Towards the Essence of Progressiveness: Bringing Progressive Fibrosing Interstitial Lung Disease (PF-ILD) to the Next Stage

Multidisciplinary teams in the clinical care of fibrotic interstitial lung disease: current perspectives

Multidisciplinary team (MDT) meetings, involving the integrated collaboration of healthcare professionals, are increasingly used in clinical practice to inform the diagnosis and treatment of interstitial lung diseases (ILDs). Over time, the assessment of patients with ILD has transitioned from discussions among clinicians, radiologists and pathologists to the inclusion of a broader range of clinical data and specialist expertise. Studies have shown that a multidisciplinary approach can have many benefits for the clinical care of patients with ILD by improving the diagnostic confidence for different ILDs and guiding treatment decisions. The utility of MDT discussions for diagnosis, monitoring disease progression and management decisions, will need to be considered based on how it is best positioned in the diagnostic and therapeutic process, as well as the practicality and challenges of its use. There are also uncertainties and heterogeneity concerning the optimal practices of MDT meetings in ILD care. In this review, we describe recent developments refining the approach to MDTs in clinical practice, including who should be involved in the MDTs, when it is most needed, their use in patient management, challenges in their implementation, and ongoing controversies in the field that need further research.

Healthcare Resource Utilization and Related Costs in Chronic Fibrosing Interstitial Lung Diseases with a Progressive Phenotype: A US Claims Database Analysis

INTRODUCTION

We aimed to describe healthcare resource utilization (HCRU) patterns and costs in patients with fibrosing interstitial lung disease (ILD) and those with a progressive phenotype of fibrosing ILD in a US claims database.

METHODS

Data from the IBM^® MarketScan^® databases (1 October 2011-30 September 2015) were used. Diagnosis codes documented on medical claims on two occasions (without any claims during the 12 months prior) identified patients with incident fibrosing ILD. Patients with chronic fibrosing ILD with a progressive phenotype were identified by proxies for progression. Patients aged ≥ 18 years with 365 days of continuous coverage before the index date were eligible for inclusion. Data were analyzed for 12 months prior to identification of fibrosing ILD/progressive phenotype (baseline) and 12 months after (follow-up). Outcomes included treatment patterns, outpatient and inpatient claims, and costs.

RESULTS

We identified 23,577 patients with incident fibrosing ILD and 14,722 with the progressive phenotype. Follow-up data were available for 9986 and 5840 patients, respectively. The most frequent ILD-related medications during baseline were corticosteroids (49.4% and 56.6%). Mean (± standard deviation [SD]) annualized number of outpatient claims was 30.0 (± 26.4) and 34.1 (± 27.7) in the baseline period and 36.2 (± 28.6) and 41.9 (± 30.2) in the follow-up in fibrosing ILD and with a progressive phenotype, respectively. Mean (SD) number of all-cause hospitalizations was 0.5 (± 1.1) and 0.7 (± 1.2) during baseline and 0.6 (± 1.1) and 0.7 (± 1.2) during follow-up. Mean (SD) total costs were $40,907 (± 92,496) and $49,561 (± 98,647) during baseline and $46,157 (± 102,858) and $54,215 (± 116,833) during follow-up. Inpatient mortality during follow-up was 53.50 and 77.44 per 1000 patient-years.

CONCLUSION

HCRU and costs were high in patients with chronic fibrosing ILD with a progressive phenotype, likely reflecting the disease severity and the need for close monitoring and acute care. Outpatient claims accounted for a substantial proportion of the total costs.

The Role of Radiology in Progressive Fibrosing Interstitial Lung Disease

In this article, we describe the role of radiology for diagnosis and follow-up of progressive fibrosing interstitial lung disease (PF-ILD). Patients with PF-ILD are at increased risk for early death without treatment. Clinical diagnosis of PF-ILD has been described in the literature. This manuscript reviews the radiographic diagnosis of PF-ILD and the unique CT characteristics associated with specific types of fibrosis. Ultimately, we believe that radiology has the potential to recognize progression early and thus make an important contribution to the multidisciplinary discussion for this important diagnosis.

Targeting monocytes/macrophages in fibrosis and cancer diseases: Therapeutic approaches

Over almost 140 years since their identification, the knowledge about macrophages has unbelievably evolved. The 'big eaters' from being thought of as simple phagocytic cells have been recognized as master regulators in immunity, homeostasis, healing/repair and organ development. Long considered to originate exclusively from bone marrow-derived circulating monocytes, macrophages have been also demonstrated to be the first immune cells colonizing tissues in the developing embryo and persisting in adult life by self-renewal, as long-lived tissue resident macrophages. Therefore, heterogeneous populations of macrophages with different ontogeny and functions co-exist in tissues. Macrophages act as sentinels of homeostasis and are intrinsically programmed to lead the wound healing and repair processes that occur after injury. However, in certain pathological circumstances macrophages get dysfunctional, and impaired or aberrant macrophage activities become key features of diseases. For instance, in both fibrosis and cancer, that have been defined 'wounds that do not heal', dysfunctional monocyte-derived macrophages overall play a key detrimental role. On the other hand, due to their plasticity these cells can be 're-educated' and exert anti-fibrotic and anti-cancer functions. Therefore macrophages represent an important therapeutic target in both fibrosis and cancer diseases. The current review will illustrate new insights into the role of monocytes/macrophages in these devastating diseases and summarize new therapeutic strategies and applications of macrophage-targeted drug development in their clinical setting.

Defining and predicting progression in non-IPF interstitial lung disease

Randomized placebo-controlled trials demonstrated the efficacy of antifibrotic treatment in non-IPF progressive fibrosing ILD (fILD). Currently, there is no consensus on how progression should be defined and clinical data of non-IPF fILD patients in a real-world setting are scarce. Non-IPF fILD patients presenting at the University Hospitals Leuven between 2012 and 2016 were included. Different definitions of progression according to the selection criteria of the INBUILD, RELIEF and the uILD study were retrospectively evaluated at every hospital visit. Univariate and multivariate analyses were performed to identify predictors of progression and mortality. The study cohort comprised 120 patients; 68.3%, 54.2% and 65.8% had progressive disease based on the INBUILD, RELIEF and uILD study, respectively. A large overlap of progressive fILD patients according to the different clinical trials was observed. Median transplant-free survival time of progressive fILD patients was 3.9, 3.9, 3.8 years and the median time-to-progression after diagnosis was 2.0, 3.1 and 2.3 years according to the INBUILD, RELIEF and uILD study, respectively. We identified several predictors of mortality, but only an underlying diagnosis of HP and uILD was independently associated with progression. Our data show a high prevalence of progressive fibrosis among non-IPF fILD patients and a discrepancy between predictors of mortality and progression. Mortality rate in fILD is high and the identification of progressive disease is only made late during the disease course. Moreover, future treatment decisions will be based upon disease behavior. Therefore, more predictors of progressive disease are needed to guide treatment decisions in the future.

Progressive Fibrosing Interstitial Lung Diseases: A Current Perspective

Interstitial lung diseases (ILDs) are a large and diverse group of rare and chronic respiratory disorders, with idiopathic pulmonary fibrosis (IPF) being the most common and best-studied member. Increasing interest in fibrosis as a therapeutic target and the appreciation that fibrotic mechanisms may be a treatable target of IPF prompted the development and subsequent approval of the antifibrotics, pirfenidone and nintedanib. The management of ILDs has changed considerably following an understanding that IPF and some ILDs share similar disease behavior of progressive fibrosis, termed “progressive fibrosing phenotype”. Indeed, antifibrotic treatment has shown to be beneficial in ILDs characterized by the progressive fibrosing phenotype. This narrative review summarizes current knowledge in the field of progressive fibrosing ILDs. Here, we discuss the clinical characteristics and pathogenesis of lung fibrosis and highlight relevant literature concerning the mechanisms underlying progressive fibrosing ILDs. We also summarize current diagnostic approaches and the available treatments of progressive fibrosing ILDs and address the optimization of treating progressive fibrosing ILDs with antifibrotics in clinical practice.

Biopsy in interstitial lung disease: specific diagnosis and the identification of the progressive fibrotic phenotype

PURPOSE OF REVIEW

The evaluation of progression in fibrotic interstitial lung diseases (ILDs) may require a multidimensional approach. This review will cover the role and usefulness of lung biopsy in diagnosis and assessment of the progressive fibrotic phenotype.

RECENT FINDINGS

The identification of specific findings and the balance between inflammation and fibrosis on lung biopsy may help distinguishing different disease entities and may likely determine the effect of treatment and possibly prognosis. The fibrotic morphological patterns potentially associated with a progressive phenotype include usual interstitial pneumonia (UIP), fibrotic nonspecific interstitial pneumonia, pleuroparenchymal fibroelastosis, desquamative interstitial pneumonia, fibrotic hypersensitivity pneumonitis and other less common fibrotic variants, with histopathological findings of UIP at the time of diagnosis being predictive of worse outcome compared with other patterns. The prognostic significance of lung biopsy findings has been assessed after both surgical lung biopsy (SLB) and transbronchial lung cryobiopsy (TBLC), the latter becoming a valid alternative to SLB, if performed in experienced centres, due to significantly lower morbidity and mortality.

SUMMARY

Lung biopsy plays an important role in diagnosis and identification of the progressive fibrotic phenotype. The introduction of less invasive procedures could potentially expand the role of lung sampling, including for example patients with a known diagnosis of ILD or at an earlier stage of the disease.

Prevalence and Incidence of Chronic Fibrosing Interstitial Lung Diseases with a Progressive Phenotype in the United States Estimated in a Large Claims Database Analysis

INTRODUCTION

Many fibrosing interstitial lung diseases (ILDs) develop a chronic progressive phenotype. While idiopathic pulmonary fibrosis, which is always progressive, is well characterized with established treatment options, the epidemiology of other chronic fibrosing ILDs with a progressive phenotype has not been widely investigated. Treatment options are limited, with a high unmet need. This claims database study estimates the incidence and prevalence of these diseases in the USA.

METHODS

Diagnosis, procedure and resource utilization codes from insurance claims were used to identify patients with fibrosing ILD and those with a chronic progressive phenotype among 37,565,644 adult patients in the IBM® MarketScan® Research Database 2012-2015. Two eligible ILD claims were required for a fibrosing ILD diagnosis. Progression was defined using a novel algorithm constituted by criteria considered proxies for progression. Patients were defined as having incident (new) or existing diagnoses based on claims during a 365-day period before study entry.

RESULTS

The estimated age- and sex-adjusted prevalence per 100,000 persons of fibrosing ILD (95% confidence interval) was 117.82 (116.56, 119.08) and of chronic fibrosing ILDs with a progressive phenotype was 70.30 (69.32, 71.27). The estimated adjusted incidence per 100,000 patient-years of fibrosing ILD was 51.56 (50.88, 52.24) and of chronic fibrosing ILDs with a progressive phenotype was 32.55 (32.01, 33.09). Among incident fibrosing ILD patients, 57.3% experienced progression over a median of 117 days (interquartile range 63-224), with largely comparable rates of progression among different diseases.

CONCLUSIONS

Chronic fibrosing ILDs with a progressive phenotype comprise a relatively new disease construct requiring varied approaches to obtain reliable estimates of prevalence and incidence. This is the first large claims database study using real-world data to provide estimates of the prevalence and incidence of these diseases among a very large segment of the US population and could form the groundwork for future studies.

Chronic hypersensitivity pneumonitis: real world diagnostic criteria

PURPOSE OF REVIEW

Establishing a diagnosis of hypersensitivity pneumonitis (HP) and distinguishing it from other forms of interstitial lung diseases represents a common challenge in clinical practice. This review summarizes the latest literature and guidelines on HP while integrating some real-life conundrums.

RECENT FINDINGS

Advances in the understanding of the pathobiology of fibrotic HP and other progressive pulmonary fibrosis have changed how we approach the diagnosis and treatment of interstitial lung disease. Classifications now embrace distinguishing two clinical phenotypes: nonfibrotic and fibrotic HP because of distinct disease behavior and prognosis implications. International guidelines on HP were recently published and proposed a framework and algorithm to guide the diagnostic process.

SUMMARY

The diagnosis of HP relies on the integration of multiples domains: clinical assessment of exposure, imaging, bronchoalveolar lavage lymphocytosis and histopathological findings. These features are reviewed in multidisciplinary discussion and lead to an estimation of the degree of confidence for HP diagnosis. Further research is warranted to improve knowledge on the pathophysiology of HP and ultimately improve its diagnostic approaches.

Consensus-Statement der Österreichischen Gesellschaften für Pneumologie und Rheumatologie zur Definition, Evaluation und Therapie von progredient fibrosierenden interstitiellen Lungenerkrankungen (pfILD)

Interstitielle Lungenerkrankungen (ILD) sind eine heterogene Gruppe von Pathologien, die zunehmend als relevanter Faktor pulmonaler Morbidität und Mortalität erkannt werden. Verschiedene ILD wie die idiopathische Lungenfibrose (IPF), aber auch durch Autoimmunprozesse oder durch exogene Noxen bedingte ILD können zu progredienter, meist irreversibler Lungenfibrose führen. Die antifibrotischen Substanzen Nintedanib und Pirfenidon können den Krankheitsverlauf bei IPF-Patienten günstig beeinflussen. Dagegen werden ILD, die auf entzündlichen Prozessen wie z. B. rheumatologischen Grunderkrankungen oder exogen-allergischer Alveolitis beruhen, bis dato klassischerweise immunsuppressiv therapiert. Immer wieder kommt es aber trotz einer solchen Behandlung zu progredienter Fibrosierung. Eine positive Wirkung antifibrotischer Medikation auf progredient fibrosierende (pf)ILD abseits der IPF konnte in rezenten Studien demonstriert werden, auch wenn der Stellenwert der Antifibrotika in solchen Situationen noch nicht vollständig geklärt ist. Dieses Consensus-Statement beruht auf einem virtuellen, multidisziplinären Expertenmeeting von Rheumatologen, Pneumologen und Radiologen und wurde durch die jeweiligen ILD-Arbeitskreise der Österreichischen Gesellschaften für Pneumologie sowie Rheumatologie (ÖGP und ÖGR) akkordiert. Ziel war es, den aktuellen Stand von klinischer Praxis und wissenschaftlicher Datenlage zu Definition, Evaluation und Therapie von pfILD darzustellen. Zusammenfassend sollen ILD-Patienten einer standardisierten Abklärung unterzogen, in einem multidisziplinären ILD-Board diskutiert und dementsprechend therapiert werden. Kern dieser Empfehlungen ist, auch Non-IPF-Patienten mit dokumentiert progredient fibrosierendem ILD-Verlauf antifibrotisch zu behandeln, insbesondere wenn Honigwabenzysten oder eine bereits ausgedehnte Erkrankung vorliegen. Patienten mit fibrotischer ILD, die auf Basis der ILD-Board-Empfehlung primär keiner oder ausschließlich einer immunsuppressiven Therapie unterzogen werden, sollten engmaschig hinsichtlich eines progredienten Verlaufes überwacht werden.

Estimation of the Prevalence of Progressive Fibrosing Interstitial Lung Diseases: Systematic Literature Review and Data from a Physician Survey

Some patients with interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis exhibit a progressive clinical phenotype. These chronic progressive fibrosing ILDs have a variety of underlying diseases, and their prevalence is currently unknown. Here we carry out the first systematic review of literature on the prevalence of fibrosing ILDs and progressive fibrosing ILDs using data from physician surveys to estimate frequency of progression among different ILDs. We searched MEDLINE and Embase for studies assessing prevalence of ILD, individual ILDs associated with fibrosis and progressive fibrosing ILDs. These were combined with data from previously published physician surveys to obtain prevalence estimates of each chronic fibrosing ILD with a progressive phenotype and of progressive fibrosing ILDs overall. We identified 16 publications, including five reporting overall ILD prevalence, estimated at 6.3-76.0 per 100,000 people in Europe (four studies) and 74.3 per 100,000 in the USA (one study). In total, 13-40% of ILDs were estimated to develop a progressive fibrosing phenotype, with overall prevalence estimates for progressive fibrosing ILDs of 2.2-20.0 per 100,000 in Europe and 28.0 per 100,000 in the USA. Prevalence estimates for individual progressive fibrosing ILDs varied up to 16.7 per 100,000 people. These conditions represent a sizeable fraction of chronic respiratory disorders and have a high unmet need.

Molecular approach to the classification of chronic fibrosing lung disease-there and back again

Chronic diffuse parenchymal lung disease (DPLD) is an umbrella term for a very heterogeneous group of lung diseases. Over the last decades, clinical, radiological and histopathological criteria have been established to define and separate these entities. More recently the clinical utility of this approach has been challenged as a unifying concept of pathophysiological mechanisms and a shared response to therapy across the disease spectrum have been described. In this review, we discuss molecular motifs for subtyping and the prediction of prognosis focusing on genetics and markers found in the blood, lavage and tissue. As a purely molecular classification so far lacks sufficient sensitivity and specificity for subtyping, it is not routinely used and not implemented in international guidelines. However, a better molecular characterization of lung disease with a more precise identification of patients with, for example, a risk for rapid disease progression would facilitate more accurate treatment decisions and hopefully contribute to better patients' outcomes.

Clinical and Functional Characteristics of Patients with Unclassifiable Interstitial Lung Disease (uILD): Long-Term Follow-Up Data from European IPF Registry (eurIPFreg)

(1) Aim of the study: In spite of extensive research, up to 20% of interstitial lung diseases (ILD) patients cannot be safely classified. We analyzed clinical features, progression factors, and outcomes of unclassifiable ILD (uILD). (2) Methods: A total of 140 uILD subjects from the University of Giessen and Marburg Lung Center (UGMLC) were recruited between 11/2009 and 01/2019 into the European Registry for idiopathic pulmonary fibrosis (eurIPFreg) and followed until 01/2020. The diagnosis of uILD was applied only when a conclusive diagnosis could not be reached with certainty. (3) Results: In 46.4% of the patients, the uILD diagnosis was due to conflicting clinical, radiological, and pathological data. By applying the diagnostic criteria of usual interstitial pneumonia (UIP) based on computed tomography (CT), published by the Fleischner Society, 22.2% of the patients displayed a typical UIP pattern. We also showed that forced vital capacity (FVC) at baseline (p = 0.008), annual FVC decline ≥10% (p < 0.0001), smoking (p = 0.033), and a diffusing capacity of the lung for carbon monoxide (DLco) ≤55% of predicted value at baseline (p < 0.0001) were significantly associated with progressive disease. (4) Conclusions: The most important prognostic factors in uILD are baseline level and decline in lung function and smoking. The use of Fleischner diagnostic criteria allows further differentiation and accurate diagnosis.