Acute bronchodilator responsiveness in subjects with and without airflow obstruction in five Latin American cities: The PLATINO study

Assessment of bronchodilator responsiveness to salbutamol or ipratropium using different criteria in treatment-naïve patients with asthma and COPD

Background

The criteria for significant bronchodilator responsiveness (BDR) were published in 2005 by the European Respiratory Society/American Thoracic Society, which were revised in 2021, however, data on the agreement between these two recommendations in untreated patients with airflow limitation are missing.

Aims

We aimed to study BDR to salbutamol (SABA) or ipratropium bromide (SAMA) in patients with suspected bronchial asthma or COPD at initial clinical presentation using the 2005 and 2021 criteria and explore clinical factors associated with BDR+.

Methods

Symptomatic, treatment-naïve patients with expiratory airflow limitation (n = 105, 57 men, age (mean ± standard deviation): 65 ± 10 years) underwent BDR testing with 400 mcg salbutamol (day 1) or 80 mcg ipratropium bromide (day 2) and BDR was measured after 15 and 30 minutes. Clinical factors with risk for BDR+ were assessed with binomial logistic regression analysis.

Results

We found a good agreement between the number of 2005-BDR+ and 2021-BDR+ patients at 15 and 30 minutes post-salbutamol and post-ipratropium (88.6-94.8%). More patients showed BDR+ after 30 minutes than following 15 minutes using either criterion. When results at 30 minutes are considered, the number of patients with 2005-BDR+ (82%) was higher than that of 2021-BDR+ (75%), with the proportion of SAMA+ patients being higher than that of SABA+ (2005: 70% vs. 49%, Fisher exact p < 0.01; 2021: 64% vs. 41%, p = 0.001). 2005-BDR+ and 2021-BDR+ to SABA were associated with decreasing pre-BD FEV1% predicted and the presence of cough. More patients with asthma were in the SABA+ group compared to the SAMA+ group (2005: 71% vs. 53%, Fischer exact p = 0.04; 2021: 77% vs. 52%, p = 0.02).

Conclusions

Fewer patients show BDR+ according to the 2021 criteria in comparison with the 2005 recommendations, and protocols for BDR testing may consider the assessment of response to both SABA and SAMA after 30 minutes.

GSTP1 rs4147581 C>G and NLRP3 rs3806265 T>C as Risk Factors for Chronic Obstructive Pulmonary Disease: A Case-Control Study

Background

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory ailment influenced by a blend of genetic and environmental factors. Inflammatory response and an imbalance in oxidative-antioxidant mechanisms constitute the primary pathogenesis of COPD. Glutathione S-transferase P1(GSTP1) plays a pivotal role as an antioxidant enzyme in regulating oxidative-antioxidant responses in the pulmonary system. The activation of the NOD-like receptor thermal protein domain (NLRP3) inflammatory vesicle can trigger an inflammatory response. Several investigations have implicated GSTP1 and NLRP3 in the progression of COPD; nonetheless, there remains debate regarding this mechanism.

Methods

Employing a case-control study design, 312 individuals diagnosed with COPD and 314 healthy controls were recruited from Gansu Province to evaluate the correlation between GSTP1 (rs4147581C>G and rs1695A>G) and NLRP3 (rs3806265T>C and rs10754558G>C) polymorphisms and the susceptibility to COPD.

Results

The presence of the GSTP1 rs4147581G allele substantially elevated the susceptibility to COPD (CGvs.CC:OR=3.11,95% CI=1.961-4.935, P<0.001;GGvs.CC:OR=2.065,95% CI=1.273-3.350, P=0.003; CG+GGvs.CC:OR=2.594,95% CI=1.718-3.916, P<0.001). Similarly, the NLRP3rs3806265T allele significantly increased the susceptibility to COPD (TC:TT:OR=0.432,95% CI=0.296-0.630; TC+CCvs.TT:OR=2.132,95% CI=1.479-3.074, P<0.001). However, no statistically significant association was discerned between the rs1695A>G and rs10754558G>C polymorphisms and COPD susceptibility (P>0.05).

Conclusion

In summary, this study ascertained that the GSTP1 rs4147581C>G polymorphism is associated with increased COPD susceptibility, with the G allele elevating the risk of COPD. Similarly, the NLRP3 rs3806265T>C polymorphism is linked to elevated COPD susceptibility, with the T allele heightening the risk of COPD.

Relation between partial arterial carbon dioxide pressure and pH value and optic nerve sheath diameter: a prospective self-controlled non-randomized trial study

OBJECTIVE

This study aims to determine if there is a correlation between differences in optic nerve sheath diameter (ONSD) and changes in PaCO2 and pH values that were measured in the arterial blood gas (ABG) before and after treatment in COPD patients with acute hypercarbic respiratory failure (AHRF).

MATERIALS AND METHODS

This study serves as a prospective self-controlled non-randomized trial study conducted in the emergency clinic of a tertiary hospital. Forty-four patients with COPD, who were found to have acidosis and hypercarbia in ABG and had an indication for non-invasive mechanic ventilation (NIMV), were analyzed prospectively. Demographic information, vital findings, initial ABG values, the ONSD measurement (before the NIMV treatment), consciousness state, and the ABG results obtained in the second hour of the monitoring and the ONSD measurement (after the NIMV treatment) were recorded.

RESULTS

In this study, 13 (29.5%) of the patients were female and 31 (70.5%) were male. The age distribution was evaluated as 68.3 ± 9.2 years; the minimum age was 54 and the maximum was 91. A high level of positively significant correlation was found between the mean ONSD and PaCO2 (p < 0.0001). There is a high fit (0.72) between the mean ONSD and PaCO2. A moderate level of negatively significant correlation was found between the mean ONSD and the pH (p < 0.0001). However, there is an insignificant low fit (0.32) between the mean ONSD and the pH.

CONCLUSION

The ONSD changed significantly and in a highly correlated manner to acute changes in PaCO2 levels.

The Effectiveness of Traditional Chinese Medicine (TCM) as an Adjunct Treatment on Stable COPD Patients: A Systematic Review and Meta-Analysis

Background

Traditional Chinese medicine (TCM), including Chinese herbal medicine (CHM) and acupuncture, exhibits beneficial effects on stable chronic obstructive pulmonary disease (COPD) such as improving lung function and reducing exacerbation. Previous research studies have examined either CHM or acupuncture alone, which are not the usual practice in TCM clinic setting. We conduct a systematic review for evaluating the clinical effectiveness and safety of TCM by combining CHM and acupuncture.

Methods

Databases are searched from inception to November 2019. Randomized controlled trials examining either acupuncture or CHM on stable COPD are included. Primary outcomes include lung functions, exacerbations, and COPD assessment test. Secondary outcomes include quality of life, TCM syndrome score and effective rate, and 6-minute walk distance. Two independent reviewers extract data and assess the quality of evidence and generate meta-analysis and risk of bias by STATA. This protocol follows the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines.

Results

100 randomized controlled trials (8291 participants) were included to compare add-on Chinese medicine treatment with conventional treatment (CT). Combining CHM with CT improves FEV₁ (MD: 0.18, 95% CI: 0.08, 0.28), exacerbation rate (MD: −0.29, 95% CI: −0.61, 0.03), COPD assessment test (MD: −2.16, 95% CI: −3.44, -0.88), TCM syndrome score (MD: −3.96, 95% CI: −5.41, −2.51) and effective rate (RR: 0.89, 95% CI: 0.80, 0.93), and 6-minute walk test (MD: 37.81, 95% CI: 20.90, 54.73). No serious adverse events were reported. Risk of bias: low to unclear.

Conclusions

This review identifies sufficient moderate-to-low-quality evidence to suggest TCM as an adjunct treatment for stable COPD patients. Though heterogeneity was low among studies, the results were limited and the quality of evidence was low or very low based on small sample sizes and risk of bias. Future studies with larger sample sizes are warranted. The trial is registered with CRD42019161324.

Protein succination as a potential surrogate biomarker of airway obstruction. The ilervas project

BACKGROUND

Airway obstruction (AO) is associated with hypoxemia, systemic inflammation and oxidative stress. These conditions can favor the formation of Advanced Glycation End-products (AGEs) and induce mitochondrial stress. The latter can alter metabolite intermediates in the Krebs cycle leading to the formation of the cysteine-fumarate adduct S-(2-succino) cysteine (2SC) in proteins (protein succination). Protein succination has not been described in airways diseases.

RESEARCH QUESTION

To assess differences in levels of AGEs and 2SC between patients with AO and normal spirometry.

STUDY DESIGN

and Methods: In this case-control study, we investigated 35 moderate to severe AO patients and 31 subjects with normal spirometry, matched for age, gender, body mass index (BMI), tobacco history, prediabetes and adherence to Mediterranean diet. Plasma 2SC and AGEs concentrations were measured by GS/MS, and AGEs in skin were determined measuring autofluorescence (SAF). Multivariate logistic regression models explored the association between AGEs in the skin, 2SC and the presence of AO.

RESULTS

The population was predominantly middle-age (mean of 58.7 years-old), overweight (median of BMI 26.7 kg/m²) and male subjects (69.7%). Patients with AO showed higher values of SAF (p = 0.04) and 2SC (p = 0.047). No differences were observed for plasma AGEs. SAF and 2SC were significantly associated with the presence of AO after adjusting for age, gender, smoking history, BMI and Mediterranean diet score (p = 0.041 and p = 0.038, respectively).

INTERPRETATION

Skin AGEs and 2SC are increased in patients with moderate to severe AO and independently associated with its presence. Further studies should confirm these findings and explore their potential role as a biomarker for the disease.

Exploring the Impact of Lung Cancer Screening on Lung Cancer Mortality of Smokers With Obstructive Lung Disease: Analysis of the NLST-ACRIN Cohort

BACKGROUND

Lung Cancer (LC) screening with low dose chest computed tomography (LDCT) in smokers reduces LC mortality. Patients with Obstructive Lung Disease (OLD) are at high risk for LC. The potential effect of LC screening in this population is unknown.

OBJECTIVE

To determine if screening with LDCT reduces LC mortality in smokers with spirometrically defined OLD.

METHODS

The National Lung Screening Trial-American College of Radiology Imaging Network (NLST-ACRIN) study included 13,831 subjects (55-74 years of age with ≥30 pack-year history of smoking) that had a baseline spirometry. Randomly assigned to LDCT or Chest X-ray, all had 3 annual rounds of screening. LC mortality was compared between the LDCT and chest X-ray arms during the 1st year and at 6 years of follow up. Landmark analysis explored LC mortality differences between arms after the first year.

RESULTS

From the 4584 subjects with OLD (FEV1/FVC <0.7), 152 (3.3%) died from LC. Multivariable analysis showed that screening trended to decrease LC mortality at 6 years (HR, 95%CI: 0.75, 0.55-1.04, p=0.09). During the 1st year no differences were found between arms (p=0.65). However, after this year, LDCT significantly decreased LC mortality (HR, 95%CI: 0.63, 0.44-0.91, p=0.01). The number needed to screen to avoid one LC death in these subjects was 108 while in those without OLD was 218.

CONCLUSIONS

LC screening with LDCT in smokers with spirometrically diagnosed OLD, showed a trend to reduce lung cancer mortality but a study with a larger number of patients and with a more robust design would be needed to confirm these findings.

Diagnostic Accuracy of Bronchodilator Response for Asthma in a Population of South China

INTRODUCTION

A significant bronchodilator response is commonly defined as a 12% or greater and 200 ml or greater change in FEV₁ from baseline according to the 2005 American Thoracic Society (ATS)/European Respiratory Society (ERS) criterion. A number of studies have shown that the ATS/ERS criterion has limitations in asthma diagnosis, and some experts have argued for correcting the criteria. The aim of this study is to investigate the diagnostic value of acute bronchodilator response for asthma in a Southern Chinese population.

METHODS

We prospectively evaluated 805 patients with obstructive lung disease (309 for asthma, 496 for non-asthma). Spirometry was performed according to the ATS/ERS guidelines. Data were analyzed by SPSS 18.0. The receiver-operating characteristic (ROC) curve was drawn to assess the diagnostic accuracy of the ATS/ERS criterion based on FEV₁. Linear regression was used to analyze the factors of FEV₁ change.

RESULTS

The sensitivity and specificity of the acute bronchodilator test when judged by the ATS/ERS criteria (200 ml or higher and 12% improvement) were 68.6% and 78.2%, respectively. For the ATS/ERS criteria, the Youden Index, which comprehensively reflects the authenticity of a diagnostic test, was 46.8%. The absolute change of FEV₁ positively correlated with baseline FEV₁ and weight and negatively with age, while the percentage change of FEV₁ was negatively correlated with baseline FEV₁, age and height and positively with weight. Compared with the different diagnostic values, when ∆FEV₁ was 195 ml and ∆FEV_1i% was 14%, the Youden Index was the largest (48.2%) and the diagnostic capability of the test the biggest.

CONCLUSIONS

The ATS/ERS criterion for acute bronchodilator response might not be completely suitable for asthma in the Chinese population.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (Registry ID: ChiCTR-DDT-14004976).

FUNDING

This work was supported by the National Natural Science Foundation of China (grant nos. 81670027, 81270080).

Pre- and post-bronchodilator airway obstruction are associated with similar clinical characteristics but different prognosis - report from a population-based study

Introduction

According to guidelines, the diagnosis of COPD should be confirmed by post-bronchodilator (post-BD) airway obstruction on spirometry; however, in clinical practice, this is not always performed. The aim of this population-based study was to compare clinical characteristics and prognosis, assessed as mortality, between subjects with airway obstruction divided into pre- but not post-BD obstruction, post-BD airway obstruction (COPD), and subjects without airway obstruction.

Materials and methods

In 2002–2004, four adult population-based cohorts were reexamined with spirometry and structured interview. Subjects with airway obstruction, with a ratio of forced expiratory volume in 1 s to (forced) vital capacity <0.70 (n=993), were identified together with sex- and age-matched referents (n=993). These subjects were further divided into subjects with pre- but not post-BD airway obstruction (pre- not post-BD obstruction) and subjects with post-BD airway obstruction (COPD). Mortality data were collected until December 31, 2014.

Results

Out of 993 subjects with airway obstruction, 736 (74%) had COPD and 257 (26%) pre- not post-BD obstruction. Any respiratory symptoms, allergic rhinitis, asthma, exacerbations, and comorbidities were equally common among subjects with COPD and pre- not post-BD obstruction, but less common among nonobstructive subjects. Mortality was highest among subjects with COPD and higher in men than in women. In both sexes, COPD, but not pre- not post-BD obstruction, was associated with an increased risk for death compared to those without airway obstruction. When COPD was divided into Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages, GOLD 2 and 3–4 had an increased risk for death when compared to the nonobstructive group, also when adjusted for common confounders and comorbidities such as heart disease, diabetes, and anxiety/depression.

Conclusion

Even though subjects with COPD and pre- not post-BD obstruction had fairly similar presentation of clinical characteristics, only those with COPD, specifically GOLD stage ≥2, had increased risk for death when compared with nonobstructive subjects.

Bronchodilator reversibility in patients with COPD revisited: short-term reproducibility

Categorization of patients with COPD as reversible or nonreversible to a bronchodilator may change over time. This post hoc analysis aimed to determine if an individual's reversibility, when treated as a continuous variable, could predict his/her future response to two short-acting bronchodilators: albuterol and ipratropium. The analysis was completed using data from a 4-week, randomized, open-label, two-period crossover study (NCT01691482; GSK study DB2114956). Patients received albuterol (doses: UK =4×100 μg/puff; US =4×90 μg/puff) followed 1 hour later by ipratropium (4×20 μg/puff) or vice versa during treatment Period 1. The order of treatments was reversed during Period 2. Predefined efficacy end points included pre- and post-bronchodilator forced expiratory volume in 1 second. The correlation coefficient between bronchodilator response on Days 1 and 10 was investigated, as well as the correlation between treatment response on Day 1 and the mean treatment response on Days 5-10, for each individual patient. Bronchodilator response to albuterol on Day 1 was strongly correlated with that on Day 10 (r=0.64; n=53). The correlation coefficient of bronchodilator treatment response on Day 1 and Days 5-10 was 0.78 (P<0.001; n=53) and 0.76 (P<0.001; n=54) for albuterol and ipratropium, respectively. A single measurement of the initial bronchodilator response to albuterol or ipratropium was, therefore, highly correlated with the subsequent mean bronchodilator response over 5-10 days, demonstrating its potential usefulness for future treatment decisions.

Development of a simple screening tool for opportunistic COPD case finding in primary care in Latin America: The PUMA study

BACKGROUND AND OBJECTIVE

Opportunistic chronic obstructive pulmonary disease (COPD) case finding approaches for high-risk individuals with or without symptoms is a feasible option for disease identification. PUMA is an opportunistic case finding study conducted in primary care setting of Argentina, Colombia, Venezuela and Uruguay. The objectives were to measure COPD prevalence in an at-risk population visiting primary care for any reason, to assess the yield of this opportunistic approach and the accuracy of a score developed to detect COPD.

METHODS

Subjects attending routine primary care visits, ≥40 years of age, current or former smokers or exposed to biomass smoke, completed a questionnaire and performed spirometry. COPD was defined as post-bronchodilator (post-BD) forced expiratory volume in 1 s (FEV1 )/forced vital capacity (FVC) < 0.70 and the lower limit of normal of FEV1 /FVC.

RESULTS

A total of 1743 subjects completed the interview; 1540 performed acceptable spirometry. COPD prevalence was 20.1% (n = 309; ranging from 11.0% in Venezuela to 29.6% in Argentina) when defined using post-BD FEV1 /FVC < 0.70, and 14.7% (n = 226; ranging from 8.3% in Venezuela to 21.8% in Colombia) using the lower limit of normal. Logistic regression analysis for both definitions showed that the risk of COPD was significantly higher for persons >50 years, heavy smokers (>30 pack-years), with dyspnoea, and having prior spirometry. A simple score and a weighted score constructed using the following predictive factors: gender, age, pack-years smoking, dyspnoea, sputum, cough and spirometry, had a mean accuracy for detecting COPD (post-BD FEV1 /FVC < 0.70) of 76% and 79% for the simple and weighted scores, respectively.

CONCLUSION

This simple seven-item score is an accurate screening tool to select subjects for spirometry in primary care.

Modest genetic influence on bronchodilator response: a study in healthy twins

Aim

To determine the reasons for large standard deviation of bronchodilator response (BDR) and establish whether there is a potential heritable component in healthy subjects.

Methods

67 monozygotic and 42 dizygotic adult twin pairs were assessed for bronchodilator response (%change in FEV₁ after inhaling 400 µg salbutamol). Univariate quantitative genetic modeling was performed.

Results

Multiple regression modeling showed a significant association between BDR and sex and baseline FEV1 (P < 0.05), while no association was found with smoking habits, body mass index, or age. Within pair correlation in monozygotic twins was modest (0.332), but higher than in dizygotic twins (0.258). Age-, sex-, and baseline FEV1-adjusted genetic effect accounted for 14.9% (95% confidence interval, CI 0%-53.1%) of the variance of BDR, shared environmental effect for 18.4% (95% CI 0%-46.8%), and unshared environmental effect for 66.8% (95% CI 46.8%-88.7%).

Conclusion

Our twin study showed that individual differences in BDR can be mostly explained by unshared environmental effects. In addition, it is the first study to show low, insignificant hereditary influences, independently from sex, age, and baseline FEV1.