Idiopathic Pulmonary Fibrosis Registry China study (PORTRAY): protocol for a prospective, multicentre registry study

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease characterised by a fibrotic histological pattern found in usual interstitial pneumonia. Its causes, pathogenesis, clinical phenotype and molecular mechanisms are poorly defined. Large-scale, multicentre studies are warranted to better understand IPF as a disease in China, its associated risk factors, clinical characteristics, diagnosis, disease progression and treatment.

METHODS AND ANALYSIS

The Idiopathic Pulmonary Fibrosis Registry China Study (PORTRAY) is a prospective, multicentre registry study of patients with IPF in China. Eight hundred patients will be enrolled over a 36-month period and followed for at least 3 years to generate a comprehensive database on baseline characteristics and various follow-up parameters including patient-reported outcomes. Biological specimens will also be collected from patients to develop a library of blood, bronchoalveolar lavage fluid and lung biopsy samples, to support future research. As of 15 December 2019, 204 patients from 19 large medical centres with relatively high IPF diagnosis and treatment rates had been enrolled. Patient characteristics will be presented using descriptive statistics. The Kaplan-Meier method will be used for survival analyses. Repeated measures will be used to compare longitudinal changes in lung function, imaging and laboratory tests. Results following analysis have been projected to be available by July 2025.

ETHICS AND DISSEMINATION

The study protocol was reviewed and approved by the Institutional Review Board from all the study sites currently recruiting patients. Study results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03666234.

Prevalence and risk factors of small airway dysfunction, and association with smoking, in China: findings from a national cross-sectional study

BACKGROUND

Small airway dysfunction is a common but neglected respiratory abnormality. Little is known about its prevalence, risk factors, and prognostic factors in China or anywhere else in the world. We aimed to estimate the prevalence of small airway dysfunction using spirometry before and after bronchodilation, both overall and in specific population subgroups; assess its association with a range of lifestyle and environmental factors (particularly smoking); and estimate the burden of small airway dysfunction in China.

METHODS

From June, 2012, to May, 2015, the nationally representative China Pulmonary Health study invited 57 779 adults to participate using a multistage stratified sampling method from ten provinces (or equivalent), and 50 479 patients with valid lung function testing results were included in the analysis. We diagnosed small airway dysfunction on the basis of at least two of the following three indicators of lung function being less than 65% of predicted: maximal mid-expiratory flow, forced expiratory flow (FEF) 50%, and FEF 75%. Small airway dysfunction was further categorised into pre-small airway dysfunction (defined as having normal FEV1 and FEV1/forced vital capacity [FVC] ratio before bronchodilator inhalation), and post-small airway dysfunction (defined as having normal FEV1 and FEV1/FVC ratio both before and after bronchodilator inhalation). Logistic regression yielded adjusted odds ratios (ORs) for small airway dysfunction associated with smoking and other lifestyle and environmental factors. We further estimated the total number of cases of small airway dysfunction in China by applying present study findings to national census data.

FINDINGS

Overall the prevalence of small airway dysfunction was 43·5% (95% CI 40·7-46·3), pre-small airway dysfunction was 25·5% (23·6-27·5), and post-small airway dysfunction was 11·3% (10·3-12·5). After multifactor regression analysis, the risk of small airway dysfunction was significantly associated with age, gender, urbanisation, education level, cigarette smoking, passive smoking, biomass use, exposure to high particulate matter with a diameter less than 2·5 μm (PM2·5) concentrations, history of chronic cough during childhood, history of childhood pneumonia or bronchitis, parental history of respiratory diseases, and increase of body-mass index (BMI) by 5 kg/m2. The ORs for small airway dysfunction and pre-small airway dysfunction were similar, whereas larger effect sizes were generally seen for post-small airway dysfunction than for either small airway dysfunction or pre-small airway dysfunction. For post-small airway dysfunction, cigarette smoking, exposure to PM2·5, and increase of BMI by 5 kg/m2 were significantly associated with increased risk, among preventable risk factors. There was also a dose-response association between cigarette smoking and post-small airway dysfunction among men, but not among women. We estimate that, in 2015, 426 (95% CI 411-468) million adults had small airway dysfunction, 253 (238-278) million had pre-small airway dysfunction, and 111 (104-126) million had post-small airway dysfunction in China.

INTERPRETATION

In China, spirometry-defined small airway dysfunction is highly prevalent, with cigarette smoking being a major modifiable risk factor, along with PM2·5 exposure and increase of BMI by 5 kg/m2. Our findings emphasise the urgent need to develop and implement effective primary and secondary prevention strategies to reduce the burden of this condition in the general population.

FUNDING

Ministry of Science and Technology of China; National Natural Science Foundation of China; National Health Commission of China.

Targeting FSTL1 for Multiple Fibrotic and Systemic Autoimmune Diseases

Follistatin-like 1 (FSTL1) is a matricellular protein that is upregulated during development and disease, including idiopathic pulmonary fibrosis (IPF), keloid, and arthritis. The profibrotic and pro-inflammatory roles of FSTL1 have been intensively studied during the last several years, as well as in this report. We screened and identified epitope-specific monoclonal neutralizing antibodies (nAbs) to functionally block FSTL1. FSTL1 nAbs attenuated bleomycin-induced pulmonary and dermal fibrosis in vivo and transforming growth factor (TGF)-β1-induced dermal fibrosis ex vivo in human skin. In addition, FSTL1 nAbs significantly reduced existing lung fibrosis and skin fibrosis in experimental models. FSTL1 nAbs exerted their potent antifibrotic effects via reduced TGF-β1 responsiveness and subsequent myofibroblast activation and extracellular matrix production. We also observed that FSTL1 nAbs attenuated the severity of collagen-induced arthritis in mice, which was accompanied by reduced inflammatory responses in vitro. Our findings suggest that FSTL1 nAbs are a promising new therapeutic strategy for the treatment of multiple organ fibrosis and systemic autoimmune diseases.

[Clinical characteristics of patients with antisynthetase syndrome and interstitial pulmonary disease]

Objective: To provide reference for clinicians in diagnosis and treatment of antisynthetase syndrome with interstitial pulmonary disease (ASS-ILD) by analyzing the clinical features, imaging features and pulmonary function changes of ASS-ILD patients. Methods: A total of 92 patients with ASS-ILD diagnosed in the Respiratory Center of China-Japan Friendship Hospital from January 2015 to May 2018 were included, clinical manifestations, high-resolution computed tomography (HRCT), pulmonary function test, treatment and outcome were retrospectively analyzed. Results: The average age of the 92 patients was (58.6±12.2) years with a ratio of male to female 1∶1.79. The main types of anti-synthetase antibody were anti-Jo-1 antibody (37 cases, 40.2%) and anti EJ antibody (26 cases, 28.3%). The most common symptoms of ASS-ILD were cough (79 cases, 85.9%), shortness of breath (60 cases, 65.2%), expectoration (54 cases, 58.7%), fever (34 cases, 36.9%), and common signs were craftsman's hand (30 cases, 32.6%) and joint pain (23 cases, 25.0%). The most common imaging findings in HRCT were ground-glass opacities(68 cases, 73.9%), reticulations (45 cases, 48.9%), tractive bronchiectasis (40 cases, 43.5%) and consolidation (39 cases, 42.4%). The most common types of ILD were non-specific interstitial pneumonia (NSIP) (63 cases, 68.5%), followed by NSIP-organic pneumonia (OP) (12 cases, 13.0%). The main type of lung function impairment was mild restrictive ventilation dysfunction. There were no significant differences in clinical features, imaging findings and pulmonary function changes in different subtypes of ASS-ILD patients (all P>0.05). Corticosteroids was used in 78 (84.8%) of ASS-ILD patients, and 34 cases (37.0%) were given cyclophosphamide. A total of 91 patients (98.9%) were discharged with improvement and 1 anti-EJ positive patient died. Conclusions: ASS-ILD occurs frequently in middle-aged and old women. Respiratory symptoms, craftsman's hands and arthritis are the most common clinical manifestations. The most common imaging types of ILD are NSIP and NSIP-OP. Corticosteroids is commonly used for treatment.

[When COVID-19 encounters interstitial lung disease: challenges and management]

In December 2019, a new type of coronavirus pneumonia (COVID-19) emerged in Wuhan, Hubei, and spread rapidly to China. The lung injury and repair caused by COVID-19 has many similarities with the onset and progression of interstitial lung disease (ILD) . Therefore, it is difficult to distinguish between COVID-19 and some types of new-onset ILD or other causes leading to acute exacerbation of ILD. Clinicians need to comprehensively analyze the epidemic history, disease onset characteristics, clinical manifestations, image characteristics, serological andpathogenic microorganism test results to confirm diagnosis. Because of this, the article will discuss the issues related to the differential diagnosis and management of COVID-19 and ILD, and try to provide reasonable suggestions.

Clinical characteristics of COVID-19 in patients with preexisting ILD: A retrospective study in a single center in Wuhan, China

Since the outbreak of 2019 novel coronavirus (SARS‐CoV‐2) pneumonia, many patients with underlying disease, such as interstitial lung disease (ILD), were admitted to Tongji hospital in Wuhan, China. To date, no data have ever been reported to reflect the clinical features of Corona Virus Disease 2019 (COVID‐19) among these patients with preexisting ILD. We analyzed the incidence and severity of COVID‐19 patients with ILD among 3201 COVID‐19 inpatients, and compared two independent cohorts of COVID‐19 patients with pre‐existing ILD (n = 28) and non‐ILD COVID‐19 patients (n = 130). Among those 3201 COVID‐19 inpatients, 28 of whom were COVID‐19 with ILD (0.88%). Fever was the predominant symptom both in COVID‐19 with ILD (81.54%) and non‐ILD COVID‐19 patients (72.22%). However, COVID‐19 patients with ILD were more likely to have cough, sputum, fatigue, dyspnea, and diarrhea. A very significantly higher number of neutrophils, monocytes, interleukin (IL)‐8, IL‐10, IL‐1β, and D‐Dimer was characterized in COVID‐19 with ILD as compared to those of non‐ILD COVID‐19 patients. Furthermore, logistic regression models showed neutrophils counts, proinflammatory cytokines (tumor necrosis factor‐alpha, IL6, IL1β, IL2R), and coagulation dysfunction biomarkers (D‐Dimer, PT, Fbg) were significantly associated with the poor clinical outcomes of COVID‐19. ILD patients could be less vulnerable to SARS‐CoV‐2. However, ILD patients tend to severity condition after being infected with SARS‐CoV‐2. The prognosis of COVID‐19 patients with per‐existing ILD is significantly worse than that of non‐ILD patients. And more, aggravated inflammatory responses and coagulation dysfunction appear to be the critical mechanisms in the COVID‐19 patients with ILD.

ILD patients could be less vulnerable to SARS‐CoV‐2. However, ILD patients tend to severity condition after being infected with SARS‐CoV‐2.

The prognosis of COVID‐19 patients with per‐existing ILD is significantly worse than that of non‐ILD patients. And more, aggravated inflammatory responses and coagulation dysfunction appear to be the critical mechanisms in the COVID‐19 patients with ILD.

[Corrigendum] Kinase inhibitors fail to induce mesenchymal‑epithelial transition in fibroblasts from fibrotic lung tissue

Following the publication of the above article, an interested reader drew to the authors' attention that Figs. 3A and 5A contained the same image derived under a light microscope. Fig. 3A was intending to show the cell morphology of primary cultured human lung fibroblasts. In examining their source data, the authors have come to realize that, during the process of figure preparation, an incorrect image for Fig. 3A was selected, and the figure was compiled incorrectly. The corrected version of Fig. 3, containing the correct microscopic image for Fig. 3A, is shown opposite. Note that this error did not affect understanding of the morphology of human lung fibroblasts, either in terms of the results or the conclusions reported in this paper. The authors apologize to the Editor of International Journal of Molecular Medicine and to readership for any inconvenience caused. [the original article was published in International Journal of Molecular Medicine 32: 430-438, 2013; DOI: 10.3892/ijmm.2013.1415].

Possible association of idiopathic pulmonary hemosiderosis with rheumatoid arthritis: A case report

Idiopathic pulmonary hemosiderosis (IPH) is a rare interstitial lung disease, usually occurring in children or young adults. Although several studies reported on the coexistence of IPH and immune system diseases, the association between these conditions has not been well described. The present study reports on the case of a 21-year-old female patient who presented with bilateral lung abnormalities. The patient was admitted due to a 2-year history of progressive exertional dyspnea, as well as arthralgia and joint swelling in the recent 2 months. During the past 15 years, the patient had been diagnosed with anemia and received repeated blood transfusions. Serial chest CT scans indicated an interstitial pattern. On physical examination, the patient had pale skin with a hemoglobin level of 65 g/l and exhibited finger-clubbing. Arterial blood gas analysis revealed hypoxia. Anticyclic-citrullinated protein antibody and rheumatoid factor were highly positive. Pulmonary function tests revealed restrictive ventilation dysfunction and decreased diffusion capacity. Bronchoscopy and biopsy confirmed diffuse alveolar hemorrhage. Following assessment of the etiology, the diagnosis of IPH was made by exclusion. The patient's symptoms and laboratory findings combined also confirmed the diagnosis of rheumatoid arthritis (RA). After receiving corticosteroid treatment, the patient's condition improved, and she was discharged and followed up. Based on this patient and a review of the literature, the present study demonstrated for the first time that IPH may mediate the development of an RA pathology. Therefore, early diagnosis is important for the timely management of IPH, which may also delay or even prevent the development of immune system diseases, e.g. RA, in patients with IPH. Further attention should be paid to determine the association between IPH and immune system diseases in the clinical setting.

SARS-CoV-2 and viral sepsis: observations and hypotheses

Since the outbreak of coronavirus disease 2019 (COVID-19), clinicians have tried every effort to understand the disease, and a brief portrait of its clinical features have been identified. In clinical practice, we noticed that many severe or critically ill COVID-19 patients developed typical clinical manifestations of shock, including cold extremities and weak peripheral pulses, even in the absence of overt hypotension. Understanding the mechanism of viral sepsis in COVID-19 is warranted for exploring better clinical care for these patients. With evidence collected from autopsy studies on COVID-19 and basic science research on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and SARS-CoV, we have put forward several hypotheses about SARS-CoV-2 pathogenesis after multiple rounds of discussion among basic science researchers, pathologists, and clinicians working on COVID-19. We hypothesise that a process called viral sepsis is crucial to the disease mechanism of COVID-19. Although these ideas might be proven imperfect or even wrong later, we believe they can provide inputs and guide directions for basic research at this moment.

IL-25/IL-33/TSLP contributes to idiopathic pulmonary fibrosis: Do alveolar epithelial cells and (myo)fibroblasts matter?

IMPACT STATEMENT

We suggest a novel modality in terms of IL-25/IL-33/TSLP's pro-fibrotic role in IPF. First, IL-25/IL-33/TSLP fully activates (myo)fibroblasts in fibroblastic foci (FF) in a paracrine-dependent manner. (IL-25/IL-33/TSLP)⁺alveolar epithelial cells-(IL-25R/IL-33R/TSLPR)⁺ (myo)fibroblasts axis may contribute greatly to the abnormal epithelial-mesenchymal crosstalk and lung fibrosis. Second, IL-25/IL-33/TSLP causes significant injury and phenotypic changes of alveolar epithelial cells in an autocrine-dependent manner. By acting directly on the two most important cells in the fibrotic process, i.e. alveolar epithelial cells and (myo)fibroblasts, we support the notion that biological therapies targeting IL-25/IL-33/TSLP will shed new light on the cure of IPF patients.

Metformin ameliorates bleomycin-induced pulmonary fibrosis in mice by suppressing IGF-1

Idiopathic pulmonary fibrosis (IPF) is a devastating disease, which is characterized by the progressive deterioration in lung function. In the pathogenesis of IPF, insulin-like growth factor-1 (IGF-1) has been found to be heavily involved. Metformin, a commonly used oral antidiabetic agent, is known to inhibit IGF-1 by the reversal of hyperinsulinemia. In this study, we evaluated the effects of metformin in pulmonary fibrosis in C57/BL6J mice, and further understand the role of IGF-1 signaling pathway involving in this process. Pulmonary fibrosis was induced experimentally in these mice by the intratracheal injection of bleomycin (BLM). Metformin was given orally the day before or 14 days after bleomycin injection, while pirfenidone was used as the positive control. Our study showed that intratracheal injection of bleomycin induced pulmonary fibrosis in mice, with observed elevation in collagen, fibronectin and α-SMA level, characterized by the enhanced IGF-1 and PI3K expression. Metformin was able to inhibit these effects significantly, and its antifibrotic effect had no marked difference with pirfenidone. Our results show that metformin attenuates bleomycin-induced pulmonary fibrosis via IGF-1 pathway.

An array of 60,000 antibodies for proteome-scale antibody generation and target discovery

Antibodies are essential for elucidating gene function. However, affordable technology for proteome-scale antibody generation does not exist. To address this, we developed Proteome Epitope Tag Antibody Library (PETAL) and its array. PETAL consists of 62,208 monoclonal antibodies (mAbs) against 15,199 peptides from diverse proteomes. PETAL harbors binders for a great multitude of proteins in nature due to antibody multispecificity, an intrinsic antibody feature. Distinctive combinations of 10,000 to 20,000 mAbs were found to target specific proteomes by array screening. Phenotype-specific mAb-protein pairs were found for maize and zebrafish samples. Immunofluorescence and flow cytometry mAbs for membrane proteins and chromatin immunoprecipitation-sequencing mAbs for transcription factors were identified from respective proteome-binding PETAL mAbs. Differential screening of cell surface proteomes of tumor and normal tissues identified internalizing tumor antigens for antibody-drug conjugates. By finding high-affinity mAbs at a fraction of current time and cost, PETAL enables proteome-scale antibody generation and target discovery.

The autocrine CXCR4/CXCL12 axis contributes to lung fibrosis through modulation of lung fibroblast activity

The C-X-C Motif Chemokine Receptor 4/C-X-C Motif Chemokine Ligand 12 (CXCR4/CXCL12) axis has been implicated in the pathogenesis of pulmonary fibrosis. However, the mechanisms governing this remain to be determined. The current study demonstrated that human lung fibroblasts (HLFs) exhibit high CXCL12 expression and also exhibit high expression of its corresponding receptor CXCR4. Exogenous CXCL12 was revealed to significantly promote the migration and proliferation of HLFs, and potentiate CXCR4 expression. These effects were demonstrated to be inhibited by AMD3100, which is an antagonist of CXCR4. Lung and bronchoalveolar lavage fluid CXCR4 and CXCL12 expression was upregulated by in vivo bleomycin administration, which was partially inhibited by pre-treatment with AMD3100. AMD3100 also reduced lung collagen content in the bleomycin model. Inhibiting CXCR4 was indicated to ameliorate the lung compliance and resistance of pulmonary fibrosis. In conclusion, the results of the present study suggested that autocrine CXCR4/CXCL12 axis is an important mechanism underlying the pathogenesis of idiopathic pulmonary fibrosis, and may serve as a potential therapeutic target that can be used in the treatment of pulmonary disease.

Misinterpretation of allergic bronchopulmonary aspergillosis/allergic bronchopulmonary mycosis due to diverse characteristics in different clinical stages

Background

Allergic bronchopulmonary mycosis (ABPM) is a complex pulmonary disorder caused by a hyperimmune response to the endobronchial growth of certain fungi. This study aims to aid physicians in better understanding the need for earlier recognition of ABPM.

Methods

Patients with a confirmed diagnosis of ABPM after evaluation were analyzed retrospectively. Clinical features, previous diagnoses and potential diagnostic errors, laboratory findings were reviewed and compiled.

Results

Fifty-seven patients were diagnosed with ABPM in which 22 were misdiagnosed. Eosinophilia was observed in 11 patients and an elevated total serum Ig E level greater than 1,000 kU/L was detected in 25 of the 57 patients. All of the patients were tested for specific Ig E in which positive to different fungi. The two most common abnormalities found on chest high-resolution computed tomography (HRCT) exams were central bronchiectasis and mucus plugs. A mild to moderate obstructive pattern of lung function was observed in 32 cases. By bronchofiberscopic observation, bronchial lumen was seen to have significant inflammation in 12 patients. After 3 weeks of treatment, a decreased serum total Ig E value was observed.

Conclusions

This study highlights the importance of increasing awareness and understanding of non-Aspergillus-ABPM among physicians and draws attention to the need for establishing more elaborate diagnostic criteria for non-Aspergillus-ABPM, which is a rare kind of disease.

Hydrogen inhalation attenuated bleomycin-induced pulmonary fibrosis by inhibiting transforming growth factor-β1 and relevant oxidative stress and epithelial-to-mesenchymal transition

NEW FINDINGS

• What is the central question of this study? The aim was to explore the effects and underlying mechanisms of H₂ on bleomycin-induced pulmonary fibrosis. • What are the main findings and its importance? Our results indicate that, in bleomycin-induced pulmonary fibrosis, H₂ inhalation attenuated oxidative stress and reversed the pulmonary epithelial-to-mesenchymal transition process by reducing reactive oxygen species production and inhibiting the expression of transforming growth factor-β1, α-smooth muscle actin and collagen I to improve fibrotic injury and exert anti-fibrogenic effects. Thus, H₂ inhalation has promising therapeutic potential as a useful adjuvant treatment for patients with idiopathic pulmonary fibrosis, which deserves further study and evaluation.

ABSTRACT

Hydrogen (H₂ ) can protect against tissue damage. The effect of H₂ inhalation therapy on the pathogenesis of pulmonary fibrosis remains unknown. This study was designed to explore the effects and underlying mechanisms of H₂ inhalation on bleomycin (BLM)-induced pulmonary fibrosis. A rat model of pulmonary fibrosis was established with BLM. Rats were randomly divided into control and H₂ inhalation groups. Haematoxylin and Eosin staining and Mason's Trichrome staining were performed to evaluate pulmonary fibrosis injury, inflammatory cell infiltration, structural disorder and collagen deposition. qRT-PCR and western blot assays were used to determine the expression of TNF-α, TGF-β1, α-SMA, E-cadherin, N-cadherin, vimentin, VEGF and collagen type I at both mRNA and protein levels. The contents of reactive oxygen species, TGF-β1, TNF-α, malondialdehyde and hydroxyproline were determined with biochemical test kits or ELISA kits. Bleomycin-stimulated rats exhibited typical symptoms of pulmonary fibrosis, which featured an increase in collagen deposition, alveolitis, fibrosis and parenchymal structural disorder in the lung. However, BLM-induced oxidative stress was attenuated by H₂ inhalation therapy, which reduced the contents of reactive oxygen species, malondialdehyde and hydroxyproline, enhanced the activity of glutathione peroxidase and decreased the expression of TGF-β1 and TNF-α. In addition, H₂ inhalation also inhibited BLM-induced epithelial-to-mesenchymal transition by inhibiting TGF-β1, increasing the expression level of the epithelial cell marker E-cadherin, and decreasing the expression level of the mesenchymal cell marker vimentin in a time-dependent manner. In addition, H₂ inhalation downregulated α-SMA expression and suppressed collagen I generation, exerting anti-fibrogenic effects. Hydrogen inhalation therapy attenuates BLM-induced pulmonary fibrosis by inhibiting TGF-β1, relevant oxidative stress and epithelial-to-mesenchymal transition.

[Differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia]

Objective: To investigate the differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia (IIPs). Methods: A total of 46 patients with IIPs confirmed by video assisted thoracoscopic or open lung biopsy, hospitalized in the Respiratory and Critical Care Medicine of Beijing Chao-Yang Hospital, from Dec. 1998 through Nov. 2007 were studied, including 19 patients with idiopathic pulmonary fibrosis (IPF group), 14 with nonspecific interstitial pneumonia (NSIP group), and 13 cryptogenic organizing pneumonia (COP group). Pulmonary function and high resolution CT (HRCT) of the patients were examined before lung biopsy, and lung biopsy tissue were stained with hematoxylin-eosin. The abnormality of small airways in pathology, pulmonary function and HRCT were compared among these patients with IIPs. Results: Small airway inflammatory cell infiltration score (53.8±17.7) was significantly higher in the COP group than in the IPF group (38.8±9.7) (P<0.01). The fibrous tissue proliferation score in small airways (42.9±12.1) in the IPF group was significantly higher than that in the NSIP group (31.4±10.5) and the COP group (26.7±16.3) (both P<0.05). In the IPF group, NSIP group and COP group, the small airway function index was significantly reduced, and the maximum expiratory flow rate (V(25%), V(50%)) at 25% and 50% of the lung capacity was<80% predicted, the incidences of small airway dysfunction in the three groups were 63.2%, 69.2%, and 63.6%, respectively. There was no significant difference among the groups (P>0.05). Small airway inflammatory cell infiltration was negatively correlated with V(50%) of small airway function (r=-0.305, P=0.049). The bronchodilation rate in the HRCT of the IPF group (100%) was significantly higher than that of the NSIP group (50.0%) and the COP group (53.8%) (both P<0.01). Conclusion: The patients with IPF, NSIP and COP have abnormal pathologic, physiological and imaging changes of small airways, moreover have different characteristics.

Prevalence, risk factors, and management of asthma in China: a national cross-sectional study

BACKGROUND

Asthma is a common chronic airway disease worldwide. Despite its large population size, China has had no comprehensive study of the national prevalence, risk factors, and management of asthma. We therefore aimed to estimate the national prevalence of asthma in a representative sample of the Chinese population.

METHODS

A representative sample of 57 779 adults aged 20 years or older was recruited for the national cross-sectional China Pulmonary Health (CPH) study using a multi-stage stratified sampling method with parameters derived from the 2010 census. Ten Chinese provinces, representative of all socioeconomic settings, from six geographical regions were selected, and all assessments were done in local health centres. Exclusion criteria were temporary residence, inability to take a spirometry test, hospital treatment of cardiovascular conditions or tuberculosis, and pregnancy and breastfeeding. Asthma was determined on the basis of a self-reported history of diagnosis by a physician or by wheezing symptoms in the preceding 12 months. All participants were assessed with a standard asthma questionnaire and were classed as having or not having airflow limitation through pulmonary function tests before and after the use of a bronchodilator (400 μg of salbutamol). Risk factors for asthma were examined by multivariable-adjusted analyses done in all participants for whom data on the variables of interest were available. Disease management was assessed by the self-reported history of physician diagnosis, treatments, and hospital visits in people with asthma.

FINDINGS

Between June 22, 2012, and May 25, 2015, 57 779 participants were recruited into the CPH study. 50 991 (21 446 men and 29 545 women) completed the questionnaire survey and had reliable post-bronchodilator pulmonary function test results and were thus included in the final analysis. The overall prevalence of asthma in our sample was 4·2% (95% CI 3·1-5·6), representing 45·7 million Chinese adults. The prevalence of asthma with airflow limitation was 1·1% (0·9-1·4), representing 13·1 million adults. Cigarette smoking (odds ratio [OR] 1·89, 95% CI 1·26-2·84; p=0·004), allergic rhinitis (3·06, 2·26-4·15; p<0·0001), childhood pneumonia or bronchitis (2·43, 1·44-4·10; p=0·002), parental history of respiratory disease (1·44, 1·02-2·04; p=0·040), and low education attainment (p=0·045) were associated with prevalent asthma. In 2032 people with asthma, only 28·8% (95% CI 19·7-40·0) reported ever being diagnosed by a physician, 23·4% (13·9-36·6) had a previous pulmonary function test, and 5·6% (3·1-9·9) had been treated with inhaled corticosteroids. Furthermore, 15·5% (11·4-20·8) people with asthma reported at least one emergency room visit and 7·2% (4·9-10·5) at least one hospital admission due to exacerbation of respiratory symptoms within the preceding year.

INTERPRETATION

Asthma is prevalent but largely undiagnosed and undertreated in China. It is crucial to increase the awareness of asthma and disseminate standardised treatment in clinical settings to reduce the disease burden.

FUNDING

National Key R&D Program of China, Ministry of Science and Technology of China; the Special Research Foundation for Public Welfare of Health, Ministry of Health of China; the Chinese National Research Program for Key Issues in Air Pollution Control; and the National Natural Science Foundation of China.

Single-cell RNA sequencing profiling of the effects of aging on alveolar stem cells

The aging of alveolar stem cells has been linked to many chronic lung diseases, including pulmonary fibrosis. However, the effects of aging on alveolar stem cells during homeostasis and post-injury alveolar repair have not been well characterized. Here we conducted a single-cell RNA sequencing (scRNA-seq) analysis of alveolar stem cells of 3-month-old and 12-month-old mice to characterize the aging effect on alveolar stem cells. Our results have shown that the transcriptomes of alveolar stem cells of 3-month-old and 12-month-old mice are not significantly different under the steady condition. However, after a bleomycin-induced lung injury, the alveolar stem cells of 12-month-old mice show enhanced inflammatory responses and decreased lipid metabolism. Our study suggests a close relationship among aging, lipid metabolism, inflammatory responses and chronic lung diseases.

Serum prealbumin is a prognostic indicator in idiopathic pulmonary fibrosis

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease characterized by variable progression. The prealbumin (PA) is a parameter in a routine blood biochemistry examination. We sought to investigate the prognostic value in IPF patients.

OBJECTIVES

To evaluate the prognosis value in patients with IPF.

METHODS

Blood biochemistry examination, demographics, pulmonary function data from patients with IPF consulted in Beijing Chao-Yang Hospital and China-Japan Friendship Hospital between July 2012 and December 2016 were collected. Infection, liver and kidney dysfunction and lung transplantation are excluded from the cohort.

RESULTS

The result of multivariate Cox analysis showed that PA was significant prognostic indicator of survival along with BMI, FVC, serum albumin protein and serum global protein. The patients with PA concentration <0.2 mg/L had shorter survival compared with those whose PA were normal. Although the survival had no significant difference between the patients with PA concentration < 0.2 mg/L and albumin < 35 g/L and those with PA concentration < 0.2 mg/L, the average survival time of patients with PA concentration < 0.2 mg/L and albumin < 35 g/L were shorter.

CONCLUSIONS

Our study indicated that IPF patients with PA concentration < 0.2 mg/L have poorer outcome. Further studies are warranted to indentify PA as a predictor for IPF patients outcomes and explore the role of PA in the pathogenesis of IPF.

Independent Clinical Factors Relevant to Prognosis of Patients with Idiopathic Pulmonary Fibrosis

Background

The prognosis of idiopathic pulmonary fibrosis (IPF) is the worst among all interstitial lung diseases, and is related to the disease itself. Comorbidities or complications can worsen IPF. We assessed the effect of comorbidities on the survival of IPF patients. A retrospective review of patients with IPF was completed.

Material/Methods

Information on demographic features, clinical examination, and comorbidities at baseline were obtained. Then, median, 1-year, and 5-year survival was calculated. A total of 380 patients with IPF admitted to Beijing Chao-Yang Hospital from 1 April 2002 to 31 March 2015 were followed up until December 2016.

Results

Of these 380 patients, 71.9% died during the study period. Median survival was 2.25 years and overall 5-year survival was 28.5%. Also, 86.3% of patients were males. A total of 248 cases underwent lung function tests, and 178 patients underwent bronchoalveolar lavage (BAL). Multivariate analyses showed that forced expiratory volume in 1 second/forced vital capacity (FVC), diffusing capacity of the lungs for carbon monoxide percent predicted, FVC% predicted, the number of macrophages, neutrophils, and lymphocytes in BAL fluid, pulmonary hypertension, hypoxemia, and hydropower disorder were independent prognostic indicators of IPF, GAP gender (G), age (A), and 2 pulmonary physiological parameters (P) model can help to predict prognosis of IPF.

Conclusions

Spirometry, GAP model, and BAL are helpful to forecast the prognosis of IPF. IPF patients also suffering from pulmonary arterial hypertension, hypoxemia, and hydropower disorder have a poor prognosis.