Difference in systemic inflammation and predictors of acute exacerbation between smoking-associated COPD and tuberculosis-associated COPD

A Novel Inflammatory Indicator for Tuberculosis-Associated Obstructive Pulmonary Disease (TOPD): The Systemic Inflammatory Response Index (SIRI)

Background

The development of chronic obstructive pulmonary disease (COPD) following tuberculosis (TB) is known as tuberculosis-associated obstructive pulmonary disease (TOPD). This study aimed to explore the predictive value of inflammatory indicators for TOPD in TB patients.

Methods

Data for this cross-sectional study were collected between January 2014 and January 2022 at Wuhan Jinyintan Hospital. The ratio of inflammatory indicators, including Systemic Inflammatory Response Index (SIRI), C-reactive protein-to-lymphocyte ratio (CLR), eosinophil count-to-lymphocyte count ratio (ELR), were calculated. Univariate and multivariate logistic regression analyses were conducted to explore the association between the ratio of inflammatory indicators and TOPD. Furthermore, the relationship between the ratio of inflammatory indicators and TOPD was investigated using propensity score matching (PSM) and receiver operating characteristic (ROC) curve analysis was performed to evaluate their predictive value for TOPD.

Results

The present study included a total of 737 patients, of whom 83 participants (11.26%) had TOPD. Sixty-nine TOPD patients and 69 non-TOPD (NTOPD) patients were successfully matched. Univariate and multivariable logistics regression analysis, conducted before and after PSM, revealed that SIRI was independently significantly associated with an increased risk of TOPD. The area under curve (AUC) of SIRI were 0.702 and 0.668 before and after PSM, respectively. Additionally, patients were stratified into four different groups based on SIRI quartiles for further analysis. The prevalence of TOPD in TB patients showed an increase with higher SIRI values, both before and after PSM.

Conclusion

Levels of inflammatory indicators were higher in TOPD patients when compared to NTOPD patients. SIRI may be a simple and useful inflammatory index for assessing TOPD, and TB patients with higher values of SIRI are more likely to be high-risk group for TOPD.

Characteristics of Serum Autoantibody Repertoire and Immune Subgroup Variation of Tuberculosis-Associated Obstructive Pulmonary Disease

Background

Studying the potential etiology and pathogenesis of tuberculosis-associated chronic obstructive pulmonary disease (TOPD) from an autoimmunity perspective may provide insights into peripheral blood autoantibodies and immune cells, as well as their interactions.

Methods

This study examined the serum autoantibody repertoire in healthy individuals, patients with chronic obstructive pulmonary disease (COPD), patients with pulmonary tuberculosis (TB), and TOPD patients using the HuProtTM protein chip. Autoantigens in the peripheral blood of TOPD patients were verified using ELISA assay. Various epitopes and immune simulation were predicted using bioinformatic methods. Flow cytometry was employed to detect macrophages(Mφ), T cells, and innate lymphoid cells (ILCs) in the peripheral blood.

Results

COPD patients displayed distinct alterations in their IgG and IgM autoantibodies compared to the other groups. GeneOntology (GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses revealed that these autoantibodies were associated with regulating macrophages, T cells, and B cells. ELISA results confirmed the upregulation of expression of proliferating cell nuclear antigen (PCNA), Mitogen-Activated Protein Kinase 3 antigen (MAPK3), and threonine protein kinase 1 antigen (AKT1) proteins in the peripheral blood of TOPD patients. Bioinformatic analysis predicted multiple potential epitopes in Th, CTL, and B cells. Immune simulation results demonstrated that PCNA, MAPK3, and AKT1 can activate innate and adaptive immune responses and induce the expression of different cytokines, such as IFN-g and IL-2. Furthermore, data obtained from flow cytometry assay revealed an upregulation in the face of Th1 cells in the peripheral blood of TOPD patients.

Conclusion

Tuberculosis infection can effectively induce autoimmune responses, contributing to increased expression of Th1 cells and associated cytokines, ultimately leading to immune dysregulation. Furthermore, the accumulation of pulmonary inflammatory response facilitates the progression of TOPD and is helpful for the clinical diagnosis and the development of targeted therapeutic drugs for this disease.

Airflow obstruction and small airway dysfunction following pulmonary tuberculosis: a cross-sectional survey

OBJECTIVES

Pulmonary function impairment and chronic respiratory symptoms after tuberculosis are relatively common in low-income and middle-income countries. We aimed to estimate the impact of post-tuberculosis (post-TB) on pulmonary function.

METHODS

This large cross-sectional, population-based study included subjects aged 15 years or older with technically acceptable postbronchodilator spirometry measurements. Post-TB was diagnosed on the basis of radiological evidence and/or medical history. Airflow obstruction was defined as a postbronchodilator forced expiratory volume in 1 s/forced vital capacity ratio below the lower limit of normal of Global Lung Function Initiative (GLI) lung function equations. Small airway dysfunction was diagnosed if at least two of the following indicators were less than 65% of predicted: maximal mid-expiratory flow, forced expiratory flow (FEF) 50% or FEF 75%.

RESULTS

In this population sample (N=8680, mean age: 40.1 years), 610 (7.0% (95% CI 6.5 to 7.6) participants were post-TB. Post-TB subjects had more frequent respiratory symptoms (46.8% vs 28.3%). Among post-TB subjects, 130 (21.3% (95% CI 18.1 to 24.8)) had airflow obstruction; OR of airflow obstruction was significantly associated with post-TB after adjustment for other confounding factors (OR 1.31, 95% CI 1.05 to 1.62). Post-TB was also associated with small airway dysfunction (OR 1.28, 95% CI1.07 to 1.53), which was present in 297 (48.9% (95% CI 33.9 to 53.0)) post-TB subjects.

CONCLUSIONS

Our findings support existing knowledge that post-TB is positively associated with pulmonary function impairment and make for frequent respiratory symptoms. Post-TB should be considered as a potentially important cause of airflow obstruction and respiratory symptoms in patients originating from countries with a high burden of tuberculosis.

Effects of Smoking on Inflammatory-Related Cytokine Levels in Human Serum

Cardiovascular and respiratory diseases, and several cancers resulting from tobacco smoking, are initially characterized by chronic systemic inflammation. Cytokine imbalances can result in inflammation, making it important to understand the pathological mechanisms behind cytokine production. In this study, we collected blood samples from 78 healthy male volunteers, including non-smokers (n = 30), current smokers (n = 30), and ex-smokers (n = 18), and utilized the liquid suspension chip technique to investigate and compare the expression levels of 17 cytokines and chemokines in the human serum of these volunteers. The results demonstrated that the expression levels of CXCL9/MIG and sIL-6R significantly increased after smoking, and continued to increase after quitting smoking. The expression levels of TARC, ITAC, and sVEGFR-3 increased after smoking but decreased after quitting smoking; the expression level of SAA significantly decreased after smoking and showed an upward trend after quitting smoking. Seven cytokines (IL-1β, BCA-1, TNF-α, CRP, ENA-78, MDC, and TNFRII) did not vary between the three groups, while four cytokines (IL-1α, IL-6, IL-8, and SCF) were not detected in any serum sample. In conclusion, this study assessed the physiological production of cytokines and chemokines, highlighting the differences in each due to smoking status. Our results could help evaluate the early development of smoking-related chronic diseases and cancers.

Serum interleukin-6 in chronic obstructive pulmonary disease patients and its relation to severity and acute exacerbation

Background and objectives

The role of interleukins in the severity and clinical profile of chronic obstructive pulmonary disease (COPD) is not known, but evidence supports the contribution of systemic inflammation to disease pathophysiology. This study evaluated the relationship of serum interleukin-6 (IL-6) to the severity and clinical parameters of COPD.

Aim of work

The aim of the work is to estimate the level of IL-6 in COPD patients and its relation to COPD severity and acute exacerbation.

Patients and method

We analyzed 45 COPD patients and 45 normal population as control. We estimate the IL-6 level by ELISA and correlate it with the severity and frequency of COPD exacerbation.

Results

In the current study, we noticed that IL-6 level was high in COPD patients and in those who experience frequent exacerbation. Also, IL-6 show a relation with the parameter of pulmonary function test; there is a statistically significant negative correlation with p-value < 0.05 between the level of IL-6 and the forced expired volume in 1 s/forced vital capacity (EFV1/FVC) among cases with COPD, which indicated that decrease in EFV/FVC will associate with the increase in IL-6 level.

Conclusions

The study revealed that serum IL-6 level elevated with increasing severity of airflow limitation in COPD patients, particularly in acute exacerbation phase. This increase was associated with a reduced quality of life and increased severity of hypoxemia.

Metabolic Fingerprinting Uncovers the Distinction Between the Phenotypes of Tuberculosis Associated COPD and Smoking-Induced COPD

Background: Although smoking is considered the main cause of chronic obstructive pulmonary disease (COPD), several other risk factors, including pulmonary tuberculosis (TB), contribute significantly to disease causation, particularly in developing countries. However, the underlying pathogenesis of TB-associated COPD (T-COPD) is unclear. Moreover, the need for prompt diagnosis and treatment of T-COPD to decrease the future burden of inflammation is underestimated. This study aimed to identify distinctive endogenous metabotypes of T-COPD, compared to smoking-associated COPD (S-COPD). Methods: Cross-sectional metabolomic analyses and clinical examinations of serum samples were performed for three groups of 168 male subjects: T-COPD (n = 59), S-COPD (n = 70), and healthy normal controls (n = 39). To retain a broad spectrum of metabolites, we performed technically distinct analyses (global metabolomic profiling using LC-QTOFMS and targeted analyses using LC-MS/MS). Results: Higher levels of IL-6 and C-reactive protein and St. George Respiratory Questionnaire scores were seen in the T-COPD group, compared to those in the S-COPD group. Global metabolomic profiling showed elevated metabolites, including arachidonic and eicosanoic acids, in the T-COPD group. Typical changes in tryptophan catabolism were observed through targeted profiling. Additionally, in the T-COPD group, kynurenine was elevated, and serotonin levels were reduced; therefore, indoleamine dioxygenase (IDO)/tryptophan hydroxylase (TPH) activities were dysregulated. Correlation analyses showed that changes in oxylipins were positively correlated with serum levels of IL-6 and C-reactive protein. Conclusion: Patients with TB-related COPD have enhanced inflammatory responses that may be linked to fatty acid pathways and tryptophan catabolism, which could be novel therapeutic targets for T-COPD.

Association between plasma interleukin-33 level and acute exacerbation of chronic obstructive pulmonary disease

Background

The role of interleukin (IL)-33 in patients with chronic obstructive pulmonary disease (COPD) has not been well elucidated. The aim of this study is to analyze the association between plasma IL-33 level and acute exacerbation of COPD.

Methods

Plasma IL-33 was measured in 62 COPD patients during their stable state. Patients were prospectively followed up for 1 year. The expression of IL-33 was measured in lung tissue obtained from 38 patients who underwent surgery.

Results

The number of exacerbations was significantly higher in the high plasma IL-33 group compared with the low plasma IL-33 group. On Poisson regression analysis, high plasma IL-33 was associated with increased risk of exacerbation (incidence rate ratio = 2.166, P = 0.043). The expression of IL-33 in the lung was higher in COPD patients than in controls. The expression of IL-33 was significantly correlated with smoking pack years (R = 0.45, P < 0.01) and Forced expiratory volume in 1 s (%) (R = − 0.58, P < 0.01).

Conclusion

The plasma level of IL-33 in patients with COPD was significantly associated with the risk of exacerbation in prospective follow up. The expression of IL-33 in the lung was positively correlated with smoking and negatively correlated with lung function.

Predictive role of interleukin-6 and CAT score in mechanical ventilation in patients with chronic obstructive pulmonary disease at the acute exacerbation stage in the emergency department

BACKGROUND

The study aimed to evaluate the predictive role of interleukin-6 (IL-6) and chronic obstructive pulmonary disease (COPD) assessment test (CAT) score in mechanical ventilation (MV) in COPD patients at the acute exacerbation stage in the emergency department (ED).

METHODS

For a one-year period, among adult patients in the ED who met the criteria of acute exacerbation of COPD, 158 who received MV within 48 hours after admission were compared to 294 who didn't require MV within the same period after admission. IL-6 level and CAT score were compared between the two groups. The predicted value of IL-6 and CAT score was assessed by logistic regression analysis and a receiver operating characteristic (ROC) curve.

RESULTS

The IL-6 and CAT scores in the 158 MV patients were much higher than those without. IL-6 and CAT scores were independent predictors of MV within 48 hours using logistic regression analysis (IL-6: odds ratio [OR] 1.053, 95% confidence interval [CI] 1.039-1.067, P<0.001; CAT score: OR 1.122, 95% CI 1.086-1.159, P<0.001). The combination of IL-6 and CAT scores (area under ROC curve [AUC] 0.826, 95% CI 0.786-0.866, P<0.001) improved the accuracy of predicting MV within 48 hours when compared with IL-6 (AUC 0.752, 95% CI 0.703-0.800, P<0.001) and CAT scores alone (AUC 0.739, 95% CI 0.692-0.786, P<0.001). The sensitivity and specificity were 69.6%, 74.1%, 75.32% and 63.6%, respectively.

CONCLUSION

The combined of IL-6 and CAT scores is useful for evaluating the risk of COPD patients at acute exacerbation in ED, and can provide a predictive value for MV or not within 48 hours.

Endotype-driven prediction of acute exacerbations in chronic obstructive pulmonary disease (EndAECOPD): protocol for a prospective cohort study

INTRODUCTION

Current strategies for the prevention of acute exacerbations in chronic obstructive pulmonary disease (COPD) are primarily based on clinical measurements but fail to target the pathophysiological mechanisms, namely endotypes, of the disease. Studies identifying endotypes underlying exacerbation susceptibility and discovering specific biomarkers may lead to the development of targeted therapeutics but are lacking. This study aims to assess a broad spectrum of biomarkers at multiple biological levels (genetics, airway inflammation and respiratory microbiome) for their ability in predicting acute exacerbations of COPD, thus enables high-resolution disease endotyping and may lead to precision treatment of the disease.

METHODS AND ANALYSIS

In this prospective cohort study, participants with stable COPD (n=600) will be recruited and assessed for demographics, symptom scores, spirometry, medication use and comorbidities at baseline. Blood will be obtained for genotyping variants in a panel of nine genes. Induced sputum will be collected for the profile of microbiota using 16S rRNA gene sequencing, quantification of bacterial load, inflammatory mediators assay and sputum cytometry. Participants will be followed up for their exacerbations till 12 months and reassessed for the clinical measurements as baseline. The primary outcomes are total number of exacerbations, severe exacerbations, moderate exacerbations and time to first exacerbation. The secondary outcomes are changes in lung function and symptom scores. The effect of biomarkers representing genetic variants, airway inflammation and respiratory microbiome on predicting the frequent exacerbator phenotype and exacerbation frequency will be analysed with multivariable modelling, and time to first exacerbation with a Cox regression model.

ETHICS AND DISSEMINATION

The study has been approved by the Clinical Trial and Biomedical Ethics Committee of West China Hospital of Sichuan University (No. 2018-298). The results of the study will be published on peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR1800019063.