Predicting survival in idiopathic pulmonary fibrosis: scoring system and survival model

KL-6 as an Immunological Biomarker Predicts the Severity, Progression, Acute Exacerbation, and Poor Outcomes of Interstitial Lung Disease: A Systematic Review and Meta-Analysis

Object

Interstitial lung disease (ILD) is a specific form of chronic fibrosing interstitial pneumonia with various etiology. The severity and progression of ILD usually predict the poor outcomes of ILD. Otherwise, Krebs von den Lungen-6 (KL-6) is a potential immunological biomarker reflecting the severity and progression of ILD. This meta-analysis is to clarify the predictive value of elevated KL-6 levels in ILD.

Method

EBSCO, PubMed, and Cochrane were systematically searched for articles exploring the prognosis of ILD published between January 1980 and April 2021. The Weighted Mean Difference (WMD) and 95% Confidence Interval (CI) were computed as the effect sizes for comparisons between groups. For the relationship between adverse outcome and elevated KL-6 concentration, Hazard Ratio (HR), and its 95%CI were used to estimate the risk factor of ILD.

Result

Our result showed that ILD patients in severe and progressive groups had higher KL-6 levels, and the KL-6 level of patients in the severe ILD was 703.41 (U/ml) than in mild ILD. The KL-6 level in progressive ILD group was 325.98 (U/ml) higher than that in the non-progressive ILD group. Secondly, the KL-6 level of patients in acute exacerbation (AE) of ILD was 545.44 (U/ml) higher than stable ILD. Lastly, the higher KL-6 level in ILD patients predicted poor outcomes. The KL-6 level in death of ILD was 383.53 (U/ml) higher than in survivors of ILD. The pooled HR (95%CI) about elevated KL-6 level predicting the mortality of ILD was 2.05 (1.50–2.78), and the HR (95%CI) for progression of ILD was 1.98 (1.07–3.67).

Conclusion

The elevated KL-6 level indicated more severe, more progressive, and predicted the higher mortality and poor outcomes of ILD.

Conditioned medium from a human adipose-derived stem cell line ameliorates inflammation and fibrosis in a lung experimental model of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis is a chronic, progressive parenchymal lung disease that results in fibrogenesis and the conditioned medium from adipose-derived mesenchymal stem cells (CM-ADSCs) has been shown to be efficacious in pulmonary fibrosis animal models. The aim of the present study is to evaluate the effect of CM-ADSCs on lung inflammation and fibrosis in a Bleomycin (BLM)-induced pulmonary fibrosis model. CM-ADSCs safety and toxicity were evaluated in Sprague Dawley rats and no adverse effects were observed. Six-week-old female C57BL/6J mice were employed in the BLM-induced pulmonary fibrosis model and were divided into four groups: Group 1 (Sham): animals were kept without BLM and treatment, Group 2 (Control): BLM with vehicle DMEM, Group 3: 10 μg/kg CM-ADSCs and Group 4: 100 μg/kg CM-ADSCs. Body weight, fibrosis and inflammation histological analyses, mRNA and protein pro-inflammatory cytokine, and total hydroxyproline content calculation were performed in all groups upon sacrifice. The 100 μg/kg CM-ADSCs showed a significant increase in mean body weight compared to Controls. CM-ADSCs doses resulted in the amelioration of fibrosis, as seen by Masson's Trichrome-staining, Ashcroft scoring, and Sirius red-staining. Compared to Controls, inflammation was also significantly reduced in CM-ADSCs-treated mice, with reduced F4/80 macrophage antigen staining, TNF-α mRNA and IL-6 and IL-10 protein levels. Total hydroxyproline content was found significantly reduced in both groups of CM-ADSCs-treated mice. Overall, our study shows that the CM-ADSCs is safe and efficient against pulmonary fibrosis, as it significantly reduced inflammation and fibrosis, with the larger dose of 100 μg/kg CM-ADSCs being the most efficient one.

CD247, a Potential T Cell-Derived Disease Severity and Prognostic Biomarker in Patients With Idiopathic Pulmonary Fibrosis

Background

Idiopathic pulmonary fibrosis (IPF) has high mortality worldwide. The CD247 molecule (CD247, as known as T-cell surface glycoprotein CD3 zeta chain) has been reported as a susceptibility locus in systemic sclerosis, but its correlation with IPF remains unclear.

Methods

Datasets were acquired by researching the Gene Expression Omnibus (GEO). CD247 was identified as the hub gene associated with percent predicted diffusion capacity of the lung for carbon monoxide (Dlco% predicted) and prognosis according to Pearson correlation, logistic regression, and survival analysis.

Results

CD247 is significantly downregulated in patients with IPF compared with controls in both blood and lung tissue samples. Moreover, CD247 is significantly positively associated with Dlco% predicted in blood and lung tissue samples. Patients with low-expression CD247 had shorter transplant-free survival (TFS) time and more composite end-point events (CEP, death, or decline in FVC >10% over a 6-month period) compared with patients with high-expression CD247 (blood). Moreover, in the follow-up 1st, 3rd, 6th, and 12th months, low expression of CD247 was still the risk factor of CEP in the GSE93606 dataset (blood). Thirteen genes were found to interact with CD247 according to the protein-protein interaction network, and the 14 genes including CD247 were associated with the functions of T cells and natural killer (NK) cells such as PD-L1 expression and PD-1 checkpoint pathway and NK cell-mediated cytotoxicity. Furthermore, we also found that a low expression of CD247 might be associated with a lower activity of TIL (tumor-infiltrating lymphocytes), checkpoint, and cytolytic activity and a higher activity of macrophages and neutrophils.

Conclusion

These results imply that CD247 may be a potential T cell-derived disease severity and prognostic biomarker for IPF.

Warfarin Use Is Associated with Increased Mortality at One Year in Patients with Idiopathic Pulmonary Fibrosis

Objectives

We studied the safety and efficacy of warfarin compared to direct acting oral anticoagulant use in patients with IPF.

Methods

We conducted a retrospective cohort study of all patients with IPF who were prescribed warfarin or direct acting oral anticoagulants (DOACs) for cardiac or thromboembolic indications and followed at our institute for their care. Univariate tests and multivariable logistic regression analyses were used for assessing association of variables with outcomes.

Results

A total of 73 patients were included in the study with 28 and 45 patients in the warfarin and DOAC groups, respectively. Univariable analysis revealed a significant difference in mortality in one year between warfarin and DOAC groups (7/28 vs. 3/45, p value 0.027). Significantly more patients in the warfarin group suffered an exacerbation that required hospitalization within one year (9/28 vs. 5/45, p value 0.026). Multivariate logistic regression analysis showed that anticoagulation with warfarin was independently associated with mortality at one-year follow-up (OR: 77.4, 95% CI: 5.94–409.3, p value: 0.007).

Conclusion

In our study of patients with IPF requiring anticoagulants, we noted statistically significant higher mortality with warfarin anticoagulation when compared to DOAC use. Further larger prospective studies are needed to confirm these findings.

Molecular Mechanisms and Cellular Contribution from Lung Fibrosis to Lung Cancer Development

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrosing interstitial lung disease (ILD) of unknown aetiology, with a median survival of 2-4 years from the time of diagnosis. Although IPF has unknown aetiology by definition, there have been identified several risks factors increasing the probability of the onset and progression of the disease in IPF patients such as cigarette smoking and environmental risk factors associated with domestic and occupational exposure. Among them, cigarette smoking together with concomitant emphysema might predispose IPF patients to lung cancer (LC), mostly to non-small cell lung cancer (NSCLC), increasing the risk of lung cancer development. To this purpose, IPF and LC share several cellular and molecular processes driving the progression of both pathologies such as fibroblast transition proliferation and activation, endoplasmic reticulum stress, oxidative stress, and many genetic and epigenetic markers that predispose IPF patients to LC development. Nintedanib, a tyrosine-kinase inhibitor, was firstly developed as an anticancer drug and then recognized as an anti-fibrotic agent based on the common target molecular pathway. In this review our aim is to describe the updated studies on common cellular and molecular mechanisms between IPF and lung cancer, knowledge of which might help to find novel therapeutic targets for this disease combination.

Animal models of drug-induced pulmonary fibrosis: an overview of molecular mechanisms and characteristics

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease characterized by progressive loss of pulmonary function. Drug-induced interstitial lung disease has been reported as a severe adverse effect of some drugs, such as bleomycin, amiodarone, and methotrexate. Based on good characteristics, drug-induced pulmonary fibrosis (PF) animal model has played a key role in our understanding of the molecular mechanisms of PF pathogenesis and recapitulates the specific pathology in patients and helps develop therapeutic strategies. Here, we summarize the mechanisms and characteristics of given fibrotic drug-induced animal models for PFs. Together with the key publications describing these models, this brief but detailed overview would be helpful for the pharmacological research with animal models of PFs. Potential mechanisms underlying drug induced lung toxicity.

Decline in Mast Cell Density During Diffuse Alveolar Damage in Idiopathic Pulmonary Fibrosis

Mast cells (MCs) are known to be involved in the pathogenesis of idiopathic pulmonary fibrosis (IPF), although their role in acute exacerbations of IPF has not been investigated. The aims of the study were to evaluate the numbers of MCs in fibrotic and non-fibrotic areas of lung tissue specimens of idiopathic pulmonary fibrosis (IPF) patients with or without an acute exacerbation of IPF, and to correlate the MC density with clinical parameters. MCs of IPF patients were quantified from surgical lung biopsy (SLB) specimens (n = 47) and lung tissue specimens taken at autopsy (n = 7). MC density was higher in the fibrotic areas of lung tissue compared with spared alveolar areas or in controls. Female gender, low diffusion capacity for carbon monoxide, diffuse alveolar damage, and smoking were associated with a low MC density. MC densities of fibrotic areas had declined significantly in five subjects in whom both SLB in the stable phase and autopsy after an acute exacerbation of IPF had been performed. There were no correlations of MC densities with survival time or future acute exacerbations. The MC density in fibrotic areas was associated with several clinical parameters. An acute exacerbation of IPF was associated with a significant decline in MC counts. Further investigations will be needed to clarify the role of these cells in IPF and in the pathogenesis of acute exacerbation as this may help to identify some potential targets for medical treatment for this serious disease.

Biomarker signatures for progressive idiopathic pulmonary fibrosis

RATIONALE

Idiopathic Pulmonary Fibrosis (IPF) is a progressive lung disease in which circulatory biomarkers has the potential for guiding management in clinical practice.

OBJECTIVES

We assessed the prognostic role of serum biomarkers in three independent IPF cohorts, the Australian IPF Registry (AIPFR), Trent Lung Fibrosis (TLF) and Prospective Observation of Fibrosis in the Lung Clinical Endpoints (PROFILE).

METHODS

In the AIPFR, candidate proteins were assessed by ELISA as well as in an unbiased proteomic approach. Least absolute shrinkage and selection operator (LASSO) regression was used to restrict the selection of markers that best accounted for the progressor phenotype at one-year in AIPFR, and subsequently prospectively selected for replication in the validation TLF cohort and assessed retrospectively in PROFILE. Four significantly replicating biomarkers were aggregated into a progression index (PI) model based on tertiles of circulating concentrations.

MAIN RESULTS

One-hundred and eighty-nine participants were included in the AIPFR cohort, 205 participants from the TLF, and 122 participants from the PROFILE cohorts. Differential biomarker expression was observed by ELISA and replicated for osteopontin, matrix metallopeptidase-7, intercellular adhesion molecule-1 and periostin for those with a progressor phenotype at one-year. Proteomic data did not replicate. The PI in the AIPFR, TLF and PROFILE predicted risk of progression, mortality and progression-free survival. A statistical model incorporating PI demonstrated the capacity to distinguish disease progression at 12 months, which was increased beyond the clinical GAP model alone in all cohorts, and significantly so within incidence based TLF and PROFILE cohorts.

CONCLUSION

A panel of circulatory biomarkers can provide potentially valuable clinical assistance in the prognosis of IPF patients.

A Soft Voting Ensemble-Based Model for the Early Prediction of Idiopathic Pulmonary Fibrosis (IPF) Disease Severity in Lungs Disease Patients

Idiopathic pulmonary fibrosis, which is one of the lung diseases, is quite rare but fatal in nature. The disease is progressive, and detection of severity takes a long time as well as being quite tedious. With the advent of intelligent machine learning techniques, and also the effectiveness of these techniques, it was possible to detect many lung diseases. So, in this paper, we have proposed a model that could be able to detect the severity of IPF at the early stage so that fatal situations can be controlled. For the development of this model, we used the IPF dataset of the Korean interstitial lung disease cohort data. First, we preprocessed the data while applying different preprocessing techniques and selected 26 highly relevant features from a total of 502 features for 2424 subjects. Second, we split the data into 80% training and 20% testing sets and applied oversampling on the training dataset. Third, we trained three state-of-the-art machine learning models and combined the results to develop a new soft voting ensemble-based model for the prediction of severity of IPF disease in patients with this chronic lung disease. Hyperparameter tuning was also performed to get the optimal performance of the model. Fourth, the performance of the proposed model was evaluated by calculating the accuracy, AUC, confusion matrix, precision, recall, and F1-score. Lastly, our proposed soft voting ensemble-based model achieved the accuracy of 0.7100, precision 0.6400, recall 0.7100, and F1-scores 0.6600. This proposed model will help the doctors, IPF patients, and physicians to diagnose the severity of the IPF disease in its early stages and assist them to take proactive measures to overcome this disease by enabling the doctors to take necessary decisions pertaining to the treatment of IPF disease.

Remote Assessment of Lung Disease and Impact on Physical and Mental Health (RALPMH): Protocol for a Prospective Observational Study

BACKGROUND

Chronic lung disorders like chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) are characterized by exacerbations. They are unpleasant for patients and sometimes severe enough to cause hospital admission and death. Moreover, due to the COVID-19 pandemic, vulnerable populations with these disorders are at high risk, and their routine care cannot be done properly. Remote monitoring offers a low cost and safe solution for gaining visibility into the health of people in their daily lives, making it useful for vulnerable populations.

OBJECTIVE

The primary objective is to assess the feasibility and acceptability of remote monitoring using wearables and mobile phones in patients with pulmonary diseases. The secondary objective is to provide power calculations for future studies centered around understanding the number of exacerbations according to sample size and duration.

METHODS

Twenty participants will be recruited in each of three cohorts (COPD, IPF, and posthospitalization COVID). Data collection will be done remotely using the RADAR-Base (Remote Assessment of Disease And Relapse) mobile health (mHealth) platform for different devices, including Garmin wearable devices and smart spirometers, mobile app questionnaires, surveys, and finger pulse oximeters. Passive data include wearable-derived continuous heart rate, oxygen saturation, respiration rate, activity, and sleep. Active data include disease-specific patient-reported outcome measures, mental health questionnaires, and symptom tracking to track disease trajectory. Analyses will assess the feasibility of lung disorder remote monitoring (including data quality, data completeness, system usability, and system acceptability). We will attempt to explore disease trajectory, patient stratification, and identification of acute clinical events such as exacerbations. A key aspect is understanding the potential of real-time data collection. We will simulate an intervention to acquire responses at the time of the event to assess model performance for exacerbation identification.

RESULTS

The Remote Assessment of Lung Disease and Impact on Physical and Mental Health (RALPMH) study provides a unique opportunity to assess the use of remote monitoring in the evaluation of lung disorders. The study started in the middle of June 2021. The data collection apparatus, questionnaires, and wearable integrations were setup and tested by the clinical teams prior to the start of recruitment. While recruitment is ongoing, real-time exacerbation identification models are currently being constructed. The models will be pretrained daily on data of previous days, but the inference will be run in real time.

CONCLUSIONS

The RALPMH study will provide a reference infrastructure for remote monitoring of lung diseases. It specifically involves information regarding the feasibility and acceptability of remote monitoring and the potential of real-time data collection and analysis in the context of chronic lung disorders. It will help plan and inform decisions in future studies in the area of respiratory health.

TRIAL REGISTRATION

ISRCTN Registry ISRCTN16275601; https://www.isrctn.com/ISRCTN16275601.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/28873.

The Aggregate Index of Systemic Inflammation (AISI): A Novel Prognostic Biomarker in Idiopathic Pulmonary Fibrosis

Variable patterns of disease progression are typically observed in patients with idiopathic pulmonary fibrosis (IPF). We sought to determine the prognostic capacity of blood cell count indexes, derived from routine complete blood cell (CBC) count, in a cohort of IPF patients. The neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic inflammation index (SII), systemic inflammation response index (SIRI), and aggregate index of systemic inflammation (AISI) were calculated at baseline in a consecutive series of 82 IPF patients followed for four years. After adjusting for age, gender, body mass index, smoking status, and disease stage, only the AISI was significantly associated with mortality (HR 1.0013, 95% CI 1.0003–1.0023, p = 0.015). Patients with AISI <434 and ≥434 had a median survival from the diagnosis of 35.3 ± 15.2 and 26.6 ± 16.3 months (p = 0.015), and a four-year survival rate of 54% and 34%, respectively. The AISI, easily derivable from routine laboratory tests, is independently associated with mortality in patients with IPF. Prospective studies in larger cohorts are required to confirm this association.

A New Tool to Assess Quality of Life in Patients with Idiopathic Pulmonary Fibrosis or Non-specific Interstitial Pneumonia

Background  Quality of life (QoL) is significantly impaired in patients with pulmonary fibrosis, however reliable tools to assess QoL issues specific for this group of patients are still missing. We thus aimed to develop a new questionnaire called “Quality of life in patients with idiopathic pulmonary fibrosis” (QPF) to measure QoL in patients with fibrotic idiopathic interstitial pneumonias (IIP).

Methods  An item pool was created on the basis of a German expert group with support of patients suffering from pulmonary fibrosis. In a 1st step, this version of the questionnaire was completed by 52 patients with idiopathic pulmonary fibrosis (IPF) or non-specific interstitial pneumonia (NSIP). Following this, an item- and an exploratory factor analysis was carried out and a 2nd version created. In a multicenter validation study in a one-group pre-post design, the questionnaire was filled in by 200 patients with IIP (IPF = 190, iNSIP = 10) at 2 time points with an interval of 6 months. Cross-validation was carried out with the St. Georges Respiratory Questionnaire (SGRQ).

Results  The mean age of the patients was 71.0 years (50–90 years), 82.5 % were male. Item analysis revealed that most of Cronbach alpha and selectivity values of QPF-scales could be considered as sufficient (e. g. QPF-scale “condition” [alpha = 0.827], “impairment” [alpha = 0.882]). At scale level, there were significant differences in terms of a deterioration or improvement in the QPF-condition and QPF-breathlessness scales and also in the SGRQ-activity scale. Analysis of construct validation of QPF and SGRQ showed moderate correlations between both questionnaires. A deterioration in health status from the patient’s and doctorʼs perspective was seen in the scales “impairment”, “shortness of breath” and “health status” of the QPF. The QPF was able to detect a change in the patientʼs mood (“condition” scale) in the course of treatment.

Conclusion  This newly developed questionnaire maps the special needs of the patients well. The QPF is suitable for screening of quality of life as well as for supplementing the medical history and for monitoring the course of disease in fibrotic IIPs.

Characteristics and mortality in primary Sjögren syndrome-related interstitial lung disease

ABSTRACT

Aim of the study was to determine the characteristics and prognosis, and to identify the risk factors for mortality in patients with primary Sjögren syndrome (pSS) with interstitial lung disease (pSS-ILD).A total of 1422 patients with SS were screened and 178 patients with pSS-ILD were recruited. The medical records and outcomes were retrospectively reviewed. Overall survival and case control study were performed to explore the predictors of death.Among 178 pSS-ILD patients, 87.1% were women. Mean age was 61.59 ± 11.69-year-old. Median disease duration was 72.0 (24.0, 156.0) months. Nonspecific interstitial pneumonia was the predominant high-resolution computed tomography pattern (44.9%). Impairment in diffusion capacity was the most common abnormality of pulmonary function test (75.8%) and the most severe consequence. Type 1 respiratory failure and hypoxia were observed in 15.0% and 30.0% patients, respectively. Mean survival time after confirmation of pSS-ILD diagnosis was 9.0 (6.8, 13.0) years. The 10-year survival rate for all patients with pSS-ILD was 81.7%. Forty-four (24.7%) of 178 patients died during the follow-up period. The most predominant cause of death was respiratory failure (n = 27). Twenty-seven patients died of ILD and formed study group. The 78 patients who survived formed control group. Age and smoking were risk factors for mortality in patients with pSS-ILD. In addition, severity of ILD, as reflected by high-resolution computed tomography, pulmonary function test, and arterial blood gas, was an independent risk factor. However, inflammation status (erythrocyte sedimentation rate, C-reactive protein) and anti-Sjögren syndrome-related antigen A and anti-Sjögren syndrome-related antigen B were not.ILD is a severe complication of pSS. Age, smoking, and severity of lung involvement are more critical for prognosis rather than inflammation status and autoantibodies.

Physical activity decline is disproportionate to decline in pulmonary physiology in IPF

BACKGROUND AND OBJECTIVE

Patients with idiopathic pulmonary fibrosis (IPF) have reduced levels of daily physical activity (DPA); however, little is known about how DPA changes as disease progresses. We aimed to (i) describe change in DPA over 12 months, (ii) analyse its association with conventional markers of disease severity and quality of life and (iii) assess DPA as a prognostic tool.

METHODS

A total of 54 patients with IPF had DPA monitored at baseline and at 6 and 12 months with a SenseWear armband for 7 consecutive days. Participants completed the Hospital Anxiety and Depression scale, St George's Respiratory Questionnaire and Leicester Cough Questionnaire at each time point and provided clinical data including forced vital capacity (FVC), diffusion capacity of carbon monoxide and 6-min walk distance (6MWD).

RESULTS

Baseline and 12-month daily step count (DSC) were 3887 (395) and 3326 (419), respectively. A significant reduction in DSC (mean = 645 [260], p = 0.02) and total energy expenditure (mean = 486 kJ [188], p = 0.01) was demonstrated at 12 months. The decline in DSC over 12 months was proportionally larger than decline in lung function. Annual change in DPA had weak to moderate correlation with annual change in FVC % predicted and 6MWD (range r = 0.34-0.45). Change in physical activity was not associated with long-term survival.

CONCLUSION

In IPF, decline in DPA over 12 months is significant and disproportionate to decline in pulmonary physiology and may be a useful tool for assessment of disease progression.

Early diagnosis of fibrotic interstitial lung disease: challenges and opportunities

Many patients with interstitial lung disease (ILD) develop pulmonary fibrosis, which can lead to reduced quality of life and early mortality. Patients with fibrotic ILD often have considerable diagnostic delay, and are exposed to unnecessary and costly diagnostic procedures, and ineffective and potentially harmful treatments. Non-specific and insidious presenting symptoms, along with scarce knowledge of fibrotic ILD among primary care physicians and non-ILD experts, are some of the main causes of diagnostic delay. Here, we outline and discuss the challenges facing both patients and physicians in making an early diagnosis of fibrotic ILD, and explore strategies to facilitate early identification of patients with fibrotic ILD, both in the general population and among individuals at highest risk of developing the disease. Finally, we discuss controversies and key uncertainties in screening programmes for fibrotic ILD. Timely identification and accurate diagnosis of patients with fibrotic ILD poses several substantial clinical challenges, but could potentially improve outcomes through early initiation of appropriate management.

Effect of a Patient Support Program for Idiopathic Pulmonary Fibrosis Patients on Medication Persistence: A Retrospective Database Analysis

INTRODUCTION

In 2015, Boehringer Ingelheim (BI) created a support program for patients with idiopathic pulmonary fibrosis (IPF) treated with nintedanib, to help patients obtain their prescription, learn about their disease and medication, and provide support in the management of their IPF. The purpose of this study was to measure the impact of the program on nintedanib persistence among patients with IPF newly treated with the medication.

METHODS

A retrospective cohort analysis of BI Pharmaceuticals, Inc.'s Specialty Pharmacy (SP) database was conducted. Patients at least 18 years of age, newly treated with nintedanib from April 1, 2015 to January 31, 2018, and with at least one diagnosis of IPF were included in the study; earliest nintedanib prescription was the index date. Patients were classified into two mutually exclusive cohorts: enrolled in the patient support program within 60 days of index or not enrolled in the program at any time. The cohorts were compared in terms of patient characteristics, time to nintedanib discontinuation (a gap of more than 60 days between refills), and proportion of persistent patients at 6, 12, 18, and 24 months after index. Time to discontinuation was compared between the cohorts using Kaplan-Meier analysis. A multivariable Cox proportional hazards model assessed the impact of program participation on time to discontinuation within the first 12 months.

RESULTS

A total of 3114 enrolled and 9388 non-enrolled patients were identified. The proportion of patients persistent on nintedanib was higher among enrolled patients throughout the post-index period (57.8% vs. 49.7% at 6 months, 34.7% vs. 28.9% at 12 months; p < 0.05). In adjusted analyses, being enrolled in the program was associated with a 21% decreased hazard of discontinuing nintedanib over the first-year post-index [hazard ratio (HR) = 0.79, 95% CI 0.75-0.83, p < 0.05).

CONCLUSION

Real-world evidence suggests a persistence benefit for patients with IPF treated with nintedanib who are enrolled in the patient support program.

Cicatricial organizing pneumonia associated with fibrosing interstitial pneumonia - A clinicopathological study

BACKGROUND

The recent recognition of the cicatricial organizing pneumonia (ciOP) indicates that the ciOP may resemble or simulate fibrotic interstitial pneumonia; however, there has been great uncertainty regarding the affected populations, pathogenesis, clinical relevance, and characteristics. In this study, we compared the characteristics of fibrotic interstitial pneumonia with and without ciOP.

METHOD

We enrolled 121 patients from the consultation archive whose pathological findings were fibrotic interstitial pneumonia and for whom follow-up clinical data were available. We reviewed these cases histopathologically and classified them according to whether or not they showed ciOP. We compared the clinicopathological features between the two groups.

RESULT

CiOP histopathologically characterized by deposition of dense collagenous fibers within the alveolar space without destruction of the lung structure was found in 48 patients (39.7%). None of the cases with ciOP experienced acute exacerbation during 12 months follow-up. The group with ciOP had more severe diffusion impairment but this, along with restrictive ventilatory impairment, improved significantly compared to the group without ciOP.

CONCLUSION

CiOP is a histopathological finding commonly found in fibrotic interstitial pneumonia. It does not relate to acute exacerbation or decrease in pulmonary function.

Prognostic value of 6-min walk stress echocardiography in patients with interstitial lung disease

BACKGROUND

The 6-min walk test (6MWT) provides prognostic information for patients with interstitial lung disease (ILD). Parameter determined by Doppler echocardiography after the 6MWT (6 MW stress echocardiography) is shown to be a predictor of future development of pulmonary hypertension in patients with connective tissue disease. However, the clinical utility of 6 MW stress echocardiography in predicting cardiopulmonary events in patients with ILD remains unknown. We examined whether parameters determined by 6 MW stress echocardiography independent predictors of adverse events in patients with ILD.

METHODS

Echocardiographic examinations were performed in 68 consecutively enrolled patients with ILD (age, 65 ± 10 years, 65% men). A pressure gradient of tricuspid regurgitation (TRPG) and pulmonary vascular resistance (PVRecho) calculated using the following formula [PVRecho = (peak velocity of TR × 10/time-velocity integral of right ventricular outflow (RVOT-VTI)) + 0.16] were measured at baseline and at post 6MWT. Data for parameters of pulmonary functional tests and for 6MWT were collected.

RESULTS

During a mean follow-up period of 22 ± 12 months, 22 patients experienced cardiopulmonary events. In univariate analysis, %VC, TRPG, PVRecho, TRPG post 6MWT, and PVRecho post 6MWT were significantly associated with cardiopulmonary events. Multivariate analysis using the Cox proportional hazards model indicated that %VC [hazard ratio (HR): 0.97, p = 0.009] and PVRecho post 6MWT (HR: 1.77, p = 0.004) were independent predictors of cardiopulmonary events in patients with ILD.

CONCLUSIONS

In addition to parameters of pulmonary function tests, increased PVRecho post 6MWT is a significant predictor of cardiopulmonary events in patients with ILD. A 6 MW stress echocardiography is useful in assessing the risk of adverse events in patients with ILD.

The Value of the Surprise Question to Predict One-Year Mortality in Idiopathic Pulmonary Fibrosis: A Prospective Cohort Study

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive fatal disease with a heterogeneous disease course. Timely initiation of palliative care is often lacking. The surprise question "Would you be surprised if this patient died within the next year?" is increasingly used as a clinical prognostic tool in chronic diseases but has never been evaluated in IPF.

OBJECTIVE

We aimed to evaluate the predictive value of the surprise question for 1-year mortality in IPF.

METHODS

In this prospective cohort study, clinicians answered the surprise question for each included patient. Clinical parameters and mortality data were collected. The sensitivity, specificity, accuracy, negative, and positive predictive value of the surprise question with regard to 1-year mortality were calculated. Multivariable logistic regression analysis was performed to evaluate which factors were associated with mortality. In addition, discriminative performance of the surprise question was assessed using the C-statistic.

RESULTS

In total, 140 patients were included. One-year all-cause mortality was 20% (n = 28). Clinicians identified patients with a survival of <1 year with a sensitivity of 68%, a specificity of 82%, an accuracy of 79%, a positive predictive value of 49%, and a negative predictive value of 91%. The surprise question significantly predicted 1-year mortality in a multivariable model (OR 3.69; 95% CI 1.24-11.02; p = 0.019). The C-statistic of the surprise question to predict mortality was 0.75 (95% CI 0.66-0.85).

CONCLUSIONS

The answer on the surprise question can accurately predict 1-year mortality in IPF. Hence, this simple tool may enable timely focus on palliative care for patients with IPF.

Nitrogen dioxide increases the risk of mortality in idiopathic pulmonary fibrosis

Ambient air pollution is associated with the prognosis of idiopathic pulmonary fibrosis (IPF) patients. We aimed to identify the impacts of individual exposure to particulate matter with a 50% cut-off aerodynamic diameter of 10 μm (PM₁₀) and nitrogen dioxide (NO₂) on IPF patients' mortality.1114 patients (mean age 65.7 years; male 80.5%) diagnosed with IPF between 1995 and 2016 were included in this study. Individual-level long-term concentrations of PM₁₀ and NO₂ at residential addresses of patients were estimated using a national-scale exposure prediction model. The effect of PM₁₀ and NO₂ on mortality was estimated using a Cox proportional hazards model adjusted for individual- and area-level covariates.The median follow-up period was 3.8 years and 69.5% of the patients died or underwent lung transplantation. When adjusted for individual- and area-level covariates, a 10 ppb increase in NO₂ concentration was associated with a 17% increase in mortality (hazard ratio (HR) 1.172, 95% CI 1.030-1.344; p=0.016). When IPF patients were stratified by age (≥65 versus <65 years) or by sex, NO₂ was a significant prognostic factor for mortality in the elderly (HR 1.331, 95% CI 1.010-1.598; p=0.010). When stratified by age and sex jointly, NO₂ showed the stronger association with mortality in elderly males (HR 1.305, 95% CI 1.072-1.598; p=0.008) than in other groups. PM₁₀ was not associated with IPF mortality in all patients and in subgroups stratified by age or sex.Our findings suggest that increased exposure to NO₂ can increase the risk of mortality in patients with IPF, specifically in elderly males.

Clinical and radiological criteria for the differential diagnosis between asbestosis and idiopathic pulmonary fibrosis: Application in two cases

Introduction:

Idiopathic pulmonary fibrosis (IPF) and asbestosis are pulmonary interstitial diseases that may present overlapping clinical aspects in the full-blown phase of the disease. For both clinical entities the gold standard for diagnosis is histological examination, but its execution poses ethical problems, especially when performed for preventive or forensic purposes.

Objective:

To evaluate the application of internationally accepted clinical, anamnestic and radiological criteria for differential diagnosis between asbestosis and IPF, and to assess the ability to discriminate between the two diseases. Even if clinically similar, the two diseases present extremely different prognostic and therapeutic perspectives.

Methods:

Two clinical cases of IPF are reported, in which the differential diagnosis was made by studying occupational exposure to asbestos, the onset and progression of clinical symptoms, and the identification of specific radiological elements by means of chest High Resolution Computed Tomography (HRCT).

Results:

The diagnosis of IPF could be made on the basis of the absence of significant exposure to asbestos, the early onset and rapid progression of dyspnea and restrictive ventilatory defects, in association with a pulmonary radiological pattern characterized by peculiar elements such as honeycombing.

Discussion:

The diagnostic procedure adopted to make a differential diagnosis with asbestosis provides practical clinical elements facilitating the differentiation between the two forms of pulmonary fibrosis, a fundamental aspect of the activity of the occupational physician.

Asymmetrical Interstitial Lung Disease Suggested to Be Due to Hypoplasia of the Unilateral Pulmonary Artery: A Case Report with a 20-year Follow-up

We herein report a case of asymmetrical interstitial lung disease (ILD) that remained almost completely asymmetrical over time on chest computed tomography (CT). An open lung biopsy from the right lung showed severe pleural adhesion, obstruction of the pulmonary artery, and dilated systemic arteries in addition to the usual interstitial pneumonia pattern. Three-dimensional CT angiography showed partial defects of pulmonary arteries on the affected side. After excluding other known causes of ILD and gastroesophageal reflux, we suspected that decreased pulmonary artery perfusion in the present case may have been responsible for the observed asymmetrical unilateral fibrosis.

Molecular markers of telomere dysfunction and senescence are common findings in the usual interstitial pneumonia pattern of lung fibrosis

AIMS

Idiopathic pulmonary fibrosis (IPF) is a genetically mediated, age-associated, progressive form of pulmonary fibrosis characterised pathologically by a usual interstitial pneumonia (UIP) pattern of fibrosis. The UIP pattern is also found in pulmonary fibrosis attributable to clinical diagnoses other than IPF (non-IPF UIP), whose clinical course is similarly poor, suggesting common molecular drivers. This study investigates whether IPF and non-IPF UIP lungs similarly express markers of telomere dysfunction and senescence.

METHODS AND RESULTS

To test whether patients with IPF and non-IPF UIP share molecular drivers, lung tissues from 169 IPF patients and 57 non-IPF UIP patients were histopathologically and molecularly compared. Histopathological changes in both IPF and non-IPF UIP patients included temporal heterogeneity, microscopic honeycombing, fibroblast foci, and dense collagen fibrosis. Non-IPF UIP lungs were more likely to have lymphocytic infiltration, non-caseating granulomas, airway-centred inflammation, or small airways disease. Telomeres were shorter in alveolar type II (AECII) cells of both IPF and non-IPF UIP lungs than in those of age-similar, unused donor, controls. Levels of molecular markers of senescence (p16 and p21) were elevated in lysates of IPF and non-IPF UIP lungs. Immunostaining localised expression of these proteins to AECII cells. The mucin 5B (MUC5B) gene promoter variant minor allele frequency was similar between IPF and non-IPF UIP patients, and MUC5B expression was similar in IPF and non-IPF UIP lungs.

CONCLUSIONS

Molecular markers of telomere dysfunction and senescence are pathologically expressed in both IPF and non-IPF UIP lungs. These findings suggest that common molecular drivers may contribute to the pathogenesis of UIP-associated pulmonary fibrosis, regardless of the clinical diagnosis.

High turnover of types III and VI collagen in progressive idiopathic pulmonary fibrosis

BACKGROUND AND OBJECTIVE

Prediction of idiopathic pulmonary fibrosis (IPF) progression is vital for the choice and timing of treatment and patient follow-up. This could potentially be achieved by prognostic blood biomarkers of extracellular matrix (ECM) remodelling.

METHODS

Neoepitope biomarkers of types III and VI collagen turnover (C3M, C6M, PRO-C3 and PRO-C6) were measured in 185 patients with newly diagnosed IPF. Disease severity at baseline and progression over 6 months was assessed by lung function tests and 6-min walk tests. All-cause mortality was assessed over a 3-year follow-up period.

RESULTS

High baseline levels of C3M, C6M, PRO-C3 and PRO-C6 were associated with more advanced disease at the time of diagnosis. Baseline levels of C6M and PRO-C3 were also associated with mortality over 3 years of follow-up (hazard ratio [HR]: 2.3, 95% CI: 1.3-3.9, p = 0.002 and HR: 1.8, 95% CI: 1.1-3.0, p = 0.03). Patients with several increased biomarkers at baseline, representing a high ECM remodelling phenotype, had more advanced disease at baseline, higher risk of progression or death at 6 months (OR: 1.4, 95% CI: 1.1-1.8, p = 0.002) and higher mortality over 3 years of follow-up (HR: 2.4, 95% CI: 1.3-4.5, p = 0.007).

CONCLUSION

Blood biomarkers of types III and VI collagen turnover, assessed at the time of diagnosis, are associated with several indices of disease severity, short-term progression and long-term mortality. These biomarkers can help to identify patients with a high ECM remodelling phenotype at high risk of disease progression and death.

The Emerging Role of Quantification of Imaging for Assessing the Severity and Disease Activity of Emphysema, Airway Disease, and Interstitial Lung Disease

There has been an explosion of use for quantitative image analysis in the setting of lung disease due to advances in acquisition protocols and postprocessing technology, including machine and deep learning. Despite the plethora of published papers, it is important to understand which approach has clinical validation and can be used in clinical practice. This paper provides an introduction to quantitative image analysis techniques being used in the investigation of lung disease and focusses on the techniques that have a reasonable clinical validation for being used in clinical trials and patient care.

Baseline characteristics and survival of patients of idiopathic pulmonary fibrosis: a longitudinal analysis of the Swedish IPF Registry

Background

Observational data under real-life conditions in idiopathic pulmonary fibrosis (IPF) is scarce. We explored anti-fibrotic treatment, disease severity and phenotypes in patients with IPF from the Swedish IPF Registry (SIPFR).

Methods

Patients enrolled between September 2014 and April 2020 and followed ≥ 6 months were investigated. Demographics, comorbidities, lung function, composite variables, six-minute walking test (6MWT), quality of life, and anti-fibrotic therapy were evaluated. Agreements between classification of mild physiological impairment (defined as gender-age-physiology (GAP) stage 1) with physiological and composite measures of severity was assessed using kappa values and their impact on mortality with hazard ratios. The factor analysis and the two-step cluster analysis were used to identify phenotypes. Univariate and multivariable survival analyses were performed between variables or groups.

Results

Among 662 patients with baseline data (median age 72.7 years, 74.0% males), 480 had a follow up ≥ 6 months with a 5 year survival rate of 48%. Lung function, 6MWT, age, and BMI were predictors of survival. Patients who received anti-fibrotic treatment ≥ 6 months had better survival compared to untreated patients [p = 0.007, HR (95% CI): 1.797 (1.173–2.753)] after adjustment of age, gender, BMI, smoking status, forced vital capacity (FVC) and diffusion capacity of carbon monoxide (DLCO). Patients with mild physiological impairment (GAP stage 1, composite physiological index (CPI) ≤ 45, DLCO ≥ 55%, FVC ≥ 75%, and total lung capacity (TLC) ≥ 65%, respectively) had better survival, after adjustment for age, gender, BMI and smoking status and treatment. Patients in cluster 1 had the worst survival and consisted mainly of male patients with moderate-severe disease and an increased prevalence of heart diseases at baseline; Cluster 2 was characterized by mild disease with more than 50% females and few comorbidities, and had the best survival; Cluster 3 were younger, with moderate-severe disease and had few comorbidities.

Conclusion

Disease severity, phenotypes, and anti-fibrotic treatment are closely associated with the outcome in IPF, with treated patients surviving longer. Phenotypes may contribute to predicting outcomes of patients with IPF and suggest the patients’ need for special management, whereas single or composite variables have some limitations as disease predictors.

Serial 6-month change in forced vital capacity predicts subsequent decline and mortality in Japanese patients with newly diagnosed idiopathic pulmonary fibrosis

BACKGROUND

The clinical course of idiopathic pulmonary fibrosis (IPF) is characterized by a progressive decline in lung function; however, predicting changes in lung function is difficult. We sought to determine whether the prior 6-month trend in forced vital capacity (FVC) could predict mortality and the subsequent 6-month trend in FVC.

METHODS

We retrospectively analyzed consecutive patients with newly diagnosed IPF who underwent serial pulmonary function tests. The immediate two years after the initial evaluation were divided into four terms of six months each and stratified on the basis of presence or absence of a ≥10% relative decline in FVC at six months (declined and stable groups, respectively).

RESULTS

We included 107 patients with %predicted FVC of 80.8% and %predicted diffusing capacity of the lung for carbon monoxide of 58.9%. In multivariate analysis, a decline in %predicted FVC in the initial six months was found to be an independent prognostic factor (hazard ratio 4.45, 95% confidence interval 2.62-7.56, p < 0.01). Among the 46 terms in which the FVC declined during the initial 1.5-year study period, a decline in FVC was exhibited in 23 (50.0%) of the subsequent terms. Among 231 terms in which FVC remained stable, a decline was observed in 32 (13.9%) of the subsequent terms (relative risk 3.61, p < 0.01). The frequency of FVC decline in each term was 16-27%. FVC was stable or declined in all four terms in 50.5% and 15.9% of cases, respectively.

CONCLUSIONS

Six-month decline in FVC predicts subsequent FVC change and mortality in IPF patients in the era of antifibrotic agents.

MicroRNA and protein-coding gene expression analysis in idiopathic pulmonary fibrosis yields novel biomarker signatures associated to survival

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive interstitial lung disease of unknown etiology that poses significant challenges in early diagnosis and prediction of progression. Analyses of microRNA and gene expression in IPF have yielded potentially predictive information. However, the relationship between microRNA/gene expression and quantitative phenotypic value in IPF remains controversial, as is the added value of this approach to current molecular signatures in IPF. To identify biomarkers predictive of survival in IPF via a microRNA-driven strategy. We profiled microRNA and protein-coding gene expression in peripheral blood mononuclear cells from 70 IPF subjects in a discovery cohort. We linked the microRNA/gene expression level with the quantitative phenotypic variation in IPF, including diffusing capacity of the lung for carbon monoxide and the forced vital capacity percent predicted. In silico analyses of expression profiles and quantitative phenotypic data allowed the generation of 2 sets of IPF molecular signatures (unique for microRNAs and protein-coding genes) that predict IPF survival. Each signature performed well in a validation cohort comprised of IPF patients aggregated from distinct patient populations recruited from different sites. Resampling test suggests that the protein-coding gene based signature is comparable and potentially superior to published IPF prognostic gene signatures. In conclusion, these results highlight the utility of microRNA-driven peripheral blood molecular signatures as valuable and novel biomarkers associated to individuals at high survival risk and for potentially facilitating individualized therapies in this enigmatic disorder.

IC4: a new combined predictive index of mortality in idiopathic pulmonary fibrosis

BACKGROUND

While a number of individual patient characteristics are associated with survival in idiopathic pulmonary fibrosis (IPF), their incorporation into combined indexes, such as the GAP index, has been shown to increase the predictive capacity. It is unknown whether the predictive capacity of GAP-derived indexes that also include anthropometric and exercise parameters is superior to the original instrument.

METHODS

We tested the four-year survival predictive capacity of a modified, adimensional and multiplicative GAP index (IC4) that included percent forced vital capacity (FVC%), diffusing capacity of the lung for carbon monoxide (DLCO%), body mass index (BMI), and six-minute walk distance (6MWD) in 90 IPF patients recruited from two centres in France and Italy.

RESULTS

In ROC comparisons, the AUC of the IC4 (0.859, 95% CI 0.770-0.924 p<0.0001) was significantly higher than the AUCs of the individual components, their two-three component combinations, and the original GAP index, with 77% sensitivity and 89% specificity. Mean survival was 14.0±11.7, 23.2±12.7, 34.9±14.8, and 40.8±12.9 months, and survival rate was 0%, 14%, 39% and 73%, in IC4 quartile 1, 2, 3, and 4, respectively.

CONCLUSIONS

The IC4, a combined adimensional index incorporating FVC%, DLCO%, BMI and 6MWD, provides superior capacity to predict mortality, when compared to its individual components, their other combinations, and the GAP index, in patients with IPF.

Immune dysregulation as a driver of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) affects hundreds of thousands of people worldwide, reducing their quality of life and leading to death from respiratory failure within years of diagnosis. Treatment options remain limited, with only two FDA-approved drugs available in the United States, neither of which reverse the lung damage caused by the disease or prolong the life of individuals with IPF. The only cure for IPF is lung transplantation. In this review, we discuss recent major advances in our understanding of the role of the immune system in IPF that have revealed immune dysregulation as a critical driver of disease pathophysiology. We also highlight ways in which an improved understanding of the immune system's role in IPF may enable the development of targeted immunomodulatory therapies that successfully halt or potentially even reverse lung fibrosis.

The role of interleukin-6 as a prognostic biomarker for predicting acute exacerbation in interstitial lung diseases

BACKGROUND

Interstitial lung diseases (ILDs) are chronic, parenchymal lung diseases with a variable clinical course and a poor prognosis. Within various clinical courses, acute exacerbation (AE) is a devastating condition with significant morbidity and high mortality. The aim of this study was to investigate the role of interleukin-6 (IL-6) to predict AE and prognosis in patients with ILD.

METHODS

Eighty-three patients who were diagnosed with ILD from 2016 to 2019 at the Haeundae Paik Hospital, Busan, South Korea, were included and their clinical data were retrospectively analyzed.

RESULTS

The median follow-up period was 20 months. The mean age was 68.1 years and 65.1% of the patients were men with 60.2% of patients being ever-smokers. Among ILDs, idiopathic pulmonary fibrosis was the most common disease (68.7%), followed by connective tissue disease-associated ILD (14.5%), cryptogenic organizing pneumonia (9.6%), and nonspecific interstitial pneumonia (6.0%). The serum levels of IL-6 were measured at diagnosis with ILD and sequentially at follow-up visits. During the follow-ups, 15 (18.1%) patients experienced an acute exacerbation (AE) of ILD and among them, four (26.7%) patients died. In the multivariable analysis, high levels of IL-6 (OR 1.014, 95% CI: 1.001-1.027, p = 0.036) along with lower baseline saturations of peripheral oxygen (SpO2) were independent risk factors for AE. In the receiver operating characteristic curve analysis, the area under the curve was 0.815 (p < 0.001) and the optimal cut-off value of serum IL-6 to predict AE was 25.20 pg/mL with a sensitivity of 66.7% and specificity of 80.6%. In the multivariable Cox analysis, a high level of serum IL-6 (HR 1.007, 95% CI: 1.001-1.014, p = 0.018) was only an independent risk factor for mortality in ILD patients.

CONCLUSIONS

In our study, a high level of serum IL-6 is a useful biomarker to predict AE and poor prognosis in patients with ILD.

The ER Stress/UPR Axis in Chronic Obstructive Pulmonary Disease and Idiopathic Pulmonary Fibrosis

Cellular protein homeostasis in the lungs is constantly disrupted by recurrent exposure to various external and internal stressors, which may cause considerable protein secretion pressure on the endoplasmic reticulum (ER), resulting in the survival and differentiation of these cell types to meet the increased functional demands. Cells are able to induce a highly conserved adaptive mechanism, known as the unfolded protein response (UPR), to manage such stresses. UPR dysregulation and ER stress are involved in numerous human illnesses, such as metabolic syndrome, fibrotic diseases, and neurodegeneration, and cancer. Therefore, effective and specific compounds targeting the UPR pathway are being considered as potential therapies. This review focuses on the impact of both external and internal stressors on the ER in idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) and discusses the role of the UPR signaling pathway activation in the control of cellular damage and specifically highlights the potential involvement of non-coding RNAs in COPD. Summaries of pathogenic mechanisms associated with the ER stress/UPR axis contributing to IPF and COPD, and promising pharmacological intervention strategies, are also presented.

Serum Krebs von den Lungen-6 level predicts disease progression in interstitial lung disease

Disease progression (DP) in interstitial lung disease (ILD) is variable and difficult to predict. In previous reports, serum Krebs von den Lungen-6 (KL-6) was suggested to be useful in diagnosing and predicting survival in ILD. The aim of our study was to investigate the usefulness of serum KL-6 as a predictor of DP in ILD. Clinical data of 199 patients with ILD (idiopathic pulmonary fibrosis: 22.8%) were prospectively collected and serum KL-6 levels were measured. DP was defined as a relative decline in forced vital capacity (FVC) ≥ 10%, acute exacerbation, or death during follow-up. The median follow-up period was 11.1 months. The mean age of the subjects was 62.2 years, and 59.8% were male. DP occurred in 21.6% of patients. The progressed group showed lower FVC, lower diffusing capacity for carbon monoxide, lower the minimum oxygen saturation during the 6-minute walk test, higher fibrosis scores on high-resolution computed tomography, and higher KL-6 levels (826.3 vs. 629.0 U/mL; p < 0.001) than those of the non-progressed group. In receiver operating characteristic curve analysis, serum KL-6 levels were a significant predictor of DP in ILD (area under the curve = 0.629, p = 0.009, and the optimal cut-off level was 811 U/mL). In multivariable Cox analysis, high serum KL-6 levels (≥ 800 U/mL) were only independently associated with DP in ILD (HR 2.689, 95% CI 1.445–5.004, P = 0.002). Serum KL-6 levels might be useful to predict DP in patients with ILD.

Oscillometry and computed tomography findings in patients with idiopathic pulmonary fibrosis

Although the utility of oscillometry for predicting disease severity in idiopathic pulmonary fibrosis (IPF) had been researched, little has been reported on the mechanism of why respiratory impedance reflects disease severity. In addition, traction bronchiectasis has been considered to reduce respiratory resistance and correlate negatively with airflow obstruction, but this hypothesis has not been validated. The present study aimed to investigate the correlations between oscillometric parameters and fibrosis-related lung abnormalities in IPF and to assess the utility of oscillometry as a surrogate marker for traction bronchiectasis and airflow obstruction.

Eighty Japanese patients with IPF underwent high-resolution computed tomography (HRCT), spirometry, and oscillometry and were retrospectively investigated. Fibrosis-related HRCT findings were scored regarding airspace consolidation, honeycombing, architectural distortion, traction bronchiectasis, and fibrosis. Correlations between the HRCT scores, spirometric parameters, and oscillometric parameters were analysed.

Respiratory reactance correlated positively with all fibrosis-related HRCT scores. Vital capacity and forced vital capacity (FVC) correlated negatively with oscillometric parameters and HRCT scores, reflecting the severity of restrictive ventilatory deficiency. Respiratory resistance was not related to any of the HRCT scores or forced expiratory volume in 1 s/FVC. However, forced expiratory volume in 1 s/FVC correlated positively with HRCT scores, which showed that airflow obstruction became milder as the disease progressed.

In conclusion, respiratory reactance reflects fibrosis and restrictive ventilatory deficiency in IPF. Moreover, respiratory resistance is independent of traction bronchiectasis and airflow obstruction in patients with IPF, which implies that respiratory resistance might reflect different properties of the airways.

Respiratory reactance measured by oscillometry correlates with fibrosis-related computed tomography findings in idiopathic pulmonary fibrosis (IPF). Respiratory resistance is independent of traction bronchiectasis and airflow obstruction in IPF.https://bit.ly/36zoGtf

ILDGDB: a manually curated database of genomics, transcriptomics, proteomics and drug information for interstitial lung diseases

BACKGROUND

Interstitial lung diseases (ILDs), a diverse group of diffuse lung diseases, mainly affect the lung parenchyma. The low-throughput 'omics' technologies (genomics, transcriptomics, proteomics) and relative drug information have begun to reshaped our understanding of ILDs, whereas, these data are scattered among massive references and are difficult to be fully exploited. Therefore, we manually mined and summarized these data at a database (ILDGDB, http://ildgdb.org/ ) and will continue to update it in the future.

MAIN BODY

The current version of ILDGDB incorporates 2018 entries representing 20 ILDs and over 600 genes obtained from over 3000 articles in four species. Each entry contains detailed information, including species, disease type, detailed description of gene (e.g. official symbol of gene), and the original reference etc. ILDGDB is free, and provides a user-friendly web page. Users can easily search for genes of interest, view their expression pattern and detailed information, manage genes sets and submit novel ILDs-gene association.

CONCLUSION

The main principle behind ILDGDB's design is to provide an exploratory platform, with minimum filtering and interpretation, while making the presentation of the data very accessible, which will provide great help for researchers to decipher gene mechanisms and improve the prevention, diagnosis and therapy of ILDs.

Impact of Lung Biopsy on Lung Function in Idiopathic Pulmonary Fibrosis

BACKGROUND

Video-assisted surgical lung biopsy (SLB) is performed in 10-30% of cases to establish the diagnosis of idiopathic pulmonary fibrosis (IPF).

OBJECTIVES

The aim of the study was to analyze the impact of SLB on lung function in patients eventually diagnosed with IPF.

METHODS

This is an observational, retrospective, monocentric study of all consecutive patients eventually diagnosed with IPF in multidisciplinary discussion who underwent SLB over 10 years in a specialized center. The primary end point was the variation in forced vital capacity (FVC) before and after the SLB. The secondary end points were the variations in forced expiratory volume in one second (FEV1), total lung capacity (TLC), carbon monoxide diffusion capacity (DLCO), and morbidity and mortality associated with the SLB.

RESULTS

In 118 patients who underwent SLB and were diagnosed with IPF, a relative decrease in FVC of 4.8% (p < 0.001) was found between measurements performed before and after the procedure. The mean FVC decrease was 156 ± 386 mL in an average period of 185 days, representing an annualized decline of 363 ± 764 mL/year. A significant decrease was also observed after SLB in FEV1, TLC, and DLCO. Complications within 30 days of SLB occurred in 14.4% of patients. Two patients (1.7%) died within 30 days, where one of them had poor lung function. Survival at 1 year was significantly poorer in patients with FVC <50% at baseline.

CONCLUSION

In this uncontrolled study in patients ultimately diagnosed with IPF, SLB was followed by a significant decline in FVC, which appears to be numerically greater than the average decline in the absence of treatment in the literature. Summary at a Glance: This study evaluated the change in lung function in 118 consecutive patients diagnosed with idiopathic pulmonary fibrosis by surgical lung biopsy. Forced vital capacity decreased by 156 ± 386 mL in a mean of 185 days between the last measurement before and first measurement after biopsy, representing an annualized decline of 363 ± 764 mL/year.

Health-related quality of life of patients with idiopathic pulmonary fibrosis: a systematic review and meta-analysis

Idiopathic pulmonary fibrosis (IPF) is one of the most common forms of interstitial lung disease presenting in persons 50 years and older. Through a comprehensive review of available studies, we aimed to assess health-related quality of life (HRQoL) of people living with IPF and the instruments used in this assessment.Searches were conducted up to May, 2020. Quality appraisal and data extraction were performed using pre-designed forms. Narrative synthesis approach was used to report results of the systematic review and a random effects model was used for the meta-analysis. A leave-one-out sensitivity analysis was performed, and a trim and fill method was used to assess publication bias.The review included 134 studies. The most used instruments to measure HRQoL were St George's Respiratory Questionnaire (SGRQ), Short Form 36 (SF36) and EuroQoL (EQ5D). Standardised mean scores (95% confidence interval) for these instruments were as follows: SGRQ total score: 44.72 (42.21-47.22); SF36 physical component score (PCS): 37.00 (34.74-39.26) SF36 mental component score (MCS): 50.18 (48.41-51.95); King's Brief Interstitial Lung Disease questionnaire total score: 58.38 (55.26-61.51); and EQ5D utility: 0.73 (0.68-0.79). Analysis of standardised means for both SGRQ and SF36 demonstrated worse scores in physical health domains as compared to mental health domains.This systematic review confirms that IPF negatively affected HRQoL, mostly impacting the physical health domains. This study also demonstrated that a diverse number of instruments are used to evaluate HRQoL. In view of this diversity, a standardised approach to measurement of HRQoL for IPF is important to ensure that comparisons made are reliable.

Artificial intelligence identifies inflammation and confirms fibroblast foci as prognostic tissue biomarkers in idiopathic pulmonary fibrosis

A large number of fibroblast foci (FF) predict mortality in idiopathic pulmonary fibrosis (IPF). Other prognostic histological markers have not been identified. Artificial intelligence (AI) offers a possibility to quantitate possible prognostic histological features in IPF. We aimed to test the use of AI in IPF lung tissue samples by quantitating FF, interstitial mononuclear inflammation, and intra-alveolar macrophages with a deep convolutional neural network (CNN). Lung tissue samples of 71 patients with IPF from the FinnishIPF registry were analyzed by an AI model developed in the Aiforia® platform. The model was trained to detect tissue, air spaces, FF, interstitial mononuclear inflammation, and intra-alveolar macrophages with 20 samples. For survival analysis, cut-point values for high and low values of histological parameters were determined with maximally selected rank statistics. Survival was analyzed using the Kaplan-Meier method. A large area of FF predicted poor prognosis in IPF (p = 0.01). High numbers of interstitial mononuclear inflammatory cells and intra-alveolar macrophages were associated with prolonged survival (p = 0.01 and p = 0.01, respectively). Of lung function values, low diffusing capacity for carbon monoxide was connected to a high density of FF (p = 0.03) and a high forced vital capacity of predicted was associated with a high intra-alveolar macrophage density (p = 0.03). The deep CNN detected histological features that are difficult to quantitate manually. Interstitial mononuclear inflammation and intra-alveolar macrophages were novel prognostic histological biomarkers in IPF. Evaluating histological features with AI provides novel information on the prognostic estimation of IPF.

How the Pathological Microenvironment Affects the Behavior of Mesenchymal Stem Cells in the Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic disease characterized by fibroblasts activation, ECM accumulation, and diffused alveolar inflammation. The role of inflammation in IPF is still controversial and its involvement may follow nontraditional mechanisms. It is seen that a pathological microenvironment may affect cells, in particular mesenchymal stem cells (MSCs) that may be able to sustain the inflamed microenvironment and influence the surrounding cells. Here MSCs have been isolated from fibrotic (IPF-MSCs) and control (C-MSCs) lung tissue; first cells were characterized and compared by the expression of molecules related to ECM, inflammation, and other interdependent pathways such as hypoxia and oxidative stress. Subsequently, MSCs were co-cultured between them and with NHLF to test the effects of the cellular crosstalk. Results showed that pathological microenvironment modified the features of MSCs: IPF-MSCs, compared to C-MSCs, express higher level of molecules related to ECM, inflammation, oxidative stress, and hypoxia; notably, when co-cultured with C-MSCs and NHLF, IPF-MSCs are able to induce a pathological phenotype on the surrounding cell types. In conclusion, in IPF the pathological microenvironment affects MSCs that in turn can modulate the behavior of other cell types favoring the progression of IPF.

Pharmacological management of Idiopathic Pulmonary Fibrosis: current and emerging options

INTRODUCTION

Idiopathic Pulmonary Fibrosis is a chronic, progressive lung disease characterized by worsening lung scarring and the radiological/histological pattern of usual interstitial pneumonia. Substantial progress has been made in the clinical management of IPF in the last decade. The two novel antifibrotics, Nintedanib and Pirfenidone have changed the landscape of IPF, by hindering disease progression; however, the drugs have significant discontinuation rates, due to adverse events and do not offer a definitive cure, as such IPF remains a deleterious disease with poor survival.

AREAS COVERED

In this review, the authors focus on the current and emerging pharmacological options in the treatment of IPF. They include a summary of the current approach including treatment of comorbidities and then discuss promising drugs in the drug pipeline.

EXPERT OPINION

IPF remains a disease with detrimental outcomes. The plethora of emerging pharmacological treatments brings hope for the future. The current pharmacological 'one fits all' approach has been proven effective in slowing disease progression. The future lies in an oncological approach with combination of therapies. We expect to see a change in clinical trial endpoints and a more inclusive approach for the diagnosis of IPF.

ABBREVIATION LIST

AE: Acute ExacerbationA-SMA: a smooth muscle actinATX: AutotaxinCOPD: Combined Obstructive Pulmonary DiseaseCPFE: Combined Pulmonary Fibrosis and EmphysemaGER: Gastro-esophageal refluxFVC: forced vital capacityECMO: extracorporeal membrane oxygenationILD: Interstitial Lung DiseaseIPF: Idiopathic Pulmonary FibrosisNAC: N-acetylcysteineLPA: Lysophosphatidic acidPH: Pulmonary RehabilitationPR: Pulmonary rehabilitationRCTs: randomized placebo-controlled trialsUIP: usual interstitial pneumonia.

A disease progression model of longitudinal lung function decline in idiopathic pulmonary fibrosis patients

Pirfenidone and nintedanib are the first two FDA-approved therapies for treatment of idiopathic pulmonary fibrosis (IPF). The clinical programs for pirfenidone and nintedanib included 1132 patients in the placebo arms and 1691 patients in the treatment arms across 6 trials. We developed a disease progression model to characterize the observed variability in lung function decline, measured as percent predicted forced vital capacity (%p-FVC), and its decrease in decline after treatment. The non-linear longitudinal change in %p-FVC was best described by a Weibull function. The median decreased decline in %p-FVC after treatment was estimated to be 1.50% (95% CI [1.12, 1.79]) and 1.96% (95% CI [1.47, 2.36]) at week 26 and week 52, respectively. Smoking status, weight, %p-FVC, %p-DLco and oxygen use at baseline were identified as significant covariates affecting decline in %p-FVC. The decreased decline in %p-FVC were observed among all subgroups of interest, of which the effects were larger at 1 year compared to 6 months. Based on the disease progression model smoking status and oxygen use at baseline may affect the treatment effect size. At week 52, the decreased decline in %p-FVC for current smokers and patients with oxygen use at baseline were 1.56 (90% CI [1.02, 1.99]) and 2.32 (90% CI [1.74, 2.86]), respectively. These prognostic factors may be used to enrich studies with patients who are more likely to respond to treatment, by demonstrating a lesser decline in lung function, and therefore provide the potential to allow for IPF studies with smaller study populations or shorter durations.

Pathology of Idiopathic Pulmonary Fibrosis Assessed by a Combination of Microcomputed Tomography, Histology, and Immunohistochemistry

Idiopathic pulmonary fibrosis (IPF) is a fibrotic disease with the histology of usual interstitial pneumonia (UIP). Although the pathologist's visual inspection is central in histologic assessments, three-dimensional microcomputed tomography (microCT) assessment may complement the pathologist's scoring. We examined associations between the histopathologic features of UIP and IPF in explanted lungs and quantitative microCT measurements, including alveolar surface density, total lung volume taken up by tissue (%), and terminal bronchiolar number. Sixty frozen samples from 10 air-inflated explanted lungs with severe IPF and 36 samples from 6 donor control lungs were scanned with microCT and processed for histologic analysis. An experienced pathologist scored three major UIP criteria (patchy fibrosis, honeycomb, and fibroblastic foci), five additional pathologic changes, and immunohistochemical staining for CD68-, CD4-, CD8-, and CD79a-positive cells, graded on a 0 to 3+ scale. The alveolar surface density and terminal bronchiolar number decreased and the tissue percentage increased in lungs with IPF compared with controls. In lungs with IPF, lower alveolar surface density and higher tissue percentage were correlated with greater scores of patchy fibrosis, fibroblastic foci, honeycomb, CD79a-positive cells, and lymphoid follicles. A decreased number of terminal bronchioles was correlated with honeycomb score but not with the other scores. The three-dimensional microCT measurements reflect the pathological UIP and IPF criteria and suggest that the reduction in the terminal bronchioles may be associated with honeycomb cyst formation.

Nintedanib can be used safely and effectively for idiopathic pulmonary fibrosis with predicted forced vital capacity ≤ 50%: A multi-center retrospective analysis

BACKGROUND

Nintedanib is a multi-kinase inhibitor approved for idiopathic pulmonary fibrosis (IPF); however, its efficacy and safety for patients with IPF and restricted pulmonary function remain unclear. Therefore, the objective of this study was to determine the efficacy and safety of nintedanib for patients with IPF and forced vital capacity (FVC) ≤ 50%.

METHODS

This was a multi-center retrospective study performed by the Okayama Respiratory Disease Study Group. Patients were allocated into FVC ≤ 50% and FVC > 50% groups based on their predicted FVC. The primary endpoints were FVC changes from baseline after 6 and 12 months.

RESULTS

45 patients were eligible for the study. 18 patients had FVC ≤ 50%, and 27 patients had FVC > 50%. Overall, 31 and 19 patients underwent pulmonary function tests at 6 and 12 months after initiating nintedanib, respectively. FVC changes from baseline at 6 and 12 months after initiating nintedanib were comparable between the two groups. Adverse events were seen in all patients, and the rates of patients who discontinued nintedanib were also comparable (38.9% vs. 37.0%, p = 1.000). Multiple regression analysis showed that age and forced expiratory volume in 1 second (FEV1)/FVC were negatively correlated with changes in FVC at 6 months after initiating nintedanib.

CONCLUSIONS

Our data suggest that nintedanib can be a useful agent for IPF patients, including those with a low FVC, and that age and FEV1/FVC are predictive markers for changes in FVC following nintedanib treatment.

The prognostic value of cardiopulmonary exercise testing in interstitial lung disease: a systematic review

The heterogeneity of interstitial lung disease (ILD) results in prognostic uncertainty concerning end-of-life discussions and optimal timing for transplantation. Effective prognostic markers and prediction models are needed. Cardiopulmonary exercise testing (CPET) provides a comprehensive assessment of the physiological changes in the respiratory, cardiovascular and musculoskeletal systems in a controlled laboratory environment. It has shown promise as a prognostic factor for other chronic respiratory conditions. We sought to evaluate the prognostic value of CPET in predicting outcomes in longitudinal studies of ILD.

MEDLINE, Embase and the Cochrane Database of Systematic Reviews were used to identify studies reporting the prognostic value of CPET in predicting outcomes in longitudinal studies of ILD. Study quality was assessed using the Quality in Prognosis Study risk of bias tool.

Thirteen studies were included that reported the prognostic value of CPET in ILD. All studies reported at least one CPET parameter predicting clinical outcomes in ILD, with survival being the principal outcome assessed. Maximum oxygen consumption, reduced ventilatory efficiency and exercise-induced hypoxaemia were all reported to have prognostic value in ILD. Issues with study design (primarily due to inherent problems of retrospective studies, patient selection and presentation of numerous CPET parameters), insufficient adjustment for important confounders and inadequate statistical analyses limit the strength of the conclusions that can be drawn at this stage.

There is insufficient evidence to confirm the value of CPET in facilitating “real-world” clinical decisions in ILD. Additional prospective studies are required to validate the putative prognostic associations reported in previous studies in carefully phenotyped patient populations.

There is presently insufficient evidence to confirm the value of CPET in facilitating “real-world” clinical decisions in ILD. Additional prospective studies are required to validate the putative prognostic associations reported in previous studies.https://bit.ly/3dfp5kq

A modified GAP model for East-Asian populations with idiopathic pulmonary fibrosis

BACKGROUND

The easy-to-calculate gender, age, and lung physiology (GAP) model shows good predictive and discriminative performance in the prognosis of idiopathic pulmonary fibrosis (IPF). However, the GAP model was not effective in predicting the prognosis accurately in previous Japanese and Korean IPF cohort studies. Therefore, we developed a modified GAP model for the East-Asian populations by weighing the GAP variables. The validity of the modified GAP model was subsequently evaluated in East-Asian IPF patients.

METHODS

The derivation cohort comprised 326 patients with IPF. Weights of the variables were adjusted on the basis of coefficients derived from Cox regression models. The total points were distributed to the three stages of the disease so that the number of patients included in each stage was appropriate. The validity of the modified model was analyzed in another Japanese cohort of 117 patients with IPF and a nationwide cohort of Korean patients with IPF.

RESULTS

Predicted survival rates differed significantly in the derivation cohort using the modified GAP model for each stage of IPF (log-rank test: stage I vs. stage II, p < 0.001; stage II vs. stage III, p < 0.001). Model performance improved according to Harrell's C-index (at three years: 0.696 in the original GAP model to 0.738 in the modified model). The performance of the modified model was validated in the Japanese validation and Korean national cohorts.

CONCLUSIONS

Our modification of the original GAP model showed improved performance in East-Asian IPF patient populations.

Patients With Fibrotic Interstitial Lung Disease Receive Supportive and Palliative Care Just Prior to Death

Background:

Fibrotic interstitial lung diseases (f-ILDs) are often progressive and incurable. As patients experience significant symptoms and have a poor prognosis, early palliative care referral is recommended.

Objective:

To examine the care delivered to patients with f-ILD during the terminal hospital admission and the past 2 years of life.

Methods:

A retrospective audit was performed for consecutive patients who died from f-ILD at 2 Australian teaching hospitals between January 1, 2012, and December 31, 2016.

Results:

Of 67 patients, 44 (66%) had idiopathic pulmonary fibrosis. Median age was 78 years. Median respiratory function: forced expiratory volume in 1 second 69.0% predicted (interquartile range [IQR]: 58.0%-77.0%), forced vital capacity 64.0% predicted (IQR = 46.8%-74.3%), and diffusing capacity of carbon monoxide 36.0% predicted (IQR = 31.0%-44.0%). In the 2 years prior to the terminal admission, 38 (57%) patients reported severe breathlessness and 17 (25%) used opioids for symptom relief. Twenty-four (36%) patients received specialist palliative care (SPC) and 11 (16%) completed advance care planning. During the terminal admission, 10 (15%) patients were admitted directly under SPC. A further 33 (49%) patients were referred to SPC, on average 1 day prior to death. Sixty-three (94%) patients received opioids and 49 (73%) received benzodiazepines for symptom management. Median starting and final opioid doses were 10 and 23 mg oral morphine equivalent/24 hours, respectively. Opioids were commenced on average 2 (IQR 1-3) days prior to death.

Conclusions:

Although most patients were identified as actively dying in the final admission, referral to SPC and use of palliative medications occurred late. Additionally, few patients accessed symptom palliation earlier in their illness.

Cardiopulmonary Exercise Testing in Patients With Interstitial Lung Disease

Interstitial lung disease (ILD) is a heterogeneous group of conditions characterized by fibrosis and/or inflammation of the lung parenchyma. The pathogenesis of ILD consistently results in exertional dyspnea and exercise intolerance. Cardiopulmonary exercise testing (CPET) provides important information concerning the pathophysiology of ILD that can help inform patient management. Despite the purported benefits of CPET, its clinical utility in ILD is not well defined; however, there is a growing body of evidence that provides insight into the potential value of CPET in ILD. Characteristic responses to CPET in patients with ILD include exercise-induced arterial hypoxemia, an exaggerated ventilatory response, a rapid and shallow breathing pattern, critically low inspiratory reserve volume, and elevated sensations of dyspnea and leg discomfort. CPET is used in ILD to determine cause(s) of symptoms such as exertional dyspnea, evaluate functional capacity, inform exercise prescription, and determine the effects of pharmacological and non-pharmacological interventions on exercise capacity and exertional symptoms. However, preliminary evidence suggests that CPET in ILD may also provide valuable prognostic information and can be used to ascertain the degree of exercise-induced pulmonary hypertension. Despite these recent advances, additional research is required to confirm the utility of CPET in patients with ILD. This brief review outlines the clinical utility of CPET in patients with ILD. Typical patterns of response are described and practical issues concerning CPET interpretation in ILD are addressed. Additionally, important unanswered questions relating to the clinical utility of CPET in the assessment, prognostication, and management of patients with ILD are identified.

A score without diffusion capacity of the lung for carbon monoxide for estimating survival in idiopathic pulmonary fibrosis

Prediction models for survival at baseline evaluation have been proposed in idiopathic pulmonary fibrosis (IPF) but include diffusion capacity of the lung for carbon monoxide, a test not available in many places. The aim of the present study was to develop a simple new mortality risk scoring system for patients with IPF at initial evaluation without diffusion capacity of the lung for carbon monoxide measurement.A total of 173 patients, 72% males, mean age 70 years, 64% smokers/ex-smokers, were included in a retrospective study. The diagnosis was made by surgical lung biopsy in 40 (23%); in the remaining patients, a usual interstitial pneumonia pattern was present in high-resolution computed tomography. Patients with forced expiratory volume in 1 second/forced vital capacity ratio (FEV1/FVC) <0.70 were excluded. Dyspnea was evaluated by magnitude of task on the Mahler scale (Chest 1984). Peripheral oxygen saturation was measured by oximetry at rest and at the end of a 4 minutes step test or a 6-minute walk test.At the end of the follow-up period, 154 (89%) of the patients had died. Based on the univariate Cox proportional-hazards model, survival (P ≤ .10) was related directly to the dyspnea score, presence of cough, lower values of FVC% and FEV1%, lower rest and oxygen desaturation during exercise, and greater FEV1/FVC. By Cox multivariate analysis, the results remained correlated to the survival dyspnea score, FVC%, and exercise peripheral oxygen saturation. A score, using these variables, was developed and was able to discriminate among 3 groups, with high, low, and intermediate survival curves.A prognostic score, taking into account dyspnea, FVC%, and oxygen desaturation during exercise, can estimate survival in IPF.

Investigation burden for patients with fibrotic interstitial lung disease at the end of life

Fibrotic interstitial lung disease (f-ILD) has a guarded prognosis, and the goal of therapy in advanced-stage disease should be symptom-based. Despite this, patients may still undergo burdensome investigation at the end of life. A retrospective audit was performed on 67 patients who died from f-ILD at the Royal Melbourne and Austin Hospitals between 2012 and 2016. Increased investigation burden was associated with lack of outpatient palliative care referral and documented advance care plan, and admission to a high-dependency unit. Eighteen per cent of patients underwent ongoing investigations after the institution of comfort care. These findings highlight the unmet end-of-life care needs of people with f-ILD.