Neutrophil-to-lymphocyte ratio, calprotectin and YKL-40 in patients with chronic obstructive pulmonary disease: correlations and 5-year mortality - a cohort study

NADH Intraperitoneal Injection Prevents Lung Inflammation in a BALB/C Mice Model of Cigarette Smoke-Induced Chronic Obstructive Pulmonary Disease

Cigarette smoke is one of the main factors in Chronic Obstructive Pulmonary Disease (COPD), a respiratory syndrome marked by persistent respiratory symptoms and increasing airway obstruction. Perturbed NAD+/NADH levels may play a role in various diseases, including lung disorders like COPD. In our study, we investigated the preventive effect of NADH supplementation in an experimental model of COPD induced by cigarette smoke extract (CSE). N = 64 mice randomly distributed in eight groups were injected with NADH (two doses of 100 mg/kg or 200 mg/kg) or dexamethasone (2 mg/kg) before being exposed to CSE for up to 9 weeks. Additionally, NADH supplementation preserved lung antioxidant defenses by preventing the functional loss of key enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase, and the expression levels of glutathione (GSH) (n = 4, p < 0.001). It also reduced oxidative damage markers, such as malondialdehyde (MDA) and nitrites (n = 4, p < 0.001). A marked increase in tissue myeloperoxidase activity was assessed (MPO), confirming neutrophils implication in the inflammatory process. The latter was significantly ameliorated in the NADH-treated groups (p < 0.001). Finally, NADH prevented the CSE-induced secretion of cytokines such as Tumor Necrosis Factor alpha (TNF-α), IL-17, and IFN-y (n = 4, p < 0.001). Our study shows, for the first time, the clinical potential of NADH supplementation in preventing key features of COPD via its unique anti-inflammatory and antioxidant properties.

A Diagnostic Nomogram for Predicting Hypercapnic Respiratory Failure in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Purpose

To develop and validate a nomogram for assessing the risk of developing hypercapnic respiratory failure (HRF) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

Patients and Methods

From January 2019 to August 2023, a total of 334 AECOPD patients were enrolled in this research. We employed the Least Absolute Shrinkage and Selection Operator (LASSO) regression and multivariate logistic regression to determine independent predictors and develop a nomogram. This nomogram was appraised by the area under the receiver operating characteristic curve (AUC), calibration curve, Hosmer-Lemeshow goodness-of-fit test (HL test), decision curve analysis (DCA), and clinical impact curve (CIC). The enhanced bootstrap method was used for internal validation.

Results

Sex, prognostic nutritional index (PNI), hematocrit (HCT), and activities of daily living (ADL) were independent predictors of HRF in AECOPD patients. The developed nomogram based on the above predictors showed good performance. The AUCs for the training, internal, and external validation cohorts were 0.841, 0.884, and 0.852, respectively. The calibration curves and HL test showed excellent concordance. The DCA and CIC showed excellent clinical usefulness. Finally, a dynamic nomogram was developed (https://a18895635453.shinyapps.io/dynnomapp/).

Conclusion

This nomogram based on sex, PNI, HCT, and ADL demonstrated high accuracy and clinical value in predicting HRF. It is a less expensive and more accessible approach to assess the risk of developing HRF in AECOPD patients, which is more suitable for primary hospitals, especially in developing countries with high COPD-related morbidity and mortality.

Using complete blood count, serum immunoglobulins G/A/M and complement C3/C4 levels to predict the risk of COPD acute exacerbation: 2-year follow-up in a single-center prospective cohort study

Autoimmunity is present in patients with stable chronic obstructive pulmonary disease (COPD), playing a role in indirect and direct ways. We aimed to explore whether autoimmunity could play a role in COPD exacerbations and construct autoimmunity-related prediction models. This prospective, longitudinal, observational cohort study enrolled 155 patients with acute COPD exacerbations (AECOPD) followed for at least two years. The laboratory parameters, including complete blood count, serum immunoglobulins G/A/M and complement C3/C4 levels, were collected at enrollment. We studied the demographic characteristics, clinical characteristics and laboratory parameters to identify independent risk factors and build predictive models. The results showed that lower lymphocyte count was associated with noninvasive ventilation (NIV) in patients with AECOPD (the odds ratio [OR] 0.25, the 95% confidence interval [CI]: 0.08-0.81, P = 0.02). Lymphocyte count performed well with an area under the curves (AUC) of 0.75 (P < 0.0001, sensitivity: 78.1%, specificity: 62.3%, cutoff value [Cov] ≤ 1.1). The C index, calibration plot, decision curve analysis (DCA) and bootstrap repetitions indicated that this clinical prediction model based on lymphocyte count for NIV in patients with AECOPD performed well. Having prior home oxygen therapy (OR: 2.82, 95% CI: 1.25-6.36, P = 0.013) and higher COPD Assessment Test (CAT) scores (OR: 1.14, 95% CI: 1.03-1.25, P = 0.011) were associated with the increased risk for respiratory failure. For predicting respiratory failure, CAT scores and home oxygen therapy combined had an AUC-ROC of 0.73 (P < 0.0001). This clinical prediction model based on lymphocyte count may help to assist in treatment decisions for NIV in patients with AECOPD. Lower complement C3 seems to be associated with worse outcomes in patients with AECOPD.

Association of Red Cell Index and Hospital Mortality in Chronic Obstructive Pulmonary Disease Patients Admitted to the Intensive Care Unit: A Retrospective Cohort Study

Purpose

This study aims to explore the association between red cell index (RCI) and hospital mortality in Chronic Obstructive Pulmonary Disease (COPD) patients in the intensive care unit.

Patients and Methods

This was a retrospective cohort research. The study included 821 COPD patients. Clinical data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database was conducted. Multivariate logistic regression analysis was used to assess the correlation between RCI and in-hospital mortality. Age, SOFA score, diabetes mellitus, cerebrovascular disease, congestive heart failure and mechanical ventilation were considered for subgroup analysis.

Results

This study comprised 821 patients, of which 16.5% (124/821) suffered hospital mortality. In the multivariate logistic regression model, RCI was positively associated with hospital mortality, each unit increase in RCI was associated with a 3% increase in hospital mortality (odds ratio [OR] =1.03; 95% confidence interval [95CI%] =1.01-1.06). Meanwhile, compare with the lowest RCI group, the highest RCI groups tended to have higher risks of hospital mortality (OR [95% CI] 2.33 [1.27-4.27]). Additionally, subgroup analysis result was persistent among all the groups.

Conclusion

Higher RCI was positively associated with a higher risk of mortality in critically ill patients with COPD. Further investigation is necessary to confirm these findings.

Prognostic Value of Neutrophil to Lymphocyte Ratio for Predicting 90-Day Poor Outcomes in Hospitalized Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Objective

This study aimed to evaluate the predictive value of neutrophil to lymphocyte ratio (NLR) for poor outcomes within 90-day in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

Methods

A retrospective study including 503 AECOPD patients was performed, and the subjects' clinical characteristics were collected. Binary logistic regression analysis was used to identify risk factors for 90-day poor outcomes in patients with AECOPD. Receiver-operating characteristic curves (ROC) and areas under the curves (AUC) were used to assess the ability of different biomarkers to predict the risk of 90-day mortality, readmission and re-exacerbation in patients with AECOPD.

Results

During the follow-up, 188 patients (38.4%) redeveloped exacerbations, 112 patients (22.9%) were readmitted, and 20 patients (4.1%) died directly resulted from COPD or COPD-related causes. Multivariate analysis demonstrated that age>72 years (OR: 14.817, 95% CI: 1.561-140.647), NLR>14.17 (OR: 9.611, 95% CI: 2.303-40.113), EOS<0.15% (OR: 8.621, 95% CI: 3.465-34.913) and BNP>2840ng/L (OR: 5.291, 95% CI: 1.367-20.474) at discharge were independent risk factors for 90-day mortality in AECOPD patients. NLR was the optimal biomarker for predicting 90-day mortality with an AUC of 0.802 (95% CI: 0.631-0.973). Using 14.17 as the critical value of NLR, the sensitivity was 76.7%, and the specificity was 88.9%. Compared with mortality, NLR had no significant advantage in predicting risk of short-term re-exacerbation (AUC=0.580, 95% CI:0.529-0.632, p=0.001) and readmission (AUC=0.555, 95% CI:0.497-0.614, p=0.045), with AUCs less than 0.6. In contrast, the predictive value of EOS (AUC=0.561, 95% CI:0.502-0.621, p=0.038) was slightly better than NLR in terms of readmission within 90 days. CRP did not serve as a well predictive biomarker for the risk of readmission and re-deterioration (p>0.05).

Conclusion

NLR is of great value in predicting the risk of poor outcomes, especially COPD associated mortality, in hospitalized patients with AECOPD within 90 days after discharge.

Association Between Neutrophil-Lymphocyte Ratio and All-Cause Mortality in Critically Ill Patients with Chronic Obstructive Pulmonary Disease: A Retrospective Cohort Study

BACKGROUND Neutrophil-lymphocyte ratio (NLR) is related to increased mortality risk in many diseases. However, there is limited research on critically ill patients with chronic obstructive pulmonary disease (COPD). A retrospective cohort study was performed to investigate whether NLR can be used as a biomarker to predict the mortality of critically ill COPD patients. MATERIAL AND METHODS In the research, the data were gathered from the database of the Medical Information Mart for Intensive Care-IV. The 28-day mortality was defined as the primary outcome, while the secondary outcomes were in-hospital and 90-day mortality. Through the application of the Kaplan-Meier curves and the multivariate Cox regression analysis, the potential association between NLR and mortality for critically ill patients with COPD was evaluated. For subgroup analysis, age, sex, ethnicity, mean blood pressure, and comorbidities were considered. RESULTS We extracted data on 2650 patients, of which 53.7% were male. A higher level of NLR was correlated with higher 28-day mortality risk. Compared to the lower quartile (NLR<4.56), HR (95% CI) of the upper quartile (NLR>16.86) was 1.75 (1.21-2.52) in the multivariate Cox regression model when adjusted for confounders (P=0.003). A similar tendency was found in the 90-day mortality (HR=1.59, 95% CI=1.16-2.19, P=0.004) and the in-hospital mortality (HR=1.71, 95% CI=1.22-2.42, P=0.002). Subgroup analyses showed that the correlation between NLR and 28-day mortality was stable. CONCLUSIONS The higher level of NLR is likely to be correlated with the increase of the all-cause mortality risk in critically ill patients with COPD, but this needs to be validated in future prospective research.

Prognostic value of lymphocyte count for in-hospital mortality in patients with severe AECOPD

Background

Patients with severe acute exacerbations of chronic obstructive pulmonary disease often have a poor prognosis. Biomarkers can help clinicians personalize the assessment of different patients and mitigate mortality. The present study sought to determine if the lymphocyte count could act as a risk factor for mortality in individuals with severe AECOPD.

Methods

A retrospective study was carried out with 458 cases who had severe AECOPD. For analysis, patients were divided into two groups on the basis of lymphocyte count: < 0.8 × 10⁹/L and ≥ 0.8 × 10⁹/L.

Results

Patients who fulfilled the criteria for inclusion were enrolled, namely 458 with a mean age of 78.2 ± 8.2 years. Of these patients, 175 had a low lymphocyte count. Compared to patients with normal lymphocyte counts, those with low counts were older (79.2 ± 7.4 vs. 77.5 ± 8.6 years, p = 0.036), had lower activities of daily living scores on admission (35.9 ± 27.6 vs. 47.5 ± 17.1, p < 0.001), and had a greater need for home oxygen therapy (84.6 vs. 72.1%, p = 0.002). Patients with low lymphocytes had higher mortality rates during hospitalization (17.1 vs. 7.1%, p = 0.001), longer hospital stay (median [IQR] 16 days [12–26] vs. 14 days [10–20], p = 0.002) and longer time on mechanical ventilation (median [IQR] 11.6 days [5.8–18.7] vs. 10.9 days [3.8–11.6], p < 0.001). The logistic regression analysis showed lymphocyte count < 0.8 × 10⁹/L was an independent risk factor associated with in-hospital mortality (OR 2.74, 95%CI 1.33–5.66, p = 0.006).

Conclusion

Lymphocyte count could act as a predictor of mortality in patients with severe AECOPD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02137-1.

Melatonin pretreatment modulates anti-inflammatory, antioxidant, YKL-40, and matrix metalloproteinases in endotoxemic rat lung tissue

We aimed to investigate the effects of melatonin administered before and during endotoxemia on the lung tissue of rats, cytokine, YKL-40, matrix metalloproteinase (MMP) and inhibitor levels, oxidative stress parameters, and energy balance. Sepsis was induced with lipopolysaccharide (LPS), the cell wall molecule of gram negative bacteria. Rats were divided into four groups, Control, LPS (Escherichia coli O127:B8, 20 mg/kg), melatonin (10 mg/kg), and melatonin+LPS (M+LPS). After injections, lung tissues samples were taken for experimental analyses. YKL-40, thiobarbituric acid reactive substances (TBARS), glutathione reductase (GR), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) enzymes levels were measured, high-energy components were analyzed; tumor necrosis factor-alpha (TNF-α), MMP-2, YKL-40, MMP-9, myeloperoxidase (MPO), tissue inhibitors of matrix metalloproteinase (TIMP)-1, and interleukin (IL)-10 immunoreactivities were investigated. In LPS group, YKL-40, creatine phosphate (both, p < 0.05), SOD, GR, adenosine mono-phophate (AMP), adenosine tri-phosphate (ATP) (for all, p < 0.01) were significantly decreased, while TBARS and adenosine di-phosphate (ADP) levels were increased (p < 0.01, p < 0.05; respectively) compared to other groups. MMP-2 and -9, TIMP-1, TNF-α, IL-10, and MPO immunoreactivity were investigated in LPS group. On the contrary, in M+LPS group, MMP-9, TIMP-1 immunoreactivities were not found and IL-10 and MMP-2 immunoreactivities were found with little involvement. In M+LPS group, YKL-40, GR, AMP, ATP, creatine phosphate (for all, p < 0.05), and SOD (p < 0.01) levels were significantly increased and TBARS levels were decreased (p < 0.05). In our study, we suggest that melatonin exerts a protective and curative effect by reducing the matrix metalloproteinase levels responsible for tissue damage balance, stimulating the release of antioxidant enzymes, regulating cytokines and energy balance during endotoxemia.

The utility of neutrophil-to-lymphocyte ratio determined at initial diagnosis in predicting disease stage and discriminating between active and stable disease in patients with sarcoidosis: cross-sectional study

OBJECTIVE

To evaluate the utility of neutrophil-lymphocyte ratio (NLR) determined at initial diagnosis in predicting advanced disease stage and discriminating between active and stable disease in sarcoidosis.

METHODS

A total of 465 patients with biopsy-proven sarcoidosis (age: 47 years, 70.5% females) were included in this retrospective cross-sectional study. Data on patient demographics, sarcoidosis stage, clinical status (stable and active), anti-inflammatory treatments, complete blood count, and inflammatory markers including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR) and platelet/mean platelet volume (MPV) ratio were recorded. NLR values were compared by subgrouping the patients according to the stage of sarcoidosis and clinical status, while the receiver operating characteristics (ROC) curve was plotted to determine the role of NLR in the identification of disease activity with the calculation of area under the curve (AUC) and cut-off value via ROC analysis.

RESULTS

Overall, active, and stable disease was evident in 36 (7.8%) and 427 (92.2%) patients, respectively. Median NLR values were significantly higher in patients with active disease compared with stable disease (3.31 (2.34-4.31) vs. 2.29 (1.67- 3.23), p=0.005). Advanced sarcoidosis stage was associated with significantly higher NLR values at stages 0, I, II, III and IV, respectively (p=0.001). ROC analysis revealed a NLR cut-off value of ≥2.39 (AUC (95% CI): 0.70(0.62 - 0.79), p<0.001) to discriminate between active and stable clinic with a sensitivity of 72.0% and specificity of 52.0%. The significantly higher percentage of patients with active vs. stable disease had NLR values ≥ 2.39 (74.0 vs. 47.0%, p=0.002).

CONCLUSION

Our findings indicate the potential utility of on-admission NLR values to predict the risk of advanced disease stage and to discriminate between active and stable disease in sarcoidosis. Measured via a simple, readily available, and low-cost test, NLR seems to be a valuable marker for monitoring disease activity and progression.

Are Neutrophil-Lymphocyte, Platelet-Lymphocyte, and Monocyte-Lymphocyte Ratios Prognostic Indicators in Patients With Chronic Obstructive Pulmonary Disease in Intensive Care Units?

Background and objective

Chronic obstructive pulmonary disease (COPD) is a condition in which the expiratory airflow is restricted and is characterized by inflammation. Recently, inflammation-related biomarkers such as neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and monocyte-lymphocyte ratio (MLR) have been used to predict the prognosis in COPD. The aim of this study was to evaluate the role of biomarkers such as NLR, PLR, and MLR in COPD patients in intensive care and to examine the ability of these markers to predict the prognosis [length of stay in hospital (LOSH), duration of mechanical ventilation (MV), length of stay in ICU (LOS ICU), and mortality].

Methods

A total of 562 patients who were treated in the ICU between 2018 and 2019 were retrospectively reviewed. Among them, 369 were patients with COPD. We evaluated clinical data including patient demographics, Charlson Comorbidity Index (CCI), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, Sequential Organ Failure Assessment (SOFA) score, LOS ICU, LOSH, duration of MV, as well as NLR, PLR, and MLR values. Data on patient deaths (30-day mortality) was obtained from the Death Notification System.

Results

Age, LOSH, CCI, and SOFA were found to predict mortality in COPD patients. In cases with mortality, age, inotropic use, MV duration, LOS ICU, APACHE II, CCI, SOFA, lymphocyte count, neutrophil count, platelet count, monocyte count, NLR, PLR, and MLR levels were statistically significantly higher than those in cases without mortality. There was a positive and low statistically significant relationship of NLR, PLR, and MLR with prognostic factors like MV duration, APACHE II scores, and SOFA scores.

Conclusion

The NLR, PLR, and MLR values may be used as prognostic indicators in COPD patients in intensive care. Although there are many studies endorsing the use of biomarkers such as NLR, PLR, and MLR as prognostic indicators, further comparative studies on this subject are still required to gain deeper insights into the topic.

Blood biomarkers associated with acute type II respiratory failure in COPD: A meta-analysis

OBJECTIVE

This study aims to summarize the risk factors of type II respiratory failure in patients with an acute exacerbation of chronic obstructive pulmonary disease (COPD), to guide clinical treatment in time, and consequently reduce the serious impact of COPD on human health.

METHODS

Five databases were searched for relevant articles on risk factors of acute exacerbation of COPD combinate with type II respiratory failure. We calculated the standard mean difference (SMD), odds ratio (OR), and their 95% confidence interval (95% CI) utilizing a fixed-effect model or a random-effect model according to the level of heterogeneity.

RESULTS

As of 14 May 2021, 13 articles were included in our meta-analysis. The results showed that low albumin and uric acid levels were the risk factors for type II respiratory failure in acute exacerbation of COPD patients, and the differences were statistically significant (albumin: SMD = -2.03, 95% CI: -2.81, -1.26; uric acid: SMD = -1.28, 95% CI: -1.41, -1.15). Besides, 10 other systematic markers have been reported to be the risk factors for type II respiratory failure of patients with acute exacerbation of COPD, but only in single study.

CONCLUSION

The meta-analysis results further confirm that low albumin and uric acid levels are risk factors for type II respiratory failure in acute exacerbation of COPD patients. Additionally, this analysis also summarizes many emerging inflammatory indicators, nutritional indicator, and cardiovascular system indicators to predict the progression of acute exacerbation of COPD to type II respiratory failure but only in single study.

Nine-Year Follow-Up of Interleukin 6 in Chronic Obstructive Pulmonary Disease - Complementary Results from Previous Studies

Background

Systemic manifestations of chronic obstructive pulmonary disease (COPD) are related to increased systemic inflammatory process; however, it is not entirely clear how much they are related and how the systemic inflammation, in particular interleukin-6 (IL-6), is associated with exacerbation and mortality risk.

Objective

To evaluate the role of IL-6 in COPD patients over nine years.

Study Design and Methods

A total of 133 COPD patients were assessed at baseline between 2004 and 2006 and reassessed after three and nine years through clinical evaluation, comorbidities, hematological blood count and IL-6 analysis.

Results

After nine years, 19 patients lost the follow-up and were not possible to identify the date of death of four patients; 12 refused to participate and 1 could not be involved due to recurrent exacerbations. Therefore, 33 patients were included in the reassessment after nine years of follow-up and 92 patients were included in the Cox mortality analysis with IL-6 as a time-dependent covariate. Regarding the inflammatory profile, in patients who survived after nine years, there was a significant increase in IL-6 [0.4 (0.2–0.8) vs 5.7 (3.4–11) pg/mL; p < 0.001] and reduction in lymphocyte count [2.1 (1.6–2.4) vs 1.4 (1.2–2.1)10^9/L; p < 0.01] with an increase in the neutrophil/lymphocyte ratio (2.0 ± 0.7 vs 2.7 ± 1.2; p = 0.003). The Cox mortality model did not show a statistical significance influence of IL-6 assessed during the follow-up.

Conclusion

There was a progressive increase in IL-6 during the follow-up, however, without influence on mortality.

Prognostic Value of Neutrophil:Lymphocyte and Platelet:Lymphocyte Ratios for 28-Day Mortality of Patients with AECOPD

Objective

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is the most common cause of hospitalization and death among COPD patients. Clinicians are seeking simple, inexpensive, and easily obtained biomarkers for prognostic evaluation. The aim of this study was to evaluate the association of the neutrophil:lymphocyte ratio (NLR), platelet:lymphocyte ratio (PLR) and lymphocyte:monocyte ratio (LMR) with 28-day mortality and assess the clinical prognostic utility of the NLR, PLR, and LMR in patients with AECOPD.

Methods

A retrospective study was conducted from January 2017 to April 2020 at Ningbo First Hospital. Clinical characteristics, NLR, PLR, LMR, serum levels of CRP, and other data were collected. Relationships between the NLR/PLR/LMR and CRP were evaluated with Pearson’s correlation test. Receiver-operating characteristic curves and area under the curve were used to assess the ability of NLR/PLR/LMR to predict 28-day mortality in patients with AECOPD. Optimal cutoff values were determined by the Youden index. Univariate and multivariate logistic regression analysis were used to identify risk factors for 28-day mortality in patients with AECOPD.

Results

By reviewing the medical case records, we collected 533 cases diagnosed with AECOPD for analysis. Death had occurred in 48 (9%) patients within 28 days. Univariate analysis identified age, smoking history, FEV₁% predicted, neutrophil count, lymphocyte count, NLR, PLR, CRP and blood-urea nitrogen as being associated with increased 28-day mortality. Multivariate analysis demonstrated that elevated NLR and PLR were significantly associated with death at 28 days. Receiver-operating characteristic analysis showed that the NLR had the highest area under the curve (0.801), with optimal cutoff of 6.74, sensitivity of 82.54%, and specificity of 71.38%. At a cutoff of 203.6, the corresponding sensitivity, specificity, and area under the curve of the PLR were 76.86%, 65.27%, and 0.75. The LMR failed to show prognostic significance.

Conclusion

Our results indicated that the NLR and PLR were associated with 28-day mortality in patients with AECOPD. These ratios may serve as prognostic biomarkers for short-term mortality in patients hospitalized with AECOPD.

The predictive value of neutrophil-to-lymphocyte ratio for chronic obstructive pulmonary disease: a systematic review and meta-analysis

INTRODUCTION

There was inconsistent results regarding the associations of neutrophil to lymphocyte ratio (NLR) with the progression and prognosis of chronic obstructive pulmonary disease (COPD).

AREAS COVERED

This paper assess the role of NLR on the progression and prognosis of COPD using a meta-analytic approach. PubMed, EmBase, and the Cochrane library were systematically searched. The pooled weighted mean differences and odds ratios with 95% confidence intervals were applied for continuous and categorical variables using the random-effects model.

EXPECT COMMENATRY

NLR was significantly high when comparing COPD patients to healthy individuals, and acute exacerbation COPD to stable COPD. Moreover, elevated NLR were significantly associated with higher risk of mortality and exacerbation.

Neutrophil-to-Lymphocyte Ratio Predicts Clinical Outcome of Severe Acute Exacerbation of COPD in Frequent Exacerbators

Purpose

Frequent exacerbators are a specific phenotype of chronic obstructive pulmonary disease (COPD), whose clinical characteristics and prognostic biomarkers during severe acute exacerbation (AECOPD) have not yet been fully elucidated. The aim of this study was to investigate the clinical features of severe AECOPD in frequent exacerbators and explore the predictive value of the neutrophil-to-lymphocyte ratio (NLR) for outcome in this phenotype during severe exacerbation.

Patients and Methods

A total of 604 patients with severe AECOPD were retrospectively included in the study. Subjects were defined as frequent exacerbators if they experienced two or more exacerbations in the past year. Clinical characteristics and worse outcome (ICU admission, or invasive ventilation, or in-hospital mortality) during severe AECOPD were compared between frequent exacerbators and non-frequent ones. Furthermore, the relationship between NLR and worse outcome in frequent exacerbators was analyzed using logistic regression and receiver operating characteristic (ROC).

Results

Among 604 patients with severe AECOPD, 282 (46.69%) were frequent exacerbators and 322 (53.31%) were non-frequent exacerbators. Compared with the non-frequent ones, frequent exacerbators presented higher levels of NLR (5.93 [IQR, 3.40–9.28] vs 4.41 [IQR, 2.74–6.80]; p<0.001), and more worse outcome incidence (58 [20.57%] vs 38 [11.80%]; p=0.003). Moreover, among the frequent exacerbators, NLR levels in the patients with worse outcome were much higher than in those without worse outcome (11.09 [IQR, 7.74–16.49] vs 5.28 [IQR, 2.93–7.93]; p<0.001). Increased NLR was significantly associated with a higher risk of worse outcome in frequent exacerbators (OR, 1.43; 95% CI, 1.28–1.64; p<0.001). Furthermore, ROC analysis revealed that a cut-off value of 10.23, NLR could predict worse outcome of severe AECOPD in frequent exacerbators (sensitivity 62.1%, specificity 92.0%, AUC 0.833).

Conclusion

Frequent exacerbators exhibited an increased level of NLR and a higher proportion of worse outcome during severe AECOPD. NLR is expected to be a promising predictive biomarker for the prognosis of severe AECOPD in frequent exacerbators.

Calprotectin in Lung Diseases

Calprotectin (CLP) is a heterodimer formed by two S-100 calcium-binding cytosolic proteins, S100A8 and S100A9. It is a multifunctional protein expressed mainly by neutrophils and released extracellularly by activated or damaged cells mediating a broad range of physiological and pathological responses. It has been more than 20 years since the implication of S100A8/A9 in the inflammatory process was shown; however, the evaluation of its role in the pathogenesis of respiratory diseases or its usefulness as a biomarker for the appropriate diagnosis and prognosis of lung diseases have only gained attention in recent years. This review aimed to provide current knowledge regarding the potential role of CLP in the pathophysiology of lung diseases and describe how this knowledge is, up until now, translated into daily clinical practice. CLP is involved in numerous cellular processes in lung health and disease. In addition to its anti-microbial functions, CLP also serves as a molecule with pro- and anti-tumor properties related to cell survival and growth, angiogenesis, DNA damage response, and the remodeling of the extracellular matrix. The findings of this review potentially introduce CLP in daily clinical practice within the spectrum of respiratory diseases.

Serum calprotectin as new biomarker for disease severity in idiopathic pulmonary fibrosis: a cross-sectional study in two independent cohorts

BACKGROUND

Non-invasive biomarkers for the assessment of disease severity in idiopathic pulmonary fibrosis (IPF) are urgently needed. Calprotectin belongs to the S-100 proteins produced by neutrophils, which likely contribute to IPF pathogenesis. Calprotectin is a well-established biomarker in inflammatory bowel diseases. In this cross-sectional study, we aimed to establish the potential role of calprotectin as a biomarker in IPF. Specifically, we hypothesised that patients with IPF have higher serum calprotectin levels compared with healthy controls, and that calprotectin levels are associated with disease severity.

METHODS

Blood samples were obtained from healthy volunteers (n=26) and from two independent IPF cohorts (derivation cohort n=26, validation cohort n=66). Serum calprotectin levels were measured with a commercial kit adapted for that purpose and compared between healthy controls and patients with IPF. Clinical parameters, including forced vital capacity, diffusing capacity for carbon monoxide (DLCO) and the Composite Physiologic Index (CPI), were correlated with calprotectin serum levels.

RESULTS

The IPF derivation cohort showed increased serum calprotectin levels compared with healthy controls (2.47±1.67 vs 0.97±0.53 µg/mL, p<0.001). In addition, serum calprotectin levels correlated with DLCO% predicted (r=-0.53, p=0.007) and with CPI (r=0.66, p=0.007). These findings were confirmed in an independent IPF validation cohort.

CONCLUSION

Serum calprotectin levels are significantly increased in patients with IPF compared with healthy controls and correlate with DLCO and CPI. Calprotectin might be a potential new biomarker for disease severity in IPF.

Plasma calprotectin as a biomarker of mortality at antiretroviral treatment initiation in advanced HIV - pilot study

Background: In advanced HIV, significant mortality occurs soon after starting antiretroviral treatment (ART) in low- and middle-incomes countries. Calprotectin is a biomarker of innate response to infection and inflammatory conditions. We examined the association between plasma calprotectin collected before ART treatment and mortality among individuals with advanced HIV.   Methods: We conducted a pilot case-cohort study among HIV infected adults and adolescents over 13 years old with CD4+ <100/mm3 at ART initiation at two Kenyan sites. Participants received three factorial randomised interventions in addition to ART within the REALITY trial (ISRCTN43622374). Calprotectin collected at baseline (before ART) and after 4 weeks of treatment was measured in archived plasma of those who died within 24 weeks (cases) and randomly selected participants who survived (non-cases). Association with mortality was assessed using Cox proportional hazards models with inverse sampling probability weights and adjusted for age, sex, site, BMI, viral load, randomised treatments, and clustered by CD4+ count (0-24, 25-49, and 50-99 cells/mm3).   Results: Baseline median (IQR) plasma calprotectin was 6.82 (2.65-12.5) µg/ml in cases (n=39) and 5.01 (1.92-11.5) µg/ml in non-cases (n=58). Baseline calprotectin was associated with age, neutrophil count and the presence of cough, but not other measured indicators of infection. In adjusted multivariable models, baseline calprotectin was associated with subsequent mortality: HR 1.64 (95% CI 1.11 - 2.42) and HR 2.77 (95% CI 1.58 - 4.88) for deaths during the first twenty-four and four weeks respectively. Calprotectin levels fell between baseline and 4 weeks among both cases and non-cases irrespective of randomised interventions.   Conclusions: Among individuals with advanced HIV starting ART in Kenya, plasma calprotectin may have potential as a biomarker of early mortality. Validation in larger studies, comparison with other biomarkers and investigation of the sources of infection and inflammation are warranted.

Systemic Inflammatory Markers Predict Detrimental Outcome of Urosepsis in Kidney Transplant Recipients

BACKGROUND

Urosepsis is a frequent cause of hospitalization among kidney transplant recipients (KTxR). Systemic inflammatory markers may reflect disease severity; nevertheless, their predictive value has not been evaluated in KTxRs.

AIMS

We sought to investigate the diagnostic and prognostic value of blood-derived systemic inflammatory markers during urosepsis in KTxR.

METHODS

We retrospectively enrolled 80 transplant recipients who were hospitalized between 2014 and 2017 due to urosepsis and followed for at least 1 year. Multiple parameters were calculated from medical records. The study endpoint was defined as death, graft loss, or a more than double serum creatinine level compared with baseline.

RESULTS

Seventeen patients reached an endpoint and presented at admission significantly lower total serum protein [g/dL] (5.0 ± 0.6 vs 6.0 ± 0.7) and higher urea [mg/dL] (161, 118-218 vs 80, 56-125), neutrophil-to-lymphocyte ratio (NLR) (20.0, 12.5-48.3 vs 12.9, 7.0-20.1), platelet-to-lymphocyte ratio (PLR) (447, 203-706 vs 231, 160-357), derived neutrophil-to-lymphocyte ratio (dNLR) (8.5, 5.6-10.4 vs 5.3, 2.9-8.5), and maximal Sequential Organ Failure Assessment (SOFA) score (6, 4-7 vs 3, 3-5). Among blood markers, NLR showed the strongest correlation with C-reactive protein, procalcitonin, creatinine, urea, and maximal SOFA score. The NLR cut-off value >15 predicted endpoint occurrence with 59% specificity and 75% sensitivity (area under the curve [AUC] 0.67, P = .038). The combined impact of NLR, urea, and total serum protein increased the prognostic precision (sensitivity 85% and specificity 84%, AUC = 0.88, P < .001).

CONCLUSIONS

The combined impact of NLR, urea, and total serum protein identifies KTxR who are at risk of a bad outcome after urosepsis and require more meticulous care.

Neutrophil to lymphocyte ratio as prognostic and predictive factor in patients with coronavirus disease 2019: A retrospective cross-sectional study

This retrospective study was designed to explore whether neutrophil to lymphocyte ratio (NLR) is a prognostic factor in patients with coronavirus disease 2019 (COVID‐19). A cohort of patients with COVID‐19 admitted to the Tongren Hospital of Wuhan University from 11 January 2020 to 3 March 2020 was retrospectively analyzed. Patients with hematologic malignancy were excluded. The NLR was calculated by dividing the neutrophil count by the lymphocyte count. NLR values were measured at the time of admission. The primary outcome was all‐cause in‐hospital mortality. A multivariate logistic analysis was performed. A total of 1004 patients with COVID‐19 were included in this study. The mortality rate was 4.0% (40 cases). The median age of nonsurvivors (68 years) was significantly older than survivors (62 years). Male sex was more predominant in nonsurvival group (27; 67.5%) than in the survival group (466; 48.3%). NLR value of nonsurvival group (median: 49.06; interquartile range [IQR]: 25.71‐69.70) was higher than that of survival group (median: 4.11; IQR: 2.44‐8.12; P < .001). In multivariate logistic regression analysis, after adjusting for confounding factors, NLR  more than 11.75 was significantly correlated with all‐cause in‐hospital mortality (odds ratio = 44.351; 95% confidence interval = 4.627‐425.088). These results suggest that the NLR at hospital admission is associated with in‐hospital mortality among patients with COVID‐19. Therefore, the NLR appears to be a significant prognostic biomarker of outcomes in critically ill patients with COVID‐19. However, further investigation is needed to validate this relationship with data collected prospectively.

NLR is a significant prognostic biomarker of outcomes in critically ill patients with COVID‐19.

COVID‐19 is more likely to infected those elder men with chronic comorbidities.

NLR may also help in the early identification of older patients at higher risk of COVID‐19.

Close monitoring and timely intervention are needed for elderly patients with COVID‐19.

Plasma calprotectin as a biomarker of mortality at antiretroviral treatment initiation in advanced HIV - pilot study

Background: In advanced HIV, significant mortality occurs soon after starting antiretroviral treatment (ART) in low- and middle-incomes countries. Calprotectin is a biomarker of innate response to infection and inflammatory conditions. We examined the association between plasma calprotectin at initiation of ART and mortality among individuals with advanced HIV. Methods: We conducted a pilot case-cohort study among HIV infected adults and children over 5 years old with CD4 + <100/mm 3 at ART initiation at two Kenyan sites. Participants received three factorial randomised interventions in addition to ART within the REALITY trial ( ISRCTN43622374). Calprotectin was measured by ELISA in archived plasma of those who died within 24 weeks (cases) and randomly selected participants who survived for 48 weeks (non-cases) for whom samples were available. Factors associated with baseline plasma calprotectin were investigated using linear regression. To test association with mortality, Cox proportional hazards models with inverse sampling probability weights and adjusted for age, sex, site, BMI, viral load, randomised treatments, and clustered by CD4 count were fitted. Results: Baseline median (IQR) plasma calprotectin was 6.82 (2.65-12.5) µg/ml in cases (n=39) and 5.01 (1.92-11.5) µg/ml in non-cases (n=58). Baseline calprotectin was associated with age, neutrophil count and the presence of cough, but not other measured indicators of infection. In adjusted multivariable models, baseline calprotectin was associated with subsequent mortality: HR 1.64 (95% CI 1.11 - 2.42) and HR 2.77 (95% CI 1.58 - 4.88) for deaths during the first twenty-four and four weeks respectively. Calprotectin levels fell between baseline and 4 weeks among both cases and non-cases irrespective of randomised interventions. Conclusion: Among individuals with advanced HIV starting ART in Kenya, plasma calprotectin may have potential as a biomarker of early mortality. Validation in larger studies, comparison with other biomarkers and investigation of the sources of infection and inflammation are warranted.

The Association Between the Neutrophil-to-Lymphocyte Ratio and Mortality in Patients With Acute Respiratory Distress Syndrome: A Retrospective Cohort Study

PURPOSE

Systemic inflammation relates to the initiation and progression of acute respiratory distress syndrome (ARDS). As neutrophil-to-lymphocyte ratio (NLR) has been shown to be a prognostic inflammatory biomarker in various diseases, in this study, we sought to explore whether NLR is a prognostic factor in patients with ARDS.

METHODS

A retrospective study was performed on patients diagnosed as ARDS admitted to the intensive care unit (ICU). We calculated the NLR by dividing the neutrophil count by the lymphocyte count and categorized patients into four groups based on quartile of NLR values. The association of NLR quartiles and 28-day mortality was assessed using multivariable Cox regression. Secondary outcomes included ICU mortality and hospital mortality.

RESULTS

A total of 224 patients were included in the final analysis. The median (interquartile range) NLRs from first quartile to fourth quartile were as follows: 6.88 (4.61-7.94), 13.06 (11.35-14.89), 20.99 (19.09-23.19), and 39.39 (32.63-50.15), respectively. The 28-day mortalities for the same groups were as follows: 10.7%, 19.6%, 41.4%, and 53.6% (P < 0.001). Cox regression analysis showed NLR was a significant risk factor predicting 28-day mortality (first quartile, reference group; second quartile, adjusted hazard ratio [HR]= 1.674, 95% confidence interval [CI], 0.462-6.063, P = 0.432; third quartile, HR = 5.075, 95% CI, 1.554-16.576, P = 0.007; fourth quartile, HR = 5.815, 95% CI, 1.824-18.533, P = 0.003). Similar trends were observed for ICU mortality and hospital mortality.

CONCLUSIONS

High NLR was associated with the poor outcome in critically ill patients with ARDS. The NLR therefore seems to be a prognostic biomarker of outcomes in critically ill patients with ARDS. Further investigation is required to validate this relationship with data collected prospectively.

The prognostic values of neutrophil to lymphocyte ratio for outcomes in chronic obstructive pulmonary disease

OBJECTIVE

Neutrophil to lymphocyte ratio (NLR) is considered as an inflammatory biomarker for clinical outcomes in patients with chronic obstructive pulmonary disease (COPD). We aimed to conduct a meta-analysis to evaluate the prognostic values of NLR for the exacerbation and mortality in patients with COPD.

METHODS

We searched the database of Cochrane Central Register of Controlled Trials, EMBASE, and PubMed, before September 2017. The eligible studies were retrieved by 2 authors independently following the criteria. The pooled odds ratios (ORs) of included studies were used to evaluate the prognostic values of NLR. Subgroup analyses were conducted to make the results more accurate.

RESULTS

Nine studies with 5140 patients were enrolled in this analysis. The high NLR was associated with higher risk of exacerbation (OR: 3.81, 95% confidence interval [CI]: 1.20-12.13, P = .02) and mortality (OR: 2.60, 95% CI: 1.48-4.57, P < .01). By subgroup analysis, high NLR could predict the mortality in patients >70 years (OR: 2.16, 95% CI: 1.17-3.98, P = .01) but not in patients <70 years (OR: 4.08, 95% CI: 0.91-18.24, P = .07), and had a higher predictive ability in Asian group (OR: 3.64, 95% CI: 1.87-7.08, P < .01) than Eurasia group (OR: 1.82, 95% CI: 1.43-2.32, P < .01). In addition, high NLR could predict the short-term mortality (OR: 2.70, 95% CI: 1.10-6.63, P = .03) and the long-term mortality (OR: 2.61, 95% CI: 1.20-5.65, P = .02).

CONCLUSIONS

The NLR may be an independent predictor for incidence of exacerbation in patients with COPD. In addition, high NLR may be associated with higher mortality in patients with COPD, especially for Asian and the patients with higher mean NLR.

Serum Biomarkers in Patients with Stable and Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Comparative Study

Background

Mean platelet volume (MPV), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have all been investigated as novel inflammatory markers of cardiac and oncological diseases, while there is only a limited number of studies investigating these markers in chronic obstructive pulmonary disease (COPD). In the present study we examine NLR, PLR; and other markers, such as eosinophil, MPV, plateletcrit (PCT), platelet distribution width (PDW), red cell distribution width (RDW), and C-reactive protein (CRP) in patients with stable and acute exacerbation of COPD.

Methods

Stable COPD (Group 1, n=140), COPD with acute exacerbation (Group 2, n=110), and healthy controls (Group 3, n=50) were included in the study. Leukocyte, CRP, hemoglobin (HB), RDW, platelet, MPV, PCT, PDW, neutrophil, lymphocyte, eosinophil, NLR, and PLR were analyzed in all groups.

Results

HB, leukocyte, platelet, neutrophil, eosinophil, MPV, PCT, CRP, NLR, and PLR were significantly higher, while the lymphocyte was lower in Group 1 than in Group 3. Leukocyte, neutrophil, RDW, CRP, NLR, and PLR were significantly higher, while lymphocyte was lower in Group 2 than in Group 3. Leukocyte, neutrophil, RDW, CRP, NLR, and PLR were significantly higher, while HB, platelet, MPV, PCT, and lymphocyte were significantly lower in Group 2 than in Group 1. NLR and PLR increased significantly in patients with bronchiectasis when compared to those without in Group 1.

Conclusions

Our study results suggest that NLR, PLR and RDW can be used as simple and cost-effective markers for the evaluation of severity of exacerbation and for predicting hospitalization and further exacerbations in patients with COPD.

Defining the role of neutrophil-to-lymphocyte ratio in COPD: a systematic literature review

COPD is characterized by a pulmonary and systemic inflammatory process. Several authors have reported the elevation of multiple inflammatory markers in patients with COPD; however, their use in routine clinical practice has limitations. The neutrophil-to-lymphocyte ratio (NLR) is a useful and cost-effective inflammatory marker derived from routine complete blood count. We performed a systematic literature review using the PRISMA statement. Twenty-two articles were included, recruiting 7,601 COPD patients and 784 healthy controls. Compared with controls, COPD patients had significantly higher NLR values. We found a significant correlation between the NLR and clinical/functional parameters (FEV₁, mMRC, and BODE index) in COPD patients. Elevation of the NLR is associated with the diagnosis of acute exacerbation of COPD (pooled data propose a cut-off value of 3.34 with a median sensitivity, specificity, and area under the curve of 80%, 86%, and 0.86, respectively). Additionally, increased NLR is also associated with the diagnosis of a bacterial infection in exacerbated patients, with a cut-off value of 7.30, although with a low sensitivity and specificity. The NLR is an independent predictor of in-hospital and late mortality after exacerbation. In conclusion, the NLR could be a useful marker in COPD patients; however, further studies are needed to better identify the clinical value of the NLR.

Predictive value of neutrophil to lymphocyte ratio in patients with acute exacerbation of chronic obstructive pulmonary disease

OBJECTIVE

This study aimed to determine the predictive value of the neutrophil to lymphocyte ratio (NLR) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

METHODS

A retrospective study was conducted from March 2012 to May 2016 in Fuxing Hospital, Capital University of Medical Science. We collected 906 cases (525 males, 381 females, mean age 81.86±9.75 years) diagnosed with AECOPD. The NLR was calculated from their white blood cell (WBC), neutrophil (NEU), and lymphocyte (LYM) counts, which were obtained at laboratory examination.

RESULT

After treatment, 698 patients with AECOPD improved. The NLR was higher at admission (6.89±6.82) than after treatment (4.19±5.11) (P = 0.000). The area under the receiver operating characteristic curve (AUC) of the NLR for predicting the 28-day mortality rate was 0.737. Using 8.130 as the critical NLR value, the sensitivity was 60.5%, and the specificity was 74.8%. The AUC of the NLR for predicting the frequency of the need for invasive mechanical ventilation was 0.732. Using 10.345 as the critical NLR value, the sensitivity was 54.3%, and the specificity was 84.8%. The AUC of WBC, NEU and LYM for predicting 28-day mortality and the need for invasive mechanical ventilation in these patients were all less than 0.7. An increased NLR was an independent risk factor for 28-day mortality (OR = 1.067, 95% CI = 1.039 to 1.095, P = 0.000), intensive care unit occupancy (OR = 1.046, 95% CI = 1.023 to 1.068, P = 0.000), and the need for invasive mechanical ventilation (OR = 1.042, 95% CI = 1.019 to 1.066, P = 0.000). Compared with those patients without comorbidities, patients with renal dysfunction or upper gastrointestinal bleeding had an increased risk of death within 28 days (OR = 3.102, 95% CI = 1.525 to 6.312; OR = 4.598, 95% CI = 1.825 to 11.583, respectively), ICU admission (OR = 2.228, 95% CI = 1.286 to 3.860; OR = 3.103, 95% CI = 1.402 to 6.866, respectively), and the need for invasive mechanical ventilation (OR = 3.572, 95% CI = 1.822 to 7.000; OR = 4.279, 95% CI = 1.823 to 10.045, respectively).

CONCLUSION

In patients with AECOPD, the accuracy of the NLR for predicting the 28-day mortality rate and frequency of the need for mechanical ventilation was significantly higher than the accuracy of WBC, NEU and LYM counts. AECOPD patients with an NLR≥8.130 had higher 28-day mortality rate, while those with an NLR ≥10.345 were more likely to need invasive mechanical ventilation.

Neutrophil/lymphocyte ratio is helpful for predicting weaning failure: a prospective, observational cohort study

Background

To assess the usefulness of the neutrophil/lymphocyte ratio (NLR), a marker of inflammation and/or stress, for predicting weaning failure in patients receiving invasive mechanical ventilation (IMV), compared to levels of leukocytes and C-reactive protein (CRP).

Methods

This observational prospective cohort study was conducted from July 2013 to December 2016 in an intensive care unit in China, enrolling 269 consecutive patients receiving IMV. Patients underwent a spontaneous breathing trial (SBT) if they were ready to wean, and underwent extubation if they passed the SBT. The evaluated markers were measured immediately prior to SBT, and compared between weaning-failure and weaning-success patients. Receiver-operating characteristic (ROC) curve and logistic regression analyses were used to evaluate the ability of these markers to predict weaning failure.

Results

In all, 94 (34.9%) patients failed the weaning process (66 failed SBT and 28 presented with post-extubation respiratory distress). NLR was a better predictor of failure (area under the ROC curve, 0.69; 95% CI, 0.62-0.76) than leukocyte levels (0.60, 0.53-0.67) and CRP values (0.58, 0.51-0.65). NLR >11, leukocyte counts >10.5×10⁹/L, and CRP >58 mg/L prior to weaning had the best combination of sensitivity (73%, 64%, and 63%, respectively), specificity (59%, 55%, and 63%), positive predictive value (49%, 43%, and 48%), negative predictive value (81%, 74%, and 76%), and diagnostic accuracy (64%, 58%, and 63%) for predicting weaning failure. However, only NLR >11 (odds ratio, 5.91; 95% CI, 3.08-11.33; P<0.001) was an independent predictor of weaning failure in the adjusted logistic regression model.

Conclusions

NLR may be a useful marker for predicting weaning failure, and weaning at NLR >11 might be considered with caution. Further study with a larger sample size and with weaning outcome as a variable of concern is warranted. Trial registration: ClinicalTrials.gov identifier: NCT02981589.

The neutrophil-to-lymphocyte ratio as a marker of chronic obstructive pulmonary disease and its exacerbations: A systematic review and meta-analysis

INTRODUCTION

The main white blood cell populations, neutrophils and lymphocytes, are involved in the pathophysiology of chronic obstructive pulmonary disease (COPD). We conducted a systematic review and meta-analysis of studies investigating the relationship between the neutrophil to lymphocyte ratio (NLR, a marker of subclinical inflammation), presence of COPD, and its exacerbations.

METHODS

A comprehensive literature search was conducted in Pubmed, Web of Science and Scopus databases; two investigators independently reviewed suitable studies.

RESULTS

Nine studies, from 247 initially identified, were included in the meta-analysis. Seven studies, in 775 COPD patients with stable disease and 496 healthy controls, showed a significant increase in NLR values in stable COPD (standardised mean difference, SMD, 0.773, 95% CI 0.410-1.136; P < 0.001). Furthermore, in six studies in 527 COPD patients with acute exacerbation and 620 COPD patients with stable disease, NLR values were significantly higher in patients with exacerbations (random effects SMD 0.850, 95% CI 0.549-1.151; P < 0.001).

CONCLUSIONS

Our meta-analysis showed that NLR values are significantly higher in stable COPD patients when compared to healthy individuals, although the magnitude of the difference is reduced after trim and fill adjustment, and in patients with COPD exacerbations when compared to patients with stable disease. Further studies, in larger cohorts, are needed to confirm whether the NLR is a useful tool in discriminating between COPD patients with stable disease, those with acute exacerbations, and subjects without the disease.

Prognostic value of the absolute lymphocyte count in patients admitted for acute heart failure

BACKGROUND

Low relative lymphocyte count is an important prognostic marker in acute heart failure (AHF); however, it could be influenced by other abnormalities in white cells count. Our purpose is to evaluate if low absolute lymphocyte count (ALC) is an independent predictor of events in patients with AHF.

METHODS

In a retrospective analysis, we included 309 patients with AHF, divided into two groups according to the median value of ALC at admission (1410 cells/μl). The primary end point was all-cause mortality or urgent heart transplantation within 1 year.

RESULTS

Patients with low ALC were older and had more comorbidity, namely atrial fibrillation, chronic kidney disease, chronic obstructive pulmonary disease and anemia. Low ALC was associated with higher all-cause mortality or urgent heart transplantation at 1 year (24.3 vs 13.0%; P = 0.012). In a multivariable model, the independent predictors of mortality at 1 year were ALC 1410 cells/μl or less at admission [hazard ratio 2.04; CI (confidence interval) 95% (1.06-3.95); P = 0.033], age [hazard ratio 1.08; CI 95% (1.04-1.12); P < 0.001], baseline serum creatinine [hazard ratio 1.25; CI 95% (1.05-1.50); P = 0.012] and baseline serum Na [hazard ratio 0.91; CI 95% (0.85-0.98); P = 0.013].

CONCLUSION

Low ALC in patients with AHF is associated with higher in-hospital mortality during the hospitalization and is an independent predictor of long-term mortality.

Clinical utility of blood neutrophil-lymphocyte ratio in Japanese COPD patients

Background

Neutrophil-to-lymphocyte ratio (NLR) is a biomarker of inflammation in chronic obstructive pulmonary disease (COPD) patients. But, a meaningful threshold and the longitudinal changes are unknown. We aimed to investigate the association between NLR and the clinical characteristics of COPD patients and to determine a meaningful threshold and the longitudinal changes for NLR.

Methods

Keio University and its affiliate hospitals conducted an observational COPD cohort study over 3 years. We performed a blood examination and a pulmonary function test. Blood examination was completed at baseline and annually thereafter, at a time when the disease was stable. Two hundred seventy-four patients who had at least 3 blood examinations over 3 years were included.

Results

Baseline NLR was correlated with baseline C-reactive protein (CRP) (r = 0.18, p = 0.003) and SAA (r = 0.34, p <  0.001). We defined an NLR score of 2.7 as the arbitrary cut-off value based on upper quartile points. COPD patients with NLR ≥ 2.7 were older (p = 0.037), had a lower BMI (p = 0.005) and a lower %FEV1 (p = 0.0003) compared to patients with NLR < 2.7. Receiver-operating-characteristic (ROC) curves showed the optimal cutoff for the baseline NLR in the predicting moderate/severe exacerbation to be 2.7, which was same as the upper quartile points. Follow-up analysis over 3 years revealed that the differences in the trends of NLR among the three groups based on the categories of exacerbations (moderate or severe, mild, no exacerbation) were significant (p = 0.006).

Conclusions

NLR is associated with COPD severity and exacerbations. For predicting exacerbations, we estimated the threshold of NLR to be 2.7 at baseline.

Trial registration

Clinical trial registered with the University Hospital Medication Information Network (UMIN000003470, April 10, 2010).

Electronic supplementary material

The online version of this article (10.1186/s12890-018-0639-z) contains supplementary material, which is available to authorized users.

Neutrophil to lymphocyte ratio and clinical outcomes in COPD: recent evidence and future perspectives

Chronic obstructive pulmonary disease (COPD) is a disabling condition that is characterised by poorly reversible airflow limitation and inflammation. Acute exacerbations of COPD are a common cause of hospitalisation and death among COPD patients. Several biochemical markers have been studied as outcome predictors in COPD; however, their measurement often requires significant time and resources. Relatively simple biomarkers of inflammation calculated from routine complete blood count tests, such as the neutrophil to lymphocyte ratio (NLR), might also predict COPD progression and outcomes. This review discusses the available evidence from studies investigating the associations between the NLR, COPD exacerbations and death in this patient group.

Blood biomarkers as predictors of long-term mortality in COPD

BACKGROUND

Blood biomarkers are easily accessible and might reflect chronic obstructive pulmonary disease (COPD) activity.

AIM

The aim of this study was to determine whether a panel of blood biomarkers [C-reactive protein (CRP), neutrophils, eosinophils, albumin and vitamin D] could predict mortality in COPD.

METHODS

We analyzed data from 431 COPD participants to the 2007-2010 National Health and Nutrition Examination Surveys who were followed for a median time of 36 months. COPD was defined as post-bronchodilator forced expiratory volume in 1 second (FEV1) and forced vital capacity ratio <0.70. Weibull survival analysis adjusted for covariates was performed to calculate the risk of mortality associated with the biomarkers, and C-statistics was used to assess their added predictive value.

RESULTS

During follow-up, 38 of the 431 participants died. Participants with high CRP, eosinophil count <2%, hypoalbuminemia and hypovitaminosis D had worse baseline FEV1 and subsequently higher mortality compared to controls. In adjusted analysis, increasing CRP [hazard ratio (HR): 4.45, 95% CI: 1.91-10.37] and neutrophil count (HR: 1.07, 95% CI: 1.03-1.11) as well as decreasing eosinophil count (HR: 7.03, 95% CI: 2.05-24.01) were associated with an increased risk of mortality. The addition of CRP with eosinophil and/or neutrophil count significantly improved a base model for the prediction of mortality which included age, gender, race/ethnicity, body mass index, smoking, poverty income ratio, asthma, diabetes, hypertension and history of stroke or myocardial infarction.

CONCLUSION

High CRP and neutrophils as well as low eosinophils are predictive of poor COPD prognosis. They also add significant value to prediction models of mortality in COPD.

Prognostic role of neutrophil-lymphocyte ratio and platelet-lymphocyte ratio for hospital mortality in patients with AECOPD

Background and objectives

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is one of the leading causes of hospitalization and is associated with considerable mortality, for which clinicians are seeking useful and easily obtained biomarkers for prognostic evaluation. This study aimed to determine the potential role of the neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) as prognostic makers for hospital mortality in patients with AECOPD.

Methods

We included 303 patients with AECOPD in this retrospective study. Clinical characteristics, NLR, PLR, and serum levels of C-reactive protein (CRP) and other data were collected. Relationships between NLR/PLR and CRP were evaluated by Pearson’s correlation test. Receiver operating characteristics curve and the area under the curve (AUC) were used to assess the ability of NLR and PLR to predict hospital mortality in patients with AECOPD.

Results

Mean levels of NLR and PLR of all patients with AECOPD were 7.92±8.79 and 207.21±148.47, respectively. NLR levels correlated with serum CRP levels (r=0.281, P<0.05). The overall hospital mortality rate was 12.21% (37/303). Levels of NLR and PLR were signifi-cantly higher among non-survivors compared to survivors of AECOPD (both P<0.05). At a cut-off value of 6.24, the sensitivity and specificity of the NLR in predicting hospital mortality were 81.08% and 69.17%, respectively, with an AUC of 0.803. At a cut-off of 182.68, the corresponding sensitivity, specificity and AUC of PLR were 64.86%, 58.27%, and 0.639. The combination of NLR, PLR, and CRP increased the prognostic sensitivity.

Conclusion

NLR and PLR levels were increased in non-survivor patients with AECOPD, and the NLR may be simple and useful prognostic marker for hospital mortality in patients with AECOPD. More studies should be carried out to confirm our findings.

Evaluation of platelet lymphocyte ratio and 90-day mortality in patients with acute exacerbation of chronic obstructive pulmonary disease

BACKGROUND

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) have high mortality and health care costs. The platelet to lymphocyte ratio (PLR) is a marker of inflammation and has been reported to be elevated in patients with AECOPD compared to stable state. In this study, we sought to evaluate the association of the PLR in patients with AECOPD with 90-day mortality.

METHODS

We conducted a retrospective cohort study of patients admitted to our institution with a primary diagnosis of AECOPD between January 2014 and July 2014. Blood test results on admission were recorded. The primary outcomes were 90-day mortality.

RESULTS

One hundred and eighty-one AECOPD patients were considered for the study. Death had occurred in 16 (9%) patients within 90 days of hospital discharge. Univariable analysis identified age, haemoglobin, neutrophil count, and urea level, neutrophil lymphocyte ratio (NLR) and PLR as being associated with increased 90-day mortality. Multivariable logistic regression analysis variables demonstrated that only PLR (P=0.03) was significantly associated with death at 90 days. Receiver operator characteristic analysis identified PLR ≥235 had a sensitivity of 63% and specificity of 74% in predicting 90-day mortality. PLR was ≥235 was also associated with worse survival (days) [mean ± standard deviation (SD): PLR ≥235 vs. PLR <235: 512±358 vs. 626±346, P=0.004].

CONCLUSIONS

A PLR ≥235 was significantly associated with 90-day mortality, which may provide prognostic guidance to clinicians.

Role of neutrophil to lymphocyte and monocyte to lymphocyte ratios in the diagnosis of bacterial infection in patients with fever

PURPOSE

To study the role of the neutrophil:lymphocyte ratio (NLR) and monocyte:lymphocyte ratio (MLR) in discriminating between different patient groups hospitalized for fever due to infection and those without infection.

METHODS

For 299 patients admitted to hospital for fever with unknown cause, a number of characteristics including NLR and MLR were recorded. These characteristics were used in a multiple multinomial regression analysis to estimate the probability of a final diagnostic group of bacterial, viral, clinically confirmed, or no infection.

RESULTS

Both NLR and MLR significantly predicted final diagnostic group. Being highly correlated, however, both variables could not be retained in the same model. Both variables also interacted significantly with duration of fever. Generally, higher values of NLR and MLR indicated larger probabilities for bacterial infection and low probabilities for viral infection. Patients with septicemia had significantly higher NLR compared to patients with other bacterial infections with fever for less than one week. White blood cell counts, neutrophil counts, and C-reactive proteins did not differ significantly between septicemia and the other bacterial infection groups.

CONCLUSIONS

NLR is a more useful diagnostic tool to identify patients with septicemia than other more commonly used diagnostic blood tests. NLR and MLR may be useful in the diagnosis of bacterial infection among patients hospitalized for fever.

Can we predict the prognosis of COPD with a routine blood test?

BACKGROUND

The major characteristic of COPD is systemic inflammation. The parameters such as neutrophil-to-lymphocyte ratio (NLR) and eosinophil-to-basophil ratio (EBR) in routine blood test (RBT) are considered to be the underlying biomarkers of inflammation. We hypothesized that the prognosis of patients with COPD can be predicted with RBT.

METHODS

Patients with COPD in stable stage were enrolled. The RBT, pulmonary function testing (PFT), BODE index, C-reactive protein (CRP), procalcitonin, and erythrocyte sedimentation rate (ESR) were performed at enrollment and every follow-up once in every 3 months during the 24-month follow-up period. Meanwhile, exacerbation count and mortality incidence were recorded. The correlation between the prognostic biomarkers and the prognosis of patients was analyzed.

RESULTS

The NLR and EBR in RBT have a significant correlation with the severity of patients with COPD. The NLR is an independent predictor for mortality and the EBR is an independent predictor for exacerbation.

CONCLUSION

As an inexpensive, accessible, and convenient assay, RBT may be used as a practical means in the prediction of prognosis of patients with COPD in future clinical settings.

Association of the Neutrophil-to-Lymphocyte Ratio with Lung Function and Exacerbations in Patients with Chronic Obstructive Pulmonary Disease

BACKGROUND

The ratio of neutrophils to lymphocytes (NLR) is a widely available marker of inflammation. Several types of inflammatory cells and mediators have been found to be involved in the progression of chronic obstructive pulmonary disease (COPD). We sought to evaluate the association of the NLR with severity of airflow limitation and disease exacerbations in a COPD population.

METHODS

We analyzed 885 patients from the Korean COPD Subtype Study cohort that recruited subjects with COPD from 44 referral hospitals. We determined the relationship of NLR levels to severity of lung function using a linear regression model. In addition, we analyzed the experiences of COPD exacerbation according to the NLR quartiles.

RESULTS

NLR levels were inversely associated with severity of airflow limitation as measured by FEV1% predicted and absolute values after adjustments for age, gender, body mass index, pack-years of smoking, and the use of inhaled corticosteroid (P<0.001, respectively). In the multivariate binary regression model, the NLR 4th quartile (vs. 1st quartile) was found to be a significant predictor of exacerbations during 1-year follow-up (OR = 2.05, 95% CI = 1.03 to 4.06, P = 0.041). Adding an NLR to FEV1 significantly improved prediction for exacerbations during 1-year follow-up as measured by the net reclassification improvement (NRI = 7.8%, P = 0.032) and the integrated discrimination improvement (IDI = 0.014, P = 0.021).

CONCLUSIONS

The NLR showed a significant inverse relationship to airflow limitation and was a prognostic marker for future exacerbations in patients with COPD.

The Importance of Neutrophil-to-Lymphocyte Ratio in Chronic Obstructive Pulmonary Disease

OBJECTIVES

Chronic obstructive pulmonary disease (COPD) is a common lung disease characterized by airflow limitation and systemic inflammation. Recently, neutrophil-to-lymphocyte ratio (NLR) has gathered increasing interest in the detection of inflammation in inflammatory diseases. This study aimed to investigate the role of NLR in COPD for identifying the detection of inflammation and recognition of acute exacerbation.

MATERIAL AND METHODS

The laboratory results of 103 COPD patients were included into the study, of which 47 patients were in acute exacerbation and 56 patients were at stable period, and there were 40 gender and age-matched healthy controls. Complete blood count (CBC), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were evaluated. NLR was calculated from CBC.

RESULTS

NLR values of patients with COPD (both acutely exacerbated and stable) were found significantly higher than those of the controls (p< 0.001, p< 0.05; respectively). In all patients with COPD, NLR values positively correlated with serum CRP (r= 0.641, p< 0.001) and ESR (r= 0.276, p= 0.005) levels and negatively correlated with forced vital capacity (r= -0.20, p= 0.043) and forced expiratory volume in the 1st second (r= -0.288, p= 0.003). For an NLR cutoff of 3.34, sensitivity for detecting exacerbation of COPD was 78.7% and specificity was 73.2% (AUC 0.863, p< 0.001).

CONCLUSION

Our results suggest that NLR may be considered as a reliable and simple indicator in the determination of increased inflammation in patients with COPD. Furthermore, NLR could be useful for the early detection of possible acute exacerbations in patients with COPD.

The Neutrophil to Lymphocyte Ratio Is Related to Disease Severity and Exacerbation in Patients with Chronic Obstructive Pulmonary Disease

Objective Although chronic obstructive pulmonary disease (COPD) is characterized by systemic inflammation, the association between the neutrophil to lymphocyte ratio (NLR; an indicator of inflammation) and the clinical status of COPD has not been well studied. We hypothesized that the NLR is associated with disease severity and exacerbation in COPD patients. Methods We performed blood testing, pulmonary function testing, chest computed tomography, a body composition analysis, and a 6-minute walk test and applied the modified Medical Research Council (MMRC) dyspnea scale for 141 stable COPD patients. In addition, we calculated the body mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) index to evaluate the disease severity. Finally, we examined the association between the NLR and clinical parameters in stable COPD patients, and we further investigated changes in the NLR between exacerbation and the stable state. Results The NLR was positively correlated with the BODE index, extent of emphysema, and MMRC score (p<0.001 for all), while inversely correlated with airflow obstruction (p<0.001), body mass index (p<0.001), fat-free mass index (p=0.001), and the 6-minute walk distance (p<0.001). We obtained the NLR during exacerbation from 49 patients. The NLR was significantly higher at exacerbation compared to the stable state (p<0.001). Conclusion The NLR was associated with disease severity and exacerbation in COPD patients. Therefore, the usefulness of the NLR in COPD patients should be elucidated in clinical settings in future investigations.