The rapid FEV(1) decline in chronic obstructive pulmonary disease is associated with predominant emphysema: a longitudinal study

Short- and long-term outcomes of pulmonary emphysema patients on mechanical ventilation admitted to the intensive care unit for acute respiratory failure: A retrospective observational study

INTRODUCTION

Acute respiratory failure is a leading cause of admission to the intensive care unit (ICU), with mortality rates remaining stagnant despite advances in resuscitation techniques. Comorbidities, notably chronic obstructive pulmonary disease, significantly impact ICU patient outcomes. Pulmonary emphysema, commonly associated with chronic obstructive pulmonary disease, poses a significant risk, yet its influence on ICU mortality remains understudied.

OBJECTIVES

The aim of this study was to assess the short- and long-term outcomes of ICU patients with pulmonary emphysema requiring mechanical ventilation for acute respiratory failure, evaluating the impact of emphysema severity.

METHODS

A single-centre retrospective cohort study was conducted from 2015 to 2021. Patients with pulmonary emphysema requiring invasive ventilation were included. Emphysema severity was assessed using chest computed tomography scans. Data on mortality, length of stay, and ventilator-free days were collected. Statistical analyses were performed to identify factors associated with outcomes.

RESULTS

Of the 89 included patients, 31.5% died during their ICU stay, with a 39.3% mortality within 12 months postdischarge. Emphysema severity did not significantly correlate with mortality or ventilator-free days. Chronic heart failure emerged as a significant predictor of ICU and in-hospital mortality.

CONCLUSIONS

Emphysema severity does not appear to independently affect mortality in intubated ICU patients with acute respiratory failure. However, mortality rates remain high, warranting further investigation into contributing factors. Our findings underline the complexity of managing critically ill patients with pulmonary emphysema and emphasise the need for comprehensive patient assessment and personalised treatment approaches.

Implications of Global Lung Function Initiative Spirometry Reference Equations in Northeast Asian Patients With COPD

BACKGROUND

Accurate spirometry interpretation is critical in the diagnosis and management of COPD. With increasing efforts for a unified approach by the Global Lung Function Initiative (GLI), this study evaluated the application of race-specific 2012 GLI and race-neutral 2022 GLI reference equations compared with Choi's reference equations, which are derived and widely used in South Korea, for spirometry interpretation in Northeast Asian patients with COPD.

RESEARCH QUESTION

What are the effects of applying race-specific 2012 GLI, race-neutral 2022 GLI, and Choi's reference equations on the diagnosis, severity grade, and clinical outcome associations of COPD?

STUDY DESIGN AND METHODS

Serial spirometry data from the Korea COPD Subgroup Study (KOCOSS) consisting of 3,477 patients were used for reanalysis using 2012 GLI, 2022 GLI, and Choi's reference equations. The COPD diagnosis and severity categorization, associations with disease manifestations and health outcomes, and longitudinal trajectories of lung function were determined.

RESULTS

Although there was strong concordance in COPD diagnosis comparing 2012 GLI, and 2022 GLI reference equations with Choi's reference equations, a notable portion of patients were reclassified to milder disease severity (17.0% and 23.4% for 2012 GLI and 2022 GLI reference equations, respectively). Relationships between FEV1 % predicted values calculated using 2012 GLI, 2022 GLI, and Choi's equations with clinical outcomes including dyspnea severity, exercise capacity, health-related quality of life, and frequency of exacerbations remain consistently significant. Similar annual decline rates of FEV1 and FVC % predicted were observed among the reference equations used, except for slower annual decline rate of FEV1 in Choi's equation compared with 2022 GLI race-neutral equation.

INTERPRETATION

Application of GLI reference equations for spirometry interpretation in Northeast Asian patients with COPD has potential implications on disease severity grade for clinical management and trial participation, and maintains consistent significant relationships with key disease outcomes.

Different Transcriptome Features of Peripheral Blood Mononuclear Cells in Non-Emphysematous Chronic Obstructive Pulmonary Disease

Non-emphysematous chronic obstructive pulmonary disease (COPD), which is defined based on chest computed tomography findings, presented different transcriptome features of peripheral blood mononuclear cells (PBMCs) compared with emphysematous COPD. Enrichment analysis of transcriptomic data in COPD demonstrated that the "Hematopoietic cell lineage" pathway in Kyoto Encyclopedia of Genes and Genomes pathway analysis was highly upregulated, suggesting that cellular dynamic dysregulation in COPD lungs is affected by pathologically modified PBMCs. The differentially expressed genes (DEGs) upregulated in PBMCs reflected the disease state of non-emphysematous COPD. Upregulated DEGs such as XCL1, PRKCZ, TMEM102, CD200R1, and AQP1 activate T lymphocytes and eosinophils. Upregulating keratan sulfate biosynthesis and metabolic processes is associated with protection against the destruction of the distal airways. ITGA3 upregulation augments interactions with extracellular matrix proteins, and COL6A1 augments the profibrotic mast cell phenotype during alveolar collagen VI deposition. Upregulating HSPG2, PDGFRB, and PAK4 contributes to the thickening of the airway wall, and upregulating SERPINF1 expression explains the better-preserved vascular bed. Therefore, gene expression and pathway analysis in PBMCs in patients with non-emphysematous COPD represented type 2 immune responses and airway remodeling features. Therefore, these patients have asthmatic potential despite no clinical signs of asthma, in contrast to those with emphysematous COPD.

Investigation of time profile of FEV1 across the onset of potential COPD: a retrospective cohort study using medical checkup data in Japan

This study compared the time profile of FEV₁ after COPD diagnosis among rapid decliners, slow decliners, and sustainers in the year of COPD diagnosis. COPD subjects were identified from the annual medical checkup records of Hitachi, Ltd., employees in Japan (April 1998-March 2019). Subjects were categorized into 3 groups (rapid decliner [decrease of FEV₁ ≥ 63 mL/year], slow decliner [< 63 and ≥ 31 mL/year], and sustainer [< 31 mL/year]) for 5 years. The time profile of FEV₁ was compared using mixed-effects model for 5 years after diagnosis; risk factors of rapid decliner were detected using logistic model/gradient boosting decision tree. Of 1294 eligible subjects, 18.6%, 25.7%, and 55.7% were classified as rapid decliners, slow decliners, and sustainers, respectively. The annual rates of FEV₁ decline were similar 3 years before and until COPD diagnosis. The mean FEV₁ in rapid decliners was 2.82 ± 0.04 L in year 0 and 2.41 ± 0.05 L in year 5, and in sustainers, it was 2.67 ± 0.02 L and 2.72 ± 0.02 L (year 0, p = 0.0004). In conclusion, FEV₁ declined yearly before diagnosis and the time profiles of FEV₁ were different in the 3 groups after COPD diagnosis. Therefore, appropriate treatment of the 3 groups with regular lung function tests is necessary to follow FEV₁ decline after COPD onset.

Emphysema-Predominant COPD Had a Greater 5-Year Mortality and a Worse Annual Decline in Lung Function Than Airway Obstruction-Predominant COPD or Asthma at Initial Same Degree of Airflow Obstruction

Background and Objectives: We studied whether the extent of exertional oxygen desaturation and emphysema could cause greater mortality in COPD and asthma independent of airflow obstruction. Materials and Methods: We performed a 5-year longitudinal observational study in COPD and asthma patients who matched for airflow obstruction severity. All subjects performed a 6-min walk test (6MWT) and high-resolution computed tomography (HRCT) and followed spirometry and oxygen saturation (SpO2) during the 6MWT every 3-6 months. Overall survival was recorded. Cumulative survival curves were performed according to the Kaplan-Meier method and compared with the log-rank test. Results: The COPD group had higher emphysema scores, higher Δinspiratory capacities (ICs) and lower SpO2 during the 6MWT, which showed a greater yearly decline in FEV1 (40.6 mL) and forced vital capacity (FVC) (28 mL) than the asthma group (FEV1, 9.6 mL; FVC, 1.2 mL; p < 0.05). The emphysema-predominant COPD group had an accelerated annual decline in lung function and worse survival. The nadir SpO2 ≤ 80% and a higher emphysema score were the strong risk factors for mortality in COPD patients. Conclusions: The greater structural changes with a higher emphysema score and greater desaturation during the 6MWT in COPD may contribute to worse yearly decline in FEV1 and higher five-year mortality than in asthma patients with a similar airflow obstruction. The lowest SpO2 ≤ 80% during the 6MWT and emphysema-predominant COPD were the strong independent factors for mortality in chronic obstructive airway disease patients.

Low FVC/TLC in Preserved Ratio Impaired Spirometry (PRISm) is associated with features of and progression to obstructive lung disease

One quarter of individuals with Preserved Ratio Impaired Spirometry (PRISm) will develop airflow obstruction, but there are no established methods to identify these individuals. We examined the utility of FVC/TLC in identifying features of obstructive lung disease. The ratio of post-bronchodilator FVC and TLC_CT from chest CT (FVC/TLC_CT) among current and former smokers with PRISm (FEV₁/FVC ≥ 0.7 and FEV1 < 80%) in COPDGene was used to stratify subjects into quartiles: very high, high, low, and very low. We examined the associations between FVC/TLC_CT quartiles and (1) baseline characteristics, (2) respiratory exacerbations, (3) progression to COPD at 5 years, and (4) all-cause mortality. Among participants with PRISm at baseline (n = 1,131), the very low FVC/TLC_CT quartile was associated with increased gas trapping and emphysema, and higher rates of progression to COPD at 5 years (36% versus 17%; p < 0.001) relative to the very high quartile. The very low FVC/TLC_CT quartile was associated with increased total (IRR = 1.65; 95% CI [1.07–2.54]) and severe (IRR = 2.24; 95% CI [1.29–3.89]) respiratory exacerbations. Mortality was lower in the very high FVC/TLC_CT quartile relative to the other quartiles combined. Reduced FVC/TLC_CT ratio in PRISm is associated with increased symptoms, radiographic emphysema and gas trapping, exacerbations, and progression to COPD.

Genetic landscape of chronic obstructive pulmonary disease identifies heterogeneous cell-type and phenotype associations

Chronic obstructive pulmonary disease (COPD) is the leading cause of respiratory mortality worldwide. Genetic risk loci provide new insights into disease pathogenesis. We performed a genome-wide association study in 35,735 cases and 222,076 controls from the UK Biobank and additional studies from the International COPD Genetics Consortium. We identified 82 loci associated with P < 5 × 10-8; 47 of these were previously described in association with either COPD or population-based measures of lung function. Of the remaining 35 new loci, 13 were associated with lung function in 79,055 individuals from the SpiroMeta consortium. Using gene expression and regulation data, we identified functional enrichment of COPD risk loci in lung tissue, smooth muscle, and several lung cell types. We found 14 COPD loci shared with either asthma or pulmonary fibrosis. COPD genetic risk loci clustered into groups based on associations with quantitative imaging features and comorbidities. Our analyses provide further support for the genetic susceptibility and heterogeneity of COPD.

Associations between respiratory health and ambient air quality in Canakkale, Turkey: a long-term cohort study

Few epidemiological studies investigating the association between air pollution and health are available in Turkey. The aim of this cohort-type study is to examine the relationships between ambient air quality, respiratory diseases, and decreases in pulmonary function over a year in three different towns in Canakkale: Canakkale Central town (region I), Lapseki town center (region II), and Can town (region III). Region III had four different sub-regions, which were Can town center (region III-A), and the villages located around Can town, namely Durali (region III-B), Kulfal (region III-C), and Yuvalar (region III-D). In the first stage of the study, a detailed questionnaire was completed by the participants (n = 1152) in face-to-face interviews and pulmonary function test (PFT) was performed. In the second stage of the study, PFT measurements were repeated 1 year after the first stage. Particulate matter, SO₂, NO₂, and ozone were gathered from air quality monitoring stations located in the centers of the three regions. The most polluted area was region III, while region I and region II were the least polluted areas. The risk of pulmonary function decline throughout a year was 2.1 times higher in region III, 2.4 times higher both in regions III-B and III-C, and 1.6 times higher for smokers in all regions. In the present study, ambient air quality was worse in region III (industrialized region), which influenced PFT scores and the prognostics for chronic respiratory diseases. The findings of this study should be considered for future investment plans in this region related to human and environmental health needs.

Phenotyping Before Starting Treatment in COPD?

Chronic Obstructive Pulmonary Disease (COPD) is a heterogeneous and complex disease with great morbidity and mortality. Despite the new developments in the managements of COPD, it was recognized that not all patients benefit from the available medications. Therefore, efforts to identify subgroups or phenotypes had been made in order to predict who will respond to a class of drugs for COPD. This review will discuss phenotypes, endotypes, and subgroups such as the frequent exacerbator, the one with systemic inflammation, the fast decliner, ACOS, and the one with co-morbidities and their impact on therapy. It became apparent, that the "inflammatory" phenotypes: frequent exacerbator, chronic bronchitic, and those with a number of co-morbidities need inhaled corticosteroids; in contrast, the emphysematous type with dyspnea and lung hyperinflation, the fast decliner, need dual bronchodilation (deflators). However, larger, well designed studies clustering COPD patients are needed, in order to identify the important subgroups and thus, to lead to personalize management in COPD.

A study of chronic obstructive pulmonary disease-specific causes of osteoporosis with emphasis on the emphysema phenotype

BACKGROUND

Osteoporosis, the most common extra-pulmonary complication of chronic obstructive pulmonary disease (COPD), may be related to general causes or COPD-specific causes such as low forced expiratory volume in 1 s (FEV1) and hypoxia. A few studies reported that emphysema is an independent risk factor for osteoporosis. However, other workers considered the association to be confounded by low FEV1 and low body mass index (BMI) which cluster with emphysema.

AIMS

To study the association between osteoporosis and emphysema in a model that includes these potentially confounding factors.

METHODS

We studied prospectively 52 COPD patients with both high resolution computed tomography and carbon monoxide diffusion coefficient as diagnostic markers of emphysema. Dual-energy X-ray absorptiometry was used to measure the bone mass density (BMD) of lumbar vertebrae and neck of the femur. Vertebral fractures were evaluated using the Genant semiquantitative score. Multiple linear regression analysis was used to identify the following independent variables: age, BMI, FEV1% predicted, PaO2, emphysema score, C-reactive protein (CRP), and dyspnea score as related to BMD. P ≤ 0.05 was considered statistically significant.

RESULTS

There was no significant difference in the serum Vitamin D levels, vertebral fracture score, or BMD between the emphysematous and nonemphysematous patients. Multivariate analysis showed that (in a model including age, BMI, FEV1, PaO2, emphysema score, CRP, and dyspnea score) only reduced BMI, FEV1, and PaO2 were independent risk factors for low BMD.

CONCLUSIONS

The emphysematous phenotype is not a risk factor for osteoporosis independently of BMI, FEV1, and PaO2.

Can computed tomography and carbon monoxide transfer coefficient diagnose an asthma-like phenotype in COPD?

BACKGROUND AND OBJECTIVE

Post-mortem and computed tomography (CT) studies indicated that emphysema is a feature of COPD even in the 'blue bloater/chronic bronchitis' type. We aim to test the hypothesis that the non-emphysematous patients are distinct from the main body of COPD and are more akin to asthmatic patients.

METHODS

We studied 54 patients with COPD. Emphysema was measured by Goddard's visual scoring of CT scan and the carbon monoxide transfer coefficient (KCO). Bronchial biopsy was offered for thickness of basement membrane (BM) (≥7 µm) as a marker of remodelling in irreversible asthma. Spirometry was repeated after therapy with Budesonide/Formoterol for 1 year.

RESULTS

The non-emphysematous phenotype were 24 of 54 patients (44%) by CT scan and 23 of 54 patients (43%) by KCO, showing agreement in 53 out of 54 patients. The non-emphysematous patients were younger, had higher forced expiratory volume in 1 s (FEV₁ ) (median 61% vs 49.7%), greater prevalence of hypertrophy of nasal turbinates and higher serum IgE. The emphysematous phenotype had lower BMI and greater dyspnoea score. The BM was thickened in 11 of 14 and 0 of 10 patients in the non-emphysematous and emphysematous groups, respectively. Three patients without emphysema and a normal BM normalized their FEV₁ upon receiving inhaled corticosteroid (ICS)/long-acting β2 agonist (LABA). All the non-emphysematous improved their FEV₁ after ICS/LABA (median = 215 mL). The median decline in the emphysematous was -65 mL.

CONCLUSION

The non-emphysematous phenotype of COPD displays important features of asthma: clinical picture, histology and response to ICS. CT and KCO can predict spirometric response to ICS/LABA.

Evaluation of Individuals at Risk for COPD: Beyond the Scope of the Global Initiative for Chronic Obstructive Lung Disease

The Global initiative for chronic Obstructive Lung Disease (GOLD) Strategy is a valuable tool for clinicians in the diagnosis and management of patients with established chronic obstructive pulmonary disease (COPD). However, there are no recommendations for the evaluation of individuals, exposed to risk factors, who are most likely to develop COPD. Consequently, it is necessary to consider all of the factors that may play a role in the pathogenesis of COPD: genetic factors, gender, socioeconomic status, disadvantageous factors in childhood, lung diseases and exposure to risk factors such as smoking, biomass fuel smoke, occupational hazards and air pollution. Along with the clinical assessment, periodic spirometry should be performed to evaluate lung function and make possible early detection of individuals who will develop the disease through the rate of forced expiratory volume in 1 second (FEV₁) decline. The first spirometry, periodicity, and clinically significant decline in FEV₁ will encompass the cornerstones of clinical follow up. This approach allows the implementation of important interventions in order to help individuals to cease contact with risk factors and prevent progressive respiratory impairment with the consequent deterioration of quality of life and increased morbidity and mortality.

Prediction of Long-Term Benefits of Inhaled Steroids by Phenotypic Markers in Moderate-to-Severe COPD: A Randomized Controlled Trial

BACKGROUND

The decline in lung function can be reduced by long-term inhaled corticosteroid (ICS) treatment in subsets of patients with chronic obstructive pulmonary disease (COPD). We aimed to identify which clinical, physiological and non-invasive inflammatory characteristics predict the benefits of ICS on lung function decline in COPD.

METHODS

Analysis was performed in 50 steroid-naive compliant patients with moderate to severe COPD (postbronchodilator forced expiratory volume in one second (FEV1), 30-80% of predicted, compatible with GOLD stages II-III), age 45-75 years, >10 packyears smoking and without asthma. Patients were treated with fluticasone propionate (500 μg bid) or placebo for 2.5 years. Postbronchodilator FEV1, dyspnea and health status were measured every 3 months; lung volumes, airway hyperresponsiveness (PC20), and induced sputum at 0, 6 and 30 months. A linear mixed effect model was used for analysis of this hypothesis generating study.

RESULTS

Significant predictors of attenuated FEV1-decline by fluticasone treatment compared to placebo were: fewer packyears smoking, preserved diffusion capacity, limited hyperinflation and lower inflammatory cell counts in induced sputum (p<0.04).

CONCLUSIONS

Long-term benefits of ICS on lung function decline in patients with moderate-to-severe COPD are most pronounced in patients with fewer packyears, and less severe emphysema and inflammation. These data generate novel hypotheses on phenotype-driven therapy in COPD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00158847.

Effect of tiotropium on lung function decline in early-stage of chronic obstructive pulmonary disease patients: propensity score-matched analysis of real-world data

Background

Tiotropium failed to slow the annual rate of forced expiratory volume in 1 second (FEV₁) decline in chronic obstructive pulmonary disease (COPD) patients with <70% predicted FEV₁. However, the rate of FEV₁ decline is known to be faster at early stages, which suggests that the effects of tiotropium may be more prominent in early-stage of COPD patients. The aim of this study was to test the hypothesis that tiotropium modifies the rate of FEV₁ decline in COPD patients with an FEV₁≥70%.

Methods

We retrospectively reviewed the records of COPD patients diagnosed between January 1, 2004, and July 31, 2012, at Seoul National University Hospital, Seoul National University Bundang Hospital, and Seoul Metropolitan Government-Seoul National University Boramae Medical Center. The inclusion criteria were as follows: age ≥40 years, postbron-chodilator (BD) FEV₁≥70% of predicted and FEV₁/FVC (forced vital capacity) <0.70, and spirometry more than two times at certain times of the year. Conversely, the exclusion criteria were as follows: asthma, lung cancer, pulmonary tuberculosis, pulmonary resection, or long-term use of a short-acting muscarinic antagonist. The annual lung function decline in patients using tiotropium was compared with that in patients not using the drug.

Results

Of the 587 patients enrolled in the study, 257 took tiotropium. Following propensity score matching, 404 patients were included in the analysis. The mean annual rate of post-BD FEV₁ decline was 23.9 (tiotropium) and 22.5 (control) mL/yr (P=0.86); corresponding pre-BD values were 30.4 and 21.9 mL/yr (P=0.31), respectively. Mean annual rate of post-BD FVC decline was 55.1 (tiotropium) and 43.5 (control) mL/yr (P=0.33); corresponding pre-BD values were 37.1 and 33.3 mL/yr (P=0.13).

Conclusion

Therefore, tiotropium does not reduce the rate of lung function decline in COPD patients with FEV₁≥70%.

Clinical characteristics of COPD syndrome: A 6-year follow-up study of adult smokers

BACKGROUND

There is little quantitative information about the development of chronic obstructive pulmonary disease (COPD) among adult smokers and of what happens to patients who have already developed COPD.

OBJECTIVES

To examine the development and performance of COPD status over time, and the clinical characteristics of new COPD cases according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2007 and 2011 classifications.

METHODS

Healthy asymptomatic smokers were recruited through newspaper announcements. They filled in questionnaires and had an individualized assessment of their health history during all three visits (visit 1, visit 2 after three years, visit 3 after six years).

RESULTS

Of the eligible 621 heavy smokers, 572 attended visit 2. A total of 513 subjects completed the 6-year follow-up examination. According to GOLD 2007, COPD was present in 22.8% (n = 117) of these smokers. The severity of COPD changed during the years of follow-up. Furthermore, health status and prevalence of chronic respiratory symptoms both in the smokers with normal lung function and in the COPD groups varied over the time period.

CONCLUSIONS

GOLD 2011 recognized the complex patient subgroups better than GOLD 2007. Variability in chronic symptoms or in health status correlated poorly with the severity of airway limitation.

α1-antitrypsin deficiency: what has it ever done for us?

The first five cases of α1-antitrypsin deficiency were originally published in 1963. This changed our whole concept about the pathophysiology of emphysema, including the role of inflammation and, in particular, the role of proteolytic enzymes. However, the observation also had a significant 50-year impact on many aspects of protein biochemistry, genetics, cell biology, and disease concepts outside the lung as well as the study of COPD in general.