Unravelling the health and economic burden of interstitial lung diseases in adults in Australia

BACKGROUND

Interstitial lung diseases (ILD) are a heterogenous group of over 200 disorders affecting the pulmonary interstitium. Although there have been advances in knowledge on ILDs in Australia, the characterisation of the health and economic burden of disease remained largely undetermined until recently.

OBJECTIVE

The main objective of this review is to provide a synopsis of health and economic burden of ILDs in Australia, based on recently completed research.

DISCUSSION

Recent research has demonstrated that idiopathic pulmonary fibrosis (IPF) is the most frequent ILD in Australia. Incidence and prevalence of IPF have demonstrated an increasing trend over the past decades. Mortality has also increased over the past decades, but has shown a slight decreasing trend recently, since the introduction of antifibrotic medication. Health-related quality of life is poor in patients with IPF, and care is estimated to cost approximately AU$299 million per year in Australia. Early diagnosis and referral to tertiary care is crucial for favourable outcomes, and general practitioners are considerably important to this as the first interface to identify patients at risk and detect early symptoms of ILDs.

Zinpentraxin Alfa for Idiopathic Pulmonary Fibrosis: The Randomized Phase III STARSCAPE Trial

Rationale: A phase II trial reported clinical benefit over 28 weeks in patients with idiopathic pulmonary fibrosis (IPF) who received zinpentraxin alfa. Objectives: To investigate the efficacy and safety of zinpentraxin alfa in patients with IPF in a phase III trial. Methods: This 52-week phase III, double-blind, placebo-controlled, pivotal trial was conducted at 275 sites in 29 countries. Patients with IPF were randomized 1:1 to intravenous placebo or zinpentraxin alfa 10 mg/kg every 4 weeks. The primary endpoint was absolute change from baseline to Week 52 in FVC. Secondary endpoints included absolute change from baseline to Week 52 in percent predicted FVC and 6-minute walk distance. Safety was monitored via adverse events. Post hoc analysis of the phase II and phase III data explored changes in FVC and their impact on the efficacy results. Measurements and Main Results: Of 664 randomized patients, 333 were assigned to placebo and 331 to zinpentraxin alfa. Four of the 664 randomized patients were never administered study drug. The trial was terminated early after a prespecified futility analysis that demonstrated no treatment benefit of zinpentraxin alfa over placebo. In the final analysis, absolute change from baseline to Week 52 in FVC was similar between placebo and zinpentraxin alfa (-214.89 ml and -235.72 ml; P = 0.5420); there were no apparent treatment effects on secondary endpoints. Overall, 72.3% and 74.6% of patients receiving placebo and zinpentraxin alfa, respectively, experienced one or more adverse events. Post hoc analysis revealed that extreme FVC decline in two placebo-treated patients resulted in the clinical benefit of zinpentraxin alfa reported by phase II. Conclusions: Zinpentraxin alfa treatment did not benefit patients with IPF over placebo. Learnings from this program may help improve decision making around trials in IPF. Clinical trial registered with www.clinicaltrials.gov (NCT04552899).

Reply to: Optimal clinical practice in IPF and PPF: Integrating scientific ethos and clinical reasoning

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Genetics and Genomics of Pulmonary Fibrosis: Charting the Molecular Landscape and Shaping Precision Medicine

Recent genetic and genomic advancements have elucidated the complex etiology of idiopathic pulmonary fibrosis (IPF) and other progressive fibrotic interstitial lung diseases (ILDs), emphasizing the contribution of heritable factors. This state-of-the-art review synthesizes evidence on significant genetic contributors to pulmonary fibrosis (PF), including rare genetic variants and common single nucleotide polymorphisms (SNPs). The MUC5B promoter variant is unusual, a common SNP that markedly elevates the risk of early and established PF. We address the utility of genetic variation in enhancing understanding of disease pathogenesis, clinical phenotypes, improving disease definitions, and informing prognosis and treatment response. Critical research gaps are highlighted, particularly the underrepresentation of non-European ancestries in PF genetic studies and the exploration of PF phenotypes beyond usual interstitial pneumonia (UIP)/IPF. We discuss the role of telomere length, often critically short in PF, and its link to progression and mortality, underscoring the genetic complexity involving telomere biology genes (TERT, TERC) and others like SFTPC and MUC5B. Additionally, we address the potential of gene-by-environment interactions to modulate disease manifestation, advocating for precision medicine in PF. Insights from gene expression profiling studies and multi-omic analyses highlight the promise for understanding disease pathogenesis and offer new approaches to clinical care, therapeutic drug development, and biomarker discovery. Finally, we discuss the ethical, legal, and social implications of genomic research and therapies in PF, stressing the need for sound practices and informed clinical genetic discussions. Looking forward, we advocate for comprehensive genetic testing panels and polygenic risk scores to improve the management of PF and related ILDs across diverse populations.

Mortality surrogates in combined pulmonary fibrosis and emphysema

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Disease Behaviour Classification: A pragmatic model for predicting outcomes in Interstitial Lung Disease

BACKGROUND AND OBJECTIVE

The interstitial lung diseases (ILD) are a heterogenous group of disorders with similar clinical presentation, but widely varying prognoses. The use of a pragmatic disease behaviour classification (DBC), first proposed in international guidelines in 2013, categorises diseases into five behavioural classes based on their predicted clinical course. This study aimed to determine the prognostic utility of the DBC in an ILD cohort.

METHODS

Consecutive patients presented at the weekly multidisciplinary meeting (MDM) of a specialist ILD centre were included. MDM consensus was obtained for diagnosis and DBC category (1-5). Baseline and serial clinical and physiological data were collected over the study period (median 3.9 years, range 0-5.4 years). The relationship between DBC and prognostic outcomes was explored.

RESULTS

137 ILD patients, [64 (47%) female] were included with mean age 67.0 ± 1.1 years, baseline FVC% 72.7 ± 1.7, and baseline DLco% 57.8 ± 1.6%. Patients were stratified into DBC by consensus at MDM: DBC1 n = 0 (0%), DBC2 n = 16 (12%), DBC3 n = 10 (7.3%), DBC4 n = 55 (40%), and DBC5 n = 56 (41%). On univariable Cox regression, increasing DBC class was associated with poorer progression-free survival (HR 1.6, 95% CI 1.2-2.0, p < 0.001). On multivariable Cox regression, DBC remained predictive of PFS when combined with age and gender (HR 1.4, 95% CI 1.1-1.9, p = 0.011), baseline FVC% (HR 1.5, 95% CI 1.1-1.8, p = 0.003) and ILD diagnosis (HR 1.6, 95% CI 1.2-2.2, p < 0.0001).

CONCLUSION

DBC as determined at ILD multidisciplinary meeting may be a useful prognostic tool for the management of ILD patients.

Multiple serum biomarkers associate with mortality and interstitial lung disease progression in systemic sclerosis

OBJECTIVES

To investigate the prognostic utility of 28 serum biomarkers in systemic sclerosis (SSc), SSc-associated interstitial lung disease (SSc-ILD) and clinically relevant disease subgroups.

METHODS

Participants with sera, high-resolution computed tomography, and lung function within 12 months of baseline were identified from the Australian Scleroderma Cohort Study. Baseline was the time of serum collection. 27 of the prespecified 28 serum biomarkers were analysed and biomarker associations with mortality and ILD progression were investigated in univariable and multivariable analyses, including within disease subgroups and combined with established risk factors for poorer prognosis in SSc.

RESULTS

407 participants were identified, 252 (61.9%) with SSc-ILD. The median follow up after biomarker measurement was 6.31 (3.11-9.22) years. 16 biomarkers were associated with increased mortality. High levels of VCAM-1 were most strongly associated with mortality (HR 3.55; 95%CI 2.37-5.33; p< 0.001). Five additional biomarkers had a HR > 2: SP-D (2.28, 1.57-3.31; p< 0.001), E-selectin (2.19; 1.53-3.14; p< 0.001), IL-6 (2.15 1.50-3.09; p< 0.001), MMP3 (1.42-2.95; p< 0.001) and ET-1 (2.03, 1.40-2.92; p< 0.001). 11 biomarkers were independently associated with mortality following adjustment for sex, age and baseline forced vital capacity (FVC%predicted). Three biomarkers were associated with ILD progression at one year follow up: CXCL4 (OR 2.67, 1.46-4.88; p= 0.001), MMP-1 (2.56, 1.43-4.59; p= 0.002) and ET-1 (2.18, 1.24-3.83; p= 0.007).

CONCLUSION

Multiple biomarkers, especially VCAM-1, E-Selectin, SP-D and CXCL4, provide prognostic utility beyond that of established risk factors for patients with SSc.

Agreement between local and central anti-synthetase antibodies detection: results from the Classification Criteria of Anti-Synthetase Syndrome project biobank

OBJECTIVES

The CLASS (Classification Criteria of Anti-Synthetase Syndrome) project is a large international multicentre study that aims to create the first data-driven anti-synthetase syndrome (ASSD) classification criteria. Identifying anti-aminoacyl tRNA synthetase antibodies (anti-ARS) is crucial for diagnosis, and several commercial immunoassays are now available for this purpose. However, using these assays risks yielding false-positive or false-negative results, potentially leading to misdiagnosis. The established reference standard for detecting anti-ARS is immunoprecipitation (IP), typically employed in research rather than routine autoantibody testing. We gathered samples from participating centers and results from local anti-ARS testing. As an "ad-interim" study within the CLASS project, we aimed to assess how local immunoassays perform in real-world settings compared to our central definition of anti-ARS positivity.

METHODS

We collected 787 serum samples from participating centres for the CLASS project and their local anti-ARS test results. These samples underwent initial central testing using RNA-IP. Following this, the specificity of ARS was reconfirmed centrally through ELISA, line-blot assay (LIA), and, in cases of conflicting results, protein-IP. The sensitivity, specificity, positive likelihood ratio and positive and negative predictive values were evaluated. We also calculated the inter-rater agreement between central and local results using a weighted κ co-efficient.

RESULTS

Our analysis demonstrates that local, real-world detection of anti-Jo1 is reliable with high sensitivity and specificity with a very good level of agreement with our central definition of anti-Jo1 antibody positivity. However, the agreement between local immunoassay and central determination of anti-non-Jo1 antibodies varied, especially among results obtained using local LIA, ELISA and "other" methods.

CONCLUSIONS

Our study evaluates the performance of real-world identification of anti-synthetase antibodies in a large cohort of multi-national patients with ASSD and controls. Our analysis reinforces the reliability of real-world anti-Jo1 detection methods. In contrast, challenges persist for anti-non-Jo1 identification, particularly anti-PL7 and rarer antibodies such as anti-OJ/KS. Clinicians should exercise caution when interpreting anti-synthetase antibodies, especially when commercial immunoassays test positive for non-anti-Jo1 antibodies.

Treatment of idiopathic pulmonary fibrosis and progressive pulmonary fibrosis: A position statement from the Thoracic Society of Australia and New Zealand 2023 revision

Idiopathic pulmonary fibrosis (IPF) is a progressive disease leading to significant morbidity and mortality. In 2017 the Thoracic Society of Australia and New Zealand (TSANZ) and Lung Foundation Australia (LFA) published a position statement on the treatment of IPF. Since that time, subsidized anti-fibrotic therapy in the form of pirfenidone and nintedanib is now available in both Australia and New Zealand. More recently, evidence has been published in support of nintedanib for non-IPF progressive pulmonary fibrosis (PPF). Additionally, there have been numerous publications relating to the non-pharmacologic management of IPF and PPF. This 2023 update to the position statement for treatment of IPF summarizes developments since 2017 and reaffirms the importance of a multi-faceted approach to the management of IPF and progressive pulmonary fibrosis.

The impact of air pollution on interstitial lung disease: a systematic review and meta-analysis

Introduction

There is a growing body of evidence suggesting a causal relationship between interstitial lung disease (ILD) and air pollution, both for the development of the disease, and driving disease progression. We aim to provide a comprehensive literature review of the association between air pollution, and ILD, including idiopathic pulmonary fibrosis (IPF).

Methods

We systematically searched from six online database. Two independent authors (DL and CF) selected studies and critically appraised the risk of bias using the Newcastle-Ottawa Scale (NOS). Findings are presented through a narrative synthesis and meta-analysis. Meta-analyses were performed exclusively when there was a minimum of three studies examining identical pollutant-health outcome pairs, all evaluating equivalent increments in pollutant concentration, using a random effects model.

Results

24 observational studies conducted in 13 countries or regions were identified. Pollutants under investigation encompassed ozone (O3), nitrogen dioxide (NO2), Particulate matter with diameters of 10 micrometers or less (PM10) and 2.5 micrometers or less (PM2.5), sulfur dioxide (SO2), carbon monoxide (CO), nitric oxide (NO) and nitrogen oxides (NOx). We conducted meta-analyses to assess the estimated Risk Ratios (RRs) for acute exacerbations (AE)-IPF in relation to exposure to every 10 μg/m3 increment in air pollutant concentrations, including O3, NO2, PM10, and PM2.5. The meta-analysis revealed a significant association between the increased risk of AE-IPF in PM2.5, yielding RR 1.94 (95% CI 1.30-2.90; p = 0.001). Findings across all the included studies suggest that increased exposure to air pollutants may be linked to a range of health issues in individuals with ILDs.

Conclusion

A scarcity of available studies on the air pollutants and ILD relationship underscores the imperative for further comprehensive research in this domain. The available data suggest that reducing levels of PM2.5 in the atmosphere could potentially reduce AE frequency and severity in ILD patients.

Drug-induced interstitial lung disease: a narrative review of a clinical conundrum

INTRODUCTION

Drug-induced interstitial lung disease (DI-ILD) is increasing in incidence, due to the use of many new drugs across a broad range of cancers and chronic inflammatory diseases. The presentation and onset of DI-ILD are variable even for the same drug across different individuals. Clinical suspicion is essential for identifying these conditions, with timely drug cessation an important determinant of outcomes.

AREAS COVERED

This review provides a comprehensive and up-to-date summary of epidemiology, risk factors, pathogenesis, diagnosis, treatment, and prognosis of DI-ILD. Relevant research articles from PubMed and Medline searches up to September 2023 were screened and summarized. Specific drugs including immune checkpoint inhibitors, CAR-T cell therapy, methotrexate, and amiodarone are discussed in detail. The potential role of pharmacogenomic profiling for lung toxicity risk is considered.

EXPERT OPINION

DI-ILD is likely to be an increasingly important contributor to respiratory disability in the community. These conditions can negatively impact quality of life and patient longevity, due to associated respiratory compromise as well as cessation of evidence-based therapy for the underlying disease. This clinical conundrum is relevant to all areas of medicine, necessitating increased understanding and greater vigilance for drug-related lung toxicity.

Occupational interstitial lung diseases

Millions of workers are exposed to substances known to cause occupational interstitial lung diseases (ILDs), particularly in developing countries. However, the burden of the disease is likely to be underestimated due to under-recognition, under-reporting or both. The diagnosis of occupational ILD requires a high level of suspicion and a thorough occupational history, as occupational and non-occupational ILDs may be clinically, functionally and radiologically indistinguishable, leading to delayed diagnosis and inappropriate management. A potential occupational aetiology should always be considered in the differential diagnosis of ILD, as removal from the workplace exposure, with or without treatment, is a key therapeutic intervention and may lead to significant improvement. In this article, we provide an overview of the 'traditional' inorganic dust-related ILDs but also address idiopathic pulmonary fibrosis and the immunologically mediated chronic beryllium disease, sarcoidosis and hypersensitivity pneumonitis, with emphasis on the importance of surveillance and prevention for reducing the burden of these conditions. To this end, health-care professionals should be specifically trained about the importance of occupational exposures as a potential cause of ILD.

Long-term exposure to low concentrations of air pollution and decline in lung function in people with idiopathic pulmonary fibrosis: Evidence from Australia

BACKGROUND AND OBJECTIVE

Little is known about the association between ambient air pollution and idiopathic pulmonary fibrosis (IPF) in areas with lower levels of exposure. We aimed to investigate the impact of air pollution on lung function and rapid progression of IPF in Australia.

METHODS

Participants were recruited from the Australian IPF Registry (n = 570). The impact of air pollution on changes in lung function was assessed using linear mixed models and Cox regression was used to investigate the association with rapid progression.

RESULTS

Median (25th-75th percentiles) annual fine particulate matter (<2.5 μm, PM2.5 ) and nitrogen dioxide (NO2 ) were 6.8 (5.7, 7.9) μg/m3 and 6.7 (4.9, 8.2) ppb, respectively. Compared to living more than 100 m from a major road, living within 100 m was associated with a 1.3% predicted/year (95% confidence interval [CI] -2.4 to -0.3) faster annual decline in diffusing capacity of the lungs for carbon monoxide (DLco). Each interquartile range (IQR) of 2.2 μg/m3 increase in PM2.5 was associated with a 0.9% predicted/year (95% CI -1.6 to -0.3) faster annual decline in DLco, while there was no association observed with NO2 . There was also no association between air pollution and rapid progression of IPF.

CONCLUSION

Living near a major road and increased PM2.5 were both associated with an increased rate of annual decline in DLco. This study adds to the evidence supporting the negative effects of air pollution on lung function decline in people with IPF living at low-level concentrations of exposure.

Pulmonary hypertension associated with lung disease: new insights into pathomechanisms, diagnosis, and management

Patients with chronic lung diseases, particularly interstitial lung disease and chronic obstructive pulmonary disease, frequently develop pulmonary hypertension, which results in clinical deterioration, worsening of oxygen uptake, and an increased mortality risk. Pulmonary hypertension can develop and progress independently from the underlying lung disease. The pulmonary vasculopathy is distinct from that of other forms of pulmonary hypertension, with vascular ablation due to loss of small pulmonary vessels being a key feature. Long-term tobacco exposure might contribute to this type of pulmonary vascular remodelling. The distinct pathomechanisms together with the underlying lung disease might explain why treatment options for this condition remain scarce. Most drugs approved for pulmonary arterial hypertension have shown no or sometimes harmful effects in pulmonary hypertension associated with lung disease. An exception is inhaled treprostinil, which improves exercise capacity in patients with interstitial lung disease and pulmonary hypertension. There is a pressing need for safe, effective treatment options and for reliable, non-invasive diagnostic tools to detect and characterise pulmonary hypertension in patients with chronic lung disease.

The economic burden of idiopathic pulmonary fibrosis in Australia: a cost of illness study

PURPOSE

Idiopathic pulmonary fibrosis (IPF) is a type of interstitial lung disease found mostly in elderly persons, characterized by a high symptom burden and frequent encounters with health services. This study aimed to quantify the economic burden of IPF in Australia with a focus on resource utilization and associated direct costs.

METHODS

Participants were recruited from the Australian IPF Registry (AIPFR) between August 2018 and December 2019. Data on resource utilization and costs were collected via cost diaries and linked administrative data. Clinical data were collected from the AIPFR. A "bottom up" costing methodology was utilized, and the costing was performed from a partial societal perspective focusing primarily on direct medical and non-medical costs. Costs were standardized to 2021 Australian dollars ($).

RESULTS

The average annual total direct costs per person with IPF was $31,655 (95% confidence interval (95% CI): $27,723-$35,757). Extrapolating costs based on prevalence estimates, the total annual costs in Australia are projected to be $299 million (95% CI: $262 million-$338 million). Costs were mainly driven by antifibrotic medication, hospital admissions and medications for comorbidities. Disease severity, comorbidities and antifibrotic medication all had varying impacts on resource utilization and costs.

CONCLUSION

This cost-of-illness study provides the first comprehensive assessment of IPF-related direct costs in Australia, identifies the key cost drivers and provides a framework for future health economic analyses. Additionally, it provided insight into the major cost drivers which include antifibrotic medication, hospital admissions and medications related to comorbidities. Our findings emphasize the importance of the appropriate management of comorbidities in the care of people with IPF as this was one of the main reasons for hospitalizations.

Idiopathic Pulmonary Fibrosis Is Associated with Common Genetic Variants and Limited Rare Variants

Rationale: Idiopathic pulmonary fibrosis (IPF) is a rare, irreversible, and progressive disease of the lungs. Common genetic variants, in addition to nongenetic 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 rare variants that are influential within genes and estimated the heritability of IPF on the basis of 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% (SE = 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 the 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.

Sex- and Race-Based Differences in the Treatment of Interstitial Lung Diseases in North America and Australasia

BACKGROUND

Biological sex, gender, and race are important considerations in patients with interstitial lung diseases (ILDs).

RESEARCH QUESTION

Does a patient's sex assigned at birth, and race, influence ILD treatment initiation?

STUDY DESIGN AND METHODS

Patients with ILD from three longitudinal prospective registries were compared in this observational study. ILD-related medications included antifibrotics and immunomodulating medications. Race was dichotomized as "White" vs "non-White." Time to treatment initiation was determined from the date of the initial ILD registry visit to the date of first medication initiation. Proportions of treated patients were compared between groups by χ2 test. Cox proportional analysis was used to determine how sex and race were associated with time to treatment initiation stratified by ILD diagnosis.

RESULTS

A total of 4,572 patients were included across all cohorts. The proportion of men who received treatment was higher than for women in the Canadian cohort (47% vs 40%; P < .001), and the proportion of White patients who received treatment was also higher compared with non-White patients (46% vs 36%; P < .001). In contrast, the proportion of treated men in the Chicago cohort was lower compared with women (56% vs 64%; P = .005), and that of White patients was lower compared with non-White patients (56% vs 69%; P < .001). No sex- or race-based differences in proportions of patients treated were found in the Australasian cohort. White race was significantly associated with earlier treatment initiation compared with non-White race across diagnoses in the Canadian cohort, whereas the opposite association was found in the Australasian cohort.

INTERPRETATION

Sex- and race-based differences exist in the initiation of ILD treatment, with variability across different cohorts in different countries. Reasons for these differences need to be further explored in future studies.

A composite serum biomarker index for the diagnosis of systemic sclerosis interstitial lung disease: a multicentre, observational, cohort study

OBJECTIVE

In patients with systemic sclerosis (SSc), we investigated composite serum biomarker panels for the diagnosis and risk-stratification of SSc-associated interstitial lung disease (SSc-ILD).

METHODS

Twenty-eight biomarkers were analysed in 640 participants: 259 with SSc-ILD and 179 SSc-controls without ILD (Australian Scleroderma Cohort Study), 172 idiopathic pulmonary fibrosis (IPF)-controls (Australian IPF Registry), and 30 healthy controls. A composite index was developed from biomarkers associated with ILD in multivariable analysis derived at empirical thresholds. Performance of the index to identify ILD, and specifically SSc-ILD, and its association with lung function, radiological extent, health-related quality of life (HRQoL) were evaluated in derivation and validation cohorts. Biomarkers to distinguish SSc-ILD from IPF-controls were identified.

RESULTS

A composite biomarker index, comprising SP-D, Ca15-3 and ICAM-1, was strongly associated with SSc-ILD diagnosis, independent of age, sex, smoking and lung function (index=3: pooled adjusted OR 12.72, 95%CI 4.59-35.21, p<0.001). The composite index strengthened the performance of individual biomarkers for SSc-ILD identification. In SSc patients, a higher index was associated with worse baseline disease severity (index=3 relative to index=0: adjusted absolute change in FVC% ^- 17.84% and DLCO% ^- 20.16%, both p<0.001).

CONCLUSION

A composite serum biomarker index, comprising SP-D, Ca15-3 and ICAM-1 may improve the identification and risk-stratification of ILD in SSc patients at baseline.

Assessment of health-related quality of life in Australian patients with idiopathic pulmonary fibrosis: a comparison of the EQ-5D-5L and the AQoL-8D

PURPOSE

Idiopathic pulmonary fibrosis (IPF) is a progressive and debilitating chronic lung disease with a high symptom burden, which has a substantial impact on health-related quality of life (HRQoL). Our study aimed to assess the suitability of the EuroQol five-dimension (EQ-5D-5L) and the Assessment of Quality of Life- eight-dimension (AQoL-8D) questionnaires in measuring HRQoL as health state utility values (HSUVs) in an Australian IPF cohort.

METHODS

Data for estimation of health state utility values (HSUVs) were collected from participants of the Australian IPF Registry (AIPFR) using self-administered surveys which included the EQ-5D-5L and the AQoL-8D. Data on lung function and disease specific HRQoL instruments were collected from the AIPFR. Performance of the two instruments was evaluated based on questionnaire practicality, agreement between the two instruments and test performance (internal and construct validity).

RESULTS

Overall completion rates for the EQ-5D-5L and AQoL-8D were 96% and 85%, respectively. Mean (median) HSUVs were 0.65 (0.70) and 0.69 (0.72) for the EQ-5D-5L and AQoL-8D, respectively. There was reasonable agreement between the two instruments based on the Bland-Altman plot mean difference (-0.04) and intraclass correlation coefficient (0.84), however there were some fundamental differences. A larger range of values was observed with the EQ-5D-5L (-0.57-1.00 vs 0.16-1.00). The EQ-5D-5L had a greater divergent sensitivity and efficacy in relation to assessing HSUVs between clinical groupings. The AQoL-8D ,however, had a higher sensitivity to measure psychosocial aspects of HRQoL in IPF.

CONCLUSION

The EQ-5D-5L demonstrated superior performance when compared to AQoL-8D in persons with IPF. This may be attributable to the high symptom burden which is physically debilitating to which the EQ-5D-5L may be more sensitive.

Mapping EQ5D utilities from forced vital capacity and diffusing capacity in fibrotic interstitial lung disease

OBJECTIVES

Fibrotic interstitial lung disease (ILD) includes a large group of conditions that lead to scarring of the lungs. The lack of available 5-level EuroQol 5D (EQ5D) data has limited the ability to conduct economic evaluations in ILD. The purpose of this study was to develop and validate a mapping algorithm that predicts EQ5D utilities from commonly collected pulmonary function measurements (forced vital capacity [FVC] and diffusing capacity of the lung for carbon monoxide [DLCO]) in fibrotic ILDs.

METHODS

EQ5D utility and pulmonary function measurements from the Canadian Registry for Pulmonary Fibrosis were included. Ordinary least squares (OLS), beta regression, two-part, and tobit models were used to map EQ5D utilities from FVC or DLCO. Model performance was assessed by comparing the predicted and observed utilities. Subgroup analyses were also conducted to test how well models performed across different patient characteristics. The models were then externally validated in the Australian Idiopathic Pulmonary Fibrosis Registry.

RESULTS

The OLS model performed as well as other more complex models (root mean squared error: 0.17 for FVC and 0.16 for DLCO). As with the other models, the OLS algorithm performed well across the different subgroups (except for EQ5D utilities < 0.5) and in the external validation cohort.

CONCLUSION

We developed a mapping algorithm that predicts EQ5D utilities from FVC and DLCO, with the intent that this algorithm can be applied to clinical trial populations and real-world cohorts that have not prioritized collection of health-related utilities. The mapping algorithm can be used in future economic evaluations of potential ILD therapies.

Machine learning in radiology: the new frontier in interstitial lung diseases

Challenges for the effective management of interstitial lung diseases (ILDs) include difficulties with the early detection of disease, accurate prognostication with baseline data, and accurate and precise response to therapy. The purpose of this Review is to describe the clinical and research gaps in the diagnosis and prognosis of ILD, and how machine learning can be applied to image biomarker research to close these gaps. Machine-learning algorithms can identify ILD in at-risk populations, predict the extent of lung fibrosis, correlate radiological abnormalities with lung function decline, and be used as endpoints in treatment trials, exemplifying how this technology can be used in care for people with ILD. Advances in image processing and analysis provide further opportunities to use machine learning that incorporates deep-learning-based image analysis and radiomics. Collaboration and consistency are required to develop optimal algorithms, and candidate radiological biomarkers should be validated against appropriate predictors of disease outcomes.

Novel diagnostic techniques in interstitial lung disease

Research into novel diagnostic techniques and targeted therapeutics in interstitial lung disease (ILD) is moving the field toward increased precision and improved patient outcomes. An array of molecular techniques, machine learning approaches and other innovative methods including electronic nose technology and endobronchial optical coherence tomography are promising tools with potential to increase diagnostic accuracy. This review provides a comprehensive overview of the current evidence regarding evolving diagnostic methods in ILD and to consider their future role in routine clinical care.

The relative contribution of co-morbidities to health-related quality of life of people with idiopathic pulmonary fibrosis using the Assessment of Quality of Life-8-Dimension multi-attribute utility instrument

PURPOSE

Little is known about the impact of co-morbidities on health-related quality of life (HRQoL) for people with idiopathic pulmonary fibrosis (IPF). We aimed to investigate the relative contribution of co-morbidities to HRQoL of people with IPF.

METHODS

N = 157 participants were recruited from the Australian IPF Registry (AIPFR). Health state utilities (HSUs), and the super-dimensions of physical and psychosocial scores were measured using the Assessment of Quality of Life-8-Dimensions (AQoL-8D). The impact of co-morbidities on HRQoL was investigated using linear regression and general dominance analyses.

RESULTS

A higher number of co-morbidities was associated with lower HSUs (p trend = 0.002). Co-morbidities explained 9.1% of the variance of HSUs, 16.0% of physical super-dimensional scores, and 4.2% of psychosocial super-dimensional scores. Arthritis was associated with a significant reduction on HSUs (β =  - 0.09, 95% confidence interval [CI] - 0.16 to - 0.02), largely driven by reduced scores on the physical super-dimension (β =  - 0.13, 95% CI - 0.20 to - 0.06). Heart diseases were associated with a significant reduction on HSUs (β =  - 0.09, 95% CI - 0.16 to - 0.02), driven by reduced scores on physical (β =  - 0.09, 95% CI - 0.16 to - 0.02) and psychosocial (β = -0.10, 95% CI - 0.17 to - 0.02) super-dimensions.

CONCLUSIONS

Co-morbidities significantly impact HRQoL of people with IPF, with markedly negative impacts on their HSUs and physical health. A more holistic approach to the care of people with IPF is important as better management of these co-morbidities could lead to improved HRQoL in people with IPF.

Quantitative computed tomography predicts outcomes in idiopathic pulmonary fibrosis

BACKGROUND AND OBJECTIVE

Prediction of disease course in patients with progressive pulmonary fibrosis remains challenging. The purpose of this study was to assess the prognostic value of lung fibrosis extent quantified at computed tomography (CT) using data-driven texture analysis (DTA) in a large cohort of well-characterized patients with idiopathic pulmonary fibrosis (IPF) enrolled in a national registry.

METHODS

This retrospective analysis included participants in the Australian IPF Registry with available CT between 2007 and 2016. CT scans were analysed using the DTA method to quantify the extent of lung fibrosis. Demographics, longitudinal pulmonary function and quantitative CT metrics were compared using descriptive statistics. Linear mixed models, and Cox analyses adjusted for age, gender, BMI, smoking history and treatment with anti-fibrotics were performed to assess the relationships between baseline DTA, pulmonary function metrics and outcomes.

RESULTS

CT scans of 393 participants were analysed, 221 of which had available pulmonary function testing obtained within 90 days of CT. Linear mixed-effect modelling showed that baseline DTA score was significantly associated with annual rate of decline in forced vital capacity and diffusing capacity of carbon monoxide. In multivariable Cox proportional hazard models, greater extent of lung fibrosis was associated with poorer transplant-free survival (hazard ratio [HR] 1.20, p < 0.0001) and progression-free survival (HR 1.14, p < 0.0001).

CONCLUSION

In a multi-centre observational registry of patients with IPF, the extent of fibrotic abnormality on baseline CT quantified using DTA is associated with outcomes independent of pulmonary function.

Clinical utility of a standardized chronic hypersensitivity pneumonitis exposure questionnaire

BACKGROUND AND OBJECTIVE

Identification of an exposure is integral to the diagnosis, management, and prognostication of chronic hypersensitivity pneumonitis (CHP). Standardized questionnaires may aid in the identification of exposures, however, there currently are no evidence-based patient-validated questionnaires available. Key qualifiers (including duration and frequency) which indicate exposure relevance are also poorly defined. This study assessed the use of a standardized CHP exposure questionnaire in the identification of exposures and diagnostic confidence of CHP.

METHODS

People with a multi-disciplinary meeting (MDM) diagnosis from five Australian interstitial lung disease (ILD) expert centres who provided informed consent were included. Participants completed a previously developed standardized CHP Exposure Questionnaire. Responses were collected with the participant's MDM data, including diagnosis, diagnostic confidence, and clinician-elicited exposures.

RESULTS

One hundred thirty participants (IPF = 58, CHP = 24, CTD-ILD = 17, unclassifiable = 19, other = 12) were included. In 33% of CHP participants, a standardized questionnaire elicited an exposure where the clinician did not. 63% of these had provisional low confidence CHP; and an exposure history would have increased the diagnostic confidence in these cases. Using the standardized questionnaire, 96% of CHP participants reporting any exposure, compared with 75% of non-HP ILD participants. CHP participants were 3.5 times more likely (p = 0.004) to report their symptoms improved on avoidance, and 2.3 times more likely (p = 0.018) to report daily frequent exposure, compared with non-HP ILDs.

CONCLUSION

A standardized questionnaire which elicits exposure characteristics in addition to presence or absence of relevant exposures can increase the diagnostic confidence of CHP and reduce the proportion of antigen-indeterminate CHP.

Diagnosing interstitial lung disease by multidisciplinary discussion: A review

The multidisciplinary meeting (MDM) has been endorsed in current international consensus guidelines as the gold standard method for diagnosis of interstitial lung disease (ILD). In the absence of an accurate and reliable diagnostic test, the agreement between multidisciplinary meetings has been used as a surrogate marker for diagnostic accuracy. Although the ILD MDM has been shown to improve inter-clinician agreement on ILD diagnosis, result in a change in diagnosis in a significant proportion of patients and reduce unclassifiable diagnoses, the ideal form for an ILD MDM remains unclear, with constitution and processes of ILD MDMs varying greatly around the world. It is likely that this variation of practice contributes to the lack of agreement seen between MDMs, as well as suboptimal diagnostic accuracy. A recent Delphi study has confirmed the essential components required for the operation of an ILD MDM. The ILD MDM is a changing entity, as it incorporates new diagnostic tests and genetic markers, while also adapting in its form in response to the obstacles of the COVID-19 pandemic. The aim of this review was to evaluate the current evidence regarding ILD MDM and their role in the diagnosis of ILD, the practice of ILD MDM around the world, approaches to ILD MDM standardization and future directions to improve diagnostic accuracy in ILD.

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

Background: The presence of emphysema is relatively common in patients with fibrotic interstitial lung disease. This has been designated combined pulmonary fibrosis and emphysema (CPFE). The lack of consensus over definitions and diagnostic criteria has limited CPFE research. Goals: The objectives of this task force were to review the terminology, definition, characteristics, pathophysiology, and research priorities of CPFE and to explore whether CPFE is a syndrome. Methods: This research statement was developed by a committee including 19 pulmonologists, 5 radiologists, 3 pathologists, 2 methodologists, and 2 patient representatives. The final document was supported by a focused systematic review that identified and summarized all recent publications related to CPFE. Results: This task force identified that patients with CPFE are predominantly male, with a history of smoking, severe dyspnea, relatively preserved airflow rates and lung volumes on spirometry, severely impaired DlCO, exertional hypoxemia, frequent pulmonary hypertension, and a dismal prognosis. The committee proposes to identify CPFE as a syndrome, given the clustering of pulmonary fibrosis and emphysema, shared pathogenetic pathways, unique considerations related to disease progression, increased risk of complications (pulmonary hypertension, lung cancer, and/or mortality), and implications for clinical trial design. There are varying features of interstitial lung disease and emphysema in CPFE. The committee offers a research definition and classification criteria and proposes that studies on CPFE include a comprehensive description of radiologic and, when available, pathological patterns, including some recently described patterns such as smoking-related interstitial fibrosis. Conclusions: This statement delineates the syndrome of CPFE and highlights research priorities.

Efficacy of Pirfenidone vs. Placebo in Unclassifiable Interstitial Lung Disease, by Surgical Lung Biopsy Status: Data From a post-hoc Analysis

Approximately 12–13% of patients with interstitial lung disease (ILD) are diagnosed with unclassifiable ILD (uILD), often despite thorough evaluation. A recent Phase 2 study (NCT03099187) described a significant effect of pirfenidone vs. placebo on forced vital capacity (FVC) measured by site spirometry in patients with progressive fibrosing uILD (hereafter referred to as the pirfenidone in uILD study). Here, we present the results from a post-hoc analysis of this study to assess patient baseline characteristics and the efficacy of pirfenidone vs. placebo analyzed by surgical lung biopsy (SLB) status. Mean FVC (mL) change over 24 weeks was included as a post-hoc efficacy outcome. Of 253 randomized patients, 88 (34.8%) had a SLB and 165 (65.2%) did not. Baseline characteristics were generally similar between SLB subgroups; however, patients who had a SLB were slightly younger and had a higher 6-min walk distance than those without a SLB. Mean FVC change over 24 weeks for pirfenidone vs. placebo was −90.9 vs. −146.3 mL, respectively, in patients who had a SLB, and 8.2 vs. −85.3 mL, respectively, in patients without a SLB. Overall, the results from the post-hoc analysis identified that pirfenidone may be an effective treatment in progressive fibrosing uILD over 24 weeks, irrespective of SLB status; however, caution should be taken when interpreting these data due to several limitations. There are differences in the treatment effect of pirfenidone between the subgroups that require further pathological and radiological investigation. In this manuscript, we also descriptively compared baseline characteristics from the overall pirfenidone in uILD study population with other uILD populations reported in the literature, with the aim of understanding if there are any similarities or differences within these cohorts. Most baseline characteristics for patients in the pirfenidone in uILD study were within the ranges reported in the literature; however, ranges were wide, highlighting the heterogeneity of uILD populations.

Deep Learning-based Outcome Prediction in Progressive Fibrotic Lung Disease Using High-resolution Computed Tomography

RATIONALE Reliable outcome prediction in patients with fibrotic lung disease using baseline high-resolution computed tomography (HRCT) data remains challenging. OBJECTIVES To evaluate the prognostic accuracy of a deep learning algorithm (SOFIA), trained and validated in the identification of UIP-like features on HRCT (UIP probability), in a large cohort of well characterised patients with progressive fibrotic lung disease, drawn from a national registry. METHODS SOFIA and radiologist-UIP probabilities were converted to PIOPED-based UIP probability categories (UIP not included in the differential: 0-4%, low probability of UIP: 5-29%, intermediate probability of UIP: 30-69%, high probability of UIP: 70-94%, and pathognomonic for UIP:95-100%) and their prognostic utility assessed using Cox proportional hazards modelling. MEASUREMENTS AND MAIN RESULTS On multivariable analysis adjusting for age, gender, guideline based radiologic diagnosis and disease severity (using total ILD extent on HRCT, %predicted FVC, DLco or the CPI), only SOFIA-UIP probability PIOPED categories predicted survival. SOFIA-PIOPED UIP probability categories remained prognostically significant in patients considered indeterminate (n=83) by expert radiologist consensus (HR1.73, p<0.0001, 95%CI 1.40-2.14). In patients undergoing surgical lung biopsy (SLB) (n=86), after adjusting for guideline-based histologic pattern and total ILD extent on HRCT, only SOFIA-PIOPED probabilities were predictive of mortality (HR1.75, p<0.0001, 95%CI 1.37-2.25). CONCLUSIONS Deep learning-based UIP probability on HRCT provides enhanced outcome prediction in patients with progressive fibrotic lung disease when compared to expert radiologist evaluation or guideline-based histologic pattern. In principle this tool may be useful in multidisciplinary characterisation of fibrotic lung disease. The utility of this technology as a decision support system when ILD expertise is unavailable requires further investigation.

Diffuse alveolar haemorrhage as a rare complication of antiphospholipid syndrome

Diffuse alveolar haemorrhage (DAH) is a rare complication of antiphospholipid syndrome. With a mortality rate of 46%, early diagnosis and management remain an ongoing challenge. Case reports are limited, and management guidelines are not yet definitive. In this case report, we present a 43‐year‐old male with DAH who required high‐dose oral steroids, intravenous methylprednisolone cyclophosphamide and rituximab over 18 months to control life‐threatening episodes of pulmonary bleeding.

Integrating Clinical Probability into the Diagnostic Approach to Idiopathic Pulmonary Fibrosis: An International Working Group Perspective

BACKGROUND

When considering the diagnosis of idiopathic pulmonary fibrosis (IPF), experienced clinicians integrate clinical features that help to differentiate IPF from other fibrosing interstitial lung diseases, thus generating a "pre-test" probability of IPF. The aim of this international working group perspective was to summarize these features using a tabulated approach similar to chest HRCT and histopathologic patterns reported in the international guidelines for the diagnosis of IPF, and to help formally incorporate these clinical likelihoods into diagnostic reasoning to facilitate the diagnosis of IPF.

METHODS

The committee group identified factors that influence the clinical likelihood of a diagnosis of IPF, which was categorized as a pre-test clinical probability of IPF into "high" (70-100%), "intermediate" (30-70%), or "low" (0-30%). After integration of radiological and histopathological features, the post-test probability of diagnosis was categorized into "definite" (90-100%), "high confidence" (70-89%), "low confidence" (51-69%), or "low" (0-50%) probability of IPF.

FINDINGS

A conceptual Bayesian framework was created, integrating the clinical likelihood of IPF ("pre-test probability of IPF") with the HRCT pattern, the histopathology pattern when available, and/or the pattern of observed disease behavior into a "post-test probability of IPF". The diagnostic probability of IPF was expressed using an adapted diagnostic ontology for fibrotic interstitial lung diseases.

INTERPRETATION

The present approach will help incorporate the clinical judgement into the diagnosis of IPF, thus facilitating the application of IPF diagnostic guidelines and, ultimately improving diagnostic confidence and reducing the need for invasive diagnostic techniques.

Pirfenidone in Unclassifiable Interstitial Lung Disease: A Subgroup Analysis by Concomitant Mycophenolate Mofetil and/or Previous Corticosteroid Use

Introduction

There are currently no approved treatments solely for unclassifiable interstitial lung disease (uILD); however, a recent trial showed this population can benefit from pirfenidone. We report a subgroup analysis of this trial to assess the effects of immunomodulators (concomitant mycophenolate mofetil [MMF] and/or previous corticosteroids) with pirfenidone in patients with uILD.

Methods

This was a multicenter, international, double-blind, randomized, placebo-controlled phase II trial of patients with progressive fibrosing uILD (NCT03099187). Patients were randomized (1:1) to receive pirfenidone 2403 mg/day or placebo. This analysis assessed forced vital capacity (FVC) change from baseline measured using site spirometry (key secondary endpoint) and safety over 24 weeks by concomitant MMF use at randomization (pre-specified analysis) and/or previous corticosteroid use (post hoc analysis).

Results

Overall, 253 patients were randomized, including 45 (17.8%) patients (pirfenidone, n = 23; placebo, n = 22) receiving concomitant MMF with/without previous corticosteroids (MMF subgroup); 79 (31.2%) patients (pirfenidone, n = 44; placebo, n = 35) receiving previous corticosteroids without MMF (corticosteroids/no-MMF subgroup); and 129 (51.0%) patients (pirfenidone, n = 60; placebo, n = 69) not receiving concomitant MMF or previous corticosteroids (no-corticosteroids/no-MMF subgroup). At 24 weeks, difference in mean (95% confidence interval) FVC change from baseline between pirfenidone and placebo was − 55.4 mL (− 206.7, 96.0; P = 0.4645) in the MMF subgroup; 128.4 mL (− 6.4, 263.3; P = 0.0617) in the corticosteroids/no-MMF subgroup; and 115.5 mL (35.1, 195.9; P = 0.0052) in the no-corticosteroids/no-MMF subgroup. All subgroups generally exhibited a similar pattern of treatment-emergent adverse events.

Conclusion

Although limited by design and small sample sizes, this analysis suggests pirfenidone may be less effective in patients with uILD receiving concomitant MMF, whereas a beneficial treatment effect was observed in patients not receiving concomitant MMF regardless of previous corticosteroid use. Pirfenidone was well tolerated regardless of MMF and/or corticosteroid use.

Trial Registration Number

ClinicalTrials.gov: NCT03099187.

Detection and Early Referral of Patients With Interstitial Lung Abnormalities: An Expert Survey Initiative

BACKGROUND

Interstitial lung abnormalities (ILA) may represent undiagnosed early-stage or subclinical interstitial lung disease (ILD). ILA are often observed incidentally in patients who subsequently develop clinically overt ILD. There is limited information on consensus definitions for, and the appropriate evaluation of, ILA. Early recognition of patients with ILD remains challenging, yet critically important. Expert consensus could inform early recognition and referral.

RESEARCH QUESTION

Can consensus-based expert recommendations be identified to guide clinicians in the recognition, referral, and follow-up of patients with or at risk of developing early ILDs?

STUDY DESIGN AND METHODS

Pulmonologists and radiologists with expertise in ILD participated in two iterative rounds of surveys. The surveys aimed to establish consensus regarding ILA reporting, identification of patients with ILA, and identification of populations that might benefit from screening for ILD. Recommended referral criteria and follow-up processes were also addressed. Threshold for consensus was defined a priori as ≥ 75% agreement or disagreement.

RESULTS

Fifty-five experts were invited and 44 participated; consensus was reached on 39 of 85 questions. The following clinically important statements achieved consensus: honeycombing and traction bronchiectasis or bronchiolectasis indicate potentially progressive ILD; honeycombing detected during lung cancer screening should be reported as potentially significant (eg, with the Lung CT Screening Reporting and Data System "S-modifier" [Lung-RADS; which indicates clinically significant or potentially significant noncancer findings]), recommending referral to a pulmonologist in the radiology report; high-resolution CT imaging and full pulmonary function tests should be ordered if nondependent subpleural reticulation, traction bronchiectasis, honeycombing, centrilobular ground-glass nodules, or patchy ground-glass opacity are observed on CT imaging; patients with honeycombing or traction bronchiectasis should be referred to a pulmonologist irrespective of diffusion capacity values; and patients with systemic sclerosis should be screened with pulmonary function tests for early-stage ILD.

INTERPRETATION

Guidance was established for identifying clinically relevant ILA, subsequent referral, and follow-up. These results lay the foundation for developing practical guidance on managing patients with ILA.

Defining anti-synthetase syndrome: a systematic literature review

OBJECTIVES

Anti-synthetase syndrome (ASSD) is a heterogeneous autoimmune disease characterised by multi-system involvement with a wide variety of manifestations. Validated classification criteria are necessary to improve recognition and prevent misclassification, especially given the lack of reliable and standardised autoantibody testing. We systematically reviewed the literature to analyse proposed ASSD criteria, characteristics, and diagnostic performance.

METHODS

We searched PubMed and Embase databases (01/01/1984 to 06/11/2018) and the ACR and EULAR meeting abstracts (2017-2018). Sensitivities, specificities, positive, negative likelihood ratios and risk of bias were calculated for ASSD criteria and key variables reported in the literature. We performed meta-analysis when appropriate.

RESULTS

We retrieved 4,358 studies. We found 85 proposed ASSD criteria from a total of 82 studies. All but one study included anti-synthetase autoantibody (ARS) positivity in the ASSD criteria. Most studies required only one ASSD feature plus anti-ARS to define ASSD (n=64, 78%), whereas 16 studies required more than one ASSD variable plus anti-ARS. The only criteria not including anti-ARS positivity required 5 ASSD clinical features. We found limited data and wide variability in the diagnostic performance of each variable and definition proposed in the literature. Given these limitations we only meta-analysed the performance of individual muscle biopsy and clinical variables in diagnosing ASSD, which performed poorly.

CONCLUSIONS

The current ASSD criteria include a variety of serological, clinical, and histological features with wide variability amongst proposed definitions and the performance of these definitions has not been tested. This systematic literature review suggests the need for additional data and consensus-driven classification criteria for ASSD.

Mortality and survival in idiopathic pulmonary fibrosis: a systematic review and meta-analysis

Background

: There are substantial advances in diagnosis and treatment for idiopathic pulmonary fibrosis (IPF), but without much evidence available on recent mortality and survival trends.

Methods

: A narrative synthesis approach was used to investigate the mortality trends, then meta-analyses for survival trends were carried out based on various time periods.

Results

: Six studies reported the mortality data for IPF in 22 countries, and 62 studies (covering 63 307 patients from 20 countries) reported survival data for IPF. Age-standardised mortality for IPF varied from approximately 0.5 to 12 per 100 000 population per year after year 2000. There were increased mortality trends for IPF in Australia, Brazil, Belgium, Canada, Czech Republic, Finland, France, Germany, Hungary, Italy, Lithuania, Netherlands, Poland, Portugal, Spain, Sweden, and UK, while Austria, Croatia, Denmark, Romania, and US showed decreased mortality trends. The overall 3-year and 5-year cumulative survival rates (CSRs) were 61.8% (95% CI, 58.7–64.9; I2=97.1%) and 45.6% (95% CI, 41.5–49.7; I2=97.7%), respectively. Prior to 2010, the pooled 3-year CSRs was 59.9% (95% CI, 55.8–64.1; I2>95.8%), then not significantly (p=0.067) increased to 66.2% (95% CI, 62.9–69.5; I2=92.6%) in the 2010s decade. After excluding three studies in which no patients received antifibrotics after year 2010, the pooled 3-year CSRs significantly (p=0.039) increased to 67.4% (95% CI, 63.9–70.9; I2=93.1%) in the 2010s decade.

Discussion

: IPF is a diagnosis associated with high mortality. There was no observed increasing survival trend for patients with IPF before year 2010, with then a switch to an improvement, which is probably multifactorial.

Phase 2 trial design of BMS-986278, a lysophosphatidic acid receptor 1 (LPA1) antagonist, in patients with idiopathic pulmonary fibrosis (IPF) or progressive fibrotic interstitial lung disease (PF-ILD)

Introduction

Idiopathic pulmonary fibrosis (IPF) and non-IPF, progressive fibrotic interstitial lung diseases (PF-ILD), are associated with a progressive loss of lung function and a poor prognosis. Treatment with antifibrotic agents can slow, but not halt, disease progression, and treatment discontinuation because of adverse events is common. Fibrotic diseases such as these can be mediated by lysophosphatidic acid (LPA), which signals via six LPA receptors (LPA_1–6). Signalling via LPA₁ appears to be fundamental in the pathogenesis of fibrotic diseases. BMS-986278, a second-generation LPA₁ antagonist, is currently in phase 2 development as a therapy for IPF and PF-ILD.

Methods and analysis

This phase 2, randomised, double-blind, placebo-controlled, parallel-group, international trial will include adults with IPF or PF-ILD. The trial will consist of a 42-day screening period, a 26-week placebo-controlled treatment period, an optional 26-week active-treatment extension period, and a 28-day post-treatment follow-up. Patients in both the IPF (n=240) and PF-ILD (n=120) cohorts will be randomised 1:1:1 to receive 30 mg or 60 mg BMS-986278, or placebo, administered orally two times per day for 26 weeks in the placebo-controlled treatment period. The primary endpoint is rate of change in per cent predicted forced vital capacity from baseline to week 26 in the IPF cohort.

Ethics and dissemination

This study will be conducted in accordance with Good Clinical Practice guidelines, Declaration of Helsinki principles, and local ethical and legal requirements. Results will be reported in a peer-reviewed publication.

Trial registration number

NCT04308681.

Incidence, prevalence and mortality of idiopathic pulmonary fibrosis in Australia

BACKGROUND AND OBJECTIVE

Idiopathic pulmonary fibrosis (IPF) is one of the most common forms of interstitial lung diseases. While studies have been conducted in other countries to determine the epidemiological burden of IPF, there is limited information in Australia. Our study aimed to address this gap and generate the first estimates for the mortality, incidence and prevalence of IPF in Australia.

METHODS

Estimates were generated by utilizing the novel Mortality Incidence Analysis Model (MIAMOD) method and software based on the illness-death model. Data inputs included population estimates and mortality data from the Australian Bureau of Statistics (ABS) for the period 1997-2015 and participant data from the Australian IPF Registry (AIPFR). Projections were estimated for a 10-year period up to 2025.

RESULTS

Overall crude and age-standardized estimates for mortality were 5.9 and 6.3 per 100,000 population; incidence, 10.4 and 11.2 per 100,000 population; and prevalence, 32.6 and 35.1 per 100,000 population. Crude and age-standardized mortality, incidence and prevalence increased over the study period; however, they demonstrated a decreasing trend over the projected period. Persons older than 70 years constituted 9% of the population; however, they accounted for approximately 82%-83% of all deaths, incident and prevalent cases. All estimates were higher in males than in females.

CONCLUSION

Our study provides the first estimates for incidence, prevalence and mortality of IPF in Australia. By reporting national estimates for IPF, our study addresses an information gap important for policy, planning and to help optimize the allocation of resources for the management of patients with IPF.

TELO-SCOPE study: a randomised, double-blind, placebo-controlled, phase 2 trial of danazol for short telomere related pulmonary fibrosis

Introduction

Recent discoveries have identified shortened telomeres and related mutations in people with pulmonary fibrosis (PF). There is evidence to suggest that androgens, including danazol, may be effective in lengthening telomeres in peripheral blood cells. This study aims to assess the safety and efficacy of danazol in adults and children with PF associated with telomere shortening.

Methods and analysis

A multi-centre, double-blind, placebo-controlled, randomised trial of danazol will be conducted in subjects aged >5 years with PF associated with age-adjusted telomere length ≤10th centile measured by flow fluorescence in situ hybridisation; or in children, a diagnosis of dyskeratosis congenita. Adult participants will receive danazol 800 mg daily in two divided doses or identical placebo capsules orally for 12 months, in addition to standard of care (including pirfenidone or nintedanib). Paediatric participants will receive danazol 2 mg/kg/day orally in two divided doses or identical placebo for 6 months. If no side effects are encountered, the dose will be escalated to 4 mg/kg/day (maximum 800 mg daily) orally in two divided doses for a further 6 months. The primary outcome is change in absolute telomere length in base pairs, measured using the telomere shortest length assay (TeSLA), at 12 months in the intention to treat population.

Ethics and dissemination

Ethics approval has been granted in Australia by the Metro South Human Research Ethics Committee (HREC/2020/QMS/66385). The study will be conducted and reported according to Standard Protocol Items: Recommendations for Interventional Trials guidelines. Results will be published in peer-reviewed journals and presented at international and national conferences.

Trial registration numbers

NCT04638517; Australian New Zealand Clinical Trials Registry (ACTRN12620001363976p).

Barriers and facilitators to best care for idiopathic pulmonary fibrosis in Australia

BACKGROUND AND OBJECTIVE

In Australia, little is known about delivery of care for people with idiopathic pulmonary fibrosis (IPF). This study examined the organization of IPF care across Australia, how it aligns with guidance for best practice, and identified barriers and facilitators to best care.

METHODS

Data on the organization of IPF care in Australia were collected from public hospitals using a study-specific questionnaire between February and July 2020. Semi-structured telephone interviews were conducted with respiratory physicians from around Australia between April and December 2020. Interviews were transcribed verbatim and thematic analysis was undertaken.

RESULTS

Almost all hospitals (n = 38, 97%) held multidisciplinary meetings (MDMs) for diagnosing IPF, with 90% of multidisciplinary teams including expert respiratory physicians and radiologists; however, rheumatologists, interstitial lung disease nurses and a histopathologist were often not available. More than 90% of institutions had access to oxygen therapy, pulmonary rehabilitation and advanced care planning, but access to psychological support and clinical trials was limited (53% and 58%, respectively). Fifteen respiratory physicians (27% regional) were interviewed. Approaches to diagnosis, treatment and access to referral services were generally consistent with best practice guidance; however, regional respondents reported barriers related to inadequate staffing, lack of a nurse coordinator, inadequate access to clinical trials and funding models. Telehealth technologies were perceived as facilitators to best care.

CONCLUSION

Clinical management of IPF in Australia generally aligns with best practice guidance, but there may be some inequity of access to specialist services, particularly in regional areas, that should be addressed to ensure optimal care for all.

Nailfold capillaroscopy by smartphone-dermatoscope for connective tissue disease diagnosis in interstitial lung disease: a prospective observational study

Nailfold capillaroscopy (NFC) is a non-invasive tool validated for systemic sclerosis diagnosis. The role and interpretation of NFC in interstitial lung disease (ILD) patients for the diagnosis of connective tissue disease associated ILD (CTD-ILD) remains undefined.

In a prospective study, quantitative and qualitative NFC by smartphone-dermatoscope (3M Dermlite-DL4ΤΜ attached to iPhone-6plusΤΜ) was performed in 96 patients with well-defined CTD-ILD (n=27) and non-CTD ILD (n=69; idiopathic interstitial pneumonia n=42, interstitial pneumonia with autoimmune features n=27) by ILD-multidisciplinary meeting. NFC scoring was performed by two independent, blinded specialist rheumatologists. Comprehensive baseline clinical, serological, physiological and radiological data were included. Multivariable models for CTD diagnosis in ILD, comprising nailfold characteristics at empirical thresholds determined by receiver operating characteristic curve analysis and clinical variables, were explored.

In 94 patients with complete NFC data (total 687 images, median eight images per patient from eight digits), low capillary density (<6 capillaries/millimetre), increased giant capillaries (≥3), avascular areas (≥2) and microhaemorrhages all strongly enhanced the discrimination of CTD-ILD from non-CTD ILD (OR 5.00–7.47) independent of clinical covariates. In multivariable analysis, low capillary density and microhaemorrhages were independent predictors of CTD in ILD additional to the risk conferred by serology and radiology. Microhaemorrhages were also a strong predictor of CTD (adjusted OR 13.45, p=0.006) independent of clinical manifestations. All pre-specified qualitative NFC classification schemes identified CTD-ILD (OR range 3.27–8.47).

NFC performed by smartphone-dermatoscope is an accessible, clinically feasible tool that may improve the identification of CTD further to routine clinical assessment of the ILD patient.

Nailfold capillaroscopy by smartphone-dermatoscope is a safe, feasible tool that may improve the identification of connective tissue disease associated with interstitial lung disease beyond routine clinical assessmenthttps://bit.ly/3iLjxUy

Recent trends in pirfenidone and nintedanib use for idiopathic pulmonary fibrosis in Australia

ObjectivesIdiopathic pulmonary fibrosis (IPF) is one of the most common forms of interstitial lung disease presenting in people aged ≥50 years. There is currently no cure for IPF, but two medications (pirfenidone and nintedanib) have been shown to slow the functional decline of the lungs. In 2017, these two medications were listed on the Pharmaceutical Benefits Scheme (PBS) for subsidisation in Australia. This study evaluated local trends in the use of these two medications.MethodsPrescription data for this analysis were obtained from the PBS Item Reports for the period May 2017-May 2020. Population data were extracted from the Australian Bureau of Statistics data cubes. A descriptive approach was used to conduct and report the analysis to illustrate trends in the use of these two medications and associated costs.ResultsThere were 44 010 prescriptions processed for the treatment for IPF in the 3-year period. Nintedanib use was higher than pirfenidone use, accounting for 54% of prescriptions. New South Wales accounted for 35% of the total prescriptions but, when standardised against population size, the Australian Capital Territory accounted for the highest proportion of prescriptions (24%). Prescriptions for nintedanib and pirfenidone were associated with a total cost of A$131 377 951 over the period 2017-20.ConclusionThis study provides initial information on prescription rates, practices and expenditure for pirfenidone and nintedanib. In addition, we provide some insight into possible pharmacological and epidemiological trends based on jurisdictional differences. Together, the results from this study provide a platform for future research given the dearth of information on IPF in Australia.What is known about the topic?Data regarding trends in the utilisation of antifibrotics for the treatment of IPF in Australia are currently limited.What does this paper add?This study demonstrated that nintedanib use was slightly higher than pirfenidone use, and that there were variations in jurisdictional prescribing practices. The highest number of prescriptions and costs were attributable to New South Wales but, when standardised against population size, the Australian Capital Territory had the highest number of prescriptions and costs.What are the implications for practitioners?This study provides some insights into the use of pirfenidone and nintedanib, as well as pharmacoepidemiological trends, in Australia, which is useful for economic evaluation and modelling future health expenditure.

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.

Management of Acute Exacerbation of Idiopathic Pulmonary Fibrosis in Specialised and Non-specialised ILD Centres Around the World

Background: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is a severe complication associated with a high mortality. However, evidence and guidance on management is sparse. The aim of this international survey was to assess differences in prevention, diagnostic and treatment strategies for AE-IPF in specialised and non-specialised ILD centres worldwide.

Material and Methods: Pulmonologists working in specialised and non-specialised ILD centres were invited to participate in a survey designed by an international expert panel. Responses were evaluated in respect to the physicians' institutions.

Results: Three hundred and two (65%) of the respondents worked in a specialised ILD centre, 134 (29%) in a non-specialised pulmonology centre. Similarities were frequent with regards to diagnostic methods including radiology and screening for infection, treatment with corticosteroids, use of high-flow oxygen and non-invasive ventilation in critical ill patients and palliative strategies. However, differences were significant in terms of the use of KL-6 and pathogen testing in urine, treatments with cyclosporine and recombinant thrombomodulin, extracorporeal membrane oxygenation in critical ill patients as well as antacid medication and anaesthesia measures as preventive methods.

Conclusion: Despite the absence of recommendations, approaches to the prevention, diagnosis and treatment of AE-IPF are comparable in specialised and non-specialised ILD centres, yet certain differences in the managements of AE-IPF exist. Clinical trials and guidelines are needed to improve patient care and prognosis in AE-IPF.

Diagnosis of myositis-associated interstitial lung disease: Utility of the myositis autoantibody line immunoassay

OBJECTIVES

The detection of myositis autoantibodies (MA) in patients with interstitial lung disease (ILD) has major implications for diagnosis and management, especially amyopathic and forme frustes of idiopathic inflammatory myositis-associated ILD (IIM-ILD). Use of the MA line immunoblot assay (MA-LIA) in non-rheumatological cohorts remains unvalidated. We assessed the diagnostic performance of the MA-LIA and explored combined models with clinical variables to improve identification of patients with IIM-ILD.

METHODS

Consecutive patients referred to a specialist ILD clinic, with ILD-diagnosis confirmed at multidisciplinary meeting, and MA-LIA performed within six months of baseline were included. Pre-specified MA-LIA thresholds were evaluated for IIM-ILD diagnosis.

RESULTS

A total 247 ILD patients were included (IIM-ILD n = 12, non-IIM connective tissue disease-associated ILD [CTD-ILD] n = 52, idiopathic interstitial pneumonia [IIP] n = 115, other-ILD n = 68). Mean age was 64.8 years, with 45.3% female, mean FVC 75.5% and DLCO 59.2% predicted. MA were present in 13.8% overall and 83.3% of IIM-ILD patients. The most common MA in IIM-ILD and non-IIM ILD patients were anti-Jo-1 (prevalence 40%) and anti-PMScl (29.2%) autoantibodies respectively. The pre-specified low-positive threshold (>10 signal intensity) had the highest discriminative capacity for IIM-ILD (AUC 0.86). Combining MA-LIA with age, gender, clinical CTD-manifestations and an overlap non-specific interstitial pneumonia/organising pneumonia pattern on HRCT improved discrimination for IIM-ILD (AUC 0.96).

CONCLUSION

The MA-LIA is useful to support a diagnosis of IIM-ILD as a complement to multi-disciplinary ILD assessment. Clinical interpretation is optimised by consideration of the strength of the MA-LIA result together with clinical and radiological features of IIM-ILD.

Mortality in combined pulmonary fibrosis and emphysema patients is determined by the sum of pulmonary fibrosis and emphysema

Emphysema is one of the most common pulmonary comorbidities of idiopathic pulmonary fibrosis (IPF), presenting in about one-third of IPF patients [1]. The term combined pulmonary fibrosis and emphysema (CPFE) has been used to describe a potential phenotype characterised by the coexistence of upper lobe-predominant emphysema, lower lobe-predominant fibrosis and relative preservation of lung volumes (forced vital capacity; FVC) in the context of a disproportionately reduced gas transfer (diffusing capacity of the lung for carbon monoxide; D_LCO) [1–3]. With regard to patient survival, it remains unclear whether mortality in patients with CPFE reflects the cumulative effects of two disease processes (emphysema and fibrosis), or whether CPFE represents a distinct disease phenotype where outcome is worse than the sum of disease parts (emphysema and fibrosis).

In patients with combined pulmonary fibrosis and emphysema, emphysema and fibrosis do not have a synergistic effect that results in worsened survival when compared to IPF patients without emphysemahttps://bit.ly/35EJMo6

Cryobiopsy for Identification of Usual Interstitial Pneumonia and Other Interstitial Lung Disease Features. Further Lessons from COLDICE, a Prospective Multicenter Clinical Trial

Rationale: Transbronchial lung cryobiopsy (TBLC) is an emerging technique for interstitial lung disease diagnosis. Good histopathologic agreement between TBLC and surgical lung biopsy (SLB) was demonstrated in the COLDICE (Cryobiopsy versus Open Lung Biopsy in the Diagnosis of Interstitial Lung Disease Alliance) study; however, diagnostic confidence was frequently lower for TBLC than SLB. Objectives: To characterize specific features of TBLC predictive of usual interstitial pneumonia (UIP) in corresponding SLB and to identify clinical indices predictive of biopsy concordance. Methods: The COLDICE study was a prospective, multicenter study investigating diagnostic agreement between TBLC and SLB. The participants underwent both procedures with blinded pathologist analysis of specimens, applying international guideline criteria. The TBLC features predictive of UIP in the paired SLB and predictive features of overall concordance were analyzed. Measurements and Main Results: A total of 65 patients (66.1 ± 9.3 yr; FVC, 84.7 ± 14.2%; Dl_CO, 63.4 ± 13.8%) participated in the COLDICE study. UIP was identified in 33/65 (50.8%) SLB, and 81.5% were concordant with corresponding TBLC (κ, 0.61; 95% confidence interval [CI], 0.38-0.77). The UIP guideline criteria of "predominantly subpleural or paraseptal fibrosis" was infrequently reported in TBLC (8/33, 24.2%), whereas "patchy fibrosis," "fibroblast foci," and the "absence of alternative diagnostic features" were frequently observed in TBLC. The combination of these three features strongly predicted UIP in paired SLB (odds ratio [OR], 23.4; 95% CI, 6.36-86.1; P < 0.0001). Increased numbers of TBLC samples predicted histopathologic concordance with SLB (OR, 1.8; 95% CI, 1.08-3.01; P = 0.03). The predictors of discordance included older age, family history, and radiologic asymmetry. Conclusions: Subpleural and/or paraseptal fibrosis were not essential for diagnosing UIP in TBLC, provided that other guideline criteria features were present. The diagnostic accuracy of TBLC was strengthened when increased numbers of samples were taken. Clinical trial registered with www.anzctr.org.au (ACTRN12615000718549).