Syndrome of Combined Pulmonary Fibrosis and Emphysema: An Official ATS/ERS/JRS/ALAT Research Statement

Impact of coal mine dust exposure and cigarette smoking on lung disease in Appalachian coalminers

INTRODUCTION

Interactions have been demonstrated between cigarette smoking (CS) and occupational exposures to several particles. This study tested the postulate that CS interacts with coal mine dust exposure to impact and change radiological and histological endpoints of coal mine dust lung disease.

METHODS

A retrospective evaluation of coalminers with a high-resolution computed tomography (HRCT) of the chest was conducted at West Virginia University Hospital (2015- 2022). There was a consensus review of both radiology and histology findings and their comparative analysis with a non-miner surgical resection cohort collected from thoracic oncology clinic.

RESULTS

The study cohort (n=556) was divided into groups: coal-/smoking- (8.3%), coal-/smoking+ (26.6%), coal+/smoking- (22.3%), and coal+/smoking+ (42.8%). Miners were older males with a median duration of coal mine work (CMW) of 30-years. Ever-smokers (66% of miner cohort and 76% of non-miner cohort) smoked 35 and 28 composite pack years (CPY) respectively, where miners had greater intensity of smoking (22 vs 18 cigarettes/day) compared to non-miners. On HRCT, 1/3rd and 1/5th of miners had simple and complicated coal workers' pneumoconiosis (sCWP and cCWP), respectively. 35% of ever-smoking miners had radiologic patterns for probable usual interstitial pneumonitis, nonspecific interstitial pneumonitis, desquamative interstitial pneumonitis, and combined pulmonary fibrosis and emphysema. Radiologically, both coal-/smoking+ and coal+/smoking+ showed excessive emphysema (70-80%). Histologically, miners had more fibrosis (47% and 50% in coal+/smoking- and coal+/smoking+ vs. 11% and 28% in coal-/smoking- and coal-/smoking+). Never-smoking miners demonstrated more histological evidence of CWP than ever-smokers (60% and 27%); in addition, they had radiologic and histologic emphysema (30%), radiologic interstitial lung disease (ILD) (14.5%) and histologic evidence of fibrosis (47%). Ever-smokers demonstrated histologic emphysema more frequently (33% and 67% in coal+/smoking- and coal+/smoking+ vs. 24% and 72% in coal-/smoking- and coal-/smoking+). Logistic regression modeling showed the following associations: radiologic and histologic emphysema with CPY; histologic fibrosis, any ILD (not including RB-ILD), CPFE and anthracosis with both CPY and CMW; radiologic RB-ILD inclusive of small-opacities, cCWP with both CMW and silica; and sCWP and pulmonary artery dilation with CMW. Interestingly, CPY≥30 negatively correlated with radiologic cCWP and histologic CWP. Mortality was increased in smokers (14% and 29% in coal+/smoking- and coal+/smoking+ vs. 4% and 20% in coal-/smoking- and coal-/smoking+) with predictors being radiologic ILD, histologic CWP, and related co-morbid diseases including COPD, chronic kidney disease, and gastroesophageal reflux.

CONCLUSION

CS demonstrated a major impact on miners' health including changing radiologic and histologic endpoints of interstitial lung diseases and emphysema.

Advances in Concept and Imaging of Interstitial Lung Disease

Although idiopathic pulmonary fibrosis (IPF) is a type of idiopathic interstitial pneumonia (IIP), it is different from other IIPs. IPF also differs from interstitial lung disease (ILD) with known causes, including connective tissue disease, exposure, cysts and/or airspace filling disease, and sarcoidosis. More than 90% of IPFs demonstrate progressive disease. Non-IPF ILD has been classified as progressive pulmonary fibrosis on the basis of disease behavior (progressive disease that gets worse over time) as opposed to classification based on cause and/or morphologic characteristics. Progressive fibrosis predictors in ILD include demographic characteristics, underlying connective tissue disease, more extensive disease at CT, honeycombing and usual interstitial pneumonia (UIP) pattern at CT, and greater impairment of lung function. Hypersensitivity pneumonitis (HP), a type of ILD, is separated into fibrotic and nonfibrotic types. Extensive peribronchiolar metaplasia supports the diagnosis of fibrotic HP over UIP, as does predominantly peribronchiolar disease with relative subpleural sparing at CT. Interstitial lung abnormality (ILA) is incidentally identified at CT; thus, ILA is under radiologist purview. Subpleural fibrotic ILA is a prognostic imaging biomarker, predictive of worse prognosis. Photon-counting CT can provide high spatial resolutions of up to 125 μm (in-plane) and 200 μm (through-plane) for improved evaluation of abnormalities.

Emphysema or fibrosis progression in patients with combined pulmonary fibrosis and emphysema

BACKGROUND

Patients with combined pulmonary fibrosis and emphysema (CPFE) may experience emphysema or fibrosis progression on chest computed tomography (CT). This study aimed to investigate the relationship and prognosis in CPFE patients with emphysema or fibrosis progression.

METHODS

A total of 188 CPFE patients were included in our retrospective cohort study. The clinical presentations, radiographic features, and laboratory findings of the patients were reviewed.

RESULTS

Among CPFE patients, 28.1 % exhibited emphysema progression and 43.3 % showed fibrosis progression. Different higher tumour markers were observed in the emphysema or fibrosis progression groups. Smoking, definite usual interstitial pneumonia (UIP), and total extent of emphysema were risk factors for emphysema progression. Age, definite UIP, and mediastinal lymph node enlargement were risk factors for fibrosis progression. Patients with fibrosis progression had worse prognoses than patients without fibrosis progression (HR 2.159; 95 % CI, 1.243-3.749; P = 0.006). However, the prognosis was similar between patients with and without emphysema progression (HR 0.839; 95 % CI, 0.429-1.641; P = 0.608). There was no significant interaction between emphysema and fibrosis progression (p > 0.05).

CONCLUSIONS

In CPFE patients, emphysema and fibrosis progression had different higher tumour markers, risk factors, and prognosis effects. There was no significant interaction between emphysema and fibrosis progression. Fibrosis progression had a deleterious effect on prognosis, whereas emphysema progression did not affect prognosis. Therefore, the primary objective of CPFE treatment should be to halt or even reverse the progression of fibrosis. CPFE may be primarily a fibrotic disease, with emphysema being an incidental complication.

Assessment of lung function and severity grading in interstitial lung diseases (% predicted versus z-scores) and association with survival: A retrospective cohort study of 6,808 patients

BACKGROUND

Pulmonary function tests (PFTs) are essential for predicting outcomes in interstitial lung disease (ILD). In 2022, an expert panel recommended using z-scores instead of the traditional % predicted cut-off values to interpret the severity of PFT abnormalities which may lead to discordant classifications in some patients. To assess the magnitude and prognostic impact of this phenomenon we compared these two approaches in predicting all-cause mortality in a large cohort of patients with ILDs.

METHODS AND FINDINGS

We retrospectively analyzed data from a tertiary referral center for patients with ILDs. Absolute FEV1, FVC, TLC, and TLCO values from patients' first presentations were transformed and presented as % predicted and z-scores using the most recent global lung initiative (GLI) reference values. Results were categorized for severity according to % predicted and z-score levels. Predictors of all-cause mortality over a 14-year follow-up were determined using Kaplan-Meier survival analysis and Cox proportional hazards regression. Between January 2009 and March 2023, 6,808 patients with ILDs were evaluated at the National TB and Lung Diseases Research Institute in Warsaw, Poland. Most were diagnosed with sarcoidosis, fibrotic ILD, or non-fibrotic ILD. At their first presentation, 13.2% had airway obstruction, 23.1% had low FVC (indicative of restriction by spirometry), and 45.6% had a reduced lung transfer factor (TLCO). Reclassification of spirometric indices occurred in 26.8% of patients for FEV1 and 24.6% for FVC among those with abnormal results, with most being reassigned to a less severe categories. For TLCO, 28.1% of patients with reduced values were reclassified, with most shifting to more severe categories. During the follow-up, 1,525 (22.4%) of patients died. Both low FVC and low TLCO predicted all-cause mortality, with z-score thresholds showing stronger associations with mortality. A one-unit decrease in the FVC z-score was associated with a 10.3% increase in the risk of death, while a one-unit decrease in TLCO z-score was linked to an over 30% increase in mortality risk. Limitations of this retrospective single-center study include lack of data on cause-specific mortality, potential residual confounding, and limited generalizability to non-Caucasian or younger populations.

CONCLUSIONS

The recently recommended use of z-scores leads to significant reclassification of lung function results in patients with ILDs, largely driven by age. This approach is justified by its stronger prognostic associations. Severe TLCO impairment remains a robust predictor of mortality in ILDs.

Neutrophil-to-lymphocyte ratio as a prognostic marker for lung cancer in combined pulmonary fibrosis and emphysema patients

BACKGROUND

Combined pulmonary fibrosis and emphysema (CPFE) represents a distinct clinical syndrome characterized by the coexistence of upper lobe emphysema and lower lobe fibrosis, with an increased risk of lung cancer (LC) development. This study aimed to detect the clinical features and prognosis of CPFE patients with LC and the ability of neutrophil-to-lymphocyte ratio (NLR) to predict outcomes in those individuals.

METHODS

A retrospective cohort study involving patients diagnosed with CPFE combined with LC between January 2017 and December 2023 was conducted. Clinical characteristics, laboratory parameters and survival data were collected.

RESULTS

A total of 80 CPFE patients with LC were included, with a mean age of 68.1 years, and a male predominance (93.8%). The LCs were predominantly adenocarcinomas (38.8%), with a significant proportion diagnosed at advanced stages (22.5% at stage III, 47.5% at stage IV) and preferential peripheral pulmonary localization (72.5%). CPFE patients with LC had estimated 1-year, 3-year, and 5-year survival rates of 52%, 40%, and 37%, respectively, with a median overall survival of 29.2 months. Multivariate Cox regression analysis revealed that increased NLR [adjusted hazard ratio (HR) 1.180, 95% confidence interval CI 1.029-1.352, p = 0.018] and elevated carcinoembryonic antigen (CEA) (adjusted HR 1.005, 95% CI 1.000-1.010, p = 0.036) were related to an enhanced risk of all-cause mortality. Receiver-operating characteristic analysis identified an NLR cutoff value of 2.6 as a predictor of all-cause death within 24 months [area under the curve = 0.651; specificity = 62.1%; sensitivity = 66.6%; p < 0.05]. Patients with an NLR greater than 2.6 had a significantly greater risk of all-cause death than those with an NLR of 2.6 or less (adjusted HR 2.3, 95% CI 1.197-4.754; p = 0.011).

CONCLUSIONS

The NLR may serve as a cost-effective and widely accessible biomarker for risk stratification, particularly in CPFE patients with advanced-stage LC. In our cohort, an NLR cutoff value of 2.6 provides improved prognostic accuracy in predicting mortality outcomes.

Quantification of progressive pulmonary fibrosis by visual scoring of HRCT images: recommendations from Italian chest radiology experts

Interstitial lung diseases (ILD) constitute a large and heterogeneous group of disorders affecting the lung parenchyma. While idiopathic pulmonary fibrosis (IPF), the most common type of ILD, is the prototype of progressive fibrosis, other forms, collectively termed "progressive pulmonary fibrosis" (PPF), can show a similar clinical course. Detecting chronic fibrosing ILD progression necessitates radiological evidence using high-resolution computed tomography (HRCT), which determines eligibility for treatment. However, assessing the extent of fibrosis and progression on HRCT images is difficult and lacks specific guidelines. Therefore, expert oversight and high-quality visual assessment/scoring of complex disease patterns is essential to monitor disease changes. Twelve Italian chest radiologists deliberated on the current state of quantifying lung fibrosis using existing literature to develop practice-oriented consensus statements to assist radiologists in visually assessing/scoring lung fibrosis on HRCT images in patients with PPF. The resulting statements cover three key areas: (1) technical requirements necessary for accurate HRCT image assessment; (2) an easy-to-use quantification protocol for routine clinical practice; and (3) a multiple specialist approach by combining radiological, clinical, and histopathological findings for the correct diagnosis, prompt detection of PPF, and timely start of antifibrotic treatment. In future, automated quantitative HRCT evaluation will lead to new clinical assessment tools.

The Link Between Sleep-Related Breathing Disorders and Idiopathic Pulmonary Fibrosis: Pathophysiological Mechanisms and Treatment Options-A Review

In recent years, several studies have examined the impact of sleep-disordered breathing (SBD) on the quality of life and prognosis of patients with idiopathic pulmonary fibrosis (IPF). Among these disorders, obstructive sleep apnea (OSA) and nocturnal hypoxemia (NH) are the most prevalent and extensively studied, whereas central sleep apnea (CSA) has only been documented in recent research. The mechanisms underlying the relationship between IPF and SBDs are complex and remain an area of active investigation. Despite growing recognition of SBDs in IPF, no standardized guidelines exist for their management and treatment, particularly in a population characterized by distinct structural pulmonary abnormalities. This review outlines the pathophysiological connections between sleep-breathing disorders (SBDs) and idiopathic pulmonary fibrosis (IPF), as well as current therapeutic options. A comprehensive literature search using PubMed identified relevant studies, confirming the efficacy of CPAP in treating severe OSA and CSA. While high-flow oxygen therapy has not been validated in this patient cohort, it may offer a potential solution for select patients, particularly the elderly and those with low compliance. Conventional oxygen therapy, however, is limited to cases of isolated nocturnal hypoxemia or mild central sleep apnea.

Review of the Diagnosis and Management of Pulmonary Hypertension Associated with Interstitial Lung Disease (ILD-PH)

Pulmonary hypertension associated with interstitial lung disease (ILD-PH) frequently complicates the course of patients with fibrotic ILD. In this narrative review, the authors assess current diagnostic tools and management considerations in ILD-PH patients. ILD-PH is associated with increased morbidity and mortality and may be suggested by the presence of symptoms out of proportion to the extent of the ILD. There are other clues to the presence of PH in the context of ILD including the need for supplemental oxygen, a reduced DLCO especially if accompanied by a disproportionately higher forced vital capacity, imaging demonstrating an enlarged pulmonary artery or a dilated right ventricle, or objective evidence of a reduced exercise capacity. While echocardiography is one screening tool, right heart catheterization remains the gold standard for the diagnosis of PH. When appropriate, treatment with inhaled treprostinil, or possibly other pulmonary vasodilators, may be indicated.

Exercise-induced Right-to-left Shunt in a Patient with Combined Pulmonary Fibrosis and Emphysema

Combined pulmonary fibrosis and emphysema (CPFE) is characterized by emphysematous lesions in the upper lung field and pulmonary fibrosis in the lower lung field and is often associated with pulmonary hypertension and severe exercise-induced hypoxemia (EIH). We herein report a 62-year-old man with CPFE who presented with severe EIH despite relatively preserved lung volumes. Cardiopulmonary exercise testing suggested exercise-induced right-to-left shunt (EIS) through a patent foramen ovale (PFO). EIS was attributed to exercise-induced pulmonary hypertension. In this case report, we highlight the possibility of EIS using PFO for CPFE. We also discuss potential treatments including pharmaceutical interventions and PFO closures.

Oral Pulmonary Arterial Hypertension-Targeted Therapy in Patients With Pulmonary Hypertension due to Interstitial Lung Disease

Background

The aim of the study was to determine whether treatment with oral pulmonary arterial hypertension (PAH)-targeted therapy is associated with functional or hemodynamic improvement in patients with pulmonary hypertension due to interstitial lung disease (PH-ILD).

Methods

We conducted a retrospective review of 1,507 consented patients with pulmonary hypertension (PH) from the University of Chicago PH Registry. Exclusion criteria included: enrollment in PH-related clinical trials, use of inhaled treprostinil or iloprost and prior PAH-targeted therapy initiated before consenting to registry enrollment, thus precluding baseline data. Data analyzed included demographics, interstitial lung disease (ILD) classification, PAH-targeted therapy, functional data, hemodynamics, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) before and after initiation of treatment. Data were analyzed using paired t-test, or related-samples Wilcoxon signed rank test.

Results

Of 37 patients included, 27 (73%) received treatment with one PAH-targeted therapy and nine (24%) received dual therapy. At baseline, median NT-proBNP was 1,498 ng/dL (675 - 3,208), mean pulmonary artery pressure (mPAP) was 45 ± 11 mm Hg, and pulmonary vascular resistance (PVR) of 9 ± 4 Wood units (WU). In patients with measurements both before and after treatment with PAH-targeted therapy, there was a decrease in PVR (n = 13, 8 vs. 5 WU, P < 0.001), an increase in cardiac output (n = 13, 4 vs. 5 L/min, P = 0.014), and a decrease in NT-proBNP levels (n = 26, 1,421 vs. 842 ng/dL, P = 0.045).

Conclusions

In this study, use of PAH-targeted therapy in patients with PH-ILD was associated with statistically significant and clinically meaningful improvements in NT-proBNP and pulmonary hemodynamics.

Incidence of and predictive factors for lung cancer in patients with rheumatoid arthritis: A retrospective long-term follow-up study

OBJECTIVES

The aim of this study was to determine the incidence and predictive factors of lung cancer in rheumatoid arthritis (RA).

METHODS

We conducted a retrospective follow-up study of patients who were diagnosed with RA at our institution between April 2001 and December 2022. Pulmonary complications were evaluated using high-resolution computed tomography (HRCT) at RA diagnosis. Patients were followed until the diagnosis of lung cancer, diagnosis of other malignancies, death, loss to follow-up, or the end of the study.

RESULTS

Among 771 RA patients, 3.5% were diagnosed with combined pulmonary fibrosis and emphysema (CPFE), 4.9% with interstitial lung disease (ILD) alone, and 6.0% with emphysema alone. During follow-up (mean of 9.3 years), the crude incidence rates of lung cancer per 1000 patient-years were 2.9 in all patients, 47.8 in CPFE patients, 10.5 in ILD patients, 11.9 in emphysema patients, and 0.8 in patients without these complications. Only male patients showed a higher incidence of lung cancer compared with the general population. In multivariable Fine-Gray regression analysis, the presence of HRCT-proven CPFE, ILD, and emphysema, and smoking history were identified as predictive factors for lung cancer in RA patients.

CONCLUSIONS

Close monitoring of lung cancer is needed for RA patients with smoking history and pulmonary complications, especially CPFE.

Association of combined pulmonary fibrosis and emphysema in rheumatoid arthritis with high titer of rheumatoid factor and autoimmunity to the lung

Background

Combined pulmonary fibrosis and emphysema (CPFE) commonly coexists with connective tissue diseases (CTD), such as rheumatoid arthritis (RA). However, the risk factors contributing to the development of CTD-CPFE remain largely unidentified. This study aimed to characterize CPFE using a large cohort of consecutive RA patients and to elucidate potential risk factors associated with RA- CPFE development.

Methods

A total of 976 RA patients were enrolled in this cross-sectional study to characterize RA-CPFE. Multiple logistic analyses were conducted to identify potential risk factors for RA-CPFE development. Patient IgG and IgM autoantibodies to primary human bronchial epithelial cells (HBEC) from healthy donors were assessed using flow cytometry.

Findings

Among the 976 RA patients, 414 (42.4%) developed interstitial lung disease (ILD), with 74 (7.6%) experiencing CPFE. In comparison to RA-CPFE patients with centrilobular or paraseptal emphysema, those with panacinar emphysema had higher emphysema scores and decreased pulmonary function parameters. Multiple logistic regression analysis revealed that male gender, cigarette smoking, occupational exposure to dust, high ILD score, high rheumatoid factor (RF) titers, and the presence of anti-SSA were associated with an increased risk for RA-CPFE. Additionally, levels of IgG and IgM autoantibodies to HBEC were elevated in RA-CPFE patients compared to healthy controls and positively correlated with RF levels.

Interpretation

This study is the first to demonstrate the association of RA-CPFE with high titer of RF and the presence of autoantibodies against HBEC, suggesting a link between autoimmunity to the lung and RA-CPFE.

Treatable traits in interstitial lung disease: a narrative review

The interstitial lung diseases (ILDs) are a heterogeneous and complex group of diseases. The treatable trait (TT) model represents a shift in ILD management, away from traditional diagnostic labels towards a more individualised, trait-focused approach. This review explores the application of the TT paradigm to ILD, identifying key traits across the aetiological, pulmonary, extrapulmonary and behavioural domains. By addressing these traits, the TT model offers a framework to improve outcomes in ILD through multidisciplinary management with a precision medicine focus. Further research is necessary to evaluate the overall impact of this TT model on ILD care.

Comorbidities in the idiopathic pulmonary fibrosis and progressive pulmonary fibrosis trial population: a systematic review and meta-analysis

BACKGROUND

Comorbidities can affect drug tolerability and health outcomes in patients with fibrotic interstitial lung disease. This systematic review and meta-analysis evaluated the types and prevalence of comorbidities amongst participants in pharmaceutical randomised controlled trials (RCTs) of idiopathic pulmonary fibrosis (IPF) and progressive pulmonary fibrosis (PPF).

METHODS

Ovid Medline, Embase and CENTRAL databases were searched to identify phase II and III pharmaceutical RCTs of IPF or PPF. Reporting of comorbidities was evaluated, with meta-analyses being performed for the prevalence of different conditions.

RESULTS

34 articles were included, with 23 unique trials for IPF and one for PPF. A mean of 14 (range 1-44) comorbidities per study was reported in the IPF RCTs, with 11 being reported in the PPF RCT. Common comorbidities in the IPF RCT cohorts were systemic hypertension (pooled prevalence 45%, 95% CI 39-50%), hyperlipidaemia (38%, 95% CI 27-49%), gastro-oesophageal reflux disease (45%, 95% CI 36-54%), ischaemic heart disease (18%, 95% CI 13-42%) and diabetes mellitus (16%, 95% CI 13-20%). The PPF trial cohort had similar types and prevalence of comorbidities to those reported in the IPF trial cohorts.

CONCLUSIONS

Reporting of comorbidities varied across previous IPF RCTs, with limited data available for PPF. Prevalence of comorbidities reported in the IPF and PPF trial cohorts appear to be lower than those reported in prospective patient registries. There is a need for careful consideration of trial eligibility criteria with detailed reporting of comorbidities in future pharmaceutical RCTs to better understand the applicability of trial findings to real-world patients.

Prognostic value of a composite physiologic index developed by adding bronchial and hyperlucent volumes quantified via artificial intelligence technology

BACKGROUND

The composite physiologic index (CPI) was developed to estimate the extent of interstitial lung disease (ILD) in idiopathic pulmonary fibrosis (IPF) patients based on pulmonary function tests (PFTs). The CALIPER-revised version of the CPI (CALIPER-CPI) was also developed to estimate the volume fraction of ILD measured by CALIPER, an automated quantitative CT postprocessing software. Recently, artificial intelligence-based quantitative CT image analysis software (AIQCT), which can be used to quantify the bronchial volume separately from the ILD volume, was developed and validated in IPF. The aim of this study was to develop AIQCT-derived CPI formulas to quantify CT abnormalities in IPF and to investigate the associations of these CPI formulas with survival.

METHODS

The first cohort included 116 patients with IPF. In this cohort, ILD, bronchial, and hyperlucent volumes on CT were quantified using AIQCT. New CPI formulas were developed based on PFTs to estimate the volume fraction of ILD (ILD-CPI), the sum of the ILD and bronchial volume fractions (ILDB-CPI), and the sum of the ILD, bronchial and hyperlucent volume fractions (ILDBH-CPI). The associations of the original CPI, the CALIPER-CPI and the AIQCT-derived CPIs with survival were analyzed in the first cohort and in a second cohort of patients with IPF (n = 72).

RESULTS

In the first cohort, over a median observation time of 92.8 months, 79 patients (68.1%) died, and one patient (0.9%) underwent living-donor lung transplantation. The original CPI, the CALIPER-CPI, and all AIQCT-derived CPIs were associated with overall survival (hazard ratios: 1.07-1.22). The C-index of the ILDB-CPI (0.759) was the highest among all AIQCT-derived CPIs and was comparable to that of the original CPI (0.765) and the CALIPER-CPI (0.749). The C-index of the ILDBH-CPI (0.729) was lower than that of the other CPI variables. The second cohort yielded similar C-indices as the first cohort for the original CPI (0.738), CALIPER-CPI (0.757) and ILDB-CPI (0.749).

CONCLUSIONS

The ILDB-CPI can predict the outcomes of IPF patients with a similar performance to that of the original CPI and the CALIPER-CPI. Adding the hyperlucent volume to the CPI formula did not improve its predictive accuracy for mortality.

TRIAL REGISTRATION

None (no health care interventions were performed).

Quantitative Imaging Methods in Combined Pulmonary Fibrosis and Emphysema

TOPIC IMPORTANCE

Combined pulmonary fibrosis and emphysema (CPFE) is an underdiagnosed syndrome in which individuals have variable degrees of pulmonary fibrosis and emphysema. Patients with CPFE have high morbidity, including poor exercise tolerance and increased development of comorbidities. CPFE mortality also seems to outpace that of lone emphysema and pulmonary fibrosis. A major limitation to rigorous, large-scale studies of CPFE has been the lack of a precise definition for this syndrome. A 2022 American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/Latin American Thoracic Association research statement called attention to fundamental gaps in our understanding of CPFE and highlighted the potential use of quantitative imaging techniques to better define CPFE.

REVIEW FINDINGS

Broadly, CPFE has been defined using visual interpretation of chest CT imaging documenting the presence of both emphysema and fibrosis, with varying distributions. When quantitative approaches were involved, varying thresholds of emphysema and fibrosis on imaging have been used across different studies.

SUMMARY

This review is structured into three primary themes, starting with early imaging studies, then evaluating the use of quantitative methods and imaging-based thresholds, both in large population studies and single-center cohorts to define CPFE and assess patient outcomes. It concludes by discussing current challenges and how to focus our efforts so that quantitative imaging methods can effectively address the most pressing clinical dilemmas in CPFE.

Diagnosis and management of hypersensitivity pneumonitis in adults: A position statement from the Thoracic Society of Australia and New Zealand

Hypersensitivity pneumonitis (HP) is an immune-mediated interstitial lung disease (ILD) relating to specific occupational, environmental or medication exposures. Disease behaviour is influenced by the nature of exposure and the host response, with varying degrees of lung inflammation and fibrosis seen within individuals. The differentiation of HP from other ILDs is important due to distinct causes, pathophysiology, prognosis and management implications. This Thoracic Society of Australia and New Zealand (TSANZ) position statement aims to provide an up-to-date summary of the evidence for clinicians relating to the diagnosis and management of HP in adults, in the Australian and New Zealand context. This document highlights recent relevant findings and gaps in the literature for which further research is required.

COPD overlap conditions: Clinical and therapeutic implications

Chronic Obstructive Pulmonary Disease (COPD) is a complex pulmonary condition characterized by chronic airflow limitation. Within the spectrum of COPD, distinct overlap conditions exist, including Asthma-COPD Overlap (ACO), COPD-Obstructive Sleep Apnea (COPD-OSA), Combined Pulmonary Fibrosis and Emphysema (CPFE), and Bronchiectasis-COPD Overlap (BCO). This review provides a comprehensive overview of the clinical and therapeutic implications of these conditions, highlighting the differences in complications compared with COPD alone in addition to the diagnostic challenges of identifying these conditions. Therapeutically tailored approaches are necessary for COPD overlap conditions considering the unique complications that may arise. Optimal pharmacological management, disease-specific interventions, and comprehensive patient-centered care are crucial components of treatment strategies. This review provides insights for healthcare professionals by enhancing their understanding and management of these conditions. This emphasizes the importance of accurate diagnosis and individualized treatment plans, considering the specific complications associated with each COPD overlap condition.

Patient Profile-Based Management with Nintedanib in Patients with Idiopathic Pulmonary Fibrosis

A severe and progressive interstitial lung disease (ILD) known as idiopathic pulmonary fibrosis (IPF) has an unknown etiology with poorly defined mechanisms of development. Among the currently prescribed pharmacological interventions for IPF, nintedanib demonstrates the ability to decelerate the deterioration of lung function and yield positive clinical outcomes. Multiple randomized placebo-controlled trials have confirmed the efficacy and acceptable safety profile of nintedanib. Real-world evidence studies also support the use of nintedanib in IPF, being an efficient and well-tolerated treatment option. It has the potential to stabilize the disease progression in patients with ILD. Patients with IPF frequently have comorbidities like diabetes and hypertension, which can exacerbate the course of disease, reduce quality of life, and decrease treatment adherence. For well-informed decision-making, it is important for healthcare professionals to recognize the position of nintedanib therapy in IPF with comorbidities. The gastrointestinal adverse effects, notably diarrhea, dominate the nintedanib safety profile. These can be effectively controlled by closely monitoring side effects, administering anti-diarrheal and anti-emetic drugs, reducing the nintedanib dose, and discontinuing it in case of severe symptoms with an option to reintroduce the treatment after side effects subside. Symptomatic interventions and monitoring of liver enzymes may reduce the occurrence of permanent treatment discontinuations.

An underrecognized phenotype of pulmonary emphysema with marked pulmonary gas exchange but with mild or moderate airway obstruction

In patients with pulmonary emphysema and mild to moderate airflow limitation, one does not expect the features marked exertional dyspnea and hypoxemia as well as a profound decrease in diffusing capacity of the lung for carbon monoxide (DLCO). Here we describe this phenotype and its prognosis. From our database, we retrospectively selected cases associating emphysema, exertional breathlessness, O2 requirement at least upon exercise, forced expiratory volume in 1 sec (FEV1) ≥ 50% predicted, and DLCO ≤ 50% predicted, without associated combined pulmonary fibrosis and emphysema, right-to-left shunt, or severe pulmonary hypertension. Over a 12-year period, we identified 16 patients with emphysema and the above presentation. At the initial evaluation, the median age was 62 years (interquartile range 53.8-68.9). The median FEV1 and DLCO% predicted and mean pulmonary artery pressure were 86 (65-95)%, 38 (31-41)%, and 20 (17-25) mm Hg, respectively. On room air, the median arterial partial pressure of oxygen and partial pressure of carbon dioxide in arterial blood were 63.5 (55.8-69) mm Hg and 34.5 (31-36) mm Hg with increased median alveolar-arterial oxygen difference (46 [39-51] mm Hg). After the initial evaluation, the respiratory condition worsened in 13 of 14 (92.8%) patients with one or more re-evaluations (median follow-up 2.6 [0.9-5.8] years). In 12, lung transplantation was considered. Four patients died after 5.8, 5.7, 7.1, and 0.8 years of follow-up, respectively. We describe an underrecognized phenotype of pulmonary emphysema featuring a particular profile characterized by marked exertional dyspnea, impaired pulmonary gas exchange with low DLCO and marked oxygen desaturation at least on exercise but with mild or moderate airway obstruction.

Pharmacological Treatment of Interstitial Lung Diseases: A Novel Landscape for Inhaled Agents

Interstitial lung diseases (ILDs) encompass a heterogeneous group of over 200 disorders that require individualized treatment. Antifibrotic agents, such as nintedanib and pirfenidone, have remarkably revolutionized the treatment landscape of patients with idiopathic pulmonary fibrosis (IPF). Moreover, the approval of nintedanib has also expanded the therapeutic options for patients with progressive pulmonary fibrosis other than IPF. However, despite recent advances, current therapeutic strategies based on antifibrotic agents and/or immunomodulation are associated with non-negligible side effects. Therefore, several studies have explored the inhalation route aiming to spread higher local concentrations while limiting systemic toxicity. In this review, we examined the currently available literature about preclinical and clinical studies testing the efficacy and safety of inhalation-based antifibrotics, immunomodulatory agents, antioxidants, mucolytics, bronchodilators, and vasodilator agents in ILDs.

Correlation between CT-based phenotypes and serum biomarker in interstitial lung diseases

BACKGROUND

The quantitative analysis of computed tomography (CT) and Krebs von den Lungen-6 (KL-6) serum level has gained importance in the diagnosis, monitoring, and prognostication of interstitial lung disease (ILD). However, the associations between quantitative analysis of CT and serum KL-6 level remain poorly understood.

METHODS

In this retrospective observational study conducted at tertiary hospital between June 2020 and March 2022, quantitative analysis of CT was performed using the deep learning-based method including reticulation, ground glass opacity (GGO), honeycombing, and consolidation. We investigated the associations between CT-based phenotypes and serum KL-6 measured within three months of the CT scan. Furthermore, we evaluated the performance of the combined CT-based phenotypes and KL-6 levels in predicting hospitalizations due to respiratory reasons of ILD patients.

RESULTS

A total of 131 ILD patients (104 males) with a median age of 67 years were included in this study. Reticulation, GGO, honeycombing, and consolidation extents showed a positive correlation with KL-6 levels. [Reticulation, correlation coefficient (r) = 0.567, p < 0.001; GGO, r = 0.355, p < 0.001; honeycombing, r = 0.174, p = 0.046; and consolidation, r = 0.446, p < 0.001]. Additionally, the area under the ROC of the combined reticulation and KL-6 for hospitalizations due to respiratory reasons was 0.810 (p < 0.001).

CONCLUSIONS

Quantitative analysis of CT features and serum KL-6 levels ascertained a positive correlation between the two. In addition, the combination of reticulation and KL-6 shows potential for predicting hospitalizations of ILD patients due to respiratory causes. The combination of reticulation, focusing on phenotypic change in lung parenchyma, and KL-6, as an indicator of lung injury extent, could be helpful for monitoring and predicting the prognosis of various types of ILD.

Emerging multimodality imaging techniques for the pulmonary circulation

Pulmonary hypertension (PH) remains a challenging condition to diagnose, classify and treat. Current approaches to the assessment of PH include echocardiography, ventilation/perfusion scintigraphy, cross-sectional imaging using computed tomography and magnetic resonance imaging, and right heart catheterisation. However, these approaches only provide an indirect readout of the primary pathology of the disease: abnormal vascular remodelling in the pulmonary circulation. With the advent of newer imaging techniques, there is a shift toward increased utilisation of noninvasive high-resolution modalities that offer a more comprehensive cardiopulmonary assessment and improved visualisation of the different components of the pulmonary circulation. In this review, we explore advances in imaging of the pulmonary vasculature and their potential clinical translation. These include advances in diagnosis and assessing treatment response, as well as strategies that allow reduced radiation exposure and implementation of artificial intelligence technology. These emerging modalities hold the promise of developing a deeper understanding of pulmonary vascular disease and the impact of comorbidities. They also have the potential to improve patient outcomes by reducing time to diagnosis, refining classification, monitoring treatment response and improving our understanding of disease mechanisms.

Transplantation, bridging, and support technologies in pulmonary hypertension

Despite the progress made in medical therapies for treating pulmonary hypertension (PH), a subset of patients remain susceptible to developing a maladaptive right ventricular phenotype. The effective management of end-stage PH presents substantial challenges, necessitating a multidisciplinary approach and early identification of patients prone to acute decompensation. Identifying potential transplant candidates and assessing the feasibility of such a procedure are pivotal tasks that should be undertaken early in the treatment algorithm. Inclusion on the transplant list is contingent upon a comprehensive risk assessment, also considering the specific type of PH and various factors affecting waiting times, all of which should inform the decision-making process. While bilateral lung transplantation is the preferred option, it demands expert intra- and post-operative management to mitigate the heightened risks of pulmonary oedema and primary graft dysfunction in PH patients. Despite the availability of risk assessment tools, the occurrence of acute PH decompensation episodes can be unpredictable, potentially leading to refractory right ventricular failure even with optimal medical intervention, necessitating the use of rescue therapies. Advancements in right ventricular assist techniques and adjustments to graft allocation protocols for the most critically ill patients have significantly enhanced the survival in intensive care, affording the opportunity to endure while awaiting an urgent transplant. Given the breadth of therapeutic options available, specialised centres capable of delivering comprehensive care have become indispensable for optimising patient outcomes. These centres are instrumental in providing holistic support and management tailored to the complex needs of PH patients, ultimately enhancing their chances of a successful transplant and improved long-term prognosis.

Pulmonary hypertension associated with lung diseases

Pulmonary hypertension (PH) associated with chronic lung disease (CLD) is both common and underrecognised. The presence of PH in the setting of lung disease has been consistently shown to be associated with worse outcomes. Recent epidemiological studies have advanced understanding of the heterogeneity of this patient population and shown that defining both the specific type of CLD as well as the severity of PH (i.e. deeper phenotyping) is necessary to inform natural history and prognosis. A systematic diagnostic approach to screening and confirmation of suspected PH in CLD is recommended. Numerous uncontrolled studies and one phase 3 randomised, controlled trial have suggested a benefit in treating PH in some patients with CLD, specifically those with fibrotic interstitial lung disease (ILD). However, other studies in diseases such as COPD-PH showed adverse outcomes with some therapies. Given the expanding list of approved pharmacological treatments for pulmonary arterial hypertension, developing a treatment algorithm for specific phenotypes of CLD-PH is required. This article will summarise existing data in COPD, ILD and other chronic lung diseases, and provide recommendations for classification of CLD-PH and approach to the diagnosis and management of these challenging patients.

Pulmonary vascular disease in chronic lung diseases: cause or comorbidity?

PURPOSE OF REVIEW

To provide timely and relevant insights into the complex relationship between pulmonary vascular disease (PVD) and chronic lung disease (CLD), focusing on the causative and consequential dynamics between these conditions.

RECENT FINDINGS

There are shared pathogenic mechanisms between pulmonary arterial hypertension (PAH) and group 3 pulmonary hypertension, including altered expression of mediators and growth factors implicated in both conditions. Factors such as hypoxia, hypoxemia, and hypercapnia also contribute to pulmonary vascular remodelling and endothelial dysfunction. However, the role of hypoxia as the sole driver of pulmonary hypertension in CLD is being reconsidered, particularly in chronic obstructive pulmonary disease (COPD), with evidence suggesting a potential role for cigarette smoke products in initiating pulmonary vascular impairment. On the other hand, interstitial lung disease (ILD) encompasses a group of heterogeneous lung disorders characterized by inflammation and fibrosis of the interstitium, leading to impaired gas exchange and progressive respiratory decline, which could also play a role as a cause of pulmonary hypertension.

SUMMARY

Understanding the intricate interplay between the pulmonary vascular compartment and the parenchymal and airway compartments in respiratory disease is crucial for developing effective diagnostic and therapeutic strategies for patients with PVD and CLD, with implications for both clinical practice and research.

Impact of an expert-derived, quick hands-on tool on classifying pulmonary hypertension in chest computed tomography: a study on inexperienced readers using RAPID-CT-PH

PURPOSE

To test the inter-reader agreement in classifying pulmonary hypertension (PH) on chest contrast-enhanced computed tomography (CECT) between a consensus of two cardio-pulmonary-devoted radiologists (CRc) and inexperienced readers (radiology residents, RRs) when using a CECT-based quick hands-on tool built upon PH imaging literature, i.e., the "Rapid Access and Practical Information Digest on Computed Tomography for PH-RAPID-CT-PH".

MATERIAL AND METHODS

The observational study retrospectively included 60 PH patients who underwent CECT between 2015 and 2022. Four RRs independently reviewed all CECTs and classified each case into one of the five PH groups per the 2022 ESC/ERS guidelines. While RR3 and RR4 (RAPID-CT-PH group) used RAPID-CT-PH, RR1 and RR2 (control group) did not. RAPID-CT-PH and control groups' reports were compared with CRc using unweighted Cohen's Kappa (k) statistics. RRs' report completeness and reporting time were also compared using the Wilcoxon-Mann-Whitney test.

RESULTS

The inter-reader agreement in classifying PH between the RAPID-CT-PH group and CRc was substantial (k = 0.75 for RR3 and k = 0.65 for RR4); while, it was only moderate for the control group (k = 0.57 for RR1 and k = 0.49 for RR2). Using RAPID-CT-PH resulted in significantly higher report completeness (all p < 0.0001) and significantly lower reporting time (p < 0.0001) compared to the control group.

CONCLUSION

RRs using RAPID-CT-PH showed a substantial agreement with CRc on CECT-based PH classification. RAPID-CT-PH improved report completeness and reduced reporting time. A quick hands-on tool for classifying PH on chest CECT may help inexperienced radiologists effectively contribute to the PH multidisciplinary team.

The PROgnostic ModEl for chronic lung disease (PRO-MEL): development and temporal validation

BACKGROUND

Patients with chronic lung diseases (CLDs), defined as progressive and life-limiting respiratory conditions, experience a heavy symptom burden as the conditions become more advanced, but palliative referral rates are low and late. Prognostic tools can help clinicians identify CLD patients at high risk of deterioration for needs assessments and referral to palliative care. As current prognostic tools may not generalize well across all CLD conditions, we aim to develop and validate a general model to predict one-year mortality in patients presenting with any CLD.

METHODS

A retrospective cohort study of patients with a CLD diagnosis at a public hospital from July 2016 to October 2017 was conducted. The outcome of interest was all-cause mortality within one-year of diagnosis. Potential prognostic factors were identified from reviews of prognostic studies in CLD, and data was extracted from electronic medical records. Missing data was imputed using multiple imputation by chained equations. Logistic regression models were developed using variable selection methods and validated in patients seen from January 2018 to December 2019. Discriminative ability, calibration and clinical usefulness of the model was assessed. Model coefficients and performance were pooled across all imputed datasets and reported.

RESULTS

Of the 1000 patients, 122 (12.2%) died within one year. Patients had chronic obstructive pulmonary disease or emphysema (55%), bronchiectasis (38%), interstitial lung diseases (12%), or multiple diagnoses (6%). The model selected through forward stepwise variable selection had the highest AUC (0.77 (0.72-0.82)) and consisted of ten prognostic factors. The model AUC for the validation cohort was 0.75 (0.70, 0.81), and the calibration intercept and slope were - 0.14 (-0.54, 0.26) and 0.74 (0.53, 0.95) respectively. Classifying patients with a predicted risk of death exceeding 0.30 as high risk, the model would correctly identify 3 out 10 decedents and 9 of 10 survivors.

CONCLUSIONS

We developed and validated a prognostic model for one-year mortality in patients with CLD using routinely available administrative data. The model will support clinicians in identifying patients across various CLD etiologies who are at risk of deterioration for a basic palliative care assessment to identify unmet needs and trigger an early referral to palliative medicine.

TRIAL REGISTRATION

Not applicable (retrospective study).

Serum Krebs von den Lungen-6 as a potential biomarker for distinguishing combined pulmonary fibrosis and emphysema from chronic obstructive pulmonary disease: A retrospective study

Background

The presence of fibrotic interstitial lung disease (ILD) is relatively common in patients with emphysema. This has been designated combined pulmonary fibrosis and emphysema (CPFE). CPFE had worse prognosis than emphysema alone. Krebs von den Lungen-6 (KL-6) levels as a biomarker of alveolar type 2 epithelial cell injury, which is widely used to identify the presence of ILD, whether it can differentiate CPFE from COPD remains unknown.

Methods

259 patients from Xiangya Hospital with diagnosis of COPD, with or without ILD, and who had KL-6 tests were recruited for this retrospective analysis. Recorded data included demographic information, comorbidities, inflammatory biomarkers. Results of CT and pulmonary function tests were collected one week before or after KL-6 measurements.

Results

Among 259 patients, 52 patients were diagnosed with CPFE. The mean age was 67.39 ± 8.14 yeas. CPFE patients had higher ratio of rheumatic diseases (21.2 % vs 7.2 %, P = 0.003). CPFE patients exhibited higher values of FEV1 (1.97 vs 1.57, P = 0.002) and FEV1/FVC ratio (69.46 vs 57.64, P < 0.001) compared to COPD patients. CPFE patients had higher eosinophil counts, percentage of eosinophils, lactate dehydrogenase, total bilirubin levels and lower platelet counts. Serum KL-6 levels were higher in CPFE group compared to COPD group (574.95 vs 339.30 U/mL, P < 0.001). Multiple logistic regression showed that KL-6 level was an independent predictive factor for the presence of ILD among COPD patients. The AUC of serum KL-6 levels to differentiate CPFE was 0.711, with 95 % CI being 0.635 to 0.787. The cutoff point of KL-6 level was 550.95 U/mL with 57.7 % sensitivity and 79.7 % specificity for the discrimination of CPFE from COPD.

Conclusion

CPFE patients show higher KL-6 levels compared to isolated COPD, suggesting the potential of KL-6 as a practical screening tool for interstitial lung disease, specifically CPFE. A KL-6 threshold of 550.95 U/mL in COPD patients may indicate a high need for high-resolution chest computed tomography to detect fibrosis.

[Smoking-related interstitial lung disease : Radiological findings, histopathological correlations, and clinical observations]

CLINICAL/METHODOLOGICAL ISSUE

Identifying smoking-related interstitial lung diseases (SRILD) in smokers is challenging, as clinical manifestations can be nonspecific, and there is a variety of SRILD entities that not only interconnect but can also overlap.

RADIOLOGICAL STANDARD PROCEDURES

In diagnosing SRILD, imaging techniques such as high-resolution computed tomography (HRCT) allow the identification of characteristic features, serving as crucial pieces of the puzzle for definitive differentiation.

PERFORMANCE

Studies have demonstrated that HRCT exhibits a sensitivity of approximately 80-90% in identifying SRILD, with a specificity around 70-80%. The conclusive diagnosis often requires a correlation between histopathological findings and clinical observations.

PRACTICAL RECOMMENDATIONS

Regular monitoring of smokers, especially when experiencing symptoms like shortness of breath and cough, coupled with a comprehensive diagnosis of SRILD, is crucial for accurate identification and individualized therapy.

[Interstitial lung diseases : From imaging to treatment]

BACKGROUND

The role of radiology in the diagnosis of interstitial lung diseases (ILDs) has evolved over time, in part replacing histology. Radiology now represents a pillar of diagnostics and monitoring in ILDs.

OBJECTIVE

To what extent does radiology influence diagnostics and treatment in ILDs?

MATERIALS AND METHODS

A literature review was conducted, and current findings were discussed in the context of clinical data.

RESULTS

Radiology plays a crucial role in the diagnosis of ILDs. Within the framework of the multidisciplinary conference, it provides specific CT patterns such as usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP), and organizing pneumonia (OP), or helps in identifying cystic lung diseases. Multicompartment diseases can be detected, and pulmonary hypertension or extrapulmonary involvement of the respective diseases can be suspected. Progressive pulmonary fibrosis requires radiologic assessment as one of the required criteria. Interstitial lung abnormalities are usually detected by radiological studies performed for an unrelated indication.

CONCLUSION

Radiology plays an important role within the multidisciplinary conference to determine both diagnosis and treatment with antifibrotic or anti-inflammatory drugs, or a combination of both.

The link between smoking, emphysema, and fibrosis: A retrospective cohort study

INTRODUCTION

The presence of emphysema is common in patients with interstitial lung disease (ILD), which is designated as combined pulmonary fibrosis and emphysema (CPFE). This study aimed to examine the association between smoking, emphysema, and fibrosis in ILD patients.

METHODS

A total of 800 patients hospitalized for ILD at the affiliated hospital of Qingdao University, Shandong, Qingdao, China, from December 2012 to December 2020 were included in our retrospective cohort study. Participants were divided into CPFE and non-CPFE groups. The patients' clinical presentations and radiographic and laboratory findings were reviewed and compared. The two groups were then divided and compared based on smoking status. Kaplan-Meier survival analysis with log-rank testing and multivariable Cox proportional hazards regression analysis were used to compare all-cause mortality.

RESULTS

Emphysema was present in 188 (23.5%) ILD patients. Smoking was associated with increased odds of CPFE (adjusted odds ratio, AOR=2.13; 95% CI: 1.33-3.41, p=0.002). The CPFE patients had a comparable risk of death to non-CPFE patients (adjusted hazard ratio, AHR=0.89; 95% CI: 0.64-1.24, p=0.493). Smoking was not a risk prognostic factor in the whole group (AHR=1.34; 95% CI: 0.90-1.99, p=0.152) or the CPFE group (AHR=0.90; 95% CI: 0.43-1.86, p=0.771). However, a significant prognostic difference between smokers and non-smokers was found in the non-CPFE group (AHR=1.62; 95% CI: 1.02-2.58, p=0.042). In ILD patients, smoking pack-years were weakly correlated with total centrilobular emphysema (CLE) scores and total fibrosis scores (TFS), but not with total emphysema scores (TES); TFS were weakly correlated with TES.

CONCLUSIONS

CPFE did not affect the prognosis of ILD. Smoking was a risk but not a prognostic factor for CPFE. However, smoking was associated with worse survival in non-CPFE patients. There was an intricate association among smoking, emphysema, and fibrosis in ILD patients.

Measuring lung diffusing capacity: an opportunity for improved medical surveillance and disability evaluation of coal miners

OBJECTIVES

Spirometry is the primary lung function test utilised for medical surveillance and disability examination for coal mine dust lung disease. However, spirometry likely underestimates physiologic impairment. We sought to characterise abnormalities of single-breath diffusing capacity for carbon monoxide (DLCO) among a population of former coal miners.

METHODS

Data from 3115 former coal miners evaluated at a West Virginia black lung clinic between 2006 and 2015 were retrospectively analysed to study the association between diffusion impairment (abnormally low DLCO), resting spirometry and the presence and severity of coal workers' pneumoconiosis on chest radiography. We developed ordinary least squares linear regression models to evaluate factors associated with per cent predicted DLCO (DLCOpp).

RESULTS

Diffusion impairment was identified in 20.2% of subjects. Ten per cent of all miners with normal spirometry had diffusion impairment including 7.4% of never smokers. The prevalence of diffusion impairment increased with worsening radiographic category of pneumoconiosis. Mean DLCOpp decreased with increasing small opacity profusion subcategory in miners without progressive massive fibrosis. Linear regression analysis also showed significant decreases in DLCOpp with increasing small opacity profusion and presence of large opacities.

CONCLUSIONS

Diffusion impairment is common among former coal miners, including among never smokers, miners without radiographic pneumoconiosis and miners with normal spirometry. These findings demonstrate the value of including DLCO testing in disability examinations of former coal miners and an important role for its use in medical surveillance of working miners to detect early chronic lung disease.

Scoping review of post-TB pulmonary vascular disease: Proceedings from the 2nd International Post-Tuberculosis Symposium

Tuberculosis (TB) may cause significant long-term cardiorespiratory complications, of which pulmonary vascular disease is most under-recognized. TB is rarely listed as a cause of pulmonary hypertension (PH) in most PH guidelines, yet PH may develop at various stages in the time course of TB, from active infection through to the post-TB period. Predisposing risk factors for the development of PH are likely multifactorial, involving active TB disease and post-TB lung disease (PTLD), host-related and environment-related factors. Moreover, post-TB PH should likely be classified in Group 3 PH, with the pathogenesis similarly complex and multifactorial as other Group 3 PH causes. Identifying risk factors that predispose to post-TB PH may aid in developing risk stratification criteria for early identification and referral for confirmatory diagnostic tests. Given that universal screening for PH in TB survivors may be impractical and unfeasible, a targeted screening approach for high-risk individuals would be sensible. In this scoping review of post-TB PH, resulting from the proceedings of the 2nd International Post-Tuberculosis Symposium, we aim to describe the epidemiology, risk factors, and pathophysiology of post-TB PH. We emphasize diagnosing PH with an alternative set of diagnostic guidelines in resource-constrained settings where right heart catheterization may not be feasible. Research to describe the burden and distribution of post-TB PH should be prioritized as there is a current gap in knowledge regarding the prevalence and incidence of post-TB PH among persons with TB.

Why making smoking cessation a priority for rare interstitial lung disease smokers?

This review aims to discuss the complex relationship between smoking and interstitial lung diseases (ILDs), emphasizing the significant morbidity and mortality associated with these conditions. While the etiology of ILDs remains multifactorial, cigarette smoking emerges as a prominent modifiable risk factor implicated in their pathogenesis and progression. This narrative review will provide insight into smoking-associated interstitial lung diseases and personalised approaches to smoking cessation. Epidemiological studies consistently link smoking to ILDs such as idiopathic pulmonary fibrosis (IPF), respiratory bronchiolitis-associated ILD (RB-ILD), and desquamative interstitial pneumonia (DIP), highlighting the urgent need for comprehensive tobacco cessation strategies. Despite the established benefits of smoking cessation, adherence to cessation programs remains challenging due to nicotine addiction, psychological factors, and social influences. The modest success rates of smoking cessation in ILD patients, emphasises the importance of tailored interventions and ongoing support is needed to overcome barriers and to improve outcomes of quitting smoking in this category of vulnerable patients.

Deleterious impact of trivial to severe interstitial pneumonia and emphysema on mortality and acute exacerbation of interstitial pneumonia in patients with lung cancer: a retrospective cohort study

BACKGROUND

Interstitial pneumonia and emphysema may complicate patients with lung cancer. However, clinical significance of trivial and mild pulmonary abnormalities remains unclear. In this study, we aimed to investigate whether trivial and mild interstitial pneumonia and emphysema, in addition to their advanced forms, impact the prognosis and lead to acute exacerbation of interstitial pneumonia (AEIP) in patients with lung cancer.

METHODS

This retrospective cohort study was conducted at a tertiary hospital and included patients with lung cancer. Computed tomography images were evaluated using the interstitial lung abnormality (ILA) score for interstitial pneumonia, which included no ILA, equivocal ILA, ILA, interstitial lung disease (ILD), and the Goddard score for emphysema. Cox analyses were performed using the ILA and Goddard scores as the main explanatory variables, adjusting for multiple covariates.

RESULTS

Among 1,507 patients with lung cancer, 1,033 had no ILA, 160 had equivocal ILA, 174 had ILA, and 140 had ILD. In total, 474 patients (31.5%) exhibited interstitial pneumonia and 638 (42.3%) showed emphysema. The log-rank trend test showed that survival probability was significantly better in patients with no ILA, followed by those with equivocal ILA, ILA, and ILD (P < 0.001). After adjustment, the ILA and Goddard scores remained significant variables for increased hazard ratios (HR) for mortality: no ILA (HR, 1.00: reference), equivocal ILA (HR, 1.31; 95% confidence interval [CI], 1.18-1.46; P < 0.001), ILA (HR, 1.71; 95% CI, 1.39-2.12; P < 0.001), ILD (HR, 2.24; 95% CI, 1.63-3.09; P < 0.001), and Goddard score (HR, 1.03; 95% CI, 1.01-1.06; P < 0.010). Moreover, both scores were associated with increased cause-specific HRs for AEIP.

CONCLUSION

Our results revealed that approximately one-third of patients with lung cancer had interstitial pneumonia when incorporating trivial and mild cases. Because interstitial pneumonia and emphysema, ranging from trivial to severe, significantly impact mortality and AEIP in patients with lung cancer, we should identify even trivial and mild cases of these pulmonary abnormalities among patients with lung cancer in addition to the advanced ones.

Analysis of clinical characteristics and prognosis of lung cancer patients with CPFE or COPD: a retrospective study

BACKGROUND

Lung cancer (LC) commonly occurs in patients with combined pulmonary fibrosis and emphysema (CPFE) and chronic obstructive pulmonary disease (COPD), but comparative research is limited. This study examines clinical characteristics, treatments, and prognosis in LC patients with CPFE or COPD.

METHODS

The retrospective study involved 75 lung cancer patients with CPFE and 182 with COPD. It analyzed clinical features, tumor pathology, pulmonary function, laboratory parameters, and treatment responses.

RESULTS

Notable differences were found between the CPFE + LC and COPD + LC groups. Both groups were mostly elderly, male smokers. The CPFE + LC group had higher BMI and more adenocarcinoma and squamous cell carcinoma, while COPD + LC had predominantly squamous cell carcinoma. CPFE + LC tumors were mostly in the lower lobes; COPD + LC's were in the upper lobes. The CPFE + LC group showed higher tumor metastasis rates, more paraseptal emphysema, and elevated levels of TG, CEA, NSE, and Killer T Cells. In advanced stages (IIIB-IV), the CPFE + LC group receiving first-line treatment had shorter median progression-free survival (PFS) and a higher risk of progression or death than the COPD + LC group, regardless of whether it was non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). No significant PFS difference was found within CPFE + LC between chemotherapy and immunotherapy, nor in immune-related adverse events between groups, with interstitial pneumonia being common.

CONCLUSION

This study emphasizes distinct lung cancer characteristics in CPFE or COPD patients, highlighting the need for tailored diagnostic and treatment approaches. It advocates for further research to improve care for this high-risk group.

Smoking-Related Interstitial Lung Disease and Emphysema

Diagnosis and treatment of patients with smoking-related lung diseases often requires multidisciplinary contributions to optimize care. Imaging plays a key role in characterizing the underlying disease, quantifying its severity, identifying potential complications, and directing management. The primary goal of this article is to provide an overview of the imaging findings and distinguishing features of smoking-related lung diseases, specifically, emphysema/chronic obstructive pulmonary disease, respiratory bronchiolitis-interstitial lung disease, smoking-related interstitial fibrosis, desquamative interstitial pneumonitis, combined pulmonary fibrosis and emphysema, pulmonary Langerhans cell histiocytosis, and E-cigarette or vaping related lung injury.

Interstitial Lung Disease Associated with Systemic Sclerosis

Systemic sclerosis (SSc) is a rare autoimmune disease characterized by a tripod combining vasculopathy, fibrosis, and immune-mediated inflammatory processes. The prevalence of interstitial lung disease (ILD) in SSc varies according to the methods used to detect it, ranging from 25 to 95%. The fibrotic and vascular pulmonary manifestations of SSc, particularly ILD, are the main causes of morbidity and mortality, contributing to 35% of deaths. Although early trials were conducted with cyclophosphamide, more recent randomized controlled trials have been performed to assess the efficacy and tolerability of several medications, mostly mycophenolate, rituximab, tocilizumab, and nintedanib. Although many uncertainties remain, expert consensus is emerging to optimize the therapeutic management and to provide clinicians with evidence-based clinical practice guidelines for patients with SSc-ILD. This article provides an overview, in the light of the latest advances, of the available evidence for the diagnosis and management of SSc-ILD.

Smoking-Related Interstitial Lung Disease: Historical Perspective and Advances in the Twenty-first Century

In the twenty- first century, there is widespread agreement that in addition to lung cancer, emphysema, and chronic bronchitis, cigarette smoking causes accumulation of pigmented macrophages, interstitial fibrosis, and Langerhans cell proliferation in various permutations. These histologic changes remain subclinical in some patients and produce clinical manifestations and imaging abnormalities in others. Debate surrounds terminology of these lesions, which are often grouped together under the umbrella of "smoking-related interstitial lung disease." This review summarizes modern concepts in our understanding of these abnormalities and explains how the recognition of smoking-related interstitial fibrosis has advanced the field.

Central Role of CT in Management of Pulmonary Fibrosis

With the approval of antifibrotic medications to treat patients with idiopathic pulmonary fibrosis and progressive pulmonary fibrosis, radiologists have an integral role in diagnosing these entities and guiding treatment decisions. CT features of early pulmonary fibrosis include irregular thickening of interlobular septa, pleura, and intralobular linear structures, with subsequent progression to reticular abnormality, traction bronchiectasis or bronchiolectasis, and honeycombing. CT patterns of fibrotic lung disease can often be reliably classified on the basis of the CT features and distribution of the condition. Accurate identification of usual interstitial pneumonia (UIP) or probable UIP patterns by radiologists can obviate the need for a tissue sample-based diagnosis. Other entities that can appear as a UIP pattern must be excluded in multidisciplinary discussion before a diagnosis of idiopathic pulmonary fibrosis is made. Although the imaging findings of nonspecific interstitial pneumonia and fibrotic hypersensitivity pneumonitis can overlap with those of a radiologic UIP pattern, these entities can often be distinguished by paying careful attention to the radiologic signs. Diagnostic challenges may include misdiagnosis of fibrotic lung disease due to pitfalls such as airspace enlargement with fibrosis, paraseptal emphysema, recurrent aspiration, and postinfectious fibrosis. The radiologist also plays an important role in identifying complications of pulmonary fibrosis-pulmonary hypertension, acute exacerbation, infection, and lung cancer in particular. In cases in which there is uncertainty regarding the clinical and radiologic diagnoses, surgical biopsy is recommended, and a multidisciplinary discussion among clinicians, radiologists, and pathologists can be used to address diagnosis and management strategies. This review is intended to help radiologists diagnose and manage pulmonary fibrosis more accurately, ultimately aiding in the clinical management of affected patients. ©RSNA, 2024 Supplemental material is available for this article.

First Report of the Prevalence at Baseline and after 1-Year Follow-Up of Treatable Traits in Interstitial Lung Diseases

Different factors, not limited to the lung, influence the progression of ILDs. A "treatable trait" strategy was recently proposed for ILD patients as a precision model of care to improve outcomes. However, no data have been published so far on the prevalence of TTs in ILD. A prospective, observational, cohort study was conducted within the ILD Program at the IRCCS Humanitas Research Hospital (Milan, Italy) between November 2021 and November 2023. TTs were selected according to recent literature and assigned during multidisciplinary discussion (MDD) to one of the following categories: pulmonary, etiological, comorbidities, and lifestyle. Patients were further divided into four groups according to their post-MDD diagnosis: idiopathic ILD, sarcoidosis, connective tissue disease-ILD, and other ILD. The primary study outcome was the prevalence of each TT in the study population. A total of 116 patients with ILD [63.9% male; median (IQR) age: 69 (54-78) years] were included in the study. All the TTs identified in the literature were found in our cohort, except for intractable chronic cough. We also recognized differences in TTs across the ILD groups, with less TTs in patients with sarcoidosis. This analysis provides the first ancillary characterization of TTs in ILD patients in a real setting to date.

Cluster analysis identifies novel real-world lung disease-pulmonary hypertension subphenotypes: implications for treatment response

Background

Clinical trials repurposing pulmonary arterial hypertension (PAH) therapies to patients with lung disease- or hypoxia-pulmonary hypertension (PH) (classified as World Health Organization Group 3 PH) have failed to show a consistent benefit. However, Group 3 PH clinical heterogeneity suggests robust phenotyping may inform detection of treatment-responsive subgroups. We hypothesised that cluster analysis would identify subphenotypes with differential responses to oral PAH therapy.

Methods

Two k-means analyses were performed on a national cohort of US veterans with Group 3 PH; an inclusive model (I) of all treated patients (n=196) and a haemodynamic model (H) limited to patients with right heart catheterisations (n=112). The primary outcome was organ failure or all-cause mortality by cluster. An exploratory analysis evaluated within-cluster treatment effects.

Results

Three distinct clusters of Group 3 PH patients were identified. In the inclusive model (C1I n=43, 21.9%; C2I n=102, 52.0%; C3I n=51, 26.0%), lung disease and spirometry drove cluster assignment. By contrast, in the haemodynamic model (C1H n=44, 39.3%; C2H n=43, 38.4%; C3H n=25, 22.3%), right heart catheterisation data surpassed the importance of lung disease and spirometry. In the haemodynamic model, compared to C3H, C1H experienced the greatest hazard for respiratory failure or death (HR 6.1, 95% CI 3.2-11.8). In an exploratory analysis, cluster determined treatment response (p=0.006). Conclusions regarding within-cluster treatment responses were limited by significant differences between select variables in the treated and untreated groups.

Conclusions

Cluster analysis identifies novel real-world subphenotypes of Group 3 PH patients with distinct clinical trajectories. Future studies may consider this methodological approach to identify subgroups of heterogeneous patients that may be responsive to existing pulmonary vasodilatory therapies.

Latent class analysis of chest CT abnormalities to define subphenotypes in patients with MPO-ANCA-positive microscopic polyangiitis

BACKGROUND

Patients with microscopic polyangiitis (MPA) and positive myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) may present with various abnormalities in chest computed tomography (CT). This study aimed to identify subphenotypes using latent class analysis (LCA) and to explore the relationship between the subphenotypes and clinical patterns, as well as compare the clinical characteristics of these subphenotypes in patients with MPO-ANCA-positive MPA (MPO-MPA).

METHODS

The study identified subphenotypes using LCA based on chest CT findings in 178 patients with MPO-MPA and pulmonary involvement from June 2014 to August 2022.

RESULTS

LCA identified 27 participants (15.2%) in class 1, 43 (24.1%) in class 2, 35 (19.7%) in class 3, and 73 (41.0%) in class 4. Class 1 was characterized by prominent inflammatory exudation, class 2 by fibrosis and architectural distortion, class 3 by predominantly bronchiectasis, and class 4 by lesions mixed with inflammation and fibrosis. Class 1 had the highest level of extrapulmonary disease activity, with 77.8% of patients experiencing diffuse alveolar hemorrhage. Class 2 had the lowest level of extrapulmonary disease activity, with 41.9% of patients showing usual interstitial pneumonia. Class 3 patients were more likely to have complications involving the ear, nose, and throat, as well as pulmonary infections before treatment, and they exhibited the best outcomes. The characteristics and outcomes of class 4 were intermediate among the four classes.

CONCLUSIONS

These findings suggest that bronchiectasis may represent a unique pattern of pulmonary involvement in MPO-MPA, highlighting the importance of screening for bronchiectasis in MPO-MPA and identifying optimal management strategies.

Longitudinal assessment of interstitial lung abnormalities on CT in patients with COPD using artificial intelligence-based segmentation: a prospective observational study

BACKGROUND

Interstitial lung abnormalities (ILAs) on CT may affect the clinical outcomes in patients with chronic obstructive pulmonary disease (COPD), but their quantification remains unestablished. This study examined whether artificial intelligence (AI)-based segmentation could be applied to identify ILAs using two COPD cohorts.

METHODS

ILAs were diagnosed visually based on the Fleischner Society definition. Using an AI-based method, ground-glass opacities, reticulations, and honeycombing were segmented, and their volumes were summed to obtain the percentage ratio of interstitial lung disease-associated volume to total lung volume (ILDvol%). The optimal ILDvol% threshold for ILA detection was determined in cross-sectional data of the discovery and validation cohorts. The 5-year longitudinal changes in ILDvol% were calculated in discovery cohort patients who underwent baseline and follow-up CT scans.

RESULTS

ILAs were found in 32 (14%) and 15 (10%) patients with COPD in the discovery (n = 234) and validation (n = 153) cohorts, respectively. ILDvol% was higher in patients with ILAs than in those without ILA in both cohorts. The optimal ILDvol% threshold in the discovery cohort was 1.203%, and good sensitivity and specificity (93.3% and 76.3%) were confirmed in the validation cohort. 124 patients took follow-up CT scan during 5 ± 1 years. 8 out of 124 patients (7%) developed ILAs. In a multivariable model, an increase in ILDvol% was associated with ILA development after adjusting for age, sex, BMI, and smoking exposure.

CONCLUSION

AI-based CT quantification of ILDvol% may be a reproducible method for identifying and monitoring ILAs in patients with COPD.

Prognostic implication of 1-year decline in diffusing capacity in newly diagnosed idiopathic pulmonary fibrosis

The progression of idiopathic pulmonary fibrosis (IPF) is assessed through serial monitoring of forced vital capacity (FVC). Currently, data regarding the clinical significance of longitudinal changes in diffusing capacity for carbon monoxide (DLCO) is lacking. We investigated the prognostic implications of a 1-year decline in DLCO in 319 patients newly diagnosed with IPF at a tertiary hospital between January 2010 and December 2020. Changes in FVC and DLCO over the first year after the initial diagnosis were reviewed; a decline in FVC ≥ 5% and DLCO ≥ 10% predicted were considered significant changes. During the first year after diagnosis, a significant decline in FVC and DLCO was observed in 101 (31.7%) and 64 (20.1%) patients, respectively. Multivariable analysis showed that a 1-year decline in FVC ≥ 5% predicted (aHR 2.74, 95% CI 1.88-4.00) and 1-year decline in DLCO ≥ 10% predicted (aHR 2.31, 95% CI 1.47-3.62) were independently associated with a higher risk of subsequent mortality. The prognostic impact of a decline in DLCO remained significant regardless of changes in FVC, presence of emphysema, or radiographic indications of pulmonary hypertension. Therefore, serial monitoring of DLCO should be recommended because it may offer additional prognostic information compared with monitoring of FVC alone.

Mortality surrogates in combined pulmonary fibrosis and emphysema

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) with coexistent emphysema, termed combined pulmonary fibrosis and emphysema (CPFE) may associate with reduced forced vital capacity (FVC) declines compared to non-CPFE IPF patients. We examined associations between mortality and functional measures of disease progression in two IPF cohorts.

METHODS

Visual emphysema presence (>0% emphysema) scored on computed tomography identified CPFE patients (CPFE/non-CPFE: derivation cohort n=317/n=183, replication cohort n=358/n=152), who were subgrouped using 10% or 15% visual emphysema thresholds, and an unsupervised machine-learning model considering emphysema and interstitial lung disease extents. Baseline characteristics, 1-year relative FVC and diffusing capacity of the lung for carbon monoxide (D LCO) decline (linear mixed-effects models), and their associations with mortality (multivariable Cox regression models) were compared across non-CPFE and CPFE subgroups.

RESULTS

In both IPF cohorts, CPFE patients with ≥10% emphysema had a greater smoking history and lower baseline D LCO compared to CPFE patients with <10% emphysema. Using multivariable Cox regression analyses in patients with ≥10% emphysema, 1-year D LCO decline showed stronger mortality associations than 1-year FVC decline. Results were maintained in patients suitable for therapeutic IPF trials and in subjects subgrouped by ≥15% emphysema and using unsupervised machine learning. Importantly, the unsupervised machine-learning approach identified CPFE patients in whom FVC decline did not associate strongly with mortality. In non-CPFE IPF patients, 1-year FVC declines ≥5% and ≥10% showed strong mortality associations.

CONCLUSION

When assessing disease progression in IPF, D LCO decline should be considered in patients with ≥10% emphysema and a ≥5% 1-year relative FVC decline threshold considered in non-CPFE IPF patients.