Biomarkers related to respiratory symptoms and lung function in adults with asthma

Dysregulated blood biomarkers in women with acute and chronic respiratory conditions due to air pollutant exposure: An exploratory systematic review

Background

Air pollution exposure poses significant health risks for the general population, but particularly for women with acute and chronic respiratory conditions. Given the increasing global burden of air pollution-related illnesses, understanding these biomarkers is crucial for developing targeted interventions and improving respiratory health outcomes in vulnerable populations. In this systematic review, we aimed to determine potential dysregulated respiratory inflammatory blood biomarker candidates in adult female patients who experience varying levels and sources of inhaled pollutant exposure.

Methods

We searched the Cochrane Library, PubMed, and Web of Science with nuanced search terms to retrieve articles published in English between 1 January 2000 and 12 June 2023, to ensure relevancy. We filtered our findings to generate a focussed narrative analysis and used the Risk of Bias In Non-randomized Studies-of Exposures (ROBINS-E) and Risk-of-bias VISualization (robVIS) tools to ensure the validity of the data and the quality of the conclusions being made.

Results

We identified 916 articles from the databases used in our search, 16 of which met the criteria of our focussed narrative analysis. Among blood biomarkers, platelet-activating factor and eosinophilia could be used to assess the severity of asthma conditions, as a lack or reduction thereof indicates specific conditions. Pro-inflammatory cytokines require further validation, as some studies with a high risk of bias have reported conflicting results compared to more recent research on whether these markers are up-regulated or down-regulated. We found one study to be at a very high risk of bias, two had a high risk of bias, one had some concerns of confounding factors which may not have affected their results, and 12 studies had a low risk of bias.

Conclusions

There were narrowed-down blood biomarker candidates that could be used in future research and avenues of research like generating specific microRNA sequences to test for prognostic/diagnostic tests.

Registration

PROSPERO: 42023435721.

Implications of DNA damage in chronic lung disease

DNA plays an indispensable role in ensuring the perpetuation of life and safeguarding the genetic stability of living organisms. The emergence of diseases linked to a wide spectrum of responses to DNA damage has garnered increasing attention within the scientific community. There is growing evidence that patterns of DNA damage response in the lungs are associated with the onset, progression, and treatment of chronic lung diseases such as chronic obstructive pulmonary disease (COPD), asthma, and bronchopulmonary dysplasia (BPD). Currently, some studies have analyzed the mechanisms by which environmental factors induce lung DNA damage. In this article, we summarize inducible factors of lung DNA damage, current indicators, and methods for diagnosing DNA damage in chronic lung diseases and explore repair mechanisms after DNA damage including nonhomologous end-joining and homology-directed repair end joining pathways. Additionally, drug treatments that may reduce DNA damage or promote repair after it occurs in the lungs are briefly described. In general, more accurate assessment of the degree of lung DNA damage caused by various factors is needed to further elucidate the mechanism of lung DNA damage and repair after damage, so as to search for potential therapeutic targets.

Association of systemic immune-inflammation index with asthma and asthma-related events: a cross-sectional NHANES-based study

Background

Asthma is associated with persistent airway inflammation, and numerous studies have investigated inflammatory markers causing asthma. However, the systemic immune-inflammation index (SII) is a novel inflammatory marker, with scarce research reporting on the correlation between SII and asthma and asthma-related events.

Objective

The purpose of this study was to assess the relationship between SII and asthma and asthma-related events (including whether asthma is still present, asthma flare-ups in the past year, and asthma duration) using data from the National Health and Nutrition Examination Survey (NHANES).

Methods

The study utilized data from NHANES 2009-2018 with asthma and asthma-related events as dependent variables and SII as an independent variable. Multifactor logistic regression was employed to assess the correlation between the independent and dependent variables. Smoothed curve-fitting and threshold effect analyses were also carried out to determine the presence of non-linear relationships. Subgroup analyses were then performed to identify sensitive populations.

Results

In this study, we analyzed data from 40,664 participants to elucidate the association between SII and asthma and its related events. The study findings indicated a positive correlation between SII and asthma, with a relative risk increase of 0.03% for asthma incidence per one percentage point increase in SII (OR = 1.0003, 95% CI: 1.0002, 1.0004). For individuals still suffering from asthma, higher SII also indicated a positive correlation with ongoing asthma (OR = 1.0004, 95% CI: 1.0001, 1.0006). However, no statistically significant association was observed between SII and asthma exacerbations within the following year (OR = 1.0001, p > 0.05). When considering the duration of asthma, we observed a slight positive correlation with SII (β = 0.0017, 95% CI: 0.0005, 0.0029). Additionally, a significant non-linear relationship between SII and asthma duration emerged at the threshold of 504.3 (β = 0.0031, 95% CI: 0.0014-0.0048, p = 0.0003). Subgroup analysis revealed a stronger correlation between SII and asthma in male patients (OR = 1.0004, 95% CI: 1.0002-1.0006) and individuals aged 60 and above (OR = 1.0005, 95% CI: 1.0003-1.0007). No gender differences were observed for individuals still suffering from asthma. However, the positive correlation between SII and asthma was more pronounced in participants under 20 years old (OR = 1.0004 in Model 3, 95% CI: 1.0002-1.0006). Specific sensitive subgroups for asthma exacerbation recurrence within the past year were not identified. When considering asthma duration, we observed this association to be significant in male individuals (β = 0.0031 in Model 3, 95% CI: 0.0014-0.0049) as well as individuals aged 20 to 39 (β = 0.0023 in Model 3, 95% CI: 0.0005-0.0040).

Conclusion

Our study concludes that SII is positively correlated with the persistence of asthma yet has limited predictive power for asthma recurrence. This highlights SII's potential as a tool for assessing asthma risk and formulating targeted management strategies.

A single center retrospective study of systemic reactions' distribution and risk factors to subcutaneous immunotherapy with dust mite extract in patients with allergic rhinitis and/ or asthma

To analyze various risk factors including causes that may lead to adverse reactions, especially systemic adverse reactions（SRs）, before and after mite allergen subcutaneous immunotherapy (SCIT), so as to provide real-world reference data for further improving the safety of mite allergen SCIT. Methods: The local adverse reactions（LRs）and SRs of 230 patients with allergic rhinitis and/or asthma who received SCIT in Weifang people's hospital were analyzed retrospectively. The data of patient characteristics, drug factors and environmental elements of adverse reactions were collected and statistically analyzed. Results: There were 28 cases (12.2%) of SRs in 230 patients. All the patients received a total of 7515 injections and 37 SRs (0.49%) were observed. 32.4% (12/37) of SRs could identify their external and subjective triggers. SRs patients had higher 2-year SCIT compliance than no-SRs patients (p = 0.026). The prevalence of SRs in SCIT patients with atopic dermatitis or simple allergic asthma are no statistical significance (P = 0.111). Conclusion: the incidence of SRs in this study is within an ideal range. Through professional patient education and pre injection risk factor assessment, Compliance is still well-controlled and guaranteed although SRs occurred.

Blood eosinophil counts in the general population and airways disease: a comprehensive review and meta-analysis

BACKGROUND

The clinical context for using blood eosinophil (EOS) counts as treatment-response biomarkers in asthma and COPD requires better understanding of EOS distributions and ranges. We describe EOS distributions and ranges published in asthma, COPD, control (non-asthma/COPD) and general populations.

METHODS

We conducted a comprehensive literature review and meta-analysis of observational studies (January 2008 to November 2018) that included EOS counts in asthma, severe asthma, COPD, control and general populations. Excluded studies had total sample sizes <200, EOS as inclusion criterion, hospitalised population only and exclusively paediatric participants.

RESULTS

Overall, 91 eligible studies were identified, most had total-population-level data available: asthma (39 studies), severe asthma (12 studies), COPD (23 studies), control (seven studies) and general populations (14 studies); some articles reported data for multiple populations. Reported EOS distributions were right-skewed (seven studies). Reported median EOS counts ranged from 157-280 cells·µL-1 (asthma, 22 studies); 200-400 cells·µL-1 (severe asthma, eight studies); 150-183 cells·µL-1 (COPD, six studies); and 100-160 cells·µL-1 (controls, three studies); and 100-200 cells·µL-1 (general populations, six studies). The meta-analysis showed that observed variability was mostly between studies rather than within studies. Factors reportedly associated with higher blood EOS counts included current smoking, positive skin-prick test, elevated total IgE, comorbid allergic rhinitis, age ≤18 years, male sex, spirometric asthma/COPD diagnosis, metabolic syndrome and adiposity.

CONCLUSION

EOS distribution and range varied by study population, and were affected by clinical factors including age, smoking history and comorbidities, which, regardless of severity, should be considered during treatment decision-making.

Circulating white blood cells and lung function impairment: the observational studies and Mendelian randomization analysis

BACKGROUND

Circulating white blood cell (WBC) counts have been related to lung function impairment, but causal relationship was not established. We aimed to evaluate independent effects and causal relationships of WBC subtypes with lung function.

METHODS

The 19,159 participants from NHANES 2011-2012 (n = 3570), coke-oven workers (COW, n = 1762) and Dongfeng-Tongji (DFTJ, n = 13,827) cohorts were included in the observational studies. The associations between circulating counts of WBC subtypes and prebronchodilator lung function were evaluated by linear regression models and LASSO regression was used to select effective WBC subtypes. Summary statistics for WBC-associated SNPs were extracted from literature, and Mendelian randomization (MR) analysis with inverse-variance weighted (IVW) method was applied to estimate the causal effects of total WBC and subtypes on lung function among 4012 subjects from COW (n = 1126) and DFTJ cohorts (n = 2886).

RESULTS

Total WBC counts were negatively associated with lung function among three populations and their pooled analysis indicated that per 1 × 109 cells/L increase in total WBC was associated with 36.13 (95% CI: 30.35, 41.91) mL and 25.23 (95% CI: 19.97, 30.50) mL decrease in FVC and FEV1, respectively. Independent associations with lung function were found for neutrophils, monocytes, eosinophils and basophils (all p < .05), except lymphocytes. Besides, IVW MR analysis showed that genetically predicted total WBC and neutrophil counts were associated with reduced FVC (p = .017 and .021, respectively) and FEV1 (p = .048 and .043, respectively).

CONCLUSIONS

WBC subtypes were independently associated with lower lung function except lymphocytes. Our findings suggest that circulating neutrophils may be causal factors in lung function impairment.KEY MESSAGESWhite blood cell (WBC) subtypes were negatively associated with lung function level except lymphocytes in the observational studies.Associations of WBC subtypes with lung function may be modified by sex and smoking.Mendelian randomization analysis shows that neutrophils may be causal factors in lung function impairment.

Deep Learning Algorithms-Based CT Images in Glucocorticoid Therapy in Asthma Children with Small Airway Obstruction

CT image information data under deep learning algorithms was adopted to evaluate small airway function and analyze the clinical efficacy of different glucocorticoid administration ways in asthmatic children with small airway obstruction. The Res-NET in the deep learning algorithm was used to perform feature extraction, summary classification, and other reconstruction of CT images. A deep learning network model Mask-R-CNN was constructed to enhance the ability of image reconstruction. A total of 118 children hospitalized with acute exacerbation of asthma in the hospital were recruited. After acute exacerbation treatment, 96 children with asthma were screened out for small airway obstruction, which were divided into glucocorticoid aerosol inhalation group (group A, 32 cases), glucocorticoid combined with bronchodilator aerosol inhalation group (group B, 32 cases), and oral hormone therapy group (group C, 32 cases). Asthmatic children with small airway obstruction were screened after acute exacerbation treatment and were rolled into glucocorticoid aerosol inhalation group (group A), glucocorticoid combined with bronchodilators aerosol inhalation group (group B), and oral hormone therapy group (group C). Lung function indicators (maximal mid-expiratory flow (MMEF75 and 25), 50% forced expiratory flow (FEF50), and 75% forced expiratory flow (FEF75)), FeNO level, and airway inflammation indicators (IL-6, IL-35, and eosinophilic (EOS)) were compared before and one month after treatment. The ratio of airway wall thickness to outer diameter (T/D) and the percentage of airway wall area to total airway area (WA%) were measured by e-Health high-resolution CT (HRCT). The constructed network model was used to measure the patient's coronary artery plaque and blood vessel volume, and the image was reconstructed on the Res-Net network. It was found that the MSE value of the Res-Net network was the lowest, and the efficiency was very high during the training process. T/D and WA (%) of asthmatic children with small airway obstruction after treatment were significantly lower than those before treatment (P < 0.01). After treatment, MMEF75/25 and FEF75 were significantly higher than those before treatment (P < 0.05). Lung function-related indicator FEF50 was significantly higher than that before treatment (P < 0.01). FeNO level after treatment was remarkably lower than that before treatment (P < 0.01). In addition, lung function-related indicators, airway inflammation indicators, and FeNO level improved the most in group C, followed by group B, and those improvements in group A were the least obvious, with great differences among groups (P < 0.05). In summary, the Res-Net model proposed was of certain feasibility and effectiveness for CT image segmentation and can effectively improve the clinical evaluation of patient CT image information. Glucocorticoids could improve small airway function and airway inflammation in asthmatic children with small airway obstruction, and oral corticosteroids were more effective than aerosol inhalation therapy.

Role of systemic immune-inflammation index in asthma and NSAID-exacerbated respiratory disease

OBJECTIVE

Asthma is a heterogeneous disease characterized by chronic progressive airway inflammation. Although the disease has numerous phenotypes, there are no practical biomarkers for distinguishing the phenotypes from one another. To address this challenge, we aimed to reveal whether the systemic immune-inflammation index (SII), an important indicator of systemic inflammation and prognosis in various malignancies and vasculitis, can be used for distinguishing between asthma and NSAID-exacerbated respiratory disease (NERD).

METHODS

The study enrolled 105 patients (asthma: n = 69; NERD: n = 36). SII was calculated using the formula of neutrophil X platelet/lymphocyte number. Major risk factors, namely ACT score, eosinophil level, total IgE level, N-L ratio (NLR), P-L ratio (PLR), and SII, were evaluated by logistic regression analysis.

RESULTS

No significant differences were found between the clinical features of the two study groups. Patients with an SII value ≥895.6 had a probability of having NERD with a sensitivity of 30.56%, whereas those with a lower SII had a probability of having asthma with a sensitivity of 92.65%. In the logistic regression analysis, no risk factor was determined for identifying asthma or NERD. The N-L ratio was found to be the risk factor affecting categorized SII (OR = 264.2, 95% CI 9.9-7046.5, P = 0.001).

CONCLUSION

This is the first study to evaluate SII as a tool for differentiating asthma phenotypes. The presence of SII below the cutoff value can help exclude the diagnosis of NERD. There is a need for large-scale prospective studies to compare different phenotypes and determine the optimal cutoff value.

Anti-IL5 Therapies for Severe Eosinophilic Asthma: Literature Review and Practical Insights

Severe refractory asthma (SRA) still has a high economic and social impact, including a reduction in quality of life (QoL), productivity, a greater risk of exacerbations and emergency department (ED) visits. Another major issue is the need of oral corticosteroids (OCS), often due to a poor response to standard therapies or the lack of indication for currently available biological drugs. A thorough understanding of the immunological pathways and eosinophilopoietic processes allows a correct application of the new pharmacological strategies and leads to better clinical responses. For these unmet needs, several monoclonal antibody (mAb) drugs have been introduced over the past few years. These are mainly available for allergic and especially eosinophilic uncontrolled refractory asthma. As the number of therapeutic options increases, the choice of biological drugs can be made only after careful considerations of the particular asthma endotype, patients’ comorbidities and clinical data. The selection of the correct therapeutic option can therefore be guided after a careful evaluation of the particular endotype and phenotype, from the combined evaluation of inflammatory biomarkers, clinical picture and comorbidities. The careful evaluation of all these parameters can therefore help the physician in the optimal management of these complex patients, for whom it is often possible to achieve exceptional results by managing the available options in the best possible way. The aim of this review is to define the positioning of the biological drugs currently available for type 2 asthma, with a special focus on options for eosinophilic asthma in the context of the most recent knowledge of immunological pathways.