Exacerbation of Chronic Obstructive Pulmonary Disease

Predictive value of neutrophil-to-lymphocyte ratio for adverse outcomes in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease: A retrospective study

Chronic obstructive pulmonary disease (COPD) stands as one of the leading causes of mortality worldwide. Acute exacerbations of COPD (AECOPD) lead to rapid respiratory function decline and worsened disease status. Despite recent studies, the ability of the neutrophil-to-lymphocyte ratio (NLR) to predict outcomes in patients with COPD remains controversial. We investigated the predictive value of NLR for adverse outcomes in hospitalized patients with AECOPD. A retrospective study was conducted at the Department of Pulmonary Medicine, Cho Ray Hospital (Vietnam) from November 2019 to November 2021. The study extracted data from patients diagnosed with AECOPD at discharge and met the inclusion criteria. NLR is calculated by dividing the number of neutrophils by the number of lymphocytes in the peripheral blood test. Adverse outcomes are defined as invasive mechanical ventilation, admission to intensive care unit, or in-hospital mortality. Multivariable regression analysis was conducted to identify variables predicting adverse outcomes. The cutoff, sensitivity, specificity, area under the curve, and receiver operating characteristic of NLR were determined for predicting adverse outcomes. Two hundred eighty-seven patients with AECOPD were included in the final analysis, with a mean age of 70.9, and males comprising 92.7%. The rate of adverse outcomes was 15.7%. Multivariable logistic regression identified reduced consciousness at admission (adjusted odds ratio = 0.08, 95% confidence interval [CI]: 0.02-0.38, P = .001) and high NLR (adjusted odds ratio = 1.17, 95% CI: 1.10-1.24, P < .001) as predictors of adverse outcomes. The receiver operating characteristic of NLR's predictive value yielded an area under the curve of 0.877 (95% CI: 0.83-0.93). An NLR cutoff of 11.0 predicted adverse outcomes with a sensitivity of 80.0%, specificity of 77.7%, and an odds ratio of 13.9 (95% CI: 6.3-30.7), P < .001. NLR is a simple, routine, and cost-effective tool for predicting adverse outcomes in hospitalized patients with AECOPD. Future studies should evaluate the kinetics of NLR in predicting treatment response in patients with AECOPD.

Early detection and prediction of acute exacerbation of chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) is characterized by persistent respiratory symptoms and airflow limitation. Acute exacerbation of COPD (AECOPD) is an acute worsening of respiratory symptoms, which needs additional treatment and can result in worsening health status, increasing risks of hospitalization and mortality. Therefore, it is necessary to early recognize and diagnose exacerbations of COPD. This review introduces the updated definition of COPD exacerbations, the current clinical assessment tools, and the current potential biomarkers. The application of mobile health care in COPD management for early identification and diagnosis is also included in this review.

Knockdown of NRSF Alleviates Ischemic Brain Injury and Microvasculature Defects in Diabetic MCAO Mice

Diabetes is one of the well-established risk factors of stroke and is associated with a poor outcome in patients with stroke. Previous studies have shown that the expression of neuron restrictive silencer factor (NRSF) is elevated in diabetes as well as ischemic stroke. However, the role of NRSF in regulating an outcome of diabetic ischemic stroke has not been completely understood. Here, we hypothesized that diabetes-induced NRSF elevation can aggravate brain injury and cognition impairment in ischemic stroke. The diabetic ischemic stroke mice model was established by 8 weeks of high-fat-diet feeding and 5 days of streptozotocin injection followed by 30 min of middle cerebral artery occlusion (MCAO). We found that diabetes enhanced the MCAO-induced elevation of NRSF in the hippocampus in accompany with an elevation of its corepressors, HDAC1, and mSin3A, and decrease of β-TrCP. By using histological/immunofluorescence staining and neurobehavioral testing, our results showed that the brain damage and learning/memory impairment were aggravated in diabetic ischemic mice but significantly attenuated after stereotaxic injection of NRSF-shRNA. Meanwhile, by performing whole-brain clearing with PEGASOS, microvascular reconstruction, western blotting, and ELISA, we found that NRSF-shRNA markedly alleviated the vasculature disorders and rescued the suppression of NRP-1, VEGF, and VEGFR2 in the hippocampus of diabetic ischemic mice. Therefore, our results demonstrated for the first time that the elevation of hippocampal NRSF plays an important role in alleviating brain injury and cognitive disabilities in diabetic ischemic mice, potentially via the reduction of NRP-1/VEGF signaling.

Usefulness of Glucose to Lymphocyte Ratio to Predict in-Hospital Mortality in Patients with AECOPD Admitted to the Intensive Care Unit

The purpose of this study was to investigate the relationship between glucose to lymphocyte ratio (GLR) and the outcome of acute exacerbation chronic obstructive pulmonary disease (AECOPD) patients admitted to the intensive care unit (ICU). This study included 3573 patients from the eICU Collaborative Research Database (eICU-CRD) and 926 AECOPD patients admitted to ICU from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. The optimal cutoff value for GLR was 5.6. Kaplan-Meier analysis demonstrated that patients in lower GLR (< 5.6) group showed a better overall survival than patients in higher GLR (≥ 5.6) group in all sets. Multivariate Cox regression analysis demonstrated that age, Sequential Organ Failure Assessment (SOFA) score, SpO2, albumin and GLR are independent predictors of poor overall survival in the training cohort and were incorporated into the nomogram for in-hospital mortality as independent factors. The nomogram exhibited excellent discrimination with C-indexes in training cohort, internal validation and external validation cohort were (0.801, 95%CI: 0.769-0.863), (0.805, 95%CI: 0.759-0.851) and (0.811, 95%CI: 0.772-0.850), respectively. The calibration plot indicated an adequate fit of the nomogram for predicting the risk of in-hospital mortality in all sets. Moreover, the ROC analyses demonstrated that the discrimination abilities of GLR were better than other blood-based inflammatory biomarkers. As an easily available biomarker, GLR can independently predict the in-hospital mortality in AECOPD patients admitted to ICU. The nomogram combining GLR with other significant indicators exhibited excellence predictive performance for in-hospital mortality.

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.

Smoking shifts human small airway epithelium club cells toward a lesser differentiated population

The club cell, a small airway epithelial (SAE) cell, plays a central role in human lung host defense. We hypothesized that subpopulations of club cells with distinct functions may exist. The SAE of healthy nonsmokers and healthy cigarette smokers were evaluated by single-cell RNA sequencing, and unsupervised clustering revealed subpopulations of SCGCB1A1⁺KRT5^loMUC5AC^- club cells. Club cell heterogeneity was supported by evaluations of SAE tissue sections, brushed SAE cells, and in vitro air-liquid interface cultures. Three subpopulations included: (1) progenitor; (2) proliferating; and (3) effector club cells. The progenitor club cell population expressed high levels of mitochondrial, ribosomal proteins, and KRT5 relative to other club cell populations and included a differentiation branch point leading to mucous cell production. The small proliferating population expressed high levels of cyclins and proliferation markers. The effector club cell cluster expressed genes related to host defense, xenobiotic metabolism, and barrier functions associated with club cell function. Comparison of smokers vs. nonsmokers demonstrated that smoking limited the extent of differentiation of all three subclusters and altered SAM pointed domain-containing Ets transcription factor (SPDEF)-regulated transcription in the effector cell population leading to a change in the location of the branch point for mucous cell production, a potential explanation for the concomitant reduction in effector club cells and increase in mucous cells in smokers. These observations provide insights into both the makeup of human SAE club cell subpopulations and the smoking-induced changes in club cell biology.

Haemophilus influenzae persists in biofilm communities in a smoke-exposed ferret model of COPD

Rationale

Non-typeable Haemophilus influenzae (NTHi) is a common inhabitant of the human nasopharynx and upper airways that can cause opportunistic infections of the airway mucosa including bronchopulmonary infections in patients with chronic obstructive pulmonary disease (COPD). It is clear that opportunistic infections contribute significantly to inflammatory exacerbations of COPD; however, there remains much to be learned regarding specific host and microbial determinants of persistence and/or clearance in this context.

Methods

In this study, we used a recently described ferret model for COPD, in which animals undergo chronic long-term exposure to cigarette smoke, to define host–pathogen interactions during COPD-related NTHi infections.

Results

NTHi bacteria colonised the lungs of smoke-exposed animals to a greater extent than controls, and elicited acute host inflammation and neutrophilic influx and activation, along with a significant increase in airway resistance and a decrease in inspiratory capacity consistent with inflammatory exacerbation; notably, these findings were not observed in air-exposed control animals. NTHi bacteria persisted within multicellular biofilm communities within the airway lumen, as evidenced by immunofluorescent detection of bacterial aggregates encased within a sialylated matrix as is typical of NTHi biofilms and differential bacterial gene expression consistent with the biofilm mode of growth.

Conclusions

Based on these results, we conclude that acute infection with NTHi initiates inflammatory exacerbation of COPD disease. The data also support the widely held hypothesis that NTHi bacteria persist within multicellular biofilm communities in the lungs of patients with COPD.

Infection of smoke-exposed ferrets with COPD results in mucus obstruction and respiratory symptoms as in patients, and the bacteria are in a distinct mode of growth consistent with biofilmshttps://bit.ly/3euXpbQ

Effects of Ambient Temperature on Acute Exacerbations of Chronic Obstructive Pulmonary Disease: Results from a Time-Series Analysis of 143318 Hospitalizations

Purpose

To evaluate the associations between acute exacerbations of chronic obstructive pulmonary disease (AECOPD) hospitalizations and daily mean temperature (Tmean) as well as daily apparent temperature (AT), and to explore the practical values of these two indices in policymaking and patient education.

Methods

Daily AECOPD hospitalizations and Meteorological data in Beijing were obtained between 2013 and 2016. Distributed lag non-linear model was adopted to investigate the association between daily ambient temperature and AECOPD hospitalizations. The cumulative effects of cold/hot temperature were abstracted. For the extreme and moderate low-temperature effect estimates, we, respectively, computed the RR of AECOPD hospitalizations at the 1st and 10th percentiles of temperature in comparison with that at the 25th percentile of temperature. For the extreme and moderate high temperature effect estimates, we, respectively, computed the RR of AECOPD hospitalizations at the 99th and 90th percentiles of temperature in comparison with that at the 75th percentile of temperature.

Results

During the study period, 143, 318 AECOPD hospitalizations were collected. A reverse J-shape relationship was found between temperature and AECOPD hospitalizations. When comparing the effect of Tmean, higher RRs were associated with increases in AT on AECOPD hospitalizations but a lower value of Akaike’s Information Criterion for quasi-Poisson (Q-AIC). The RR of extremely low temperature of Tmean and AT were 1.55 (95% CI: 1.21,2.00) and 2.08 (95% CI: 1.44,3.01), respectively. Moderate low temperature also had an adverse impact on AECOPD hospitalizations. No associations were found between high temperature and AECOPD risk. We found the females and those aged <65 years to be more susceptible to temperature change.

Conclusion

Lower temperature is associated with a higher risk for AECOPD hospitalizations. Ambient temperature is probably a better predictor in terms of quantifying risk than mean temperature when studying temperature impact on health.

Evaluation of plasma antimicrobial peptide LL-37 and nuclear factor-kappaB levels in stable chronic obstructive pulmonary disease

Background

Antimicrobial peptides are effectors of host defence against infection and inflammation and can encourage wound repair.

Objectives

The objectives of this study were to investigate the plasma antimicrobial peptide LL-37 and nuclear factor-kappaB (NF-κB) levels in patients with stable COPD compared with a control group and to highlight their importance in immune inflammation.

Methods

One hundred and thirty-eight stable COPD patients and 33 control subjects were enrolled in the study. The COPD patients were classified into four groups based on FEV₁ (groups I-IV) and also divided into "low-risk and high-risk" groups (groups A-B [low risk], C-D [high risk]).

Results

Plasma LL-37 levels were significantly lower while plasma NF-κB levels of the COPD patients were significantly higher than those of the control subjects (P<0.001, both). LL-37 levels were significantly lower in group IV than in groups I, II, and III (P<0.01, all). NF-κB levels were significantly higher in groups III and IV than in groups I and II (P<0.05, both). There was a positive correlation between FEV₁ and FEV₁/FVC in all COPD patients (r=0.742, P<0.001) and in group D (r=0.741, P<0.001). Furthermore, there was an inverse correlation between LL-37 and NF-κB in both the groups C (r=-0.566, P<0.001) and D (r=-0.694, P<0.001) and group C+D combined (r=-0.593, P<0.001). Furthermore, in group C, LL-37 and FEV₁ were positively correlated (r=0.633, P<0.001).

Conclusion

Our study indicated that plasma LL-37 and NF-κB may play an important role in chronic immune inflammation. Decreased LL-37 levels may be particularly high risk for patients in stage IV disease. The role of LL-37 as a target for treatment of the immune system and COPD must be widely evaluated.

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.

The human viral challenge model: accelerating the evaluation of respiratory antivirals, vaccines and novel diagnostics

The Human Viral Challenge (HVC) model has, for many decades, helped in the understanding of respiratory viruses and their role in disease pathogenesis. In a controlled setting using small numbers of volunteers removed from community exposure to other infections, this experimental model enables proof of concept work to be undertaken on novel therapeutics, including vaccines, immunomodulators and antivirals, as well as new diagnostics.Crucially, unlike conventional phase 1 studies, challenge studies include evaluable efficacy endpoints that then guide decisions on how to optimise subsequent field studies, as recommended by the FDA and thus licensing studies that follow. Such a strategy optimises the benefit of the studies and identifies possible threats early on, minimising the risk to subsequent volunteers but also maximising the benefit of scarce resources available to the research group investing in the research. Inspired by the principles of the 3Rs (Replacement, Reduction and Refinement) now commonly applied in the preclinical phase, HVC studies allow refinement and reduction of the subsequent development phase, accelerating progress towards further statistically powered phase 2b studies. The breadth of data generated from challenge studies allows for exploration of a wide range of variables and endpoints that can then be taken through to pivotal phase 3 studies.We describe the disease burden for acute respiratory viral infections for which current conventional development strategies have failed to produce therapeutics that meet clinical need. The Authors describe the HVC model's utility in increasing scientific understanding and in progressing promising therapeutics through development.The contribution of the model to the elucidation of the virus-host interaction, both regarding viral pathogenicity and the body's immunological response is discussed, along with its utility to assist in the development of novel diagnostics.Future applications of the model are also explored.

COPD prevalence and hospital admissions in Galicia (Spain). An analysis using the potential of new health information systems

INTRODUCTION AND OBJECTIVES

Chronic obstructive pulmonary disease (COPD) is a major public health problem. The aim of this study was to ascertain the prevalence of COPD and whether such prevalence was positively or negatively associated with COPD admissions, using all the data of a regional health care system.

MATERIALS AND METHODS

We designed a descriptive cross-sectional study which included all subjects aged over 45 years, diagnosed with COPD in primary care in 2013. We also calculated the number of such patients who had a record of hospital admissions due to this disease. COPD prevalence and incidence of admissions were calculated. Poisson regression models were then used to analyse the association between cases with diagnosis of COPD and admissions due to COPD, by sex, adjusting for socio-demographic variables and distance to hospital. Sensitivity subanalyses were performed by reference to the respective municipal rurality indices.

RESULTS

Median municipal prevalence of COPD was 5.29% in men and 2.19% in women. Among patients with COPD, 28.22% of men and 16.00% of women had at least one hospital admission. The relative risk of admission per unit of the standardised prevalence ratio was 0.37 (95% CI 0.34-0.41) for men and 0.39 (95% CI 0.34-0.45) for women.

CONCLUSIONS

There is a significant negative association between COPD prevalence and hospital admissions due to this disease. The proportion of admissions is lower in municipalities lying furthest from hospitals. There is considerable municipal variability in terms of COPD prevalence and proportion of admissions. In-depth attention should be given to disease-management training programmes.

Effect of Pingchuan Guben decoction on patients with chronic obstructive pulmonary disease: Results from a randomized comparative effectiveness research trial

Chronic obstructive pulmonary disease (COPD) is known to be a systemic low-grade ongoing inflammation exerting major health and economic burden worldwide. Complementary and alternative medicines, such as Traditional Chinese Medicine, are widely used for the treatment of patients with COPD. The present study was designed to investigate the efficacy of Pingchuan Guben decoction on patients with COPD through a double-blinded, open-labeled, randomized controlled trial. A total of 86 patients were randomly assigned to two groups, with 43 patients in the intervention group and 43 cases in the control group. The patients in the control group were treated with conventional western medicine, and the intervention group received a combination of conventional western medicine and Pingchuan Guben decoction. After 12 weeks of treatment, the mean 6-minute walking distance, forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC) and FEV1/FVC in the intervention group were significantly higher than those of the control group (P<0.05). The levels of inflammation factors and protease molecules were significantly ameliorated in the intervention group compared with the control group (P<0.05). The levels of Kelch-like ECH-associated protein 1 (Keap1), nuclear factor-E2-related factor-2 (Nrf2), superoxide anions, malondialdehyde, glutathione S-transferase and glutathione peroxidase were significantly more improved in the intervention group compared with those in the control group over the 12-week study period (P<0.05). Therefore, combinations of western medicine with Pingchuan Guben decoction may exert therapeutic effects on patients with COPD via modulations of inflammation factors and protease molecules, as well as the activation of the Keap1/Nrf2 signaling pathway.

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.