A prospective survey of idiopathic interstitial pneumonias in a web registry in Japan

Lung ultrasound for assessing disease progression in UIP and NSIP: a comparative study with HRCT and PFT/DLCO

BACKGROUND

This study aims to compare Lung Ultrasound (LUS) findings with High-Resolution Computerized Tomography (HRCT) and Pulmonary Function Tests (PFTs) to detect the severity of lung involvement in patients with Usual Interstitial Pneumonia (UIP) and Non-Specific Interstitial Pneumonia (NSIP).

METHODS

A cross-sectional study was conducted on 35 UIP and 30 NSIP patients at a referral hospital. All patients underwent LUS, HRCT, and PFT. LUS findings such as B-lines, pleural fragmentation, and pleural thickening were compared with HRCT-based lung involvement and PFT parameters.

RESULTS

In UIP patients, B-lines > 18 and pleural fragmentation significantly differentiated between < 50% and > 50% HRCT involvement. A logistic regression model showed that B-lines > 18 (OR = 39, p = 0.04) and pleural fragmentation (OR = 22, p = 0.037) independently predicted > 50% HRCT involvement. ROC analysis of the model revealed 84.2% sensitivity and 84.5% specificity. Furthermore, the crude number of B-lines (OR = 1.2, p = 0.038) and > 50% HRCT involvement (OR = 9.5, p = 0.045) independently predicted severe DLCO impairment, with a sensitivity of 94.7% and specificity of 84.5%. Linear regression showed that each additional B-line was associated with a 0.4% decrease in DLCO (Beta = -0.377, p = 0.043), independent of patient diagnosis. In NSIP patients, no significant correlation was observed between LUS findings and > 50% HRCT involvement (p > 0.05), though B-line numbers and pleural thickening increased in cases with severe DLCO impairment (p < 0.05).

CONCLUSIONS

LUS shows promise as a sensitive, radiation-free alternative to HRCT in monitoring the severity of UIP. It is particularly valuable in predicting the extent of lung involvement and severe DLCO impairment in UIP patients but has limited application in NSIP.

Current challenges in the diagnosis and management of idiopathic pulmonary fibrosis in Japan

Idiopathic pulmonary fibrosis (IPF) is the archetypal interstitial lung disease. It is a chronic progressive condition that is challenging to manage as the clinical course of the disease is often difficult to predict. The prevalence of IPF is rising globally and in Japan, where it is estimated to affect 27 individuals per 100,000 of the population. Greater patient numbers and the poor prognosis associated with IPF diagnosis mean that there is a growing need for disease management approaches that can slow or even reverse disease progression and improve survival. Considerable progress has been made in recent years, with the approval of two antifibrotic therapies for IPF (pirfenidone and nintedanib), the availability of Japanese treatment guidelines, and the creation of global and Japanese disease registries. Despite this, significant unmet needs remain with respect to the diagnosis, treatment, and management of this complex disease. Each of these challenges will be discussed in this review, including making a timely and differential diagnosis of IPF, uptake and adherence to antifibrotic therapy, patient access to pulmonary rehabilitation, lung transplantation and palliative care, and optimal strategies for monitoring and staging disease progression, with a particular focus on the status in Japan. In addition, the review will reflect upon how ongoing research, clinical trials of novel therapies, and technologic advancements (including artificial intelligence, biomarkers, and genomic classification) may help address these challenges in the future.

Relationship between idiopathic interstitial pneumonias (IIPs) and connective tissue disease-related interstitial lung disease (CTD-ILD): A narrative review

While idiopathic interstitial pneumonia (IIP) centering on idiopathic pulmonary fibrosis (IPF) is the most prevalent interstitial lung disease (ILD), especially in the older adult population, connective tissue disease (CTD)-related ILD is the second most prevalent ILD. The pathogenesis of IPF is primarily fibrosis, whereas that of other ILDs, particularly CTD-ILD, is mainly inflammation. Therefore, a precise diagnosis is crucial for selecting appropriate treatments, such as antifibrotic or immunosuppressive agents. In addition, some patients with IIP have CTD-related features, such as arthritis and skin eruption, but do not meet the criteria for any CTD, this is referred to as interstitial pneumonia with autoimmune features (IPAF). IPAF is closely associated with idiopathic nonspecific interstitial pneumonia (iNSIP) and cryptogenic organizing pneumonia (COP). Furthermore, patients with iNSIP or those with NSIP with OP overlap frequently develop polymyositis/dermatomyositis after the diagnosis of IIP. Acute exacerbation of ILD, the most common cause of death, occurs more frequently in patients with IPF than in those with other ILDs. Although acute exacerbation of CTD-ILD occurs at a low rate of incidence, patients with rheumatoid arthritis, microscopic polyangiitis, or systemic sclerosis experience more acute exacerbation of CTD-ILD than those with other CTD. In this review, the features of each IIP, focusing on CTD-related signatures, are summarized, and the pathogenesis and appropriate treatments to improve the prognoses of patients with various ILDs are discussed.

Developing radiology diagnostic tools for pulmonary fibrosis using machine learning methods

BACKGROUND

Accurate and prompt diagnosis of the different patterns for pulmonary fibrosis is essential for patient management. However, accurate diagnosis of the specific pattern is challenging due to overlapping radiographic characteristics.

MATERIALS AND METHODS

We conducted a retrospective chart review utilizing two machine learning methods, classification and regression tree and Bayesian additive regression tree, to select the most important radiographic features for diagnosing the three most common fibrosis patterns and created an online diagnostic app for convenient implementation.

RESULTS

Four hundred patients (median age of 67 with inter quartile range 58-73; 200 males) were included in the study. Peripheral distribution, homogeneity, lower lobe predominance and mosaic attenuation of fibrosis are the four most important features identified. Bayesian additive regression tree demonstrates better performance than classification and regression tree in diagnosis prediction and provides the predicted probability of each diagnosis with uncertainty intervals for each combination of features.

CONCLUSION

The model and app built with Bayesian additive regression tree can be used as an effective tool in assisting radiologists in the diagnostic process of pulmonary fibrosis pattern recognition.

Design and rationale of the Japanese Idiopathic Interstitial Pneumonias (JIPS) Registry

BACKGROUND

Numerous studies investigated patients with IPF; however, only a few examined patients with idiopathic interstitial pneumonias (IIPs).

METHODS

The Japanese Idiopathic Interstitial Pneumonias (JIPS) Registry, which was initiated in December 2016, is a multicenter prospective observational study of patients newly diagnosed with IIPs from 86 facilities treating ILDs. The plan is to enroll more than 600 new patients during the 2-year enrolment period and to follow their progress for 3 years after the last case enrolment. If additional consent is obtained, the study will continue for another 2 years. Research questions mainly focus on identifying the frequency by IIP classification, patient background, and diagnostic methods during enrolment, survival, acute exacerbation rate, changes in high-resolution CT imaging, forced vital capacity, and interstitial pneumonia markers over time. Other research questions, including those regarding disease behavior in patients with progressive fibrosing-ILD and new biomarkers associated with genetic predispositions, will be investigated.

DISCUSSION

The JIPS Registry will provide a comprehensive description of the disease progression, prognosis, treatment status, new biomarkers, and validity of guidelines and central multidisciplinary decisions for IPF and similar diseases that can be differentiated from IPF among IIPs.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the institutional review board of Kanagawa Cardiovascular and Respiratory Center (KCRC-16-0005), and that of Jichi Medical University approved the biobank part (I18-005). Results will be published in peer-reviewed journals and will be presented at national and international conferences.

TRIAL REGISTRATION

ClinTrials.gov Registry (NCT03041623, first posted on February 3, 2017).

Current treatment status of patients with idiopathic pulmonary fibrosis in Japan based on a claims database analysis

BACKGROUND

Treatment for idiopathic pulmonary fibrosis (IPF) has changed over the past decades. Understanding the actual status of IPF treatment and evaluating the consistency of the guidelines are important for improving the treatment strategy. However, the relevant information is insufficient in Japan. Therefore, this study investigated the treatment status and changes in the treatment of patients with IPF in Japan.

METHODS

This retrospective claims-based study used a Japanese claims database that included data from acute care hospitals (April 2008-March 2019). Patients with at least one record of definitive IPF diagnosis were classified as patients with IPF. We determined the percentage of patients who received each treatment type by the year.

RESULTS

We analyzed 9961 patients with IPF. The mean (standard deviation) age at first diagnosis was 74.4 (9.3) years, and 74.9% of the patients were men. The number of patients who did not take any drug treatment tended to decrease over the years. Nevertheless, approximately 30% of the patients did not take any drug treatment in recent years. The number of patients who received antifibrotic drugs increased over time, and it became the most popular treatment for ≥40% of the patients in and after 2017. Although steroid prescriptions tended to decrease over time, they were still administered to one-third of the patients with IPF who received drug treatment in and after 2017.

CONCLUSIONS

Our findings suggest that changes in the IPF treatment reflect changes in guideline recommendations as well as the availability of treatment in clinical settings in Japan.

Changes in Oxygenation and Serological Markers in Acute Exacerbation of Interstitial Lung Disease Treated with Polymyxin B Hemoperfusion

Background: Polymyxin B direct hemoperfusion (PMX-DHP) has been tried in acute exacerbation of interstitial lung disease (AE-ILD) patients and has shown clinical benefit. In this study, we tried to investigate the change in oxygenation and serologic markers after PMX-DHP treatment in AE-ILD patients in Korea. Methods: We reviewed the medical records of twenty-two patients who were admitted for AE-ILD and underwent PMX-DHP treatment. Changes in vital signs and laboratory findings before and after treatment were compared and factors related to 90-day mortality were analyzed using the Cox regression model. Results: Of the 22 included patients, 11 (50%) patients were diagnosed with idiopathic pulmonary fibrosis. In AE-ILD patients treated with PMX-DHP, the 28-day mortality rate was 45.5% and the 90-day mortality rate was 72.7%. The P/F ratio before and after PMX-DHP treatment significantly improved in patients from baseline to 24 h (median (IQR), 116.3 (88.5–134.3) mmHg vs. 168.6 (115.5–226.8) mmHg, p = 0.001), and 48 h (116.3 (88.5–134.3) mmHg vs. 181.6 (108.9–232.0) mmHg, p = 0.003). Also, white blood cells (WBCs) and C-reactive protein (CRP) were decreased after PMX-DHP treatment. High acute physiology and chronic health evaluation II scores were associated with 90-day mortality. Conclusions: In patients with AE-ILD, PMX-DHP treatment was associated with an improved P/F ratio and lower WBC and CRP levels.

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 ∼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, the Netherlands, Poland, Portugal, Spain, Sweden and UK, while Austria, Croatia, Denmark, Romania and the USA 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 CSR 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.

Novel Artificial Intelligence-based Technology for Chest Computed Tomography Analysis of Idiopathic Pulmonary Fibrosis

RATIONALE

There is a growing need to accurately estimate the prognosis of idiopathic pulmonary fibrosis (IPF) in clinical practice, given the development of effective drugs for treating IPF.

OBJECTIVE

To develop artificial intelligence-based image analysis software to detect parenchymal and airway abnormalities on chest computed tomography (CT) and to explore their prognostic importance in patients with IPF.

METHODS

A novel artificial intelligence-based quantitative CT image analysis software (AIQCT) was developed by applying 304 HRCT scans from patients with diffuse lung diseases as the training set. AIQCT automatically categorized and quantified ten types of parenchymal patterns as well as airways, expressing the volumes as percentages of the total lung volume. To validate the software, the area percentages of each lesion quantified by AIQCT were compared with those of the visual scores using 30 plain HRCT images with lung diseases. In addition, three-dimensional analysis for similarity with ground truth was performed using HRCT images from 10　patients with IPF. AIQCT was then applied to 120 patients with IPF who underwent chest HRCT scanning at our institute. Associations between the measured volumes and survival were analyzed.

RESULTS

The correlations between AIQCT and the visual scores were moderate to strong (correlation coefficient 0.44 to 0.95) depending on the parenchymal pattern. The Dice indexes for similarity between AIQCT data and ground truth were 0.67, 0.76, and 0.64 for reticulation, honeycomb, and bronchi, respectively. During a median follow-up period of 2,184 days, 66 patients died, and 1 underwent lung transplantation. In multivariable Cox regression analysis, bronchial volumes [adjusted hazard ratio (HR), 1.33; 95% confidence interval (CI), 1.16 to 1.53] and normal lung volumes (adjusted HR, 0.97; 95% CI, 0.94 to 0.99) were independently associated with survival after adjusting for the GAP stage of IPF.

CONCLUSIONS

Our newly developed artificial intelligence-based image analysis software successfully quantified parenchymal lesions and airway volumes. Bronchial and normal lung volumes on chest HRCT may provide additional prognostic information on the GAP stage of IPF.

The Pulmonary Fibrosis Foundation Patient Registry. Rationale, Design, and Methods

Detailed understanding of longitudinal behavior, response to therapy, and applicable biomarkers for interstitial lung diseases (ILDs) is lacking. There is a need for a large multicenter registry that provides researchers and clinicians access to well-characterized data not limited to patients with idiopathic pulmonary fibrosis. The Pulmonary Fibrosis Foundation Patient Registry (PFF-PR) is a database that collects baseline and longitudinal demographic and clinical information about patients with ILDs in the United States. The objective of this study is to describe the patient population, data collection process, and opportunities for retrospective and prospective research with the PFF-PR. Individuals 18 years or older who had ILD diagnosed and who were seen at PFF-PR centers who provided informed consent were eligible to participate. Baseline and longitudinal demographic, spirometric, radiographic, morbidity, and mortality data are recorded into a secure electronic data capture system. Starting in 2016, the PFF-PR has collected data on 2,003 patients at 42 clinical sites in the United States. At the time of enrollment, the mean age of participants was 68 years old. Most (62%) of participants were male, and 58% had a positive smoking history. The mean forced vital capacity was 69% predicted, and the mean diffusing capacity of the lung for carbon monoxide was 43% predicted. Forty-one percent of patients were using supplemental oxygen, and 39% were on antifibrotic therapy. Reasons for attrition were mostly death or transplant, with low rates of loss to follow-up or withdrawal. The PFF-PR is a large multicenter United States-based registry that provides researchers and clinicians access to well-characterized ILD patient data.

Understanding idiopathic pulmonary fibrosis - Clinical features, molecular mechanism and therapies

Idiopathic pulmonary fibrosis (IPF) is a chronic lung fibrosing disease with high prevalence that has a prognosis worse than many cancers. There has been a recent influx of new observations aimed at explaining the mechanisms responsible for the initiation and progression of pulmonary fibrosis. However, despite this, the pathogenesis of the disease is largely unclear. Recent progress has been made in the characterization of specific pathologic and clinical features that have enhanced the understanding of pathologically activated molecular pathways during the onset and progression of IPF. This review highlights several of the advances that have been made and focus on the pathobiology of IPF. The work also details the different factors that are responsible for the disposition of the disease - these may be internal factors such as cellular mechanisms and genetic alterations, or they may be external factors from the environment. The changes that primarily occur in epithelial cells and fibroblasts that lead to the activation of profibrotic pathways are discussed in depth. Finally, a complete repertoire of the treatment therapies that have been used in the past as well as future medications and therapies is provided.

What parameters can be used to identify early idiopathic pulmonary fibrosis?

Elucidating the disease process of early idiopathic pulmonary fibrosis (IPF) will help clinicians in addressing the contentious issues of when and in which patients, therapeutic intervention should be initiated. Here, we discuss several possible parameters for diagnosing early IPF and their clinical impacts. Physiologically, early IPF can be considered as IPF with normal or mild impairment in pulmonary function. Radiologically, early IPF can be considered as IPF with a small extent and/or early features of fibrosis. Symptomatically, early IPF can be considered as asymptomatic or less symptomatic IPF. IPF at Gender-Age-Physiology index stage I can be considered early IPF. Interstitial lung abnormalities are defined as parenchymal abnormalities in more than 5% of the lung in patients with no prior history of interstitial lung disease, and in some cases, this seems to be equivalent to early IPF. Previous clinical trials showed the effect of antifibrotic therapies in early IPF, but the effects of therapy are uncertain in early IPF outside of clinical trials, such as in cases of IPF with normal pulmonary function, IPF without honeycombing or traction bronchiectasis, and asymptomatic IPF. Moreover, little has been reported on disease progression in such conditions. Because the conceptual framework of early IPF may vary depending on its definition, not only is a diagnosis of early IPF important but prediction of disease progression is also crucial. Further investigations are needed to identify biomarkers that can detect patients who may experience greater degrees of disease progression and require treatment even with those forms of early IPF.

Cytokine Adsorption to Polymyxin B-Immobilized Fiber: An in vitro Study

BACKGROUND

Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) are episodes of acute respiratory worsening characterized by diffuse alveolar damage superimposed on usual interstitial pneumonia. Direct hemoperfusion with a polymyxin B-immobilized fiber column (PMX-DHP) is reported to have beneficial effects on the respiratory status and outcome in patients with AE-IPF although its mechanism of action is not fully elucidated.

OBJECTIVE

To investigate whether and how the PMX-immobilized fiber (PMX-F) adsorbs cytokines because reduction of the serum levels of various cytokines has been noted in AE-IPF patients receiving PMX-DHP.

METHODS

The propensity of recombinant cytokines for adsorption onto PMX-F was examined by incubating cytokines with heparin-coated or uncoated PMX-F for 2 h at 37°C. Cytokines were quantitated by multiplex bead array assay or ELISA.

RESULTS

Interleukin (IL)-8, RANTES, platelet-derived growth factor-bb, and transforming growth factor-β were substantially adsorbed onto PMX-F without heparin coating. The adsorbed cytokines could be eluted with PMX sulfate, indicating that the PMX moiety is involved in cytokine adsorption. Importantly, although IL-1β, monocyte chemoattractant protein-1, fibroblast growth factor 2, and vascular endothelial growth factor-A were adsorbed onto PMX-F to lesser extents, the adsorption was enhanced by heparin coating of PMX-F. Furthermore, heparin-coated PMX-F acquired the capability to adsorb IL-6, IL-12, and tumor necrosis factor α. An affinity of heparin to PMX was determined (Kd = 0.061 ± 0.032 mg/mL), which accounts for the enhanced cytokine adsorption onto PMX-F upon heparin coating.

CONCLUSIONS

Various cytokines involved in inflammation, fibrosis, and vascular permeability were shown to be adsorbed onto PMX-F. Removal of multiple cytokines may be associated with positive impacts of PMX-DHP in patients with AE-IPF.

Clinical impact of the radiological indeterminate for usual interstitial pneumonia pattern on the diagnosis of idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease associated with significant morbidity and mortality. The international clinical practice guidelines for the diagnosis of IPF have recently been revised.

METHODS

In this single-center retrospective study conducted between June 2006 and March 2018, 27 patients with a newly classified indeterminate for usual interstitial pneumonia (UIP) pattern on high-resolution computed tomography (HRCT) who had undergone surgical lung biopsy were enrolled at the Japanese Red Cross Medical Center. Clinical and pathological characteristics and prognosis were retrospectively analyzed from patient records.

RESULTS

On the basis of multidisciplinary discussion (MDD), IPF was diagnosed in six patients (22%), unclassifiable interstitial pneumonia in 5 (19%), chronic hypersensitivity pneumonitis in 10 (37%), collagen vascular disease-associated interstitial lung disease in 5 (19%), and lymphoproliferative disorder in 1 (4%) patient. Ground-glass opacity, peribronchovascular distribution, upper or middle lobe distribution, mosaic attenuation, consolidation patterns, and honeycombing were found on HRCT. Histological UIP or probable UIP was observed in seven patients. The median survival time from the initial visit was 2770 days (92.3 months). There was a significant difference in survival time in the GAP stage and honeycombing on HRCT according to the log-rank test.

CONCLUSIONS

Patients with an indeterminate for UIP pattern on HRCT were more likely to have non-IPF than IPF through pathological diagnosis and MDD. GAP stage and honeycombing on HRCT may be significant risk factors for all-cause mortality.

The similarities and differences between pleuroparenchymal fibroelastosis and idiopathic pulmonary fibrosis

The idiopathic form of pleuroparenchymal fibroelastosis (PPFE) is categorized as a rare idiopathic interstitial pneumonia in the current classification. The majority of PPFE cases are idiopathic, but many predisposing factors or comorbidities have been reported. Although histological PPFE is predominantly located in the upper lobes, which are less often affected by fibrosis in patients with idiopathic pulmonary fibrosis (IPF), the clinical course of PPFE is seemingly similar to that of IPF. However, upper lobe fibroelastosis has various clinical and physiological characteristics that differ from those of IPF, including a flattened thoracic cage and a marked decrease in the forced vital capacity (FVC) but with a preserved residual volume. Compared with IPF, the decrease in the walking distance is mild despite the markedly decreased FVC in PPFE, and chest radiograph more frequently shows the elevation of bilateral hilar opacities with or without tracheal deviation. The prognosis may be related to the development of fibrosing interstitial pneumonia in the lower lobes with elevated levels of serum Krebs von den Lungen-6; however, there is marked variation in the pathogenesis and clinical features in PPFE. A proposal of the diagnostic criteria for idiopathic PPFE with and without surgical lung biopsy, which has recently been published, may be useful.

Prognosis of idiopathic pulmonary fibrosis without anti-fibrotic therapy: a systematic review

In addition to facilitating healthcare delivery planning, reliable information about prognosis is essential for treatment decisions in patients with idiopathic pulmonary fibrosis (IPF). This review aimed to evaluate the prognosis of patients with IPF without anti-fibrotic therapy. We included all cohort studies and the placebo arms of randomised controlled trials (RCTs) in IPF and follow-up of ≥12 months. Two reviewers independently evaluated studies for inclusion, assessed risk of bias and extracted data. A total of 154 cohort studies and 16 RCTs were included. The pooled proportions of mortality were 0.12 (95% CI 0.09–0.14) at 1–2 years, 0.38 (95% CI 0.34–0.42) between 2–5 years, and 0.69 (95% CI 0.59–0.78) at ≥5 years. The pooled mean overall survival was 4 years (95% CI 3.7–4.6) for studies with a follow-up duration of 10 years. At <2 years, forced vital capacity and diffusing capacity of the lung for carbon monoxide declined by a mean of 6.76% predicted (95% CI −8.92 −4.61) and 3% predicted (95% CI −5.14 −1.52), respectively. Although heterogeneity was high, subgroup analyses revealed lower pooled proportions of mortality at 1 year in the RCT participants (0.07 (95% CI 0.05–0.09)) versus cohort study participants (0.14 (95% CI 0.12–0.17)). This review provides comprehensive information on the prognosis of IPF, which can inform treatment discussions with patients and comparisons for future studies with new therapies.

Without anti-fibrotic therapy, patients with IPF have a mortality rate of 31% at ≥5 years, and a mean overall survival of 4 years over 10 years of follow-uphttp://bit.ly/2SDiZSb

Characteristics of tobacco-related lung diseases in Fukuoka Prefecture, Japan: A prospective, multi-institutional, observational study

BACKGROUND

Tobacco smoking causes a variety of smoking-related diseases, death, and economic damage. Despite targeted anti-smoking campaigns, tobacco-related deaths are expected to increase in Japan. We investigated the current state of non-cancerous lung diseases such as idiopathic interstitial pneumonias (IIPs), chronic obstructive pulmonary disease (COPD), and combined pulmonary fibrosis and emphysema (CPFE), which are known to be highly related to tobacco smoking.

METHODS

This prospective multi-institutional observational study involved 29 major hospitals within the Fukuoka Prefecture area (Fukuoka tobacco-related lung disease registry study group). Patients diagnosed with IIPs, including CPFE and COPD, registered from September 1, 2013 to April 30, 2016 were included. Clinical background information, laboratory and pulmonary function test results, findings of imaging tests, including chest radiography and chest computed tomography, and DNA isolated from peripheral blood were collected from each patient. Follow-up surveillance involved collection of data regarding the exacerbation of disease and death until 5 years of registration. In the present study, we report the baseline characteristics of the patients registered in this surveillance study.

RESULTS

Overall, 1016 patients (524 with IIPs, including 145 CPFE and 492 with COPD) were enrolled. Among the patients with COPD, 96.8% were current or former smokers. Among the patients with IIPs, 69.9% were current or former smokers.

CONCLUSION

This study revealed the current status of lung diseases potentially related to tobacco smoking in Fukuoka Prefecture. Both COPD and CPFE were highly related to tobacco smoking, whereas 30% of patients with IIPs had never smoked.

Evaluation and management of Idiopathic Pulmonary Fibrosis

Idiopathic Pulmonary Fibrosis (IPF) is a most common progressive interstitial lung disease (ILD) of unknown etiology, although majority of patients are elderly male smokers. The main pathogenesis is aberrant recovery of epithelial injury and collagen deposition. Fibrotic nonspecific interstitial pneumonia, connective tissue disease (CTD) especially rheumatoid arthritis (RA) associated ILD, and chronic hypersensitivity pneumonia(CHP) are important differential diagnosis. Main symptoms are non-productive cough and progressive exertional dyspnea. Crucial physical findings are scalene muscle hypertrophy, bibasilar fine crackles, and finger clubbing. The serum markers such as lactate dehydrogenase (LDH) and Krebs von den Lungen-6 (KL-6) are sensitive for ILD detection and activity. Both pulmonary function test (PFT) and the 6-minute walk test (6MWT) are useful tool for evaluation of disease progression of IPF. Serial changes of forced vital capacity (FVC) and 6MWT distance predict mortality in IPF effectively. Recently published international IPF guidelines highlight the importance of chest high resolution computed tomography (HRCT) findings such as honeycombing, traction bronchiectasis (TBE), and sub-pleural reticular opacity. IPF is chronic and progressive; therefore, tracking disease behavior is crucial. Unifying clinical, physiological, and imaging information over time is useful. With regard to its management, two anti-fibrotic drugs such as pirfenidone and nintedanib have been available. These drugs can slow the decline of FVC and prevent acute exacerbation (AE). In this review, I outline the clinical characteristics of IPF, physiological, imaging, pathological findings and review diagnosis process and management.

Pleuroparenchymal fibroelastosis diagnosed by multidisciplinary discussions in Japan

BACKGROUND

Pleuroparenchymal fibroelastosis (PPFE) is a rare subset of idiopathic interstitial pneumonias. No large-scale clinical studies of PPFE have been published. The aim of the study was to clarify the clinical and physiological characteristics of PPFE in Japan METHODS: This was a retrospective, nationwide, and multicenter study in Japan. We reviewed 52 patients with PPFE, diagnosed after multidisciplinary discussions.

RESULTS

Flat chest index, defined as the ratio of anteroposterior diameter to transverse diameter of thoracic cage at the level of 6th thoracic vertebra, correlated positively with body mass index (BMI) (r = 0.340, p = 0.013) and percentage of predicted value of forced vital capacity (FVC %pred) (r = 0.355, p = 0.012), and negatively with the ratio of residual volume to total lung capacity (RV/TLC) (r = -0.312, p = 0.042). RV/TLC correlated negatively with BMI (r = -0.746, p < 0.0001) and FVC %pred (r = -0.507, p = 0.0005), and positively with age, and physiological variables (GAP) scores (r = 0.332, p = 0.030). The median survival time and the cumulative 5-year survival rate were 96 months and 58%, respectively. Patients with KL-6 level >600 (U/mL) survived shorter than those with <600 (p < 0.001).

CONCLUSION

Low BMI, decreased FVC and increased RV/TLC in PPFE may be related to the progression of flattened chest cage which impairs distension of chest cage at inspiration. Elevated serum levels of KL-6 suggest a poor prognosis of PPFE.

Gene expression profiling of idiopathic interstitial pneumonias (IIPs): identification of potential diagnostic markers and therapeutic targets

BACKGROUND

Chronic fibrosing idiopathic interstitial pneumonia (IIP) is characterized by alveolar epithelial damage, activation of fibroblast proliferation, and loss of normal pulmonary architecture and function. This study aims to investigate the genetic backgrounds of IIP through gene expression profiling and pathway analysis, and to identify potential biomarkers that can aid in diagnosis and serve as novel therapeutic targets.

METHODS

RNA extracted from lung specimens of 12 patients with chronic fibrosing IIP was profiled using Illumina Human WG-6 v3 BeadChips, and Ingenuity Pathway Analysis was performed to identify altered functional and canonical signaling pathways. For validating the results from gene expression analysis, immunohistochemical staining of 10 patients with chronic fibrosing IIP was performed.

RESULTS

Ninety-eight genes were upregulated in IIP patients relative to control subjects. Some of the upregulated genes, namely desmoglein 3 (DSG3), protocadherin gamma-A9 (PCDHGA9) and discoidin domain-containing receptor 1 (DDR1) are implicated in cell-cell interaction and/or adhesion; some, namely collagen type VII, alpha 1 (COL7A1), contactin-associated protein-like 3B (CNTNAP3B) and mucin-1 (MUC1) are encoding the extracellular matrix molecule or the molecules involved in cell-matrix interactions; and the others, namely CDC25C and growth factor independent protein 1B (GFI1B) are known to affect cell proliferation by affecting the progression of cell cycle or regulating transcription. According to pathway analysis, alternated pathways in IIP were related to cell death and survival and cellular growth and proliferation, which are more similar to cancer than to inflammatory response and immunological diseases. Using immunohistochemistry, we further validate that DSG3, the most highly upregulated gene, shows higher expression in chronic fibrosing IIP lung as compared to control lung.

CONCLUSION

We identified several genes upregulated in chronic fibrosing IIP patients as compared to control, and found genes and pathways implicated in cancer, rather than in inflammatory or immunological disease to play important roles in the pathogenesis of IIPs. Moreover, DSG3 is a novel potential biomarker for chronic fibrosing IIP with its significantly high expression in IIP lung.

Idiopathic pulmonary fibrosis in East Asian

Idiopathic pulmonary fibrosis (IPF) is a rare lung disease with a prognosis that can be worse than that of many cancers. Recent studies have improved our understanding of IPF and new treatment options have become available. However, most studies are conducted predominantly in Western countries while few are conducted in East Asian countries. The distribution, effectiveness of treatment, and prognosis for IPF differ among Westerners and East Asians, but whether the heterogeneity of IPF in East Asians is the result of ethnic differences and geographic variability is unclear. This study highlights the current prevalence of IPF and its characteristics in the East Asian population and it provides valuable information to understand the current clinical status of patients with IPF in light of recent advances in its diagnosis and treatment.

Clinical Course and Changes in High-Resolution Computed Tomography Findings in Patients with Idiopathic Pulmonary Fibrosis without Honeycombing

Some patients with idiopathic pulmonary fibrosis (IPF) do not have honeycombing on high-resolution computed tomography (HRCT) at their initial evaluation. The clinical course and sequential changes in HRCT findings in these patients are not fully understood. We reviewed the cases of 43 patients with IPF without honeycombing on initial HRCT from institutions throughout Japan. All patients were diagnosed with IPF based on a surgical lung biopsy. Multidisciplinary discussions were held five times between 2011 and 2014, to exclude alternative etiologies. We evaluated the sequential changes in HRCT findings in 30 patients with IPF. We classified these 30 patients into three groups based on their HRCT patterns and clarified the clinical characteristics and prognosis among the groups. The patterns of all 30 patients on initial HRCT corresponded to a possible usual interstitial pneumonia (UIP) pattern which was described in the 2011 International Statement. On long-term follow-up (71.0±38.7 standard deviation [SD] months), honeycombing was seen in 16 patients (53%, the HoneyCo group); traction bronchiectasis or cysts without honeycombing was observed in 12 patients (40%, the NoHoneyCo group), and two patients showed no interval change (7%, the NoChange group) on HRCT. The mean survival periods of the HoneyCo and NoHoneyCo groups were 67.1 and 61.2 months, respectively (p = 0.76). There are some patients with IPF whose conditions chronically progress without honeycombing on HRCT. The appearance of honeycombing on HRCT during the follow-up might not be related to prognosis.

Idiopathic Pulmonary Fibrosis: Diagnosis and Clinical Manifestations

Idiopathic pulmonary fibrosis (IPF) is a parenchymal lung disease characterized by progressive interstitial fibrosis. The clinical course of IPF can be unpredictable and may be punctuated by acute exacerbations. Although much progress is being made in unraveling the mechanisms underlying IPF, effective therapy for improving survival remains elusive. Longitudinal disease profiling, especially in terms of clinical manifestations in a large cohort of patients, should lead to proper management of the patients and development of new treatments for IPF. Appropriate multidisciplinary assessment in ongoing registries is required to achieve this. This review summarizes the current status of the diagnosis and clinical manifestations of IPF.

Subgroup analysis of Asian patients in the INPULSIS® trials of nintedanib in idiopathic pulmonary fibrosis

BACKGROUND AND OBJECTIVE

In the two-replicate randomized Phase III INPULSIS® trials in patients with idiopathic pulmonary fibrosis (IPF), nintedanib 150 mg bd significantly reduced the annual rate of decline in forced vital capacity (FVC) compared with placebo. The key secondary endpoints were time to first investigator-reported acute exacerbation and change from baseline in St George's Respiratory Questionnaire total score, both over 52 weeks. Here, we assessed the effect of nintedanib in Asian patients.

METHODS

Pre-specified subgroup analyses of the effect of nintedanib on the primary and key secondary endpoints in Asian versus White patients were undertaken based on pooled data from the two INPULSIS® trials. Safety data were analyzed descriptively.

RESULTS

Of the treated patients, 322 were Asian (nintedanib n = 194; placebo n = 128) and 608 were White (nintedanib n = 360; placebo n = 248). In Asian patients, the nintedanib versus placebo difference in the adjusted annual rate of decline in FVC was 94.1 mL/year (95% CI: 33.7, 154.6). The treatment effect of nintedanib on the annual rate of decline in FVC in Asian and White patients was similar (treatment-by-subgroup interaction P = 0.72) and consistent with the overall population. No significant treatment-by-subgroup interaction was observed for the key secondary endpoints between Asian and White patients. In Asian patients, the most common adverse event in the nintedanib group was diarrhoea (56.2% of patients vs 15.6% for placebo).

CONCLUSION

In pre-specified subgroup analyses of Asian versus White patients with IPF in the INPULSIS® trials, race did not influence the effect of nintedanib on disease progression.

Effect of Renshen Pingfei Decoction, a traditional Chinese prescription, on IPF induced by Bleomycin in rats and regulation of TGF-β1/Smad3

AIM OF THE STUDY

Idiopathic pulmonary fibrosis (IPF), one of the clinical common diseases, shares similar pathogenesis with ancient disease "Feibi" in Chinese medicine, Renshen pingfei decoction (RPFS), a classical prescription, was commonly used in treating Feibi. In the current study, the protective role of RPFS in rats model of IPF and the mechanism via regulation of TGF-β1/Smad3, were evaluated and explored.

METHODS

The chemicals of RPFS were analyzed by UPLC-QTOF-MS. Under the optimized chromatographic and MS condition, the major components in RPFS were well separated and detected. An IPF model was established in rats which were induced with Bleomycin (BLM). After treated with corresponding medicine for 7 days, 14 days, 21 days and 28 days respectively, lung function of rats were measured; peripheral blood and bronchoalveolar lavage fluid (BALF) were assessed; histopathological changes and homogenate of lung tissue were detected; TGF-β1 and Smad3 mRNA and protein expressions in lung tissue were examined as well.

RESULTS

43 signal peaks of chemical components in RPFS were identified by UPLC-QTOF-MS method. Compared with model group, RPFS group exerted significant effects on IPF model rats in improving lung function and decreasing HYP content of lung tissue (P<0.01), reducing the level of TGF-β1 and NFκB in BALF (P<0.05), decreasing SOD and MDA level in serum (P<0.01), as well as down-regulating TGF-β1 and Smad3 mRNA and protein expressions of lung tissue (P<0.01).

CONCLUSION

RPFS could reduce the lung injury and fibrosis degree and improve lung function of IPF model rats. The protective role might mediated by down-regulating TGF-β1/Smad3 signaling pathway.

Pirfenidone: Clinical trials and clinical practice in patients with idiopathic pulmonary fibrosis

Pirfenidone is an oral drug that exerts not only anti-fibrotic activity but also pleiotropic effects, such as anti-inflammatory and anti-oxidative effects. Because it suppresses reduction in vital capacity and improves progression-free survival, it was approved in October 2008 in Japan for the first time in the world as an anti-fibrotic agent for treatment of idiopathic pulmonary fibrosis (IPF). In October 2014, the agent was approved in the U.S., based on the results of the ASCEND study. Today, it is commercially available in 38 countries worldwide. In clinical practice, it is important to pay attention to the balance between the effectiveness and adverse events (such as gastrointestinal symptoms and photosensitivity reactions, among others) of treatment with pirfenidone. It is important to investigate pirfenidone׳s most cost-effective usage, and the ideal time of treatment initiation, the condition in which treatment should be initiated, and duration of treatment.

Pharmacological management of IPF

Idiopathic pulmonary fibrosis (IPF) is a deadly disease with a median survival of approximately three years in historical cohorts. Despite increased knowledge of disease pathophysiology and selection of more targeted therapy, main clinical trials yielded negative results. However, two agents, pirfenidone and nintedanib, were recently shown to be effective in IPF and received marketing authorization worldwide. Both drugs significantly reduce functional decline and disease progression with an acceptable safety profile. Yet, none of these drugs actually improves or even stabilizes the disease or the symptoms perceived by the patient. Several other treatments and combinations are currently tested, and many more are ready for clinical trials. Their completion is critical for achieving the ultimate goal of curing patients with IPF.

Marked Improvement with Pirfenidone in a Patient with Idiopathic Pulmonary Fibrosis

A man in his mid-60's with idiopathic pulmonary fibrosis and hepatitis B-related liver cirrhosis developed exertional dyspnea and a dry cough lasting for three months. High-resolution computed tomography (HRCT) showed increasing bilateral ground-glass opacity superimposed on the usual interstitial pneumonia pattern. Six months after starting pirfenidone therapy, the partial pressure of arterial oxygen at rest increased from 81 to 101 torr, the predicted forced vital capacity (FVC) value increased from 75% to 94% and the ground-glass opacity on HRCT improved. The FVC value was subsequently maintained near or above baseline for 43 months. We concluded that our patient was a super-responder to pirfenidone therapy.

Survival from an Acute Exacerbation of Idiopathic Pulmonary Fibrosis with or without Direct Hemoperfusion with a Polymyxin B-immobilized Fiber Column: A Retrospective Analysis

Objective Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) are fatal episodes of acute respiratory worsening of unknown etiology. Previous studies on acute respiratory distress syndrome have shown that direct hemoperfusion with a polymyxin B-immobilized fiber column (PMX-DHP) can have a beneficial effect on the respiratory status. This retrospective study investigated the prognosis and survival outcome of patients with AE-IPF who underwent PMX-DHP. Methods We examined the records of 50 patients with AE-IPF treated in our hospital. All patients received corticosteroid pulse therapy. We compared the disease outcome between 27 patients who underwent PMX-DHP (PMX group) and 23 patients who did not (non-PMX group). The independent predictors of survival were determined using Cox proportional hazards analyses. Results A multivariate analysis of all patients revealed that PMX-DHP therapy was a significant predictor of survival (HR=0.442, 95% CI 0.223-0.873; p=0.019). The 12-month survival rate was significantly higher in the PMX group than in the non-PMX group (41.7% vs. 9.8%; p=0.040). According to a subanalysis of the PMX group, the time from AE-IPF onset to PMX-DHP was a significant predictor of survival (HR=1.080, 95% CI 1.001-1.166; p=0.049). Conclusion PMX-DHP improved the prognosis of AE-IPF. The time from AE-IPF onset to PMX-DHP may therefore be informative for predicting the patient outcome.