. Compared with survivors (n = 14), non-survivors (n = 32) had longer hemodialysis vintage (P = .017), lower GCS score (P < .001), higher hemoglobin (Hb) (P = .032) and RDW (P = .009). In multivariate logistic regression analysis, GCS score (OR 0.719, 95% CI 0.546-0.946; P = .018) and RDW (OR 4.549, 95% CI 1.243-0.946; P = .018) were independent risk factors of in-hospital mortality in MHD patients with SIH. The area under the ROC curve (AUC) for GCS score was 0.849 (95% CI 0.729-0.970) while that for RDW was 0.743 (95% CI 0.596-0.891). The AUC for the combined prediction was 0.916 (95% CI 0.828-1.000), with a sensitivity of 90.63% and a specificity of 88.46%. In conclusion, high RDW and low GCS score were useful and independent poor prognostic markers for in-hospital mortality of MHD patients with SIH.

Distribution Width of Red Blood Cells and Related Factors Among Patients with End-Stage Renal Disease in Addis Ababa, Ethiopia

Background

RDW is critical to the clinical diagnosis and progression of ESRD. There is currently little data on the relationship between RDW and ESRD in sub-Saharan Africa. Because of this, the present study evaluates RDW in patients with ESRD and associated factors in Addis Ababa, Ethiopia.

Methods

The hospital-based cross-sectional study design was conducted on a total of 83 patients. RDW, MCV, SCR, BUN, GFR, FBS and serum albumin were determined. Blood pressure (mmHg), weight (kg), height (m), MUAC (cm) and BMI (kg/m2) were also measured. Data entry was via Epi-data version 3.4 and analyzed with SPSS version 26.0. A multivariate logistic regression analysis with a p-value < 0.05 at a 95% confidence interval was used to identify the associated factors of RDW.

Results

A total of 83 ESRD patients participated, with a response rate of 95.4%. RDW ranged from 15.5% to 23.6% with a mean of 17.40% + 1.46%. Anisocytosis was present in 98.8% of patients. Of 83 patients, 66.3% were hypertensive, 20.5% had diabetes, and the remaining 13.3% had other conditions (glomerulonephritis and peripheral vascular disease). The mean GFR value was 5.20 mL/min/1.73 + 1.58. RDW showed a significant association with GFR (AOR: 4.6, 95% CI [1.27, 20.74], P = 0.047), alcohol consumption (AOR: 13.4, P = 0.012, 95% CI [1.97, 22.62]), recurrent kidney disease (AOR=25.6, P=0.016, 95% CI [1.85, 53.71]) and use of medication (AOR=00.2, P=0.044), 95% CI [0.03, 0.95]).

Conclusion

RDW showed a significant association with GFR, recurrent kidney disease, alcohol consumption, and medication use in hemodialysis-dependent ESRD patients. The mechanisms of RDW disruption in ESRD patients need further investigation.

Prognostic Impact of Red Cell Distribution Width on the Development of Contrast-Induced Nephropathy, Major Adverse Cardiac Events, and Mortality in Coronary Artery Disease Patients Undergoing Percutaneous Coronary Intervention

Red cell distribution width (RDW) serves as an independent predictor towards the prognosis of coronary artery disease (CAD) in patients undergoing percutaneous coronary intervention (PCI). A systematic search of databases such as PubMed, Embase, Web of Science, and Cochrane library was performed on October 10th, 2019, to elaborate the relationship between RDW and in hospital and long term follow up, all-cause and cardiovascular mortality, major adverse cardiac events (MACE) and development of contrast-induced nephropathy (CIN) in patients with CAD undergoing PCI. Twenty-one studies qualified this strict selection criterion (number of patients = 56,425): one study was prospective, and the rest were retrospective cohorts. Our analysis showed that patients undergoing PCI with high RDW had a significantly higher risk of in-hospital all-cause mortality (OR 2.41), long-term all-cause mortality (OR 2.44), cardiac mortality (OR 2.65), MACE (OR: 2.16), and odds of developing CIN (OR: 1.42) when compared to the patients with low RDW. Therefore, incorporating RDW in the predictive models for the development of CIN, MACE, and mortality can help in triage to improve the outcomes in coronary artery disease patients who undergo PCI.

Red blood cell distribution width as a predictor of mortality among patients regularly visiting the nephrology outpatient clinic

The association between increased red blood cell distribution width (RDW) and mortality among patients treated on an outpatient basis in the nephrology outpatient clinic is unclear. Therefore, our study aimed to investigate the association between baseline and time-averaged RDW and mortality risk in patients treated in our nephrology outpatient clinic. Our multi-center retrospective analysis was based on data of 16,417 outpatient nephrology patients with available baseline renal function and RWD values. The median baseline RDW was 13.0% (range, 10.0–32.1%). The high-RDW group was defined as the top quartile (≥ 13.8%, n = 4302). The crude mortality rate was 15.0% (n = 1806) at a median follow-up of 127.5 months. From the results of the multivariate Cox proportional hazards regression model adjusted for covariates, including eGFR, hemoglobin, and factors of anemia treatment, patients with a high time-averaged RDW had increased mortality risk (adjusted hazard ratio, 1.505; 95% confidence interval, 1.326–1.708; P < 0.001), irrespective of sex, presence of anemia, and chronic kidney disease, except in individuals aged < 45 years. Thus, increased baseline and time-averaged RDW were significantly associated with increased mortality in patients aged > 45 years treated on an outpatient basis in the nephrology clinic.

Microalbuminuria After Kidney Transplantation Predicts Cardiovascular Morbidity

Background: Microalbuminuria is a well-characterized marker of kidney malfunction, both in diabetic and non-diabetic populations, and is used as a prognostic marker for cardiovascular morbidity and mortality. A few studies implied that it has the same value in kidney transplanted patients, but the information relies on spot or dipstick urine protein evaluations, rather than the gold standard of timed urine collection.

Methods: We revisited a cohort of 286 kidney transplanted patients, several years after completing a meticulously timed urine collection and assessed the prevalence of major cardiovascular adverse events (MACE) in relation to albuminuria.

Results: During a median follow up of 8.3 years (IQR 6.4–9.1) 144 outcome events occurred in 101 patients. By Kaplan-Meier analysis microalbuminuria was associated with increased rate of CV outcome or death (p = 0.03), and this was still significant after stratification according to propensity score quartiles (p = 0.048). Time dependent Cox proportional hazard analysis showed independent association between microalbuminuria and CV outcomes 2 years following microalbuminuria detection (HR 1.83, 95% CI 1.07–2.96).

Conclusions: Two years after documenting microalbuminuria in kidney transplanted patients, their CVD risk was increased. There is need for primary prevention strategies in this population and future studies should address the topic.

Red Blood Cell Distribution Width Is Associated with Deterioration of Renal Function and Cardiovascular Morbidity and Mortality in Patients with Diabetic Kidney Disease

We sought to investigate the possible association between Red Blood Cell Distribution Width (RDW), vascular calcification, oxidative stress and renal function and all-cause/cardiovascular (CV) mortality, CV events and progression of kidney disease in a cohort of patients with Diabetic Kidney Disease (DKD). Carotid intima media thickness (cIMT) and oxidized low-density cholesterol were measured in 104 Type 2 Diabetes Mellitus (T2DM) patients with established DKD, distributed in all five stages of kidney disease and 38 diabetics with normal renal function. All patients were followed for 7 years with end-points all-cause and CV mortality, CV events and progression to End-Stage Renal Disease (ESRD). RDW was positively correlated with diabetes duration (r = 0.19, p = 0.023) and albuminuria (r = 0.29, p = 0.002). Multivariate regression analysis revealed that RDW was a strong, independent predictor of cIMT value (β = 0.031, p = 0.012). Kaplan-Meier curves and Cox proportional hazard models revealed that after adjustment for several cofounders, RDW was a significant and independent predictor for all-cause mortality, CV mortality, CV event and progression to ESRD (HR 1.75, p = 0.001, HR 2.03, p = 0.001, HR = 1.66, p < 0.0001 and HR 2.14, p = 0.001 respectively). RDW predicts mortality, CV events and deterioration of renal function in DKD, probably reflecting atherosclerosis.

Red blood cell distribution width and mortality and hospitalizations in peritoneal dialysis patients

BACKGROUND

Red blood cell distribution width (RDW) is found to be associated with different types of anemia and has recently been studied as a prognostic marker of mortality in hemodialysis patients. However, the relationship of RDW with mortality and hospitalization rate in peritoneal dialysis (PD) patients is less known.

METHODS

Among 14 323 incident PD patients between 2007 and 2011 in the USA, we examined the relationship of baseline and time-varying RDW with the risk of mortality and time to first hospitalization using adjusted Cox models. In addition, we examined the relationship of baseline RDW and hospitalization rate using an adjusted negative-binomial regression model. Sensitivity analyses included competing risk models and subgroup analyses.

RESULTS

The study population comprised patients 56 ± 16 years of age, including 43% females, 23% African Americans and 62% diabetics, with a mean RDW of 15.3 ± 1.6%. In models adjusted for clinical characteristics and laboratory parameters, RDW exhibited an incremental relationship with the mortality risk, where RDW ≥16.5% had a 40% and 69% higher risk of death in baseline and time-varying analyses, respectively, compared with an RDW of 14.5-15.5%. Moreover, higher baseline RDW ≥16.5% was also associated with a higher risk of time to first hospitalization {hazard ratio 1.22 [95% confidence interval (CI) 1.14-1.29]} and a higher rate of hospitalizations [incidence rate ratio 1.16 (95% CI 1.09-1.23)]. These results were consistent across numerous sensitivity analyses.

CONCLUSIONS

Higher RDW is associated with a higher risk of mortality and hospitalizations among incident PD patients. Further studies are needed to examine the mechanism behind RDW and adverse outcomes.

Red cell distribution width and renal outcome in patients with non-dialysis-dependent chronic kidney disease

Higher red cell distribution width (RDW) has been reported to predict mortality among patients with various diseases, including chronic kidney disease (CKD). However, whether RDW is associated with renal outcome remains unclear. We investigated the relationship between RDW and renal outcome in patients with non-dialysis-dependent CKD (NDD-CKD). This prospective, observational study of patients with CKD was conducted at a single nephrology department. First, we performed regression analyses for the decline in estimated glomerular filtration rate (eGFR) during the first 3 months of observation to determine its short-term association with RDW. Next, we categorized baseline RDW into two groups by its median (13.5%) and performed Cox regression analyses to investigate whether higher RDW was an independent predictor of renal outcomes defined as a composite of the initiation of dialysis and doubling of the serum creatinine concentration. Furthermore, we repeated the analyses to confirm whether the transition of the RDW category during the first 3 months would also predict renal outcomes. We enrolled 703 patients. Baseline RDW showed a non-linear association with the eGFR decline during the first 3 months, with a greater negative correlation at the lower end of the RDW distribution. Over a median follow-up of 1.8 years, 178 patients (25.3%) reached the renal endpoint. Multivariable Cox regression analyses showed that patients with higher RDW had a higher risk of developing renal outcomes (adjusted hazard ratio [HR]: 1.47, 95% confidence interval [CI]: 1.05–2.07) than did those with lower RDW. Furthermore, patients with sustained, higher RDW demonstrated a significantly higher risk than did those with consistently lower RDW (adjusted HR: 1.65, 95% CI: 1.02–2.67). In conclusion, higher RDW was independently associated with worse renal outcome in patients with NDD-CKD. RDW could be an additional prognostic marker of the progression of CKD.

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.

Red cell distribution width as a significant indicator of medication and prognosis in type 2 diabetic patients

Whether red cell distribution width (RDW) can be a potential indicator for diabetic nephropathy (DN) is unknown. A total of 809 type 2 diabetes mellitus (T2D) patients were divided into 4 groups according to the quartiles (Q) of the RDW (%): Q1 ≤ 12.4 (n = 229), 12.4 < Q2 ≤ 12.9 (n = 202), 12.9 < Q3 < 13.5 (n = 168), Q4 ≥ 13.5 (n = 210). Results showed that the levels in Q4 group was higher in age, disease duration, systolic blood pressure, blood urea nitrogen, creatinine, uric acid and proteinuria but lower in hemoglobin, serum albumin and glycosylated hemoglobin compared to Q1 group. Furthermore, the incidences of DN, diabetic peripheral neuropathy, hypertension and coronary heart disease in the Q3 or Q4 group were higher compared to Q1 group. Medications including calcium channel blockers and antiplatelet therapy also showed higher frequencies in Q3 or Q4 group compared to Q1. Logistic regression indicated that the antiplatelet therapy (OR = 2.065), hypertension (OR = 2.819), creatinine (OR = 4.473) and proteinuria (OR = 2.085) were positively associated with level of Q4 group, but higher hemoglobin (OR = 0.021) and serum Ca²⁺ (OR = 0.178) were negatively associated with Q4. This data suggest that high level of RDW in T2D patients indicates a higher risk and a poor prognosis for DN.

Red blood cell distribution width predicts two-hours plasma glucose levels during OGTT

OBJECTIVE

Red blood cell distribution width (RDW) is a numerical measure, reported as part of a standard complete blood count, usually employed for differential diagnosis of anemic state. Some lines of evidence demonstrate that RDW associates with type 2 diabetes incidence and its complications. To further explore the role of RDW as predictor of abnormal glucose metabolism, we have analyzed the relationship between RDW and 2-hours plasma glucose concentration during an oral glucose tolerance test (OGTT).

METHODS

Forty-five outpatients were enrolled for the present study. Participants underwent 75 g OGTT and measurements of hematological parameters. Cardiovascular disease risk factors (blood pressure, blood lipids, cigarette smoking, obesity) were evaluated by routine methods.

RESULTS

In simple regression analysis 2-hours post-load glucose was directly associated with age (r = 0.36, p = 0.01), fasting glucose levels (r = 0.40, p = 0.002) and RDW (r = 0.31, p = 0.037). In multiple regression analysis fasting glucose, RDW, triglycerides and age significantly and independently predicted 2-hours plasma glucose (p <  0.01 for all coefficients).

CONCLUSION

The present findings demonstrate that RDW associates with plasma glucose concentration after a 75-g oral glucose tolerance test. Our results highlight the role of RDW as predictor of glucose metabolism disturbance.

The accuracy of combined use of troponin and red cell distribution width in predicting mortality of patients with acute pulmonary embolism

BACKGROUND

Cardiac troponins and red cell distribution width (RDW) are associated with increased mortality in acute pulmonary embolism (PE). In this study, we aimed to investigate the accuracy of the combined use of troponin and RDW in predicting short-term mortality in acute PE patients.

METHODS

The data of 201 patients with the diagnosis of acute PE were retrospectively analyzed. We obtained troponin-RDW scores (TR scores) using a combination of troponin and RDW values, and then evaluated this score's accuracy in predicting mortality in patients with acute PE.

RESULTS

The mean participant age was 68 ± 16 years, and 52 % of patients were female. Fifteen (7.4 %) patients died during the first month. Patients classified as high-risk according to TR scores were older (72 ± 15 vs. 66 ± 15 years, p = 0.005), and they had higher heart rates (101 ± 20 vs. 90 ± 15 beat/min, p < 0.001) and respiratory rates (23 ± 4 vs. 21 ± 3 breath/min, p = 0.001). In multivariate analysis, TR (odds ratio [OR] 4.93, 95 % confidence interval [CI] 1.13-21.38, p = 0.033) and simplified pulmonary embolism severity index (sPESI) scores (OR 3.78, 95 % CI 1.71-8.37, p = 0.002) were independent predictors of 30-day mortality. For 30-day mortality, the TR score had a slightly lower sensitivity (87 % vs. 93 %), but a higher specificity (69 % vs. 52 %) compared to the sPESI score.

CONCLUSION

The TR score is easy to calculate, and it may be used to predict early mortality in patients with acute PE.

Red cell distribution width is associated with albuminuria in adults with familial Mediterranean fever

Systematic inflammation, enhanced oxidative stress, and endothelial dysfunction are important for evolution and progression of renal damage, and they cause an increase in red cell distribution width (RDW). Familial Mediterranean fever (FMF) patients who are in the attack-free period and its relation with albuminuria and performance on assessment of microalbuminuria. One hundred and seventy-seven patients who had been diagnosed in accordance with Tel-hoshmer criteria and were in the attack-free period, and 143 age- and sex-matched healthy individuals were enrolled in our study. RDW values of FMF patients were higher compared with those of the controls (13.85 ± 1.07 and 13.15 ± 0.91, respectively; p < 0.0001). RDW values of FMF patients with microalbuminuria were higher compared with those of FMF patients with normoalbuminuria and the control group (p = 0.002 and p < 0.0001, respectively). RDW values of FMF patients with normoalbuminuria were higher compared with those of the control group (p < 0.0001). We have showed RDW levels are positively correlated with albuminuria (r = 0.185, p = 0.014). When assessing microalbuminuria with RDW in the patients, a cutoff value of 13.85 with sensitivity of 60%, specificity of 62%, and p = 0.002 (area under curve: 0.651, 95% confidence interval 0.563-0.738), was observed according to receiver-operating characteristic curve analysis. Among the various variables associated with albuminuria in multivariate logistic regression analyses, RDW remained an independent predictor of albuminuria (95% confidence interval 0.479-0.942, p = 0.021). RDW may be associated with albuminuria in FMF patients and it can be a predictor of microalbuminuria.

Association between the Red Cell Distribution Width and Vasospastic Angina in Korean Patients

PURPOSE

The association between the red cell distribution width (RDW) and vasospastic angina (VSA) has not been elucidated. We investigated the association of the RDW with the incidence and angiographic subtypes of VSA in Korean patients.

MATERIALS AND METHODS

A total of 460 patients who underwent intracoronary ergonovine provocation tests were consecutively enrolled and classified into two groups: the VSA group (n=147, 32.0%) and non-VSA group (n=313, 68.0%). The subjects were classified into 3 subgroups (tertiles) according to the baseline level of RDW assessed before the angiographic provocation test.

RESULTS

The VSA group had a higher RDW than the non-VSA group (12.9±0.8% vs. 12.5±0.7%, p=0.013). The high RDW level demonstrated an independent association with the high incidence of VSA [second tertile: hazard ratio (HR) 1.96 (1.13-2.83), third tertile: HR 2.33 (1.22-3.47), all p<0.001]. Moreover, the highest RDW tertile level had a significant association with the prevalence of the mixed-type coronary spasm [HR 1.29 (1.03-1.59), p=0.037].

CONCLUSION

The high level of RDW was significantly associated with the prevalence of VSA and the high-risk angiographic subtype of coronary spasm, suggesting that a proactive clinical investigation for VSA could be valuable in Korean patients with an elevated RDW.

Red cell distribution width and end-organ damage in patients with systo-diastolic hypertension

INTRODUCTION

Both end-organ damage and high red cell distribution width (RDW) values are associated with adverse cardiovascular events, inflammatory status, and neurohumoral activation in hypertensive disease and in the general population. In this study, we investigated the relationship between RDW and end-organ damage in hypertensive patients.

MATERIAL AND METHODS

The 446 systo-diastolic hypertensive patients included in the study received 24-hour ambulatory blood pressure monitoring. Left ventricular mass index, glomerular filtration rate, and microalbuminuria were measured to identify end-organ damage. High-sensitivity C-reactive protein (hs-CRP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels of all patients were also examined.

RESULTS

The mean age of the participants was 49.96 ±11.04 years. The mean RDW was 13.06 ±1.05%. Red cell distribution width was positively correlated with left ventricular myocardial index (LVMI), urinary albumin, hs-CRP, and NT-proBNP (r = 0.298, p < 0.001; r = 0.228, p < 0.001; r = 0.337, p < 0.001; r = 0.277, p < 0.001, respectively), while RDW was negatively correlated with eGFR (r = -0.153, p < 0.001). Additionally, while there was a positive correlation between RDW and 24-h systolic blood pressure, no correlation was found between RDW and 24-h diastolic blood pressure (r = 0.132, p = 0.006 and r = 0.017, p = 0.725, respectively). Multiple linear regression analysis revealed that RDW levels were independently associated with eGFR, LVMI, and severity of albuminuria (β = 0.126, p = 0.010; β = -0.149, p = 0.002; β = 0.114, p = 0.035).

CONCLUSIONS

High RDW levels in systo-diastolic hypertensive patients were found to be an independent predictor of end-organ damage.

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

BACKGROUND AND AIM

We investigated the utility of the preprocedural red cell distribution width (RDW) for predicting contrast-induced acute kidney injury (CI-AKI) in patients with ST-segment-elevation myocardial infarction (STEMI) who underwent a primary percutaneous coronary intervention.

MATERIALS AND METHODS

A total of 630 consecutive patients who were routinely referred to coronary angiography for STEMI were included in the present study.

RESULTS

CI-AKI was observed in 79 patients (12.5%). The RDW, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and the mean platelet volume were significantly higher in the CI-AKI group than in the non-CI-AKI group (P<0.001, P=032, P=0.025, and P=0.039, respectively). Serum total bilirubin and direct bilirubin levels were not different among the study groups. Using multivariate logistic regression analysis, we found that left ventricular ejection fraction [odds ratio (OR)=0.972, 95% confidence interval (CI) 0.945-0.998, P=0.033], estimated glomerular filtration rate (OR=0.970, 95% CI 0.959-0.981, P<0.001), contrast volume (OR=1.007, 95% CI 1.002-1.012, P=0.009), and RDW (OR=1.406, 95% CI 1.120-1.792, P=0.005) were independent predictors of CI-AKI.

CONCLUSION

Red blood cell distribution width, an inexpensive and easily measurable laboratory variable, is associated independently with the development of CI-AKI. Our data suggest that RDW may be a useful marker in CI-AKI risk stratification.

Red Cell Distribution Width and Mortality in Hemodialysis Patients

BACKGROUND

Red cell distribution width (RDW) is an index of red blood cell volume variability that has historically been used as a marker of iron deficiency anemia. More recently, studies have shown that elevated RDW is associated with higher mortality risk in the general population. However, there is lack of data demonstrating the association between RDW and mortality risk in hemodialysis (HD) patients. We hypothesized that higher RDW is associated with higher mortality in HD patients.

STUDY DESIGN

Retrospective observational study using a large HD patient cohort.

SETTING & PARTICIPANTS

109,675 adult maintenance HD patients treated in a large dialysis organization from January 1, 2007, to December 31, 2011.

PREDICTOR

Baseline and time-varying RDW, grouped into 5 categories: <14.5%, 14.5% to <15.5%, 15.5% to <16.5%, 16.5% to <17.5%, and ≥17.5%. RDW of 15.5% to <16.5% was used as the reference category.

OUTCOME

All-cause mortality.

RESULTS

Mean age of study participants was 63±15 (SD) years and the study cohort was 44% women. In baseline and time-varying analyses, there was a graded association between higher RDW and incrementally higher mortality risk. Receiver operating characteristic, net reclassification analysis, and integrated discrimination improvement analyses demonstrated that RDW is a stronger predictor of mortality as compared with traditional markers of anemia, such as hemoglobin, ferritin, and iron saturation values.

LIMITATIONS

Lack of comprehensive data that may be associated with both RDW and HD patient outcomes, such as blood transfusion data, socioeconomic status, and other unknown confounders; therefore, the possibility of residual confounding could not be excluded. Also, lack of information for cause of death; thus, cardiovascular mortality outcomes could not be examined.

CONCLUSIONS

In HD patients, higher RDW is associated with incrementally higher mortality risk. RDW is also a stronger predictor of mortality than traditional laboratory markers of anemia. Further studies are needed to determine the mechanisms underlying the association between RDW and mortality.

Association between Red Blood Cell Distribution Width and Coronary Artery Calcification in Patients Undergoing 64-Multidetector Computed Tomography

Background and Objectives

The red blood cell distribution width (RDW) has been found to be associated with cardiovascular morbidity and mortality. The objective of this study was to determine whether the RDW measures are associated with the coronary artery calcification score (CACS) in patients who did not present with obvious coronary heart disease (CHD).

Subjects and Methods

A total of 527 consecutive patients with a low to intermediate risk for CHD but without obvious disease were enrolled in this study. The study subjects underwent coronary computerized tomography angiography and CACS was calculated. The patients were divided into two groups based on CACS: Group I (CACS≤100) and Group II (CACS>100). The two groups were compared in terms of classic CHD risk factors and haematological parameters, particularly the RDW.

Results

Group I patients were younger than Group II patients. The Framingham risk score (FRS) in patients of Group II was significantly higher than that in patients of Group I. Group II patients had significantly elevated levels of haemoglobin, RDW, neutrophil count, and neutrophil/lymphocyte ratio compared with Group I patients. CACS was correlated with age, RDW, and ejection fraction. In the multivariate analysis, age, RDW, and FRS were independent predictors of CACS. Using the receiver-operating characteristic curve analysis, a RDW value of 13.05% was identified as the best cut-off for predicting the severity of CACS (>100) (area under the curve=0.706).

Conclusion

We found that the RDW is an independent predictor of the CACS, suggesting that it might be a useful marker for predicting CAD.

Red blood cell distribution width: A simple parameter with multiple clinical applications

The red blood cell distribution width (RDW) is a simple and inexpensive parameter, which reflects the degree of heterogeneity of erythrocyte volume (conventionally known as anisocytosis), and is traditionally used in laboratory hematology for differential diagnosis of anemias. Nonetheless, recent evidence attests that anisocytosis is commonplace in human disorders such as cardiovascular disease, venous thromboembolism, cancer, diabetes, community-acquired pneumonia, chronic obstructive pulmonary disease, liver and kidney failure, as well as in other acute or chronic conditions. Despite some demographic and analytical issues related to the routine assessment that may impair its clinical usefulness, an increased RDW has a high negative predictive value for diagnosing a variety of disorders, but also conveys important information for short- and long-term prognosis. Even more importantly, the value of RDW is now being regarded as a strong and independent risk factor for death in the general population. Although it has not been definitely established whether an increased value of RDW is a risk factor or should only be considered an epiphenomenon of an underlying biological and metabolic imbalance, it seems reasonable to suggest that the assessment of this parameter should be broadened far beyond the differential diagnosis of anemias. An increased RDW mirrors a profound deregulation of erythrocyte homeostasis involving both impaired erythropoiesis and abnormal red blood cell survival, which may be attributed to a variety of underlying metabolic abnormalities such as shortening of telomere length, oxidative stress, inflammation, poor nutritional status, dyslipidemia, hypertension, erythrocyte fragmentation and alteration of erythropoietin function. As such, the aim of this article is to provide general information about RDW and its routine assessment, to review the most relevant implications in health and disease and give some insights about its potential clinical applications.

The evaluation of red cell distribution width in chronic hemodialysis patients

Background. Red cell distribution width (RDW) has been used as a marker of iron deficiency; however, it is accepted as a marker of cardiovascular survival. We aimed to study RDW levels in hemodialysis (HD) patients and the association between RDW and inflammatory, nutritional, and volume markers. Methods. We included 296 HD patients with sufficient iron storage and without anemia or hypervolemia. We grouped patients into four groups according to clinical parameters, albumin, and C-reactive protein (CRP). Results. The lowest RDW levels were found in group 1 (13.2%). Although RDW of group 2 was higher than that of group 1, it was still in normal range (14.7% versus 13.2%, P = 0.028). RDW levels of groups 3 (17.8%) and 4 (18.5%) were significantly higher than those of groups 1 and 2 and above normal range. A positive correlation was detected between RDW and HD duration, interdialytic weight gain (IDWG), serum phosphate, and CRP levels and a negative correlation was detected with serum albumin. HD duration, CRP, IDWG, and serum albumin have been found as independent predictors of RDW elevation. Conclusions. Results of the present study reflect adverse effects of inflammation, malnutrition, and excess IDWG on RDW elevation in an HD study cohort with sufficient iron storage and without anemia and hypervolemia.

Red blood cell distribution width and diabetes-associated complications

AIM

Red blood cell distribution width (RDW) is a marker of cardiovascular morbidity and mortality. However, there is little data on the relationship between RDW and diabetes-associated complications. The aim was to investigate whether there is any association between RDW, nephropathy, neuropathy and peripheral arterial disease (PAD) in a type 2 diabetic population.

METHODS

This study included 196 diabetic patients with proliferative diabetic retinopathy. All subjects were investigated for diabetic nephropathy, diabetic neuropathy and PAD. Participants underwent 24-h blood pressure monitoring and were analysed for markers of the metabolic syndrome, inflammation, and insulin resistance.

RESULTS

57% of the participants had diabetic nephropathy, 46% had diabetic neuropathy while 26% had PAD. No significant association was found between RDW, diabetic neuropathy and PAD (p=NS). However, RDW was strongly associated with diabetic nephropathy (p=0.006), even following adjustment for potential confounding variables. Multivariate logistic regression analysis showed RDW (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.15-2.35, p=0.006), estimated glomerular filtration rate (OR 0.98, 95% CI 0.96-0.99, p<0.001), night-time diastolic blood pressure (OR 1.07, 95% CI 1.03-1.11, p=0.001) and erythrocyte sedimentation rate (OR 1.03, 95% CI 1.004-1.05, p=0.019) to be independently associated with diabetic nephropathy.

CONCLUSIONS

This is the first study to report lack of association between RDW, neuropathy and PAD in subjects with type 2 diabetes mellitus. More importantly, RDW was shown to be significantly associated with diabetic nephropathy in a type 2 diabetic population with advanced proliferative retinopathy independent of traditional risk factors, including diabetes duration and glycaemic control.

Red cell distribution width is associated with long-term prognosis in patients with stable coronary artery disease

Background

Data regarding the association between red cell distribution width (RDW) values and mortality in patients with stable coronary artery disease are scarce. We aimed to investigate the link between mortality and RDW in patients with stable coronary artery disease undergoing percutaneous coronary intervention (PCI).

Methods

We analyzed 2550 consecutive patients with stable coronary artery disease who underwent PCI between 2007 and 2011 at our institution. The patients were divided into four groups according to RDW quartiles. The association between the RDW values and the outcomes was assessed using Cox proportional regression analysis after adjusting for clinical, echocardiographic, hemodynamic and laboratory data in the whole population and in subgroups stratified by gender, presence of diabetes, anemia or heart failure.

Results

In the entire population, there was a stepwise relationship between RDW intervals and comorbidities. Patients with the highest RDW values were older and more often burdened with diabetes, heart failure and chronic kidney disease. There was an almost 4-fold increase in mortality during an average of 2.5 years of follow-up between the group of patients with RDW values lower than 13.1% (25^th percentile) and the group with RDW values higher than 14.1% (75^th percentile), (4.3% vs. 17.1%, p < 0.0001). After adjusting for the covariates, RDW remained significantly associated with mortality in the whole cohort (HR-1.23 [95% CI (1.13-1.35), p < 0.0001]) and in the subgroups stratified by gender, age (over and under 75 years), presence of anemia, diabetes, heart failure and chronic kidney disease.

Conclusion

Higher RDW values correspond to higher comorbidity burdens and higher mortality. RDW is an independent predictor of mortality in patients with stable coronary artery disease.

Red cell distribution width identifies cerebral venous sinus thrombosis in patients with headache

BACKGROUND

Diagnosing cerebral venous sinus thrombosis (CVST) in patients referring to emergency service or neurology outpatient unit with complaints of headache is a challenging task. Magnetic resonance (MR) venography is the gold standard, but there are limitations regarding its use.

AIM

To evaluate the validity of red cell distribution width (RDW) in CVST diagnosis in patients presenting with headache.

METHODS

A total of 138 patients comprising 37 patients with CVST and 101 control primer headache cases were included in this retrospective cross-sectional study. Control group consists of hospitalized patients with primary headache. Venous blood hemoglobin (Hb), platelet, mean corpuscular volume (MCV), RDW, fibrinogen, and vitamin B12 levels of the patients were recorded at the first referral. Diagnosis of CVST was established by MR venography.

RESULTS

The RDW ratio of patients with a diagnosis of CVST was significantly higher than that in patients with primary headache (15.3 ± 1.4 vs 13.3 ± 0.5; P <.0001). Fibrinogen and vitamin B12 levels were not significantly different between the 2 groups. In a total of 11 patients, there was more than 1 thrombosis. In 21 of the patients with CVST, gene mutation was detected. There was no significant difference between the patients with and without mutations regarding RDW values. Diagnostic validity of RDW was found to be excellent in differentiating patients with CVST and primary headache (area under the curve = 0.996; 95% CI: 0.990-1.000). Optimum RDW cutoff value was determined as 14.1% (sensitivity: 91.9%, specificity: 99%, positive predictive value: 92.8, negative predictive value: 0.082).

CONCLUSION

We suppose that among patients presenting with the complaint of headache, RDW value may lead to diagnose CVST.

Elevated red cell distribution width is associated with advanced fibrosis in NAFLD

Background/Aims

The red-blood-cell distribution width (RDW) is a newly recognized risk marker in patients with cardiovascular disease, but its role in nonalcoholic fatty liver disease (NAFLD) has not been well defined. The aim of the present study was to determine the association between RDW values and the level of fibrosis in NAFLD according to BARD and FIB-4 scores.

Methods

This study included 24,547 subjects who had been diagnosed with NAFLD based on abdominal ultrasonography and questionnaires about alcohol consumption. The degree of liver fibrosis was determined according to BARD and FIB-4 scores. The association between RDW values and the degree of fibrosis in NAFLD was analyzed retrospectively.

Results

After adjusting for age, hemoglobin level, mean corpuscular volume, history of hypertension, history of diabetes, and high-sensitivity C-reactive protein, the RDW values were 12.61±0.41% (mean±SD), 12.70±0.70%, 12.77±0.62%, 12.87±0.82%, and 13.25±0.90% for those with BARD scores of 0, 1, 2, 3, and 4, respectively, and 12.71±0.72%, 12.79±0.66%, and 13.23±1.52% for those with FIB-4 scores of <1.30, 1.31-2.66, and ≥2.67, respectively (P<0.05). The prevalence of advanced fibrosis (BARD score of 24 and FIB-4 score of ≥1.3) increased with the RDW [BARD score: 51.1% in quartile 1 (Q1) vs. 63.6% in Q4; FIB-4 score: 6.9% in Q1 vs. 10.5% in Q4; P<0.001]. After adjustments, the odds ratio of having advanced fibrosis for those in Q4 compared to Q1 were 1.76 (95%CI=1.55-2.00, P<0.001) relative to BARD score and 1.69 (95%CI=1.52-1.98, P<0.001) relative to FIB-4 score.

Conclusions

Elevated RDW is independently associated with advanced fibrosis in NAFLD.

Renal function is independently associated with red cell distribution width in kidney transplant recipients: a potential new auxiliary parameter for the clinical evaluation of patients with chronic kidney disease

Red cell distribution width (RDW), a measure of heterogeneity in the size of circulating erythrocytes, reportedly predicts mortality. Similarly to RDW, impaired renal function is also associated with inflammation and protein-energy wasting. This study assessed if renal function is associated with RDW independent of relevant confounders in stable kidney transplant recipients. We examined the association between RDW and estimated glomerular filtration rate (eGFR) in a cohort of 723 prevalent kidney transplanted recipients who were not receiving erythropoietin-stimulating agents. Associations were examined in regression models adjusted for age, sex, comorbidity, blood haemoglobin, iron indices, markers of nutritional status and inflammation, markers of bone and mineral metabolism and the use of immune suppressants. Lower eGFR was significantly associated with higher RDW (r = -0·382, P < 0·001). This association remained highly significant even after multivariate adjustments where 10 ml/min decrease in the eGFR was significantly associated with an increase of the RDW values (B10 ml/min decrease  =  0·078; 95% confidence interval: 0·044-0·111). The results were consistent in subgroups of patients with different levels of haemoglobin, chronic kidney disease status and various markers of inflammation and iron status. Lower eGFR is associated with higher RDW, independent of comorbidity, iron deficiency, inflammation and nutritional status in kidney transplant recipients.

Relation of coronary collateral circulation with red cell distribution width in patients with non-ST elevation myocardial infarction

OBJECTIVES

We aimed to investigate the relationship between red cell distribution width (RDW) value and coronary collateral circulation (CCC) in patients with non-ST elevation myocardial infarction (NSTEMI).

METHODS

The study population consisted of 322 consecutive patients with NSTEMI. The patients were classified into impaired CCC (group 1, Rentrop grades 0-1) or good CCC (group 2, Rentrop grades 2-3). Baseline RDW was measured as part of the automated complete blood count.

RESULTS

The RDW values were significantly higher in patients with impaired CCC than in those with good CCC (17.2 ± 2.3 vs 14.5 ± 2.5, P < .001). In multivariate logistic regression analysis, RDW (odds ratio: 1.52, 95% confidence interval: 1.30-1.78, P < .001), baseline creatine kinase MB (CK-MB), and absence of preinfarction angina were found to be the independent predictors of impaired CCC. In receiver-operating characteristic curve analysis, the RDW value >15.5 yielded an area under curve value of 0.783, with 77% sensitivity and 73% specificity.

CONCLUSIONS

Our study results demonstrated that, high RDW, high CK-MB, and absence of preinfarction angina were found to be independent predictors of impaired CCC.

Red cell distribution width and risk of peripheral artery disease: Analysis of National Health and Nutrition Examination Survey 1999–2004

Red cell distribution width (RDW) is an independent predictor of the 10-year estimated risk of coronary heart disease (CHD) events. However, RDW’s association with peripheral artery disease (PAD) – a CHD risk equivalent – has not been evaluated to date. In this cross-sectional study, we examined 6950 participants of the National Health and Nutrition Examination Survey, 1999–2004. PAD was defined as an ankle–brachial index below 0.9 ( n = 618). RDW was divided into quartiles (Q) (Q1: ≤ 12.2; Q2: 12.3–12.5; Q3: 12.6–13.0; Q4: ≥ 13.1) and PAD risk was compared across these quartiles using adjusted multivariate logistic regression. A graded increase in prevalent PAD with increasing RDW quartiles was observed (4.2% in Q1 vs 13.9% in Q4; test of trend p < 0.001). Risk of PAD was significantly higher (odds ratio (OR) 1.19, 95% confidence interval (CI): 1.06–1.34; p = 0.003) after adjusting for age, sex, race, body mass index, hypertension, hyperlipidemia, diabetes, smoking, estimated glomerular filtration rate, C-reactive protein, hemoglobin, mean corpuscular volume, and nutritional factors (folate, iron and vitamin B12) deficiencies with each unit (0.1) increase in RDW. Upon receiver-operating characteristics analysis, the predictive accuracy of the American College of Cardiology / American Heart Association (ACC/AHA)-defined PAD screening criteria (for a high-risk population) was 0.657 at best, but improved significantly (0.727) after addition of RDW ( p < 0.0001). In conclusion, higher levels of RDW are independently associated with a higher risk of PAD and can significantly improve the risk prediction beyond that estimated by ACC/AHA-defined PAD screening criteria.