Association Between Interstitial Lung Abnormalities and All-Cause Mortality

3D Oxygen-Enhanced MRI at 3T MR System: Comparison With Thin-Section CT of Quantitative Capability for Pulmonary Functional Loss Assessment and Clinical Stage Classification of COPD in Smokers

BACKGROUND

Oxygen (O₂ )-enhanced MRI is mainly performed by a 2D sequence using 1.5T MR systems but trying to be obtained by a 3D sequence using a 3T MR system.

PURPOSE

To compare the capability of 3D O₂ -enhanced MRI and that of thin-section computed tomography (CT) for pulmonary functional loss assessment and clinical stage classification of chronic obstructive pulmonary disease (COPD) in smokers.

STUDY TYPE

Prospective study.

POPULATION

Fifty six smokers were included.

FIELD STRENGTH/ SEQUENCE

3T, 3D O₂ -enhanced MRIs were performed with a 3D T₁ -weighted fast field echo pulse sequence using the multiple flip angles.

ASSESSMENTS

Smokers were classified into four stages ("Without COPD," "Mild COPD," "Moderate COPD," "Severe or very severe COPD"). Maps of regional changes in T₁ values were generated from O₂ -enhanced MR data. Regions of interest (ROIs) were then placed over the lung on all slices and averaged to determine mean T₁ value change (ΔT₁ ). Quantitative CT used the percentage of low attenuation areas within the entire lung (LAA%).

STATISTICAL TESTS

ΔT₁ and LAA% were correlated with pulmonary functional parameters, and compared for four stages using Tukey's Honestly Significant Difference test. Discrimination analyses were performed and McNemar's test was used for a comparison of the accuracy of the indexes.

RESULTS

There were significantly higher correlations between ΔT₁ and pulmonary functional parameters (-0.83 ≤ r ≤ -0.71, P < 0.05) than between LAA% and the same pulmonary functional parameters (-0.76 ≤ r ≤ -0.69, P < 0.05). ΔT₁ and LAA% of the "Mild COPD" and "Moderate COPD" groups were significantly different from those of the "Severe or Very Severe COPD" group (P < 0.05). Discriminatory accuracy of ΔT₁ (62.5%) and ΔT1 with LAA% (67.9%) was significantly greater than that of LAA% (48.2%, P < 0.05).

DATA CONCLUSION

Compared with thin-section CT, 3D O₂ -enhanced MRI has a similar capability for pulmonary functional assessment but better potential for clinical stage classification in smokers.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 1.

Computerized Chest Imaging in the Diagnosis and Assessment of the Patient with Chronic Obstructive Pulmonary Disease

Computerized tomography in chronic obstructive pulmonary disease (COPD) has been the subject of intense interest in the research and clinical community. Methods have been developed to objectively detect and quantify processes affecting the lung parenchyma, airways and vasculature, as well as extrapulmonary manifestations of the noxious effects of chronic inhalational exposures, such as tobacco smoke. This article provides a brief overview of image-based advances in COPD research and then discusses how these advances have translated to clinical care, finishing with a brief description of a path forward for the convergence of research and care at the bedside.

Diffusion lung capacity for carbon monoxide correlates with HRCT findings in patients with diffuse parenchymal lung disease

Abstract

Diffusion lung capacity for carbon monoxide correlates with HRCT findings in patients with diffuse parenchymal lung disease.

Background

Diffuse parenchymal lung diseases (DPLDs) affect the alveolar epithelium, pulmonary capillary endothelium, basement membrane, and perivascular and perilymphatic tissues. High-resolution computed tomography (HRCT) of the chest is the gold standard modality for diagnosing DPLD. Pulmonary function tests usually show a restrictive defect in spirometry. Single breath diffusion lung capacity for carbon monoxide (DLCO-SB) technique is used to assess the diffuse parenchymal lung diseases, as there is thickening of the alveolar membrane and diminished total lung capacity due to interstitial processes with severe decline in the transfer factor. The aim of this work was to correlate between Warrick’s HRCT fibrosis score and DLCO-SB in DPLD and to assess the possibility of using DLCO as an only tool to follow up DPLD to avoid repeated radiation exposure of the patients in HRCT chest (decrease need for radiological follow-up) or vice versa.

Results

This work recruited 89 patients over a period of 10 months duration, 74.2% of them were females. The Warrick’s score, ground-glass opacity, irregular pleural margin, subpleural cyst, honeycombing, and septal and subpleural lines were represented as 96.6%, 70.8%, 55.1%, 49.4%, and 48.3% respectively in HRCT of DPLD. Warrick’s score and its subscores (severity score, extent score, alveolitis score, and fibrosis score) were associated with a highly significant decrease in different pulmonary function indices (FVC, FEV1, TLC, and DLCO) with P value 0.001. A highly significant correlation between DLCO grades and total score grades was found with P value 0.001, and 86.8% of the patients with severe DLCO affection showed severe degree of total fibrosis score.

Conclusions

Both DLCO-SB and HRCT fibrosis scores were significantly correlated. Lifelong follow-up of function and structure of the lung in DPLD is needed by HRCT and DLCO. In an attempt to minimize repeated radiation exposure and reduce cost, we suggest DLCO to be used alone for longer follow-up periods rather than HRCT chest.

Interstitial Lung Abnormalities: What Radiologists Should Know

Interstitial lung abnormalities (ILAs) are radiologic abnormalities found incidentally on chest CT that are potentially related to interstitial lung diseases. Several articles have reported that ILAs are associated with increased mortality, and they can show radiologic progression. With the increased recognition of ILAs on CT, the role of radiologists in reporting them is critical. This review aims to discuss the clinical significance and radiologic characteristics of ILAs to facilitate and enhance their management.

Perioperative risk factors in patients with idiopathic pulmonary fibrosis: a historical cohort study

PURPOSE

Perioperative complications of patients with idiopathic pulmonary fibrosis (IPF) are not well described. The aim of this study was to identify risk factors associated with adverse postoperative outcomes in IPF patients.

METHODS

We performed a single-centre historical cohort study of adult patients with IPF who underwent surgery between 2008 and 2018. We analyzed the prognostic utility of select perioperative factors for postoperative acute exacerbation of IPF (AE-IPF), acute respiratory worsening (ARW), pneumonia, and 30-day and one-year mortality using univariable and multivariable regression analyses. To adjust for multiple interactions, the false discovery rate (Q value) was utilized to appropriately adjust P values and a Q value < 0.05 was considered to be significant.

RESULTS

Two hundred and eighty-two patients were identified. After excluding emergency cases and bronchoscopies performed for active pneumonia, 14.2% of the cohort developed ARW that persisted > 24 hr after surgery, 5.0% had AE-IPF, and 9.2% were diagnosed with postoperative pneumonia within 30 days of surgery. The 30-day mortality was 6.0% and the one-year mortality was 14.9%. Preoperative home oxygen use (relative risk [RR], 2.70; 95% confidence interval [CI], 1.50 to 4.86; P < 0.001) and increasing surgical time (per 60 min) (RR, 1.03; 95% CI, 1.02 to 1.05; P < 0.001) were identified as independent risk factors for postoperative ARW.

CONCLUSIONS

In IPF patients, preoperative home oxygen requirement and increasing surgical time showed a strong relationship with postoperative ARW and may be useful markers for perioperative risk stratification. Facteurs de risque périopératoires des patients atteints de fibrose pulmonaire idiopathique : une étude de cohorte historique.

A Risk Prediction Model for Mortality Among Smokers in the COPDGene® Study

BACKGROUND

Risk factor identification is a proven strategy in advancing treatments and preventive therapy for many chronic conditions. Quantifying the impact of those risk factors on health outcomes can consolidate and focus efforts on individuals with specific high-risk profiles. Using multiple risk factors and longitudinal outcomes in 2 independent cohorts, we developed and validated a risk score model to predict mortality in current and former cigarette smokers.

METHODS

We obtained extensive data on current and former smokers from the COPD Genetic Epidemiology (COPDGene®) study at enrollment. Based on physician input and model goodness-of-fit measures, a subset of variables was selected to fit final Weibull survival models separately for men and women. Coefficients and predictors were translated into a point system, allowing for easy computation of mortality risk scores and probabilities. We then used the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS) cohort for external validation of our model.

RESULTS

Of 9867 COPDGene participants with standard baseline data, 17.6% died over 10 years of follow-up, and 9074 of these participants had the full set of baseline predictors (standard plus 6-minute walk distance and computed tomography variables) available for full model fits. The average age of participants in the cohort was 60 for both men and women, and the average predicted 10-year mortality risk was 18% for women and 25% for men. Model time-integrated area under the receiver operating characteristic curve statistics demonstrated good predictive model accuracy (0.797 average), validated in the external cohort (0.756 average). Risk of mortality was impacted most by 6-minute walk distance, forced expiratory volume in 1 second and age, for both men and women.

CONCLUSIONS

Current and former smokers exhibited a wide range of mortality risk over a 10- year period. Our models can identify higher risk individuals who can be targeted for interventions to reduce risk of mortality, for participants with or without chronic obstructive pulmonary disease (COPD) using current Global initiative for obstructive Lung Disease (GOLD) criteria.

Increased levels of HE4 (WFDC2) in systemic sclerosis: a novel biomarker reflecting interstitial lung disease severity?

Background:

Human epididymis protein 4 (HE4, also known as WFDC-2) has been implicated in fibrotic disorders pathobiology. We tested the hypothesis that HE4 may be used as a candidate biomarker for systemic sclerosis (SSc)-related interstitial lung disease (SSc-ILD).

Methods:

A total of 169 consecutive SSc patients and 169 age-and sex-matched healthy controls were enrolled and blood samples were collected. Pulmonary function tests (PFTs) and paired lavage was performed on 169 patients and 37 healthy controls. All patients were classified as having SSc-no ILD or SSc-ILD, based on high-resolution computed tomography (CT) scans of the chest, and a semiquantitative grade of ILD extent was evaluated through CT scans (grade 1, 0–25%; grade 2, 26–50%; grade 3, 51–75%; grade 4, 76–100%). Serum and bronchoalveolar lavage fluid (BALF) HE4 levels were measured by enzyme-linked immunosorbent assay.

Results:

Serum HE4 levels were higher in SSc patients [median (interquartile range), 139.4 (85.9–181.8) pmol/l] compared with healthy controls [39.5 (24.3–54.2) pmol/l, p < 0.001] and were higher in patients with SSc-ILD [172.1 (94.8–263.3) pmol/l] than in those with SSc-no ILD [97.4 (85.5–156.5) pmol/l, p < 0.001]. This observation was replicated in the BALF samples. Corresponding values were 510.8 (144.6–1013.8) pmol/l for SSc cohort, 754.4 (299–1060) pmol/l for SSc-ILD, 555.1 (203.7–776.2) pmol/l for SSc-no ILD, and 238.7 (97.7–397.6) pmol/l for controls. The semiquantitative grade of ILD on CT scan was significantly proportional to the HE4 levels and the lung function parameter (i.e., FVC) had a negative correlation with the HE4 levels.

Conclusion:

This is the first study to demonstrate the potential clinical utility of blood and BALF HE4 as a biomarker for SSc-ILD. Future prospective validation studies are warranted.

The Framingham Heart Study: Populational CT-based phenotyping in the lungs and mediastinum

The Framingham Heart Study (FHS) is one of the largest and established longitudinal populational cohorts. CT cohorts of the FHS since 2002 provided a unique opportunity to assess non-cardiac thoracic imaging findings. This review deals with image-based phenotyping studies from recent major publications regarding interstitial lung abnormalities (ILAs), pulmonary cysts, emphysema, pulmonary nodules, pleural plaques, normal spectrum of the thymus, and anterior mediastinal masses, concluding with the discussion of future directions of FHS CT cohorts studies in the era of radiomics and artificial intelligence.

Radiation-induced lung toxicity - cellular and molecular mechanisms of pathogenesis, management, and literature review

Lung, breast, and esophageal cancer represent three common malignancies with high incidence and mortality worldwide. The management of these tumors critically relies on radiotherapy as a major part of multi-modality care, and treatment-related toxicities, such as radiation-induced pneumonitis and/or lung fibrosis, are important dose limiting factors with direct impact on patient outcomes and quality of life. In this review, we summarize the current understanding of radiation-induced pneumonitis and pulmonary fibrosis, present predictive factors as well as recent diagnostic and therapeutic advances. Novel candidates for molecularly targeted approaches to prevent and/or treat radiation-induced pneumonitis and pulmonary fibrosis are discussed.

Machine Learning and Prediction of All-Cause Mortality in COPD

BACKGROUND

COPD is a leading cause of mortality.

RESEARCH QUESTION

We hypothesized that applying machine learning to clinical and quantitative CT imaging features would improve mortality prediction in COPD.

STUDY DESIGN AND METHODS

We selected 30 clinical, spirometric, and imaging features as inputs for a random survival forest. We used top features in a Cox regression to create a machine learning mortality prediction (MLMP) in COPD model and also assessed the performance of other statistical and machine learning models. We trained the models in subjects with moderate to severe COPD from a subset of subjects in Genetic Epidemiology of COPD (COPDGene) and tested prediction performance in the remainder of individuals with moderate to severe COPD in COPDGene and Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE). We compared our model with the BMI, airflow obstruction, dyspnea, exercise capacity (BODE) index; BODE modifications; and the age, dyspnea, and airflow obstruction index.

RESULTS

We included 2,632 participants from COPDGene and 1,268 participants from ECLIPSE. The top predictors of mortality were 6-min walk distance, FEV1 % predicted, and age. The top imaging predictor was pulmonary artery-to-aorta ratio. The MLMP-COPD model resulted in a C index ≥ 0.7 in both COPDGene and ECLIPSE (6.4- and 7.2-year median follow-ups, respectively), significantly better than all tested mortality indexes (P < .05). The MLMP-COPD model had fewer predictors but similar performance to that of other models. The group with the highest BODE scores (7-10) had 64% mortality, whereas the highest mortality group defined by the MLMP-COPD model had 77% mortality (P = .012).

INTERPRETATION

An MLMP-COPD model outperformed four existing models for predicting all-cause mortality across two COPD cohorts. Performance of machine learning was similar to that of traditional statistical methods. The model is available online at: https://cdnm.shinyapps.io/cgmortalityapp/.

Interstitial Lung Disease in Relatives of Patients with Pulmonary Fibrosis

Rationale: Although relatives of patients with familial pulmonary fibrosis (FPF) are at an increased risk for interstitial lung disease (ILD), the risk among relatives of sporadic idiopathic pulmonary fibrosis (IPF) is not known.Objectives: To identify the prevalence of interstitial lung abnormalities (ILA) and ILD among relatives of patients with FPF and sporadic IPF.Methods: Undiagnosed first-degree relatives of patients with pulmonary fibrosis (PF) consented to participate in a screening study that included the completion of questionnaires, pulmonary function testing, chest computed tomography, a blood sample collection for immunophenotyping, telomere length assessments, and genetic testing.Measurements and Main Results: Of the 105 relatives in the study, 33 (31%) had ILA, whereas 72 (69%) were either indeterminate or had no ILA. Of the 33 relatives with ILA, 19 (58%) had further evidence for ILD (defined by the combination of imaging findings and pulmonary function testing decrements). There was no evidence in multivariable analyses that the prevalence of either ILA or ILD differed between the 46 relatives with FPF and the 59 relatives with sporadic IPF. Relatives with decrements in either total lung or diffusion capacity had a greater than 9-fold increase in their odds of having ILA (odds ratio, 9.6; 95% confidence interval, 3.1-29.8; P < 0.001).Conclusions: An undiagnosed form of ILD may be present in greater than 1 in 6 older first-degree relatives of patients with PF. First-degree relatives of patients with both familial and sporadic IPF appear to be at similar risk. Our findings suggest that screening for PF in relatives might be warranted.

Development and Progression of Radiologic Abnormalities in Individuals at Risk for Familial Interstitial Lung Disease

Rationale: The preclinical natural history of progressive lung fibrosis is poorly understood.Objectives: Our goals were to identify risk factors for interstitial lung abnormalities (ILA) on high-resolution computed tomography (HRCT) scans and to determine progression toward clinical interstitial lung disease (ILD) among subjects in a longitudinal cohort of self-reported unaffected first-degree relatives of patients with familial interstitial pneumonia.Methods: Enrollment evaluation included a health history and exposure questionnaire and HRCT scans, which were categorized by visual assessment as no ILA, early/mild ILA, or extensive ILA. The study endpoint was met when ILA were extensive or when ILD was diagnosed clinically. Among subjects with adequate study time to complete 5-year follow-up HRCT, the proportion with ILD events (endpoint met or radiographic ILA progression) was calculated.Measurements and Main Results: Among 336 subjects, the mean age was 53.1 (SD, 9.9) years. Those with ILA (early/mild [n = 74] or extensive [n = 3]) were older, were more likely to be ever smokers, had shorter peripheral blood mononuclear cell telomeres, and were more likely to carry the MUC5B risk allele. Self-reported occupational or environmental exposures, including aluminum smelting, lead, birds, and mold, were independently associated with ILA. Among 129 subjects with sufficient study time, 25 (19.4%) had an ILD event by 5 years after enrollment; of these, 12 met the study endpoint and another 13 had radiologic progression of ILA. ILD events were more common among those with early/mild ILA at enrollment (63.3% vs. 6.1%; P < 0.0001).Conclusions: Rare and common environmental exposures are independent risk factors for radiologic abnormalities. In 5 years, progression of ILA occurred in most individuals with early ILA detected at enrollment.

Interstitial lung abnormalities detected incidentally on CT: a Position Paper from the Fleischner Society

The term interstitial lung abnormalities refers to specific CT findings that are potentially compatible with interstitial lung disease in patients without clinical suspicion of the disease. Interstitial lung abnormalities are increasingly recognised as a common feature on CT of the lung in older individuals, occurring in 4-9% of smokers and 2-7% of non-smokers. Identification of interstitial lung abnormalities will increase with implementation of lung cancer screening, along with increased use of CT for other diagnostic purposes. These abnormalities are associated with radiological progression, increased mortality, and the risk of complications from medical interventions, such as chemotherapy and surgery. Management requires distinguishing interstitial lung abnormalities that represent clinically significant interstitial lung disease from those that are subclinical. In particular, it is important to identify the subpleural fibrotic subtype, which is more likely to progress and to be associated with mortality. This multidisciplinary Position Paper by the Fleischner Society addresses important issues regarding interstitial lung abnormalities, including standardisation of the definition and terminology; predisposing risk factors; clinical outcomes; options for initial evaluation, monitoring, and management; the role of quantitative evaluation; and future research needs.

Interstitial Lung Abnormalities and the Clinical Course in Patients With COPD

BACKGROUND

The presence and progression of interstitial lung abnormalities (ILAs) is known to be associated with a decline of lung function and increased risk of mortality.

RESEARCH QUESTION

We aimed to elucidate the clinical course according to ILAs in patients with COPD.

STUDY DESIGN AND METHODS

A retrospective study was conducted between January 2013 and December 2018 of COPD patients who underwent chest CT imaging and longitudinal pulmonary function tests. We evaluated radiologic findings, history of acute exacerbations of COPD, and lung function changes during the longitudinal follow-up.

RESULTS

Of 363 patients with COPD, 44 and 103 patients had equivocal and definite ILAs, respectively. Patients with ILAs were significantly older and had lower FEV₁ and FVC than patients without ILAs. During the mean follow-up period of 5.2 years, ILAs were associated significantly with the annual incidence of moderate to severe acute exacerbation of COPD (β ± SD, 0.38 ± 0.12; P = .002) and with the risk of frequent exacerbation (adjusted OR, 2.03; P = .045). Patients with progressive ILAs showed a significantly higher rate of annual decline in FEV₁ and FVC than those showing no change in, or improved, ILAs.

INTERPRETATION

ILAs were associated significantly with moderate to severe acute exacerbation in patients with COPD, and the progression of ILAs was associated with an accelerated decline in lung function.

Circulating microRNA Signature Associated to Interstitial Lung Abnormalities in Respiratory Asymptomatic Subjects

Interstitial lung abnormalities (ILA) are observed in around 9% of older respiratory asymptomatic subjects, mainly smokers. Evidence suggests that ILA may precede the development of interstitial lung diseases and may evolve to progressive fibrosis. Identifying biomarkers of this subclinical status is relevant for early diagnosis and to predict outcome. We aimed to identify circulating microRNAs (miRNAs) associated to ILA in a cohort of respiratory asymptomatic subjects older than 60 years. We identified 81 subjects with ILA from our Lung-Aging Program in Mexico City (n = 826). We randomly selected 112 subjects without ILA (Ctrl) from the same cohort. Using polymerase chain reaction PCR-Array technology (24 ILA and 24 Ctrl, screening cohort) and reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR) (57 ILA and 88 Ctr, independent validation cohort) we identified seven up-regulated miRNAs in serum of ILA compared to Ctrl (miR-193a-5p, p < 0.0001; miR-502-3p, p < 0.0001; miR-200c-3p, p = 0.003; miR-16-5p, p = 0.003; miR-21-5p, p = 0.002; miR-126-3p, p = 0.004 and miR-34a-5p, p < 0.005). Pathways regulated by these miRNAs include transforming growth factor beta (TGF-β), Wnt, mammalian target of rapamycin (mTOR), Insulin, mitogen-activated protein kinase (MAPK) signaling, and senescence. Receiver operator characteristic (ROC) curve analysis indicated that miR-193a-5p (area under the curve AUC: 0.75) and miR-502-3p (AUC 0.71) have acceptable diagnostic value. This is the first identification of circulating miRNAs associated to ILA in respiratory asymptomatic subjects, providing potential non-invasive biomarkers and molecular targets to better understand the pathogenic mechanisms associated to ILA.

Shedding light on developmental drugs for idiopathic pulmonary fibrosis

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is an age-related disease of unknown cause. The disease is characterized by relentless scarring of the lung parenchyma resulting in respiratory failure and death. Two antifibrotic drugs (pirfenidone and nintedanib) are approved for the treatment of IPF worldwide, but they do not offer a cure and are associated with tolerability issues. Owing to its high unmet medical need, IPF is an area of dynamic research activity.

AREAS COVERED

There is a growing portfolio of novel therapies that target different pathways involved in the complex pathogenesis of IPF. In this review, we discuss the mechanisms of action and available data for compounds in the most advanced stages of clinical development. We searched PubMed for articles on this topic published from 1 January 2000, to 6 June 2020.

EXPERT OPINION

The approval of pirfenidone and nintedanib has fueled IPF drug discovery and development. New drugs are likely to reach the clinic in the near future. However, numerous challenges remain; the lack of animal models that reproduce the complexity of human disease and the poor translation of preclinical and early-phase positive effects to late stage clinical trials must be tackled.

Increased Airway Wall Thickness in Interstitial Lung Abnormalities and Idiopathic Pulmonary Fibrosis

RATIONALE

There is increasing evidence that aberrant processes occurring in the airways may precede the development of idiopathic pulmonary fibrosis (IPF); however, there has been no prior confirmatory data derived from imaging studies.

OBJECTIVES

To assess quantitative measures of airway wall thickness (AWT) in populations characterized for interstitial lung abnormalities (ILA) and for IPF.

METHODS

Computed tomographic imaging of the chest and measures of AWT were available for 6,073, 615, 1,167, and 38 participants from COPDGene (Genetic Epidemiology of COPD study), ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints study), and the Framingham Heart Study (FHS) and in patients with IPF from the Brigham and Women's Hospital Herlihy Registry, respectively. To evaluate these associations, we used multivariable linear regression to compare a standardized measure of AWT (the square root of AWT for airways with an internal perimeter of 10 mm [Pi10]) and characterizations of ILA and IPF by computed tomographic imaging of the chest.

RESULTS

In COPDGene, ECLIPSE, and FHS, research participants with ILA had increased measures of Pi10 compared with those without ILA. Patients with IPF had mean measures of Pi10 that were even greater than those noted in research participants with ILA. After adjustment for important covariates (e.g., age, sex, race, body mass index, smoking behavior, and chronic obstructive pulmonary disease severity when appropriate), research participants with ILA had increased measures of Pi10 compared with those without ILA (0.03 mm in COPDGene, 95% confidence interval [CI], 0.02-0.03; P < 0.001; 0.02 mm in ECLIPSE, 95% CI, 0.005-0.04; P = 0.01; 0.07 mm in FHS, 95% CI, 0.01-0.1; P = 0.01). Compared with COPDGene participants without ILA older than 60 years of age, patients with IPF were also noted to have increased measures of Pi10 (2.0 mm, 95% CI, 2.0-2.1; P < 0.001). Among research participants with ILA, increases in Pi10 were correlated with reductions in lung volumes in some but not all populations.

CONCLUSIONS

These results demonstrate that measurable increases in AWT are consistently noted in research participants with ILA and in patients with IPF. These findings suggest that abnormalities of the airways may play a role in, or be correlated with, early pathogenesis of pulmonary fibrosis.

Cigarette Smoke Exposure and Radiographic Pulmonary Vascular Morphology in the Framingham Heart Study

Rationale: Cigarette smoke exposure is a risk factor for many lung diseases, and histologic studies suggest that tobacco-related vasoconstriction and vessel loss plays a role in the development of emphysema. However, it remains unclear how tobacco affects the pulmonary vasculature in general populations with a typical range of tobacco exposure, and whether these changes are detectable by radiographic methods. Objectives: To determine whether tobacco exposure in a generally healthy population manifests as lower pulmonary blood vessel volumes and vascular pruning on imaging. Methods: A total of 2,410 Framingham Heart Study participants with demographic data and smoking history underwent volumetric whole-lung computed tomography from 2008 to 2011. Automated algorithms calculated the total blood volume of all intrapulmonary vessels (TBV), smaller peripheral vessels (defined as cross-sectional area <5 mm² [BV5]), and the relative fraction of small vessels (BV5/TBV). Tobacco exposure was assessed as smoking status, cumulative pack-years, and second-hand exposure. We constructed multivariable linear regression models to evaluate associations of cigarette exposure and pulmonary blood vessel volume measures, adjusting for demographic covariates, including age, sex, height, weight, education, occupation, and median neighborhood income. Results: All metrics of tobacco exposure (including smoking status, pack-years, and second-hand exposure) were consistently associated with higher absolute pulmonary blood vessel volume, higher small vessel volume, and/or higher small vessel fraction. For example, ever-smokers had a 4.6 ml higher TBV (95% confidence interval [CI] = 2.9-6.3, P < 0.001), 2.1 ml higher BV5 (95% CI = 1.3-2.9, P < 0.001), and 0.28 percentage-point-higher BV5/TBV (95% CI = 0.03-0.52, P = 0.03) compared with never-smokers. These associations remained significant after adjustment for percent predicted forced expiratory volume in 1 second, cardiovascular comorbidities, and did not differ based on presence or absence of airflow obstruction. Conclusions: Using computed tomographic imaging, we found that cigarette exposure was associated with higher pulmonary blood vessel volumes, especially in the smaller peripheral vessels. Although, histologically, tobacco-related vasculopathy is characterized by vessel narrowing and loss, our results suggest that radiographic vascular pruning may not be a surrogate of these pathologic changes.

Small airways pathology in idiopathic pulmonary fibrosis: a retrospective cohort study

BACKGROUND

The observation that patients with idiopathic pulmonary fibrosis (IPF) can have higher than normal expiratory flow rates at low lung volumes led to the conclusion that the airways are spared in IPF. This study aimed to re-examine the hypothesis that airways are spared in IPF using a multiresolution imaging protocol that combines multidetector CT (MDCT), with micro-CT and histology.

METHODS

This was a retrospective cohort study comparing explanted lungs from patients with severe IPF treated by lung transplantation with a cohort of unused donor (control) lungs. The donor control lungs had no known lung disease, comorbidities, or structural lung injury, and were deemed appropriate for transplantation on review of the clinical files. The diagnosis of IPF in the lungs from patients was established by a multidisciplinary consensus committee according to existing guidelines, and was confirmed by video-assisted thoracic surgical biopsy or by pathological examination of the contralateral lung. The control and IPF groups were matched for age, sex, height, and bodyweight. Samples of lung tissue were compared using the multiresolution imaging approach: a cascade of clinical MDCT, micro-CT, and histological imaging. We did two experiments: in experiment 1, all the lungs were randomly sampled; in experiment 2, samples were selected from regions of minimal and established fibrosis. The patients and donors were recruited from the Katholieke Universiteit Leuven (Leuven, Belgium) and the University of Pennsylvania Hospital (Philadelphia, PA, USA). The study took place at the Katholieke Universiteit Leuven, and the University of British Columbia (Vancouver, BC, Canada).

FINDINGS

Between Oct 5, 2009, and July 22, 2016, explanted lungs from patients with severe IPF (n=11), were compared with a cohort of unused donor (control) lungs (n=10), providing 240 samples of lung tissue for comparison using the multiresolution imaging approach. The MDCT specimen scans show that the number of visible airways located between the ninth generation (control 69 [SD 22] versus patients with IPF 105 [33], p=0·0023) and 14th generation (control 9 [6] versus patients with IPF 49 [28], p<0·0001) of airway branching are increased in patients with IPF, which we show by micro-CT is due to thickening of their walls and distortion of their lumens. The micro-CT analysis showed that compared with healthy (control) lung anatomy (mean 5·6 terminal bronchioles per mL [SD 1·6]), minimal fibrosis in IPF tissue was associated with a 57% loss of the terminal bronchioles (mean 2·4 terminal bronchioles per mL [SD 1·0]; p<0·0001), the appearance of fibroblastic foci, and infiltration of the tissue by inflammatory immune cells capable of forming lymphoid follicles. Established fibrosis in IPF tissue had a similar reduction (66%) in the number of terminal bronchioles (mean 1·9 terminal bronchioles per mL [SD 1·4]; p<0·0001) and was dominated by increased airspace size, Ashcroft fibrosis score, and volume fractions of tissue and collagen.

INTERPRETATION

Small airways disease is a feature of IPF, with significant loss of terminal bronchioles occuring within regions of minimal fibrosis. On the basis of these findings, we postulate that the small airways could become a potential therapeutic target in IPF.

FUNDING

Katholieke Universiteit Leuven, US National Institutes of Health, BC Lung Association, and Genentech.

Long-term use of combined conventional medicine and Chinese herbal medicine decreases the mortality risk of patients with lung cancer

BACKGROUND

We explored the effect of Chinese herbal medicine (CHM) on the long-term survival of lung cancer patients and hazard ratio (HR) and to analyse CHM herbs and formulas for lung cancer treatment.

METHODS

We conducted a retrospective cohort study on diagnosed lung cancer patients in 2003-2016 from Taipei and Dalin Tzu Chi General Hospital Cancer Registry Database and from outpatient database from Chinese Medicine and Conventional Medicine Department. We categorised the patients into CHM user and CHM nonuser groups according to the CHM consumption time. After passing the proportional hazard assumption, we used the Cox PH model to calculate the groups' survival hazard ratio (HR) and examine the statistical difference and effect of CHM on lung cancer survival.

RESULTS

We classified 2557 lung cancer patients into 1643 CHM nonusers and 228 CHM users. The CHM users had lower mortality than the CHM nonusers. With the multivariable Cox model, we observed that the CHM use was associated with 35% lower risk of mortality (adjusted HR: 0.65; 95% confidence interval: 0.51-0.76). Continuous CHM use of >180 days may further lessen the mortality risk by 64%. Finally, eight herbs and two formulas could significantly lower the mortality. After pairing the eight herbs for analysis, seven combinations could reduce the mortality better than only using one herb.

CONCLUSION

CHM users had significantly lower mortality than CHM nonusers. The longer the CHM use, the more the mortality HR declined. Glehnia littoralisF. Schmidt ex Miq., Polyporus umbellatus(Pers.) Fries and Trichosanthes kirilowii Maxim. possess a highly substantial anticancer activity compared with other herbs.

Traction Bronchiectasis/Bronchiolectasis is Associated with Interstitial Lung Abnormality Mortality

PURPOSE

To investigate if the presence and severity of traction bronchiectasis/bronchiolectasis are associated with poorer survival in subjects with ILA.

METHOD

The study included 3,594 subjects (378 subjects with ILA and 3,216 subjects without ILA) in AGES-Reykjavik Study. Chest CT scans of 378 subjects with ILA were evaluated for traction bronchiectasis/bronchiolectasis, defined as dilatation of bronchi/bronchioles within areas demonstrating ILA. Traction bronchiectasis/bronchiolectasis Index (TBI) was assigned as: TBI = 0, ILA without traction bronchiectasis/bronchiolectasis: TBI = 1, ILA with bronchiolectasis but without bronchiectasis or architectural distortion: TBI = 2, ILA with mild to moderate traction bronchiectasis: TBI = 3, ILA and severe traction bronchiectasis and/or honeycombing. Overall survival (OS) was compared among the subjects in different TBI groups and those without ILA.

RESULTS

The median OS was 12.93 years (95%CI; 12.67 - 13.43) in the subjects without ILA; 11.95 years (10.03 - not reached) in TBI-0 group; 8.52 years (7.57 - 9.30) in TBI-1 group; 7.63 years (6.09 - 9.10) in TBI-2 group; 5.40 years (1.85 - 5.98) in TBI-3 group. The multivariable Cox models demonstrated significantly shorter OS of TBI-1, TBI-2, and TBI-3 groups compared to subjects without ILA (P < 0.0001), whereas TBI-0 group had no significant OS difference compared to subjects without ILA, after adjusting for age, sex, and smoking status.

CONCLUSIONS

The presence and severity of traction bronchiectasis/bronchiolectasis are associated with shorter survival. The traction bronchiectasis/bronchiolectasis is an important contributor to increased mortality among subjects with ILA.

Baseline Characteristics and Progression of a Spectrum of Interstitial Lung Abnormalities and Disease in Rheumatoid Arthritis

BACKGROUND

Interstitial lung abnormalities (ILA) and interstitial lung disease (ILD) are seen in up to 60% of individuals with rheumatoid arthritis (RA), some of which will progress to have a significant impact on morbidity and mortality rates. Better characterization of progressive interstitial changes and identification of risk factors that are associated with progression may enable earlier intervention and improved outcomes.

RESEARCH QUESTION

What are baseline characteristics associated with RA-ILD progression?

STUDY DESIGN AND METHODS

We performed a retrospective study in which all clinically indicated CT chest scans in adult individuals with RA from 2014 to 2016 were evaluated for interstitial changes, and the data were further subdivided into ILA and ILD based on clinical record review. Progression was determined visually and subsequently semiquantified.

RESULTS

Those individuals with a spectrum of interstitial changes (64 of 293) were older male smokers and less likely to be receiving biologics/small molecule disease-modifying antirheumatic drugs. Of 44% of the individuals with ILA, 46% had had chest CT scans performed for nonpulmonary indications. Of the 56 individuals with ILA/ILD with sequential CT scans, 38% had evidence of radiologic progression over 4.4 years; 29% of of individuals with ILA progressed. Risk factors for progressive ILA/ILD included a subpleural distribution and higher baseline involvement.

INTERPRETATION

Of 293 individuals with RA with clinically indicated CT scans, interstitial changes were observed in 22%, one-half of whom had had a respiratory complaint at the time of imaging; radiologic progression was seen in 38%. Of individuals with progressive ILA, one-half had had baseline CT scans performed for nonpulmonary indications. Subpleural distribution and higher baseline ILA/ILD extent were risk factors associated with progression. Prospective longitudinal studies of RA-ILA are necessary.

Smaller Left Ventricle Size at Noncontrast CT Is Associated with Lower Mortality in COPDGene Participants

Background Smokers with chronic obstructive pulmonary disease (COPD) have smaller left ventricles (LVs) due to reduced preload. Skeletal muscle wasting is also common in COPD, but less is known about its contribution to LV size. Purpose To explore the relationships between CT metrics of emphysema, venous vascular volume, and sarcopenia with the LV epicardial volume (LV_EV) (myocardium and chamber) estimated from chest CT images in participants with COPD and then to determine the clinical relevance of the LV_EV in multivariable models, including sex and anthropomorphic metrics. Materials and Methods The COPDGene study (ClinicalTrials.gov identifier: NCT00608764) is an ongoing prospective longitudinal observational investigation that began in 2006. LV_EV, distal pulmonary venous blood volume for vessels smaller than 5 mm² in cross section (BV5), CT emphysema, and pectoralis muscle area were retrospectively extracted from 3318 nongated, unenhanced COPDGene CT scans. Multivariable linear and Cox regression models were used to explore the association between emphysema, venous BV5, pectoralis muscle area, and LV_EV as well as the association of LV_EV with health status using the St George's Respiratory Questionnaire, 6-minute walk distance, and all-cause mortality. Results The median age of the cohort was 64 years (interquartile range, 57-70 years). Of the 2423 participants, 1806 were men and 617 were African American. The median LV_EV between Global Initiative for Chronic Obstructive Lung Disease (GOLD) 1 and GOLD 4 COPD was reduced by 13.9% in women and 17.7% in men (P < .001 for both). In fully adjusted models, higher emphysema percentage (β = -4.2; 95% confidence interval [CI]: -5.0, -3.4; P < .001), venous BV5 (β = 7.0; 95% CI: 5.7, 8.2; P < .001), and pectoralis muscle area (β = 2.7; 95% CI: 1.2, 4.1; P < .001) were independently associated with reduced LV_EV. Reductions in LV_EV were associated with improved health status (β = 0.3; 95% CI: 0.1, 0.4) and 6-minute walk distance (β = -12.2; 95% CI: -15.2, -9.3). These effects were greater in women than in men. The effect of reduced LV_EV on mortality (hazard ratio: 1.07; 95% CI: 1.05, 1.09) did not vary by sex. Conclusion In women more than men with chronic obstructive pulmonary disease, a reduction in the estimated left ventricle epicardial volume correlated with a loss of pulmonary venous vasculature, greater pectoralis muscle sarcopenia, and lower all-cause mortality. © RSNA, 2020 Online supplemental material is available for this article.

Biochemical and imaging parameters in acid sphingomyelinase deficiency: Potential utility as biomarkers

Acid Sphingomyelinase Deficiency (ASMD), or Niemann-Pick type A/B disease, is a rare lipid storage disorder leading to accumulation of sphingomyelin and its precursors primarily in macrophages. The disease has a broad phenotypic spectrum ranging from a fatal infantile form with severe neurological involvement (the infantile neurovisceral type) to a primarily visceral form with different degrees of pulmonary, liver, spleen and skeletal involvement (the chronic visceral type). With the upcoming possibility of treatment with enzyme replacement therapy, the need for biomarkers that predict or reflect disease progression has increased. Biomarkers should be validated for their use as surrogate markers of clinically relevant endpoints. In this review, clinically important endpoints as well as biochemical and imaging markers of ASMD are discussed and potential new biomarkers are identified. We suggest as the most promising biomarkers that may function as surrogate endpoints in the future: diffusion capacity measured by spirometry, spleen volume, platelet count, low-density lipoprotein cholesterol, liver fibrosis measured with a fibroscan, lysosphingomyelin and walked distance in six minutes. Currently, no biomarkers have been validated. Several plasma markers of lipid-laden cells, fibrosis or inflammation are of high potential as biomarkers and deserve further study. Based upon current guidelines for biomarkers, recommendations for the validation process are provided.

Clinical characteristics of COVID-19 infection in chronic obstructive pulmonary disease: a multicenter, retrospective, observational study

Background

Coronavirus disease 2019 (COVID-19) has been a global pandemic disease, with more than 4 million cases and nearly 300,000 deaths. Little is known about COVID-19 in patients with chronic obstructive pulmonary disease (COPD). We aimed to evaluate the influence of preexisting COPD on the progress and outcomes of COVID-19.

Methods

This was a multicenter, retrospective, observational study. We enrolled 1,048 patients aged 40 years and above, including 50 patients with COPD and 998 patients without COPD, and with COVID-19 confirmed via high-throughput sequencing or real-time reverse transcription-polymerase chain reaction, between December 11, 2019 and February 20, 2020. We collected data of demographics, pathologic test results, radiologic imaging, and treatments. The primary outcomes were composite endpoints determined by admission to an intensive care unit, the use of mechanical ventilation, or death.

Results

Compared with patients who had COVID-19 but not COPD, those with COPD had higher rates of fatigue (56.0% vs. 40.2%), dyspnea (66.0% vs. 26.3%), diarrhea (16.0% vs. 3.6%), and unconsciousness (8.0% vs. 1.7%) and a significantly higher proportion of increased activated partial thromboplastin time (23.5% vs. 5.2%) and D-dimer (65.9% vs. 29.3%), as well as ground-glass opacities (77.6% vs. 60.3%), local patchy shadowing (61.2% vs. 41.4%), and interstitial abnormalities (51.0% vs. 19.8%) on chest computed tomography. Patients with COPD were more likely to develop bacterial or fungal coinfection (20.0% vs. 5.9%), acute respiratory distress syndrome (ARDS) (20.0% vs. 7.3%), septic shock (14.0% vs. 2.3%), or acute renal failure (12.0% vs. 1.3%). Patients with COPD and COVID-19 had a higher risk of reaching the composite endpoints [hazard ratio (HR): 2.17, 95% confidence interval (CI): 1.40–3.38; P=0.001] or death (HR: 2.28, 95% CI: 1.15–4.51; P=0.019), after adjustment.

Conclusions

In this study, patients with COPD who developed COVID-19 showed a higher risk of admission to the intensive care unit, mechanical ventilation, or death.

Fibrotic Lung Disease at CT Predicts Adverse Outcomes in Patients Undergoing Transcatheter Aortic Valve Replacement

Purpose

To evaluate the relationship between CT findings of diffuse lung disease and post-transcatheter aortic valve replacement (TAVR) outcomes.

Materials and Methods

Retrospective review of pre-TAVR CT scans obtained during 2012-2017 was conducted. Emphysema, reticulation, and honeycombing were separately scored using a five-point scale and applied to 10 images per examination. The fibrosis score was the sum of reticulation and honeycombing scores. Lung diseases were also assessed as dichotomous variables (zero vs nonzero scores). The two outcomes evaluated were death and the composite of death and readmission.

Results

The study included 373 patients with median age of 84 years (age range, 51-98 years; interquartile range, 79-88 years) and median follow-up of 333 days. Fibrosis and emphysema were present in 66 (17.7%) and 95 (25.5%) patients, respectively. Fibrosis as a dichotomous variable was independently associated with the composite of death and readmission (hazard ratio [HR], 1.54; P = .030). In those without known chronic lung disease (CLD) (HR, 3.09; P = .024) and those without airway obstruction, defined by a ratio of forced expiratory volume in 1 second to the forced vital capacity greater than or equal to 70% (HR, 1.67, P = .039), CT evidence of fibrosis was a powerful predictor of adverse events. Neither emphysema score nor emphysema as a dichotomous variable was an independent predictor of outcome.

Conclusion

The presence of fibrosis on baseline CT scans was an independent predictor of adverse events after TAVR. In particular, fibrosis had improved predictive value in both patients without known CLD and patients without airway obstruction.Supplemental material is available for this article.© RSNA, 2020.

New Era of Management Concept on Pulmonary Fibrosis with Revisiting Framework of Interstitial Lung Diseases

The disease concept of interstitial lung disease with idiopathic pulmonary fibrosis at its core has been relied on for many years depending on morphological classification. The separation of non-specific interstitial pneumonia with a relatively good prognosis from usual interstitial pneumonia is also based on the perception that morphology enables predict the prognosis. Beginning with dust-exposed lungs, initially, interstitial pneumonia is classified by anatomical pathology. Diagnostic imaging has dramatically improved the diagnostic technology for surviving patients through the introduction of high-resolution computed tomography scan. And now, with the introduction of therapeutics, the direction of diagnosis is turning. It can be broadly classified into to make known the importance of early diagnosis, and to understand the importance of predicting the speed of progression/deterioration of pathological conditions. For this reason, the insight of “early lesions” has been discussed. There are reports that the presence or absence of interstitial lung abnormalities affects the prognosis. Searching for a biomarker is another prognostic indicator search. However, as is the case with many chronic diseases, pathological conditions that progress linearly are extremely rare. Rather, it progresses while changing in response to environmental factors. In interstitial lung disease, deterioration of respiratory functions most closely reflect prognosis. Treatment is determined by combining dynamic indicators as faithful indicators of restrictive impairments. Reconsidering the history being classified under the disease concept, the need to reorganize treatment targets based on common pathological phenotype is under discussed. What is the disease concept? That aspect changes with the discussion of improving prognosis.

[Idiopathic pulmonary fibrosis-epidemiology, causes, and clinical course]

Idiopathic pulmonary fibrosis (IPF) plays a special role within the group of interstitial lung diseases (ILDs) due to its inexorable progression and its specific medical treatment. With a median survival of only 2-3 years from the time of diagnosis, the prognosis is worse than many carcinomas.In contrast to other ILDs, IPF does not respond to anti-inflammatory treatment with corticosteroids but rather demands a specific medical therapy. Even though this cannot cure the disease, it can prolong survival. Lung transplantation is the only cure for progressive lung fibrosis. The clinical course is individual and difficult to predict. Acute exacerbations accelerate the clinical course and lead to high mortality.The underlying pathomechanisms of IPF, with its complex immunological and inflammatory processes and external impacts, have been the focus of recent research. Lifestyle and environmental influences are held responsible for much of its natural history. Smoking, pneumotoxic medications, and inhalation of dusts are well-known risk factors. Likewise, genetic and hereditary factors play a crucial role.This short review focuses on the peculiarities of IPF within the group of ILDs, especially in relation to its underlying mechanisms and clinical progression.

Increased respiratory morbidity in individuals with interstitial lung abnormalities

Background

Interstitial lung abnormalities (ILA) are common in participants of lung cancer screening trials and broad population-based cohorts. They are associated with increased mortality, but less is known about disease specific morbidity and healthcare utilisation in individuals with ILA.

Methods

We included all participants from the screening arm of the Danish Lung Cancer Screening Trial with available baseline CT scan data (n = 1990) in this cohort study. The baseline scan was scored for the presence of ILA and patients were followed for up to 12 years. Data about all hospital admissions, primary healthcare visits and medicine prescriptions were collected from the Danish National Health Registries and used to determine the participants’ disease specific morbidity and healthcare utilisation using Cox proportional hazards models.

Results

The 332 (16.7%) participants with ILA were more likely to be diagnosed with one of several respiratory diseases, including interstitial lung disease (HR: 4.9, 95% CI: 1.8–13.3, p = 0.008), COPD (HR: 1.7, 95% CI: 1.2–2.3, p = 0.01), pneumonia (HR: 2.0, 95% CI: 1.4–2.7, p <  0.001), lung cancer (HR: 2.7, 95% CI: 1.8–4.0, p <  0.001) and respiratory failure (HR: 1.8, 95% CI: 1.1–3.0, p = 0.03) compared with participants without ILA. These findings were confirmed by increased hospital admission rates with these diagnoses and more frequent prescriptions for inhalation medicine and antibiotics in participants with ILA.

Conclusions

Individuals with ILA are more likely to receive a diagnosis and treatment for several respiratory diseases, including interstitial lung disease, COPD, pneumonia, lung cancer and respiratory failure during long-term follow-up.

Patient and Physician Perspectives on Systemic Sclerosis-Associated Interstitial Lung Disease

Systemic sclerosis-associated interstitial lung disease is challenging to diagnose and treat. Patients and physicians can perceive the disease differently and have different views on its management. Communication issues between them can lead to suboptimal disease management. Despite a clear need for improvement in the speed and accuracy of the diagnostic workup, the heterogeneity of clinical symptoms renders the process long and challenging. When considering treatment options, physicians may be more focused on the evidence supporting a particular treatment or on a patient's pulmonary function test results, as opposed to the realities of the patient's difficulties with symptoms or the psychosocial effects of systemic sclerosis-associated interstitial lung disease. Disease management plans should be determined by the patient's own preferences and goals as well as the objective clinical situation. Health care providers must consider their patients as partners on a journey in which treatment decisions are reached jointly. This review will focus on the perspectives of physicians and patients in relation to the diagnosis and management of systemic sclerosis-associated interstitial lung disease. Similarities and differences in these perspectives will be identified, and strategies for achieving optimal disease management will be proposed.

Derivation and Validation of a Diagnostic Prediction Tool for Interstitial Lung Disease

BACKGROUND

Interstitial lung disease (ILD) results in high morbidity and health-care utilization. Diagnostic delays remain common and often occur in nonpulmonology settings. Screening for ILD in these settings has the potential to reduce diagnostic delays and improve patient outcomes.

RESEARCH QUESTION

This study sought to determine whether a pulmonary function test (PFT)-derived diagnostic prediction tool (ILD-Screen) could accurately identify incident ILD cases in patients undergoing PFT in nonpulmonology settings.

STUDY DESIGN AND METHODS

Clinical and physiologic PFT variables predictive of ILD were identified by using iterative multivariable logistic regression models. ILD status was determined by using a multi-reader approach. An ILD-Screen score was generated by using final regression model coefficients, with a score ≥ 8 considered positive. ILD-Screen test performance was validated in an independent external cohort and applied prospectively to PFTs over 1 year to identify incident ILD cases at our institution.

RESULTS

Variables comprising the ILD-Screen were age, height, total lung capacity, FEV₁, diffusion capacity, and PFT indication. The ILD-Screen showed consistent test performance across cohorts, with a sensitivity of 0.79 and a specificity of 0.83 when applied prospectively. A positive ILD-Screen strongly predicted ILD (OR, 18.6; 95% CI, 9.4-36.9) and outperformed common ILD clinical features, including cough, dyspnea, lung crackles, and restrictive lung physiology. Prospective ILD-Screen application resulted in a higher proportion of patients undergoing chest CT imaging compared with a historical control cohort (74% vs 56%, respectively; P = .003), with a significantly shorter median time to chest CT imaging (5.6 vs 21.1 months; P < .001).

INTERPRETATION

The ILD-Screen showed good test performance in predicting ILD across diverse geographic settings and when applied prospectively. Systematic ILD-Screen application has the potential to reduce diagnostic delays and facilitate earlier intervention in patients with ILD.

Regional distribution of high-attenuation areas on chest computed tomography in the Multi-Ethnic Study of Atherosclerosis

High-attenuation areas (HAA) are a computed tomography-based quantitative measure of subclinical interstitial lung disease (ILD). We aimed to validate HAA in lung regions that are less subject to artefacts, such as extravascular lung water or dependent atelectasis. We examined the associations of HAA within six lung regions (basilar, non-basilar, peel, core, basilar peel, basilar core) with serum biomarkers of lung remodelling, forced vital capacity (FVC), visually-assessed interstitial lung abnormalities (ILA), and all-cause and ILD-specific mortality.

We performed cross-sectional and longitudinal analyses of participants in the Multi-Ethnic Study of Atherosclerosis, a prospective cohort of 6814 adults aged 45–84 years without known cardiovascular disease who underwent cardiac computed tomography.

Median regional HAA ranged from 3.8% in the peel to 4.8% in the basilar core. Doubling of regional HAA was associated with greater serum matrix metalloproteinase-7 (range 3.8% to 10.3%; p≤0.01), higher odds of ILA (OR 1.42 to 2.20; p≤0.03), and a higher risk of all-cause mortality (hazard ratio 1.20 to 1.47; p≤0.001). Doubling of regional HAA was associated with greater serum interleukin-6 (4.9% to 10.3%; p≤0.005) and higher risk of ILD-specific mortality (hazard ratio 3.30 to 3.98; p<0.001), except in the basilar core. Doubling of regional HAA was associated with lower FVC in the non-basilar, core and basilar core (113 mL to 186 mL; p<0.001).

Associations of HAA with lung remodelling biomarkers, ILA risk and all-cause mortality were consistent across all regions of the lung, including dependent areas where atelectasis may be present. These findings support the validity of HAA as a measure of pathologic subclinical ILD.

Evenwhen found in small regions of the lungs, high-attenuation areas, a CT-based quantitative measure of subclinical ILD, are associated with biomarkers of lung remodelling, risk of interstitial lung abnormalities and all-cause mortalityhttp://bit.ly/36psfin

Imaging research in fibrotic lung disease; applying deep learning to unsolved problems

Over the past decade, there has been a groundswell of research interest in computer-based methods for objectively quantifying fibrotic lung disease on high resolution CT of the chest. In the past 5 years, the arrival of deep learning-based image analysis has created exciting new opportunities for enhancing the understanding of, and the ability to interpret, fibrotic lung disease on CT. Specific unsolved problems for which computer-based imaging analysis might provide solutions include the development of reliable methods for assisting with diagnosis, detecting early disease, and predicting disease behaviour using baseline imaging data. However, to harness this technology, technical and societal challenges must be overcome. Large CT datasets will be needed to power the training of deep learning algorithms. Open science research and collaboration between academia and industry must be encouraged. Prospective clinical utility studies will be needed to test computer algorithm performance in real-world clinical settings and demonstrate patient benefit over current best practice. Finally, ethical standards, which ensure patient confidentiality and mitigate against biases in training datasets, that can be encoded in machine-learning systems will be needed as well as bespoke data governance and accountability frameworks to encourage buy-in from health-care professionals, patients, and the public.

Interstitial lung abnormalities in the Queensland Lung Cancer Screening Study: prevalence and progression over 2 years of surveillance

BACKGROUND

We report the prevalence and progression of incidentally detected interstitial lung abnormalities (ILA) in the Queensland Lung Cancer Screening Study cohort.

METHODS

About 256 volunteers aged 60-74, with ≥30 pack years smoking history and forced expiratory volume in 1 s (FEV1) ≥50% predicted underwent low-dose computed tomography (CT) chest screening. Electronic search of baseline (T0) and 2-year follow-up (T2) CT reports identified candidate cases using Fleischner Society interstitial terminology. Candidate CT were reviewed in a randomised order by two experienced radiologists and a senior respiratory medicine trainee blinded to the existing reports. Scans were evaluated for the presence and extent of ILA using an in-house score, and graded for progression.

RESULTS

ILA were detected in 20/256 baseline cases (7.8%) with no incident cases detected at T2 surveillance imaging. Of these 20 cases, 9 (45%) had reticulation, 18 (90%) had ground glass change, 1 had traction bronchiectasis and 1 had randomly distributed nodularity. Seven cases with ground glass changes also had areas of reticulation, and only two had reticulation alone. All ILA were graded as minor except for traction bronchiectasis, which was moderate. Only one case progressed on T2 imaging. ILA were associated with the presence of auscultatory crackles (50% vs 11.6%, P = 0.001) and a lesser degree of emphysema (mean % volumetric emphysema 6.7% vs 9.8%, P = 0.009). No relationship was observed between baseline and serial lung function parameters.

CONCLUSION

ILA are frequent incidental findings in lung cancer screening. In the majority of cases these abnormalities do not appear to change significantly over a 2-year period of surveillance.

Classification of Interstitial Lung Abnormality Patterns with an Ensemble of Deep Convolutional Neural Networks

Subtle interstitial changes in the lung parenchyma of smokers, known as Interstitial Lung Abnormalities (ILA), have been associated with clinical outcomes, including mortality, even in the absence of Interstitial Lung Disease (ILD). Although several methods have been proposed for the automatic identification of more advanced Interstitial Lung Disease (ILD) patterns, few have tackled ILA, which likely precedes the development ILD in some cases. In this context, we propose a novel methodology for automated identification and classification of ILA patterns in computed tomography (CT) images. The proposed method is an ensemble of deep convolutional neural networks (CNNs) that detect more discriminative features by incorporating two, two-and-a-half and three- dimensional architectures, thereby enabling more accurate classification. This technique is implemented by first training each individual CNN, and then combining its output responses to form the overall ensemble output. To train and test the system we used 37424 radiographic tissue samples corresponding to eight different parenchymal feature classes from 208 CT scans. The resulting ensemble performance including an average sensitivity of 91,41% and average specificity of 98,18% suggests it is potentially a viable method to identify radiographic patterns that precede the development of ILD.

Overlap of Genetic Risk between Interstitial Lung Abnormalities and Idiopathic Pulmonary Fibrosis

Rationale: Interstitial lung abnormalities (ILAs) are associated with the highest genetic risk locus for idiopathic pulmonary fibrosis (IPF); however, the extent to which there are unique associations among individuals with ILAs or additional overlap with IPF is not known.Objectives: To perform a genome-wide association study (GWAS) of ILAs.Methods: ILAs and a subpleural-predominant subtype were assessed on chest computed tomography (CT) scans in the AGES (Age Gene/Environment Susceptibility), COPDGene (Genetic Epidemiology of Chronic Obstructive Pulmonary Disease [COPD]), Framingham Heart, ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points), MESA (Multi-Ethnic Study of Atherosclerosis), and SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study) studies. We performed a GWAS of ILAs in each cohort and combined the results using a meta-analysis. We assessed for overlapping associations in independent GWASs of IPF.Measurements and Main Results: Genome-wide genotyping data were available for 1,699 individuals with ILAs and 10,274 control subjects. The MUC5B (mucin 5B) promoter variant rs35705950 was significantly associated with both ILAs (P = 2.6 × 10-27) and subpleural ILAs (P = 1.6 × 10-29). We discovered novel genome-wide associations near IPO11 (rs6886640, P = 3.8 × 10-8) and FCF1P3 (rs73199442, P = 4.8 × 10-8) with ILAs, and near HTRE1 (rs7744971, P = 4.2 × 10-8) with subpleural-predominant ILAs. These novel associations were not associated with IPF. Among 12 previously reported IPF GWAS loci, five (DPP9, DSP, FAM13A, IVD, and MUC5B) were significantly associated (P < 0.05/12) with ILAs.Conclusions: In a GWAS of ILAs in six studies, we confirmed the association with a MUC5B promoter variant and found strong evidence for an effect of previously described IPF loci; however, novel ILA associations were not associated with IPF. These findings highlight common genetically driven biologic pathways between ILAs and IPF, and also suggest distinct ones.

Questions and Answers on Smoking in Patients With Diffuse ILD. Use of PICO Methodology

INTRODUCTION

The Smoking and the Diffuse Interstitial Lung Diseases (ILD) groups of ALAT and SEPAR collaborated in the preparation of this document.

MATERIALS AND METHODS

This document uses PICO methodology to answer various questions on the relationship between tobacco use and diffuse ILD.

RESULTS AND CONCLUSIONS

The main recommendations are: a) moderate level of evidence and strong recommendation to consider smoking as a risk factor for the development and/or modification of the progression of diffuse ILD; b) moderate level of evidence to identify an increase in mortality in diffuse ILD, irrespective of histologic pattern. Low evidence for ascribing it to smoking and strong recommendation for the early identification of patients with diffuse ILD. Further studies are needed to evaluate the effect of smoking cessation in patients with diffuse ILD; c) low level of evidence and weak recommendation for defining the impact of passive smoking in diffuse ILD; d) low level of evidence to demonstrate that smoking cessation improves the outcomes of patients diagnosed with diffuse ILD and strong recommendation to advise smoking cessation in smokers with diffuse ILD, and e) low level of evidence to support the clinical or epidemiological usefulness of active case finding for diffuse ILD in smoking cessation programs, and strong recommendation justifying the performance of spirometry in active case finding, based not on current smoking status, but on previous accumulated consumption, even in asymptomatic cases.

Idiopathic Pulmonary Fibrosis Is a Genetic Disease Involving Mucus and the Peripheral Airways

Idiopathic pulmonary fibrosis (IPF) is localized to the lung, is characterized by a pattern of heterogeneous, subpleural patches of fibrotic, remodeled lung, and is associated with a median survival of 3-5 years after diagnosis. A common gain-of-function MUC5B promoter variant, rs35705950, is the strongest risk factor (genetic and otherwise), accounting for at least 30% of the total risk of developing IPF. The MUC5B promoter variant can be used to identify individuals in the preclinical phase of this progressive disease, and, in the IPF lung, we have found that MUC5B is specifically overexpressed in bronchoalveolar epithelium. Thus, MUC5B represents a key molecule to understand the mechanisms that appear to initiate the fibroproliferative process in the bronchoalveolar epithelium. Moreover, focusing on MUC5B may provide a unique opportunity to define the early molecular events that lead to, and potentially prevent, the development of IPF.

Integrated evaluation of clinical, pathological and radiological prognostic factors in squamous cell carcinoma of the lung

Objective

Little is known about prognostic factors for lung squamous cell carcinoma (SCC). We aimed to explore radiologic and clinical factors affecting prognosis and to compare the prognosis of both central and peripheral lung SCCs.

Materials and methods

Radiologic, clinical, and pathologic profiles of surgically confirmed SCCs from 382 patients were retrospectively reviewed. Tumor location, enhancement, necrosis, the presence of obstructive pneumonitis/atelectasis and underlying lung disease were evaluated on chest CT examination. Age, pulmonary function, tumor marker, and cancer stage were also assessed. Univariate and multivariate Cox regression analyses were performed to identify any correlation to overall survival (OS) and disease-free survival (DFS). Hazard rate estimation and competing risk analysis were done to evaluate recurrence pattern.

Results

The median follow-up period was 56.2 months. Tumors were located centrally in 230 patients (60.2%) and peripherally in 152 patients (39.8%). Age (p = 0.002, hazard ratio [HR] 1.03, 95% confidence interval [CI] = [1.01, 1.06]) and interstitial lung abnormalities (ILAs) (p<0.001, HR 5.41, 95% CI = [3.08, 9.52]) were associated with poor OS on multivariate analysis. ILAs also had a strong association to DFS (p<0.001, HR 4.25, 95% CI = [3.08, 9.52]). Central cancers had two peaks of local recurrence development at 15 and 60 months after surgery, and peripheral tumors showed rising curves for metastasis development at 60 months.

Conclusions

CT-determined ILAs are a strong biomarker predicting poor outcome. Prognosis may not vary according to tumor location, but the two groups exhibited different recurrence patterns.

Circulating adhesion molecules and subclinical interstitial lung disease: the Multi-Ethnic Study of Atherosclerosis

Adhesion molecules may contribute to the development of interstitial lung disease (ILD) and have been proposed as prognostic biomarkers in idiopathic pulmonary fibrosis. Our objective was to determine whether the circulating adhesion molecules soluble intracellular adhesion molecule (sICAM)-1, soluble vascular cell adhesion molecule (sVCAM)-1 and P-selectin are associated with subclinical ILD in community-dwelling adults.The Multi-Ethnic Study of Atherosclerosis enrolled males and females aged 45-84 years from six communities in the United States in 2000-2002. High attenuation areas were defined as the percentage of imaged lung volume with attenuation -600--250 HU on cardiac computed tomography (CT). Interstitial lung abnormalities were visually assessed on full-lung CT. Spirometry was performed on a subset of individuals. ILD hospitalisations and deaths were adjudicated.In fully adjusted analyses, higher levels of sICAM-1, sVCAM-1 and P-selectin were associated with greater high attenuation areas (2.94%, 95% CI 1.80-4.07%; 1.24%, 95% CI 0.14-2.35%; and 1.58%, 95% CI 0.92-2.23%, respectively), and greater rate of ILD hospitalisations (HR 1.36, 95% CI 1.03-1.80; 1.40, 95% CI 1.07-1.85; and 2.03, 95% CI 1.16-3.5, respectively). sICAM-1 was associated with greater prevalence of interstitial lung abnormalities (OR 1.39, 95% CI 1.13-1.71). sICAM-1 and P-selectin were associated with lower forced vital capacity (44 mL, 95% CI 12-76 mL and 29 mL, 95% CI 8-49 mL, respectively). sVCAM-1 and P-selectin were associated with increased risk of ILD death (HR 2.15, 95% CI 1.26-3.64 and 3.61, 95% CI 1.54-8.46, respectively).Higher levels of circulating sICAM-1, sVCAM-1 and P-selectin are independently associated with CT and spirometric measures of subclinical ILD, and increased rate of adjudicated ILD events among community-dwelling adults.

MUC5B variant is associated with visually and quantitatively detected preclinical pulmonary fibrosis

BACKGROUND

Relatives of patients with familial interstitial pneumonia (FIP) are at increased risk for pulmonary fibrosis. We assessed the prevalence and risk factors for preclinical pulmonary fibrosis (PrePF) in first-degree relatives of patients with FIP and determined the utility of deep learning in detecting PrePF on CT.

METHODS

First-degree relatives of patients with FIP over 40 years of age who believed themselves to be unaffected by pulmonary fibrosis underwent CT scans of the chest. Images were visually reviewed, and a deep learning algorithm was used to quantify lung fibrosis. Genotyping for common idiopathic pulmonary fibrosis risk variants in MUC5B and TERT was performed.

FINDINGS

In 494 relatives of patients with FIP from 263 families of patients with FIP, the prevalence of PrePF on visual CT evaluation was 15.6% (95% CI 12.6 to 19.0). Compared with visual CT evaluation, deep learning quantitative CT analysis had 84% sensitivity (95% CI 0.72 to 0.89) and 86% sensitivity (95% CI 0.83 to 0.89) for discriminating subjects with visual PrePF diagnosis. Subjects with PrePF were older (65.9, SD 10.1 years) than subjects without fibrosis (55.8 SD 8.7 years), more likely to be male (49% vs 37%), more likely to have smoked (44% vs 27%) and more likely to have the MUC5B promoter variant rs35705950 (minor allele frequency 0.29 vs 0.21). MUC5B variant carriers had higher quantitative CT fibrosis scores (mean difference of 0.36%), a difference that remains significant when controlling for age and sex.

INTERPRETATION

PrePF is common in relatives of patients with FIP. Its prevalence increases with age and the presence of a common MUC5B promoter variant. Quantitative CT analysis can detect these imaging abnormalities.