Search

Background and Objective Pulmonary hypertension is a life-limiting complication of interstitial lung disease (ILD-PH). We investigated whether treatment with phosphodiesterase 5 inhibitors (PDE5i) in patients with ILD-PH was associated with improved survival. Methods Consecutive incident patients with ILD-PH and right heart catheterisation, echocardiography and spirometry data were followed from diagnosis to death, transplantation or censoring with all follow-up and survival data modelled by Bayesian methods. Results The diagnoses in 128 patients were idiopathic pulmonary fibrosis (n = 74, 58%), hypersensitivity pneumonitis (n = 17, 13%), non-specific interstitial pneumonia (n = 12, 9%), undifferentiated ILD (n = 8, 6%) and other lung diseases (n = 17, 13%). Final outcomes were death (n = 106, 83%), transplantation (n = 9, 7%) and censoring (n = 13, 10%). Patients treated with PDE5i (n = 50, 39%) had higher mean pulmonary artery pressure (median 38 mm Hg [interquartile range, IQR: 34, 43] vs. 35 mm Hg [IQR: 31, 38], p = 0.07) and percentage predicted forced vital capacity (FVC; median 57% [IQR: 51, 73] vs. 52% [IQR: 45, 66], p=0.08) though differences did not reach significance. Patients treated with PDE5i survived longer than untreated patients (median 2.18 years [95% CI: 1.43, 3.04] vs. 0.94 years [0.69, 1.51], p = 0.003) independent of all other prognostic markers by Bayesian joint-modelling (HR 0.39, 95% CI: 0.23, 0.59, p

This report presents the proceedings from a workshop titled "Microbiome, Metabolism and Immunoregulation of Asthma" that was held virtually May 13 and 14, 2021. The workshop was jointly sponsored by the American Thoracic Society (Assembly on Allergy, Immunology, and Inflammation) and the National Institute of Allergy and Infectious Diseases. It convened an interdisciplinary group of experts with backgrounds in asthma immunology, microbiome science, metabolomics, computational biology, and translational pulmonary research. The main purpose was to identify key scientific gaps and needs to further advance research on microbial and metabolic mechanisms that may contribute to variable immune responses and disease heterogeneity in asthma. Discussions were structured around several topics, including 1) immune and microbial mechanisms of asthma pathogenesis in murine models, 2) the role of microbes in pediatric asthma exacerbations, 3) dysregulated metabolic pathways in asthma associated with obesity, 4) metabolism effects on macrophage function in adipose tissue and the lungs, 5) computational approaches to dissect microbiome-metabolite links, and 6) potential confounders of microbiome-disease associations in human studies. This report summarizes the major points of discussion, which included identification of specific knowledge gaps, challenges, and suggested directions for future research. These include questions surrounding mechanisms by which microbiota and metabolites shape host health versus an allergic or asthmatic state; direct and indirect influences of other biological factors, exposures, and comorbidities on these interactions; and ongoing technical and analytical gaps for clinical translation.

RATIONALE: Genetic studies of Idiopathic Pulmonary Fibrosis (IPF) have improved our understanding of this disease, but not all causal loci have been identified. OBJECTIVE: To identify genes enriched with rare deleterious variants in IPF and familial pulmonary fibrosis. METHODS: We performed gene burden analysis of whole exome data, tested single variants for disease association, conducted KIF15 functional studies, and examined human lung single cell RNA sequencing data. MEASUREMENT AND MAIN RESULTS: Gene burden analysis of 1,725 cases and 23,509 controls identified heterozygous rare deleterious variants in KIF15, a kinesin involved in spindle separation during mitosis, and three telomere-related genes (TERT, RTEL1, PARN). KIF15 was implicated in autosomal dominant models of rare deleterious variants (OR 4.9 [95%CI 2.7, 8.8] P=2.55x10-7) and rare protein-truncating variants (OR 7.6 [3.3, 17.1], P=8.12x10-7). Meta-analysis of the discovery and replication cohorts, including 2,966 cases and 29,817 controls, confirm the involvement of KIF15, plus the three telomere-related genes. A common variant within a KIF15 intron (rs74341405, OR 1.6 [1.4, 1.9], P=5.63x10-10) is associated with IPF risk, confirming a prior report. Lymphoblastoid cells from individuals heterozygous for the common variant have decreased KIF15 and reduced rates of cell growth. Cell proliferation is dependent on KIF15 in the presence of an inhibitor of Eg5/KIF11, which has partially redundant function. KIF15 is expressed specifically in replicating human lung cells, and shows diminished expression in replicating epithelial cells of IPF patients. CONCLUSIONS: Both rare deleterious variants and common variants in KIF15 link a non-telomerase pathway of cell proliferation with IPF susceptibility.

Genome-wide rare variant studies of IPF patients of non-European ancestry have been understudied. Here, we evaluate the enrichment of rare genetic variants of 241 unrelated non-European cases, representing individuals of Latino, African, South Asian, East Asian, and Other Admixed ancestry. Gene burden analysis of deleterious rare (protein-truncating and missense) variants demonstrate an excess of TERT rare damaging variants (OR 67.1, 95% CI [23.1, 195.0], P = 9.4 x 10-14) in non-European subjects. Analysis by ancestry demonstrated an excess of rare, damaging TERT variants in the Latino subgroup (OR 80.9, 95% CI [17.3, 383.8], P = 2.6 x 10-8). Although the non-European group did not show enrichment of PARN, RTEL1, and KIF15 rare deleterious variants, these groups all showed a trend in the same direction as the European ancestry group. For TERT and KIF15, the inclusion of IPF patients of non-European ancestry led to a higher odds ratios and increased evidence in favor of rare deleterious variant contributions, thus demonstrating the increased power of multi-ethnic studies over single-ethnicity studies. To our knowledge, this is the first study that confirms the involvement of rare deleterious TERT variants for IPF patients of Latino and non-European ancestry. To better understand the genetic underpinnings of IPF patients of all ancestries, additional work will be needed to broaden patient recruitment to normalize imbalances.

BackgroundConsiderable clinical heterogeneity in idiopathic pulmonary fibrosis (IPF) suggests the existence of multiple disease endotypes. Identifying these endotypes would improve our understanding of the pathogenesis of IPF and could allow for a biomarker-driven personalised medicine approach. We aimed to identify clinically distinct groups of patients with IPF that could represent distinct disease endotypes.MethodsWe co-normalised, pooled and clustered three publicly available blood transcriptomic datasets (total 220 IPF cases). We compared clinical traits across clusters and used gene enrichment analysis to identify biological pathways and processes that were over-represented among the genes that were differentially expressed across clusters. A gene-based classifier was developed and validated using three additional independent datasets (total 194 IPF cases).FindingsWe identified three clusters of patients with IPF with statistically significant differences in lung function (p=0.009) and mortality (p=0.009) between groups. Gene enrichment analysis implicated mitochondrial homeostasis, apoptosis, cell cycle and innate and adaptive immunity in the pathogenesis underlying these groups. We developed and validated a 13-gene cluster classifier that predicted mortality in IPF (high-risk clusters vs low-risk cluster: HR 4.25, 95% CI 2.14 to 8.46, p=3.7×10−5).InterpretationWe have identified blood gene expression signatures capable of discerning groups of patients with IPF with significant differences in survival. These clusters could be representative of distinct pathophysiological states, which would support the theory of multiple endotypes of IPF. Although more work must be done to confirm the existence of these endotypes, our classifier could be a useful tool in patient stratification and outcome prediction in IPF.

Background The adherence to and clinical efficacy of pulmonary rehabilitation in idiopathic pulmonary fibrosis (IPF), particularly in comparison to people with chronic obstructive pulmonary disease (COPD), remains uncertain. The objectives of this real-world study were to compare the responses of patients with IPF with a matched group of patients with COPD undergoing the same supervised, outpatient pulmonary rehabilitation program, and to determine whether pulmonary rehabilitation is associated with survival in IPF. Research question Do people with IPF improve to the same extent with pulmonary rehabilitation as a matched group of individuals with COPD, and are non-completion of and/or non-response to pulmonary rehabilitation associated with one-year all-cause mortality in IPF? Study design and methods Using propensity score matching, 163 patients with IPF were matched 1:1 with a control group of 163 patients with COPD referred to pulmonary rehabilitation. We compared between-group pulmonary rehabilitation completion rates and response. Survival status in the IPF cohort was recorded over one-year following pulmonary rehabilitation discharge. Cox proportional-hazards regression explored the association between pulmonary rehabilitation status and all-cause mortality. Results Similar pulmonary rehabilitation completion rates (IPF: 69%; COPD: 63%; p=0.24) and improvements in exercise response were observed in both groups with no significant mean (95% confidence interval (CI)) between-group differences in incremental shuttle walk (ISW) change (2 (-18 to 22) meters). Pulmonary rehabilitation non-completion (hazard ratio (HR) (95%CI) 5.62 (2.24 to 14.08)) and non-response (HR (95%CI) 3.91 (1.54 to 9.93)) were independently associated with increased one-year all-cause mortality in IPF. Interpretation Compared with a matched group of patients with COPD, this real-word study demonstrates that patients with IPF have similar completion rates and magnitude of response to pulmonary rehabilitation. In IPF, non-completion of and non-response to pulmonary rehabilitation were associated with increased all-cause mortality. These data reinforce the benefits of pulmonary rehabilitation in patients with IPF.

Background and objective A proportion of patients with fibrotic hypersensitivity pneumonitis (fHP) follow a progressive disease course despite immunosuppressive treatment. Little is known about predictors of mortality in fHP. We aimed to investigate the impact of short-term lung function changes in fHP on mortality. Methods Baseline demographics for 145 consecutive patients with a multi-disciplinary team diagnosis of fHP, as well as baseline and 1-year follow-up of lung function, baseline echocardiographic findings, bronchoalveolar lavage (BAL) cellularity and all-cause mortality were recorded. Changes in forced vital capacity (FVC) ≥ 5% and ≥10%, and diffusion capacity of the lung for carbon monoxide (DLCO) ≥ 10% and ≥15% at 1 year were calculated. Cox proportional hazards analysis was performed to test for associations with mortality. Results Baseline lung function severity, age, presence of honeycombing on computed tomography (CT) and echocardiographic pulmonary arterial systolic pressure (PASP) ≥ 40 mm Hg were associated with early mortality, while BAL lymphocytosis was associated with improved survival. A decline in FVC ≥ 5% (hazard ratio [HR]: 3.10, 95% CI: 2.00–4.81, p

Data Availability Statement: We did not obtain consent from participants to share their data outside of this study. Supporting information is available online at: https://onlinelibrary.wiley.com/doi/10.1111/resp.14494#support-information-section . Copyright © 2023 The Authors. Background and Objective: Gait speed is associated with survival in individuals with idiopathic pulmonary fibrosis (IPF). The extent to which four-metre gait speed (4MGS) decline predicts adverse outcome in IPF remains unclear. We aimed to examine longitudinal 4MGS change and identify a cut-point associated with adverse outcome. Methods: In a prospective cohort study, we recruited 132 individuals newly diagnosed with IPF and measured 4MGS change over 6 months. Death/first hospitalization at 6 months were composite outcome events. Complete data (paired 4MGS plus index event) were available in 85 participants; missing 4MGS data were addressed using multiple imputation. Receiver-Operating Curve plots identified a 4MGS change cut-point. Cox proportional-hazard regression assessed the relationship between 4MGS change and time to event. Results: 4MGS declined over 6 months (mean [95% CI] change: −0.05 [−0.09 to −0.01] m/s; p = 0.02). A decline of 0.07 m/s or more in 4MGS over 6 months had better discrimination for the index event than change in 6-minute walk distance, forced vital capacity, Composite Physiologic Index or Gender Age Physiology index. Kaplan–Meier curves demonstrated a significant difference in time to event between 4MGS groups (substantial decline: >−0.07 m/s versus minor decline/improvers: ≤−0.07 m/s; p = 0.007). Those with substantial decline had an increased risk of hospitalization/death (adjusted hazard ratio [95% CI] 4.61 [1.23–15.83]). Similar results were observed in multiple imputation analysis. Conclusion: In newly diagnosed IPF, a substantial 4MGS decline over 6 months is associated with shorter time to hospitalization/death at 6 months. 4MGS change has potential as a surrogate endpoint for interventions aimed at modifying hospitalization/death. Research Trainees Coordinating Centre. Grant Number: 2014-07-089.

Data sharing: The PHOSP-COVID study protocol, consent form, definition, and derivation of clinical characteristics and outcomes, training materials, regulatory documents, information about requests for data access, and other relevant study materials are available online. UK Biobank information can be released once necessary approvals have been obtained. Other data (eg, the R code and protocol) will be made available on reasonable request to the corresponding author. Copyright © 2023 The Author(s). Background: Sleep disturbance is common following hospital admission both for COVID-19 and other causes. The clinical associations of this for recovery after hospital admission are poorly understood despite sleep disturbance contributing to morbidity in other scenarios. We aimed to investigate the prevalence and nature of sleep disturbance after discharge following hospital admission for COVID-19 and to assess whether this was associated with dyspnoea. Methods: CircCOVID was a prospective multicentre cohort substudy designed to investigate the effects of circadian disruption and sleep disturbance on recovery after COVID-19 in a cohort of participants aged 18 years or older, admitted to hospital for COVID-19 in the UK, and discharged between March, 2020, and October, 2021. Participants were recruited from the Post-hospitalisation COVID-19 study (PHOSP-COVID). Follow-up data were collected at two timepoints: an early time point 2–7 months after hospital discharge and a later time point 10–14 months after hospital discharge. Sleep quality was assessed subjectively using the Pittsburgh Sleep Quality Index questionnaire and a numerical rating scale. Sleep quality was also assessed with an accelerometer worn on the wrist (actigraphy) for 14 days. Participants were also clinically phenotyped, including assessment of symptoms (ie, anxiety [Generalised Anxiety Disorder 7-item scale questionnaire], muscle function [SARC-F questionnaire], dyspnoea [Dyspnoea-12 questionnaire] and measurement of lung function), at the early timepoint after discharge. Actigraphy results were also compared to a matched UK Biobank cohort (non-hospitalised individuals and recently hospitalised individuals). Multivariable linear regression was used to define associations of sleep disturbance with the primary outcome of breathlessness and the other clinical symptoms. PHOSP-COVID is registered on the ISRCTN Registry (ISRCTN10980107). Findings: 2320 of 2468 participants in the PHOSP-COVID study attended an early timepoint research visit a median of 5 months (IQR 4–6) following discharge from 83 hospitals in the UK. Data for sleep quality were assessed by subjective measures (the Pittsburgh Sleep Quality Index questionnaire and the numerical rating scale) for 638 participants at the early time point. Sleep quality was also assessed using device-based measures (actigraphy) a median of 7 months (IQR 5–8 months) after discharge from hospital for 729 participants. After discharge from hospital, the majority (396 [62%] of 638) of participants who had been admitted to hospital for COVID-19 reported poor sleep quality in response to the Pittsburgh Sleep Quality Index questionnaire. A comparable proportion (338 [53%] of 638) of participants felt their sleep quality had deteriorated following discharge after COVID-19 admission, as assessed by the numerical rating scale. Device-based measurements were compared to an age-matched, sex-matched, BMI-matched, and time from discharge-matched UK Biobank cohort who had recently been admitted to hospital. Compared to the recently hospitalised matched UK Biobank cohort, participants in our study slept on average 65 min (95% CI 59 to 71) longer, had a lower sleep regularity index (–19%; 95% CI –20 to –16), and a lower sleep efficiency (3·83 percentage points; 95% CI 3·40 to 4·26). Similar results were obtained when comparisons were made with the non-hospitalised UK Biobank cohort. Overall sleep quality (unadjusted effect estimate 3·94; 95% CI 2·78 to 5·10), deterioration in sleep quality following hospital admission (3·00; 1·82 to 4·28), and sleep regularity (4·38; 2·10 to 6·65) were associated with higher dyspnoea scores. Poor sleep quality, deterioration in sleep quality, and sleep regularity were also associated with impaired lung function, as assessed by forced vital capacity. Depending on the sleep metric, anxiety mediated 18–39% of the effect of sleep disturbance on dyspnoea, while muscle weakness mediated 27–41% of this effect. Interpretation: Sleep disturbance following hospital admission for COVID-19 is associated with dyspnoea, anxiety, and muscle weakness. Due to the association with multiple symptoms, targeting sleep disturbance might be beneficial in treating the post-COVID-19 condition. Funding: UK Research and Innovation, National Institute for Health Research, and Engineering and Physical Sciences Research Council. UK Research and Innovation, National Institute for Health Research, and Engineering and Physical Sciences Research Council.

SummaryAllergic asthma generally starts during early life and is linked to significant tissue remodelling and lung dysfunction. Although angiogenesis is a feature of the disrupted airway, the impact of allergic asthma on the pulmonary microcirculation during early life is unknown. Here, using quantitative imaging in precision-cut lung slices (PCLS), we report that exposure of neonatal mice to house dust mite (HDM) extract disrupts endothelial cell/pericyte interactions in adventitial areas. Central to the blood vessel structure, the loss of pericyte coverage was driven by mast cell (MCs) proteases, such as tryptase, that can induce pericyte retraction and loss of the critical adhesion molecule N-Cadherin. Furthermore, spatial transcriptomics of paediatric asthmatic endobronchial biopsies revealed intense remodelling associated with increased expression of MC proteases in regions enriched in blood vessels. These data provide previously unappreciated insights into the pathophysiology of allergic asthma with potential long-term vascular defects.

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by limited treatment options and high mortality. A better understanding of the molecular drivers of IPF progression is needed. OBJECTIVE: To identify and validate molecular determinants of IPF survival. METHODS: A staged genome-wide association study (GWAS) was performed using paired genomic and survival data. Stage I cases were drawn from centers across the US and Europe and stage II cases from Vanderbilt University. Cox proportional hazards regression was used to identify gene variants associated with differential transplant-free survival (TFS). Stage I variants with nominal significance (p

Background Pulmonary fibrosis (PF) is caused by a heterogeneous group of diseases, with a high inter-individual variability in disease trajectory. Identifying disease progression in patients with PF has impact on clinical management decisions. However, strategies to early identify and predict disease progression for these patients are currently lacking. In this study, we aim to assess long-term FVC change in patients with PF measured with home spirometry, and evaluate the feasibility of a multinational patient-led registry in PF. In addition, we will assess validity of patient-reported outcomes (PROMs) for the different subgroups of patients with PF. Methods In this international, prospective, multicenter, observational study, we aim to include 700 patients across seven European countries. Patients will monitor their disease course for a period of two years using an online home monitoring program (I-FILE), which includes home spirometry, pulse oximetry, and PROMs. Results will be directly sent to the hospital via the online application. Patients will be asked to perform daily home spirometry and pulse oximetry in the first three months, followed by once weekly measurements for a period of two years. PROMs will be completed in the online I-FILE application every six months, including the King’s brief Interstitial Lung Disease Health Status, The EuroQol five dimensions five-level, Visual Analogue Scales on cough, dyspnea, fatigue and general complaints, Leicester Cough Questionnaire, Fatigue Assessment Scale, Work Productivity and Activity Impairment Questionnaire, Global Rating of Change Scale, and Living with Pulmonary Fibrosis questionnaire. Discussion This study will provide much needed insights in disease trajectories of the different subgroups of patients with PF. Simultaneously, the I-FILE study will yield valuable information on the use and feasibility of home-based data collection. This international patient-led registry will facilitate trans-border collaboration to further optimize care and research for patients with PF. Trial registration: The study was registered on the 12th of March 2020 in the International Clinical Trial Registry, www.clinicaltrials.gov; Identifier: NCT04304898.

Rationale: Idiopathic pulmonary fibrosis is a rare, irreversible, and progressive disease of the lungs. Common genetic variants, in addition to non-genetic factors, have been consistently associated with IPF. Rare variants identified by candidate gene, family-based, and exome studies have also been reported to associate with IPF. However, the extent to which rare variants genome-wide may contribute to the risk of IPF remains unknown. Objectives: We used whole-genome sequencing to investigate the role of rare variants, genome-wide, on IPF risk. Methods: As part of the Trans-Omics for Precision Medicine Program, we sequenced 2,180 cases of IPF. Association testing focused on the aggregated effect of rare variants (minor allele frequency ≤0.01) within genes or regions. We also identified individual variants that are influential within genes and estimated the heritability of IPF based on rare and common variants. Measurements and Main Results: Rare variants in both TERT and RTEL1 were significantly associated with IPF. A single rare variant in each of the TERT and RTEL1 genes was found to consistently influence the aggregated test statistics. There was no significant evidence of association with other previously reported rare variants. The SNP-heritability of IPF was estimated to be 32% (s.e. 3%). Conclusions: Rare variants within the TERT and RTEL1 genes and well-established common variants have the largest contribution to IPF risk overall. Efforts in risk profiling or development of therapies for IPF that focus on TERT, RTEL1, common variants, and environmental risk factors are likely to have the largest impact on this complex disease.

Interstitial lung abnormalities (ILA) can be incidentally detected in patients undergoing low-dose CT screening for lung cancer. In this retrospective study, we explore the downstream impact of ILA detection on interstitial lung disease (ILD) diagnosis and treatment. Using a targeted approach in a lung cancer screening programme, the rate of de novo ILD diagnosis was 1.5%. The extent of abnormality on CT and severity of lung function impairment, but not symptoms were the most important factors in differentiating ILA from ILD. Disease modifying therapies were commenced in 39% of ILD cases, the majority being antifibrotic therapy for idiopathic pulmonary fibrosis.

Aberrant expansion of KRT5+basal cells in the distal lung accompanies progressive alveolar epithelial cell loss and tissue remodelling during fibrogenesis in idiopathic pulmonary fibrosis (IPF). The mechanisms determining activity of KRT5+cells in IPF have not been delineated. Here, we reveal a potential mechanism by which KRT5+cells migrate within the fibrotic lung, navigating regional differences in collagen topography.In vitro, KRT5+cell migratory characteristics and expression of remodelling genes are modulated by extracellular matrix (ECM) composition and organisation. Mass spectrometry-based proteomics revealed compositional differences in ECM components secreted by primary human lung fibroblasts (HLF) from IPF patients compared to controls. Over-expression of ECM glycoprotein, Secreted Protein Acidic and Cysteine Rich (SPARC) in the IPF HLF matrix restricts KRT5+cell migrationin vitro. Together, our findings demonstrate how changes to the ECM in IPF directly influence KRT5+cell behaviour and function contributing to remodelling events in the fibrotic niche.

Background and objective: The minor T-allele of the MUC5B promoter polymorphism rs35705950 is strongly associated with idiopathic pulmonary fibrosis (IPF). However, conflicting results have been reported on the relationship between the MUC5B minor allele and survival and it is unknown whether a specific subgroup of IPF patients might benefit from MUC5B minor allele carriage. We investigated the association between MUC5B rs35705950, survival and patient characteristics in a real-world population of European IPF patients. Methods: In this retrospective study, 1751 patients with IPF from 8 European centres were included. MUC5B rs35705950 genotype, demographics, clinical characteristics at diagnosis and survival data were analysed. Results: In a multi-variate Cox proportional hazard model the MUC5B minor allele was a significant independent predictor of survival when adjusted for age, sex, high resolution computed tomography pattern, smoking behaviour and pulmonary function tests in IPF. MUC5B minor allele carriers were significantly older at diagnosis (p = 0.001). The percentage of MUC5B minor allele carriers increased significantly with age from 44% in patients aged 75. In IPF patients aged

Suppose a scholar seeks to understand the American Revolutionary War: its causes, consequences, and what lessons we may learn from it. They begin by reading biographies of key participants, but soon realize the scope of these books is too narrow. Broadening the scope to study demography (e.g., census reports, immigration records) helps them understand not merely the leaders of the revolution but also the people they led. Yet even this isn’t enough to understand the colonists’ activities, so the scope is broadened further to interactions: in governance (political science), in the marketplace (economics), and in culture (sociology). Finally, our historian realizes they cannot understand the events of Boston, Philadelphia, and Yorktown without also studying England: the leaders, people, and interactions that influenced a revolution from across an ocean.

RATIONALE: Shared symptoms and genetic architecture between COVID-19 and lung fibrosis suggests SARS-CoV-2 infection may lead to progressive lung damage.OBJECTIVES: The UKILD Post-COVID study interim analysis was planned to estimate the prevalence of residual lung abnormalities in people hospitalized with COVID-19 based on risk strata.METHODS: The Post-HOSPitalisation COVID Study (PHOSP-COVID) was used for capture of routine and research follow-up within 240 days from discharge. Thoracic CTs linked by PHOSP-COVID identifiers were scored for percentage of residual lung abnormalities (ground glass opacities and reticulations). Risk factors in linked CT were estimated with Bayesian binomial regression and risk strata were generated. Numbers within strata were used to estimate post-hospitalization prevalence using Bayesian binomial distributions. Sensitivity analysis was restricted to participants with protocol driven research follow-up.MEASUREMENTS AND MAIN RESULTS: The interim cohort comprised 3700 people. Of 209 subjects with linked CTs (median 119 days, interquartile range 83-155), 166 people (79.4%) had >10% involvement of residual lung abnormalities. Risk factors included abnormal chest X-ray (RR 1·21 95%CrI 1·05; 1·40), percent predicted DLcoCONCLUSIONS: Residual lung abnormalities were estimated in up to 11% of people discharged following COVID-19 related hospitalization. Health services should monitor at-risk individuals to elucidate long-term functional implications. This article is open access and distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).

Rationale: There is an urgent need for simple, cost-effective prognostic biomarkers for idiopathic pulmonary fibrosis (IPF); biomarkers that show potential include monocyte count. Objectives: We used pooled data from pirfenidone and interferon gamma-1b trials to explore the association between monocyte count and prognosis in patients with IPF. Methods: This retrospective pooled analysis included patients (active and placebo arms) from four Phase III, randomized, placebo-controlled trials: ASCEND (NCT01366209), CAPACITY (NCT00287729 and NCT00287716), and INSPIRE (NCT00075998). Outcomes included IPF progression (≥10% absolute decline in percent predicted forced vital capacity, ≥50 m decline in 6-minute walk distance, or death), all-cause hospitalization, and all-cause mortality over 1 year. The relationship between monocyte count (defined as time-dependent) and outcomes was assessed using bivariate and multivariable models. Measurements and Main Results: This analysis included 2067 patients stratified by monocyte count (at baseline

BackgroundGastro-esophageal reflux disease (GERD) is associated with idiopathic pulmonary fibrosis (IPF) in observational studies. It is not known if this association arises because GERD causes IPF, or IPF causes GERD, or because of confounding by factors, such as smoking, associated with both GERD and IPF. We used bidirectional Mendelian randomisation (MR), where genetic variants are used as instrumental variables to address issues of confounding and reverse causation, to examine how, if at all, GERD and IPF are causally related.Methods and resultsA bidirectional two-sample MR was performed to estimate the causal effect of GERD on IPF risk, and of IPF on GERD risk, using genetic data from the largest GERD (78,707 cases and 288,734 controls) and IPF (4,125 cases and 20,464 controls) genome-wide association meta-analyses currently available. GERD increased the risk of IPF, with an odds ratio (OR) of 1.6 (95% Confidence Interval, CI: 1.04-2.49; p=0.032). There was no evidence of a causal effect of IPF on the risk of GERD, with an OR of 0.99 (95%CI: 0.97-1.02; p=0.615).ConclusionWe found that GERD increases the risk of IPF, but found no evidence that IPF increases the risk of GERD. GERD should be considered in future studies of IPF risk, and interest in it as a potential therapeutic target should be renewed. The mechanisms underlying the effect of GERD on IPF should also be investigated.

RATIONALE: Criteria for progressive pulmonary fibrosis (PPF) have been proposed, but their prognostic value beyond categorical decline in forced vital capacity (FVC) remains unclear. OBJECTIVE: To determine whether proposed PPF criteria predict transplant-free survival (TFS) in patients with non-idiopathic pulmonary fibrosis (IPF) forms of interstitial lung disease (ILD). METHODS: A retrospective, multi-center cohort analysis was performed. Patients diagnosed with fibrotic connective tissue disease associated ILD, fibrotic hypersensitivity pneumonitis and non-IPF idiopathic interstitial pneumonia from three US centers and one UK center comprised test and validation cohorts, respectively. Cox proportional hazards regression was used to test the association between five-year TFS and 10% FVC decline, followed by thirteen additional PPF criteria satisfied in the absence of >=10% FVC decline. MAIN RESULTS: One thousand three hundred forty-one patients met inclusion criteria. A >=10% relative FVC decline was the strongest predictor of reduced TFS and showed consistent TFS association across cohorts, ILD subtypes and treatment groups, resulting in a phenotype that closely resembled IPF. Ten additional PPF criteria satisfied in the absence of >=10% relative FVC decline were also associated with reduced TFS in the US test cohort, with six maintaining TFS association in the UK validation cohort. Validated PPF criteria requiring a combination of physiologic, radiologic, and symptomatic worsening performed similarly to their stand-alone components but captured a smaller number of patients. CONCLUSIONS: An FVC decline of >=10% and six additional PPF criteria satisfied in the absence of such decline identify non-IPF ILD patients at increased risk of death or lung transplant.

BackgroundGastro-oesophageal reflux disease (GORD) is associated with idiopathic pulmonary fibrosis (IPF) in observational studies. It is not known if this association arises because GORD causes IPF or because IPF causes GORD, or because of confounding by factors, such as smoking, associated with both GORD and IPF. We used bidirectional Mendelian randomisation (MR), where genetic variants are used as instrumental variables to address issues of confounding and reverse causation, to examine how, if at all, GORD and IPF are causally related.MethodsA bidirectional two-sample MR was performed to estimate the causal effect of GORD on IPF risk and of IPF on GORD risk, using genetic data from the largest GORD (78 707 cases and 288 734 controls) and IPF (4125 cases and 20 464 controls) genome-wide association meta-analyses currently available.ResultsGORD increased the risk of IPF, with an OR of 1.6 (95% CI 1.04–2.49; p=0.032). There was no evidence of a causal effect of IPF on the risk of GORD, with an OR of 0.999 (95% CI 0.997–1.000; p=0.245).ConclusionsWe found that GORD increases the risk of IPF, but found no evidence that IPF increases the risk of GORD. GORD should be considered in future studies of IPF risk and interest in it as a potential therapeutic target should be renewed. The mechanisms underlying the effect of GORD on IPF should also be investigated.

Rationale: The natural history of recovery from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains unknown. Because fibrosis with persistent physiological deficit is a previously described feature of patients recovering from similar coronaviruses, treatment represents an early opportunity to modify the disease course, potentially preventing irreversible impairment. Objectives: Determine the incidence of and describe the progression of persistent inflammatory interstitial lung disease (ILD) following SARS-CoV-2 when treated with prednisolone. Methods: A structured assessment protocol screened for sequelae of SARS-CoV-2 pneumonitis. Eight hundred thirty-seven patients were assessed by telephone 4 weeks after discharge. Those with ongoing symptoms had outpatient assessment at 6 weeks. Thirty patients diagnosed with persistent interstitial lung changes at a multidisciplinary team meeting were reviewed in the interstitial lung disease service and offered treatment. These patients had persistent, nonimproving symptoms. Results: At 4 weeks after discharge, 39% of patients reported ongoing symptoms (325/837) and were assessed. Interstitial lung disease, predominantly organizing pneumonia, with significant functional deficit was observed in 35/837 survivors (4.8%). Thirty of these patients received steroid treatment, resulting in a mean relative increase in transfer factor following treatment of 31.6% (standard deviation [SD] ± 27.6, P

The last decade of research has revolutionized our understanding of respiratory microbiology, revealing that the lungs and airways contain diverse and dynamic microbial communities in health and disease. This “respiratory ecosystem”—a densely interconnected environment of microbial and host interactions—represents a tremendous and under-appreciated source of biological and clinical heterogeneity across patients with acute and chronic lung disease. Unlike other major sources of heterogeneity, such as comorbidities and host genetics, the respiratory microbiome is readily modifiable by clinical interventions, and therefore represents an untapped opportunity for therapeutic manipulation. As a potential “treatable trait” in efforts to subphenotype patients and deliver precision medicine, the respiratory microbiome is a promising therapeutic target. In this Pulmonary Perspective, we identify and discuss multiple challenges, both conceptual and practical, that must be overcome before the respiratory microbiome can be effectively modulated as a therapeutic target. Barriers include: 1) the need to identify specific microbiologic and ecologic “targets” for therapeutic modulation; 2) the need for an improved understanding of the efficacy and persistence of response to respiratory microbiome-modulating interventions; 3) the need for clinicians to be able to access, understand and utilize microbiome data for sub-phenotyping patients, and 4) specific concerns in special populations (including children, patients with chronic lung disease, and critically ill patients). By delineating these barriers, we identify opportunities for prospective research to advance our understanding of the respiratory microbiome, its role in human respiratory disease, and its genuine potential as a therapeutic target.

RationaleIdiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by limited treatment options and high mortality. Novel therapies and prognostic biomarkers are needed.ObjectiveTo identify and validate molecular determinants of IPF survival.MethodsA staged genome-wide association study (GWAS) was performed using paired genomic and survival data. Stage I cases were drawn from centers across the US and Europe and stage II cases from Vanderbilt University. Cox proportional hazards regression was used to identify gene variants associated with differential transplant-free survival (TFS). Stage I variants with nominal significance (p−5) were advanced for stage II testing and meta-analyzed to identify those reaching genome-wide significance (p−8). Downstream analyses were performed for genes and proteins associated with variants reaching genome-wide significance.Main ResultsAfter quality controls, 1481 stage I cases and 397 stage II cases were included in the analysis. After filtering, 9,075,629 variants were tested in stage I, with 158 meeting advancement criteria. Four variants associated with TFS with consistent effect direction were identified in stage II, including one in an intron of proprotein convertase subtilisin/kexin type 6 (PCSK6) reaching genome-wide significance (HR 4.11; 95%CI 2.54-6.67; p=9.45×10−9). PCSK6 protein was highly expressed in IPF lung parenchyma and negatively correlated with survival. Peripheral blood PCSK6 gene expression and plasma concentration were associated with reduced transplant-free survival.ConclusionsWe identified four novel variants associated with IPF survival, including one in PCSK6 that reached genome-wide significance. Downstream analyses suggested that PCSK6 protein may serve as prognostic biomarker in IPF and potential therapeutic target.

Background: rituximab is often used as rescue therapy in interstitial lung disease (ILD) associated with connective tissue disease (CTD), but has not been studied in clinical trials. This study aimed to assess whether rituximab is superior to cyclophosphamide as a treatment for severe or progressive CTD associated ILD.Methods: we conducted a randomised, double-blind, double-dummy, phase 2b trial to assess the superiority of rituximab compared with cyclophosphamide. Patients aged 18-80 years with severe or progressive ILD related to scleroderma, idiopathic inflammatory myositis, or mixed CTD, recruited across 11 specialist ILD or rheumatology centres in the UK, were randomly assigned (1:1) to receive rituximab (1000 mg at weeks 0 and 2 intravenously) or cyclophosphamide (600 mg/m2 body surface area every 4 weeks intravenously for six doses). The primary endpoint was rate of change in forced vital capacity (FVC) at 24 weeks compared with baseline, analysed using a mixed-effects model with random intercepts, adjusted for baseline FVC and CTD type. Prespecified secondary endpoints reported in this Article were change in FVC at 48 weeks versus baseline; changes from baseline in 6 min walk distance, diffusing capacity of the lung for carbon monoxide (DLCO), physician-assessed global disease activity (GDA) score, and quality-of-life scores on the St George's Respiratory Questionnaire (SGRQ), King's Brief Interstitial Lung Disease (KBILD) questionnaire, and European Quality of Life Five-Dimension (EQ-5D) questionnaire at 24 and 48 weeks; overall survival, progression-free survival, and time to treatment failure; and corticosteroid use. All endpoints were analysed in the modified intention-to-treat population, which comprised all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov (NCT01862926).Findings: between Dec 1, 2014, and March 31, 2020, we screened 145 participants, of whom 101 participants were randomly allocated: 50 (50%) to receive cyclophosphamide and 51 (50%) to receive rituximab. 48 (96%) participants in the cyclophosphamide group and 49 (96%) in the rituximab group received at least one dose of treatment and were included in analyses; 43 (86%) participants in the cyclophosphamide group and 42 (82%) participants in the rituximab group completed 24 weeks of treatment and follow-up. At 24 weeks, FVC was improved from baseline in both the cyclophosphamide group (unadjusted mean increase 99 mL [SD 329]) and the rituximab group (97 mL [234]); in the adjusted mixed-effects model, the difference in the primary endpoint at 24 weeks was -40 mL (95% CI -153 to 74; p=0·49) between the rituximab group and the cyclophosphamide group. KBILD quality-of-life scores were improved at 24 weeks by a mean 9·4 points (SD 20·8) in the cyclophosphamide group and 8·8 points (17·0) in the rituximab group. No significant differences in secondary endpoints were identified between the treatment groups, with the exception of change in GDA score at week 48, which favoured cyclophosphamide (difference 0·90 [95% CI 0·11 to 1·68]). Improvements in lung function and respiratory-related quality-of-life measures were observed in both treatment groups. Lower corticosteroid exposure over 48 weeks of follow-up was recorded in the rituximab group. Two (4%) of 48 participants who received cyclophosphamide and three (6%) of 49 who received rituximab died during the study, all due to complications of CTD or ILD. Overall survival, progression-free survival, and time to treatment failure did not significantly differ between the two groups. All participants reported at least one adverse event during the study. Numerically fewer adverse events were reported by participants receiving rituximab (445 events) than those receiving cyclophosphamide (646 events). Gastrointestinal and respiratory disorders were the most commonly reported adverse events in both groups. There were 62 serious adverse events of which 33 occurred in the cyclophosphamide group and 29 in the rituximab group.Interpretation: rituximab was not superior to cyclophosphamide to treat patients with CTD-ILD, although participants in both treatment groups had increased FVC at 24 weeks, in addition to clinically important improvements in patient-reported quality of life. Rituximab was associated with fewer adverse events. Rituximab should be considered as a therapeutic alternative to cyclophosphamide in individuals with CTD-ILD requiring intravenous therapy.Funding: efficacy and Mechanism Evaluation Programme (Medical Research Council and National Institute for Health Research, UK).

The respiratory tract surface is protected from inhaled pathogens by a secreted layer of mucus rich in mucin glycoproteins. Abnormal mucus accumulation is a cardinal feature of chronic respiratory diseases but the relationship between mucus and pathogens during exacerbations is poorly understood. We identified elevations in airway MUC5AC and MUC5B concentrations during spontaneous and experimentally-induced chronic obstructive pulmonary disease (COPD) exacerbations. MUC5AC was more sensitive to changes in expression during exacerbation and was therefore more predictably associated with virus load, inflammation, symptom severity, decrements in lung function, and secondary bacterial infections. MUC5AC was functionally related to inflammation as Muc5ac-deficient (Muc5ac-/-) mice had attenuated rhinovirus (RV)-induced airway inflammation and exogenous MUC5AC glycoprotein administration augmented inflammatory responses and increased release of extracellular adenosine triphosphate (ATP) in mice and human airway epithelial cell cultures. Hydrolysis of ATP suppressed MUC5AC augmentation of rhinovirus-induced inflammation in mice. Therapeutic suppression of mucin production using an epidermal growth factor receptor (EGFR) antagonist ameliorated immunopathology in a mouse COPD exacerbation model. The coordinated virus induction of MUC5AC and MUC5B suggests that non-Th2 mechanisms trigger mucin hypersecretion during exacerbations. Our data identifies a pro-inflammatory role for MUC5AC during viral infection and suggest that MUC5AC inhibition may ameliorate COPD exacerbations.

BackgroundEarly studies of veno-venous extracorporeal membrane oxygenation (VV-ECMO) in COVID-19 have revealed similar outcomes to historical cohorts. Changes in the disease and treatments has led to differences in the patients supported on VV-ECMO in the 1st and 2nd waves. We aimed to compare these two groups in both the acute and follow-up phase.MethodsIn this retrospective study, we identified the differences between patients supported on ECMO for COVID-19 between wave 1 (17/03/2020-31/08/2020) and wave 2 (01/09/2020-25/05/2021). We examined mortality at censoring date (30/11/2021) and decannulation, patient characteristics, complications and lung function and quality of life (QOL – by EQ5D3L) at first follow-up.FindingsOne-hundred and twenty-three patients were included in our analysis. Survival at censoring date [Chi-sqaured 6.35, p=0.012] and decannulation [90.4% vs 70.0%, pnd wave, whilst duration of ECMO run was longer [12.0(18.0-30.0) days vs. 29.5(15.5-58.3)] days (p=0.005)). Wave 2 patients had longer application of non-invasive ventilation (NIV) prior to ECMO and a higher incidence of barotrauma. Patient age and NIV use were independently associated with increased mortality [OR 1.07(1.01-1.14), p=0.025 and 3.37(1.12–12.60), p=0.043 respectively]. QOL and lung function, apart from KCOc was similar at follow up across the waves.ConclusionMost patients with COVID-19 supported on ECMO in both waves survived in the short and longer term. At follow-up patients had similar lung function and QOL across the 2 waves. This suggests that ECMO has an ongoing role in the management of a carefully selected group of patients with COVID-19.Trial RegistrationResearch Ethics Committee (20/EM/0204)

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a progressive and inevitably fatal condition for which there are a lack of effective biomarkers to guide therapeutic decision making. OBJECTIVES: To determine the relationship between serum concentrations of the cytokeratin fragment CYFRA 21-1 and disease progression and mortality in individuals with IPF enrolled in the Prospective Observation of Fibrosis in the Lung Clinical Endpoints (PROFILE) study. METHODS: CYFRA 21-1 was identified by immunohistochemistry in samples of human lung obtained at surgery. Concentrations of CYFRA 21-1 were measured using an ELISA-based assay in serum samples collected at baseline, 1 month, and 3 months from 491 individuals with an incident diagnosis of IPF who were enrolled in the PROFILE study and from 100 control subjects at baseline. Study subjects were followed for a minimum of 3 years after their first blood draw. MEASUREMENTS AND MAIN RESULTS: CYFRA 21-1 localizes to hyperplastic epithelium in IPF lung tissue. Peripheral CYFRA 21-1 concentrations were significantly higher in subjects with IPF than in healthy control subjects in both the discovery (n = 132) (control: 0.96 ± 0.81 ng/ml; vs. IPF: 2.34 ± 2.15 ng/ml; P

Background and objective The course of systemic sclerosis-associated interstitial lung disease (SSc-ILD) is highly variable, and accurate prognostic markers are needed. KL-6 is a mucin-like glycoprotein (MUC1) expressed by type II pneumocytes, while CYFRA 21-1 is expressed by alveolar and bronchiolar epithelial cells. Both are released into the blood from cell injury. Methods Serum KL-6 and CYFRA 21-1 levels were measured in a retrospective (n = 189) and a prospective (n = 118) cohort of SSc patients. Genotyping of MUC1 rs4072037 was performed. Linear mixed-effect models were used to evaluate the relationship with change in lung function parameters over time, while association with survival was evaluated with Cox proportional hazard analysis. Results In both cohorts, KL-6 and CYFRA 21-1 were highest in patients with lung involvement, and in patients with extensive rather than limited ILD. KL-6 was higher in patients carrying the MUC1 rs4072037 G allele in both cohorts. In patients with SSc-ILD, serum KL-6, but not CYFRA 21-1, was significantly associated with DLCO decline in both cohorts (P = 0.001 and P = 0.004, respectively), and with FVC decline in the retrospective cohort (P = 0.005), but not the prospective cohort. When combining the cohorts and subgrouping by severity (median CPI = 45.97), KL-6 remained predictive of decline in DLCO in both milder (P = 0.007) and more severe disease (P = 0.02) on multivariable analysis correcting for age, gender, ethnicity, smoking history and MUC1 allele carriage. Conclusion Our results suggest serum KL-6 predicts decline in lung function in SSc, suggesting its clinical utility in risk stratification for progressive SSc-ILD.

AIMS: Nuclear grade has been recently validated as a powerful prognostic tool in epithelioid malignant pleural mesothelioma (E-MPM). In other studies histological parameters including pleomorphic features and growth patterns were also shown to exert prognostic impact. The primary aims of our study are (1) externally validate the prognostic role of pleomorphic features in E-MPM and (2) investigate if evaluating growth pattern in addition to 2-tier nuclear grade improves prognostication. METHODS AND RESULTS: 614 consecutive cases of E-MPM from our institution over a period of 15 years were retrospectively reviewed, of which 51 showed pleomorphic features. E-MPM with pleomorphic features showed significantly worse overall survival compared those without (5.4 months vs 14.7 months). Tumours with predominantly micropapillary pattern showed the worst survival (6.2 months) followed by solid (10.5 months), microcystic (15.3 months), discohesive (16.1 months), trabecular (17.6 months) and tubulo-papillary (18.6 months). Sub-classification of growth patterns into high grade (solid, micropapillary) and low grade (all others) led to good separation of overall survival (10.5 months vs. 18.0 months) but did not predict survival independent of 2-tier nuclear grade. A composite score comprised of growth pattern and 2-tier nuclear grade did not improve prognostication compared with nuclear grade alone. Intra-tumoural heterogeneity in growth patterns is ubiquitous. CONCLUSIONS: Our findings support the incorporation of E-MPM with pleomorphic features in the epithelioid subtype as a highly aggressive variant distinct from 2-tier nuclear grade. E-MPM demonstrates extensive heterogeneity in growth pattern but its evaluation does not offer additional prognostic utility to 2-tier nuclear grade.