Idiopathic pulmonary fibrosis: early detection and referral

Lung Ultrasound Spectroscopy Applied to the Differential Diagnosis of Pulmonary Diseases: An In Vivo Multicenter Clinical Study

Lung ultrasound (LUS) is an important imaging modality to assess the state of the lung surface. However, current LUS approaches are based on subjective interpretation of imaging artifacts, which results in poor specificity as quantitative evaluation lacks. The latter could be improved by adopting LUS spectroscopy of vertical artifacts. Indeed, parameterizing these artifacts with native frequency, bandwidth, and total intensity ( [Formula: see text]) already showed potentials in differentiating pulmonary fibrosis (PF). In this study, we acquired radio frequency (RF) data from 114 patients. These data (representing the largest LUS RF dataset worldwide) were acquired by utilizing a multifrequency approach, implemented with an ULtrasound Advanced Open Platform (ULA-OP). Convex (CA631) and linear (LA533) probes (Esaote, Florence, Italy) were utilized to acquire RF data at three (2, 3, and 4 MHz), and four (3, 4, 5, and 6 MHz) imaging frequencies. A multifrequency analysis was conducted on vertical artifacts detected in patients having cardiogenic pulmonary edema (CPE), pneumonia, or PF. These artifacts were characterized by the three abovementioned parameters, and their mean values were used to project each patient into a feature space having up to three dimensions. Binary classifiers were used to evaluate the performance of these three mean features in differentiating patients affected by CPE, pneumonia, and PF. Acquisitions of multifrequency data performed with linear probe lead to accuracies up to 85.43% in the differential diagnosis of these diseases (convex probes' maximum accuracy was 74.51%). Moreover, the results showed high potentials of mean [Formula: see text] (by itself or combined with other features) in improving LUS specificity.

Quantitative CT analysis of idiopathic pulmonary fibrosis and correlation with lung function study

BACKGROUND

Idiopathic Pulmonary Fibrosis (IPF) is a progressive fibrotic lung disease. However, the field of quantitative CT scan analysis in conjunction with pulmonary function test for IPF patients remains relatively understudied. In this study, we evaluated the diagnostic value of features derived high-resolution computed tomography (HRCT) for patients with IPF and correlated them with pulmonary function tests.

METHODS

We retrospectively analyzed the chest HRCT images and pulmonary function test results of 52 patients with IPF during the same period (1 week) and selected 52 healthy individuals, matched for sex, age, and body mass index (BMI) and with normal chest HRCT as controls. HRCT scans were performed using a Philips 256-row Brilliance iCT scanner with standardized parameters. Lung function tests were performed using a Jaeger volumetric tracer for forced vital capacity (FVC), total lung capacity (TLC), forced expiratory volume in first second (FEV1), FEV1/FVC, carbon monoxide diffusing capacity (DLCO), and maximum ventilation volume (MVV) metrics. CT quantitative analysis, including tissue segmentation and threshold-based quantification of lung abnormalities, was performed using 3D-Slicer software to calculate the percentage of normal lung areas (NL%), percentage of ground-glass opacity areas (GGO%), percentage of fibrotic area (F%) and abnormal lesion area percentage (AA%). Semi-quantitative analyses were performed by two experienced radiologists to assess disease progression. The aortic-to-sternal distance (ASD) was measured on axial images as a standardized parameter. Spearman or Pearson correlation analysis and multivariate stepwise linear regression were used to analyze the relationship between the data in each group, and the ROC curve was used to determine the optimal quantitative CT metrics for identifying IPF and controls.

RESULTS

ROC curve analysis showed that F% distinguished the IPF patient group from the control group with the largest area under the curve (AUC) of 0.962 (95% confidence interval: 0.85-0.96). Additionally, with F% = 4.05% as the threshold, the Youden's J statistic was 0.827, with a sensitivity of 92.3% and a specificity of 90.4%. The ASD was significantly lower in the late stage of progression than in the early stage (t = 5.691, P < 0.001), with a mean reduction of 2.45% per month. Quantitative CT indices correlated with all pulmonary function parameters except FEV1/FVC, with the highest correlation coefficients observed for F% and TLC%, FEV1%, FVC%, MVV% (r = - 0.571, - 0.520, - 0.521, - 0.555, respectively, all P-values < 0.001), and GGO% was significantly correlated with DLCO% (r = - 0.600, P < 0.001). Multiple stepwise linear regression analysis showed that F% was the best predictor of TLC%, FEV1%, FVC%, and MVV% (R2 = 0.301, 0.301, 0.300, and 0.302, respectively, all P-values < 0.001), and GGO% was the best predictor of DLCO% (R2 = 0.360, P < 0.001).

CONCLUSIONS

Quantitative CT analysis can be used to diagnose IPF and assess lung function impairment. A decrease in the ASD may indicate disease progression.

Referral rates and barriers to lung transplantation based on pulmonary function criteria in interstitial lung diseases: a retrospective cohort study

BACKGROUND

Interstitial lung diseases (ILD) unresponsive to medical therapy often require lung transplantation (LTx), which prolongs quality of life and survival. Ideal timing for referral for LTx remains challenging, with late referral associated with significant morbidity and mortality. Among other criteria, patients with ILD should be considered for LTx if forced vital capacity (FVC) is less than 80% or diffusion capacity for carbon monoxide (DLCO) is less than 40%. However, data on referral rates are lacking.

OBJECTIVES

To evaluate referral rates for LTx based on pulmonary function tests (PFTs) and identify barriers associated with non-referral.

DESIGN

A single-center retrospective cohort study.

METHODS

The study consisted of ILD patients who performed PFT between 2014 and 2020. Patients with FVC < 80% or a DLCO < 40% were included in the study. Patients with absolute contraindications to LTx were excluded. Referral rates were computed, and a comparison was made between referred and non-referred subjects.

RESULTS

Out of 114 ILD patients meeting criteria for referral to LTx, 35 were referred (30.7%), and 7 proceeded to undergo LTx. Median time from PFT to referral for assessment was 255 days [interquartile range (IQR) 35-1077]. Median time from referral to LTx was 89 days (IQR 59-143). Referred patients were younger (p = 0.003), had lower FVC (p < 0.001), DLCO (p < 0.001), and a higher rate of pulmonary hypertension (p = 0.04). Relatively better PFT, and older age, were significantly associated with non-referral of patients.

CONCLUSION

There is under-referral of ILD patients who are eligible for LTx, which is associated with severe disease and missed opportunities for LTx. Further research is required to validate these findings.

Speaking of the "Devil": Diagnostic Errors in Interstitial Lung Diseases

Interstitial lung diseases are respiratory diseases, which affect the normal lung parenchyma and can lead to significant pulmonary fibrosis, chronic respiratory failure, pulmonary hypertension, and ultimately death. Reuniting more than 200 entities, interstitial lung diseases pose a significant challenge to the clinician, as they represent rare diseases with vague and insidious respiratory symptoms. As such, there are many diagnostic errors that can appear along the journey of the patient with ILD, which leads to significant delays with implications for the prognosis and the quality of life of the patient.

Screening for idiopathic pulmonary fibrosis using comorbidity signatures in electronic health records

Idiopathic pulmonary fibrosis (IPF) is a lethal fibrosing interstitial lung disease with a mean survival time of less than 5 years. Nonspecific presentation, a lack of effective early screening tools, unclear pathobiology of early-stage IPF and the need for invasive and expensive procedures for diagnostic confirmation hinder early diagnosis. In this study, we introduce a new screening tool for IPF in primary care settings that requires no new laboratory tests and does not require recognition of early symptoms. Using subtle comorbidity signatures identified from the history of medical encounters of individuals, we developed an algorithm, called the zero-burden comorbidity risk score for IPF (ZCoR-IPF), to predict the future risk of an IPF diagnosis. ZCoR-IPF was trained on a national insurance claims database and validated on three independent databases, comprising a total of 2,983,215 participants, with 54,247 positive cases. The algorithm achieved positive likelihood ratios greater than 30 at a specificity of 0.99 across different cohorts, for both sexes, and for participants with different risk states and history of confounding diseases. The area under the receiver-operating characteristic curve for ZCoR-IPF in predicting IPF exceeded 0.88 and was approximately 0.84 at 1 and 4 years before a conventional diagnosis, respectively. Thus, if adopted, ZCoR-IPF can potentially enable earlier diagnosis of IPF and improve outcomes of disease-modifying therapies and other interventions.

Potential interstitial lung abnormalities on chest X-rays prior to symptoms of idiopathic pulmonary fibrosis

Background

Idiopathic pulmonary fibrosis (IPF) often has significant diagnostic delay. At present it is not well-known what factors associate with time to diagnosis and if this is associated with survival after the diagnosis. There has also been increasing attention for interstitial lung abnormalities on chest CT-scans. In this study we assessed what factors associate with time to diagnosis in patients with IPF, and whether early stages of pulmonary fibrosis can be seen on chest X-rays prior to the start of symptoms.

Methods

In this retrospective study, 409 Dutch patients with IPF were included. Clinical characteristics, including patient demographics, medical history, time of start of symptoms, time of first visit to pulmonologist, and any previous radiographic imaging reports were collected from patient records.

Results

In 96 patients (23%) a chest X-ray was available that had been made prior to the start of symptoms (median of 50.5 months (IQR 26.3–83.3 months)), and this showed potential interstitial lung abnormalities in 56 patients (58%). The median time from the start of symptoms to the final diagnosis was 24.0 months (interquartile range 9.0–48.0 months). In a multivariate model that corrected for diffusion capacity of the lung for carbon monoxide, forced vital capacity, sex, and age at diagnosis, time to diagnosis did not associate with survival (hazard ratio 1.051 (95% CI 0.800–1.380; p = 0.72)).

Conclusions

There is a significant diagnostic delay for patients with IPF, but longer time to diagnosis did not associate with survival. Interstitial lung abnormalities were seen in more than half of the patients in whom a chest X-ray had been made prior to the start of symptoms. This illustrates that a computed tomography scan should be strongly considered for analysis of unexplained abnormalities on a chest X-ray. This could facilitate early detection and possibly prevention of disease progression for patients with pulmonary fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02122-8.

Diagnostic delay in IPF impacts progression-free survival, quality of life and hospitalisation rates

BACKGROUND

The diagnosis of idiopathic pulmonary fibrosis (IPF) is often delayed up to several years. The objective of this study was to assess the impact of the diagnostic delay on progression-free survival, quality of life and hospitalisation rates.

METHODS

A total of 264 incident patients with IPF were included immediately after their diagnosis and followed for up to 5 years, with regular collection of clinical data, quality-of-life questionnaires and assessment of disease progression. Hospitalisation data were extracted from electronic patient records. Analyses were performed on the entire cohort and strata according to forced vital capacity (FVC) at diagnosis.

RESULTS

A long diagnostic delay (>1 year) was associated with worse progression-free survival compared with a short diagnostic delay (<1 year) (HR: 1.70, 95% CI: 1.18 to 2.46, p=0.004) especially in patients with mild disease at the time of diagnosis (FVC>80% predicted). Mean total scores of the St. George's respiratory questionnaire (SGRQ), a derived IPF-specific version of the SGRQ and the chronic obstructive pulmonary disease assessment test (CAT) were consistently higher in patients with long diagnostic delays, indicating worse quality of life. Mean hospitalisation rates were higher during the first year after diagnosis (Incidence rate ratio [IRR]: 3.28, 95% CI: 1.35 to 8.55, p=0.01) and during the entire follow-up (IRR: 1.74, 95% CI: 1.01 to 3.02, p=0.04).

CONCLUSION

A diagnostic delay of more than 1 year negatively impacts progression-free survival, quality of life and hospitalisation rates in patients with IPF. These findings highlight the importance of an early diagnosis for proper management of IPF.

TRIAL REGISTRATION NUMBER

NCT02755441.

A retrospective study on the efficacy of Ninjin'yoeito on fatigue in patients with interstitial pneumonia

INTRODUCTION

Fatigue, caused by dyspnea associated with progression of interstitial pneumonia (IP), can negatively affect patients' quality of life (QOL). Ninjin'yoeito (NYT), a Chinese herbal medicine, is prescribed for general symptoms of fatigue and for fatigue associated with various respiratory diseases. However, there is a lack of integrated research on the effects of NYT in patients with IP. Therefore, we retrospectively investigated the efficacy of NYT in patients with IP and fatigue.

MATERIALS AND METHODS

From the IP patients who had taken NYT, 19 who met the following inclusion criteria were included: (1) age of ≥20 years, (2) fatigue, and (3) history of NYT administration. The primary endpoint was fatigue, which was assessed using the Chalder Fatigue Scale (CFS). The secondary endpoints were loss of appetite and dyspnea, which were evaluated using the Simplified Nutritional Appetite Questionnaire (SNAQ) and modified Medical Research Council (mMRC) scores, respectively. All items were measured before and after 12 weeks of NYT administration.

RESULTS

In the enrolled 19 patients (male, 12; female, 7; mean age, 65.8 ± 12.7 years), the underlying diseases were idiopathic pulmonary fibrosis (n = 8), idiopathic pleuroparenchymal fibroelastosis (n = 5), connective tissue disease-related interstitial pneumonia (n = 2), chronic hypersensitivity pneumonitis (n = 3), and nonspecific interstitial pneumonia (n = 1). The CFS score decreased from 17.1 ± 6.8 before administration to 13.4 ± 5.7 after administration of NYT (p = 0.0389). The SNAQ score did not change markedly. The median mMRC score decreased from 3 to 2, however, the difference was not significant.

CONCLUSION

Many subtypes of IP are progressive, and a cure cannot be expected in cases of irreversible lung fibrosis. Therefore, a multifaceted approach to improve and maintain the QOL is needed in addition to the standard of care. This study showed that NYT can improve fatigue and help maintain the QOL in IP patients.

Diagnostic Classification of Interstitial Lung Disease in Clinical Practice

Interstitial lung diseases (ILDs) are challenging to diagnose, requiring integration of multiple complex features that are often difficult to interpret. This article reviews a pragmatic approach to ILD diagnosis and classification, focusing on diagnostic tools and strategies that are used to separate different subtypes and identify the most appropriate management. We discuss the evolution of ILD classification and the contemporary approach that integrates routinely used diagnostic tools in a multidisciplinary discussion. We highlight the increasing importance of taking a multipronged approach to ILD classification that reflects the recent emphasis on disease behavior while also considering etiopathogenesis and morphologic features.

Effects of Exercise Training on Cardiopulmonary Function and Quality of Life in Elderly Patients with Pulmonary Fibrosis: A Meta-Analysis

(1) Objective: Our objective was to conduct a meta-analysis of randomized controlled trials that have evaluated the benefits of exercise training for elderly pulmonary fibrosis (PF) patients. (2) Methods: Studies in either English or Chinese were retrieved from the China National Knowledge Infrastructure (CNKI) and the Wanfang, PubMed, Web of Science and SPORTDiscus databases from inception until the first week of April 2021. Age, body mass index (BMI), and exercise frequency, intensity, type, and duration were considered for each participant. The specific data recorded were the six-minute walk distance (6MWD), maximal rate of oxygen consumption (peak VO2), predicted forced vital capacity (FVC% pred), predicted diffusing capacity of the lung for carbon monoxide (DLCO% pred), predicted total lung capacity (TLC% pred), St. George's respiratory questionnaire (SGRQ) total score and a modified medical research council score (mMRC). (3) Results: Thirteen studies comprised this meta-analysis (eleven randomized controlled trials and two prospective studies design), wherein 335 patients were exercised and 334 were controls. The results showed that exercise training increased the 6MWD (Cohen's d = 0.77, MD = 34.04 (95% CI, 26.50-41.58), p < 0.01), peak VO2 (Cohen's d = 0.45, MD = 1.13 (95% CI, 0.45-1.82), p = 0.0001) and FVC% pred (Cohen's d = 0.42, MD = 3.94 (95% CI, 0.91-6.96), p = 0.01). However, exercise training reduced scores for the SGRQ (Cohen's d = 0.89, MD = -8.79 (95% CI, -10.37 to -7.21), p < 0.01) and the mMRC (Cohen's d = 0.64, MD = -0.58 (95% CI, -0.79 to -0.36), p < 0.01). In contrast, exercise training could not increase DLCO% pred (Cohen's d = 0.16, MD = 1.86 (95% CI, -0.37-4.09), p = 0.10) and TLC% pred (Cohen's d = 0.02, MD = 0.07 (95% CI, -6.53-6.67), p = 0.98). Subgroup analysis showed significant differences in frequency, intensity, type, and age in the 6MWD results (p < 0.05), which were higher with low frequency, moderate intensity, aerobic-resistance-flexibility-breathing exercises and age ≤ 70. Meanwhile, the subgroup analysis showed significant differences in exercise intensity and types in the mMRC results (p < 0.05), which were lower with moderate intensity and aerobic-resistance exercises. (4) Conclusions: Exercise training during pulmonary rehabilitation can improved cardiopulmonary endurance and quality of life in elderly patients with PF. The 6MWDs were more noticeable with moderate exercise intensity, combined aerobic-resistance-flexibility-breathing exercises and in younger patients, which all were not affected by BMI levels or exercise durations. As to pulmonary function, exercise training can improve FVC% pred, but has no effect on DLCO% pred and TLC% pred.

Outcomes of Idiopathic Pulmonary Fibrosis Improve with Obesity: A Rural Appalachian Experience

OBJECTIVES

Obesity can be an independent predictor of fibrosis in tissues, including the liver, heart, and skin. We evaluated a rural Appalachian cohort of idiopathic pulmonary fibrosis (IPF) for its relation to obesity.

METHODS

Using American Thoracic Society 2018 diagnostic guidelines, an IPF cohort was systematically identified at an Appalachian academic medical center (2015-2019). The cohort was categorized in subgroups of body mass index (BMI) <30 or BMI ≥30 kg/m². Demographics, clinical variables, and treatment details were collected retrospectively and evaluated for their associations with obesity.

RESULTS

In our IPF cohort (N = 138), a usual interstitial pneumonia pattern was less prevalent in the obese group (n = 49) relative to the nonobese group (69% vs 85%, respectively). The obese group was younger (mean age 73.27 ± 9.12 vs 77.97 ± 9.59 years) and had a higher prevalence of hypertension (90% vs 72%), hyperlipidemia (83% vs 68%), diabetes mellitus (47% vs 25%), sleep-disordered breathing (47% vs 25%), chronic pain disorders (28% vs 15%), and deep vein thrombosis (19% vs 7%). An increased proportion of obese-IPF patients was seen at a tertiary or an interstitial lung disease center, with more surgical lung biopsies performed and incident diagnosis (ie, within 6 months of presentation) assigned. Only a minority of patients underwent lung transplantation (3.6%), all of them from the obese-IPF subgroup. Approximately 30% of the total IPF cohort died, with a lower mortality observed in the obese group (35% vs 20%, P = 0.017). An increasing BMI predicted a better survival in the total IPF cohort (BMI 25-29.9, 20-24.9, and <20 had mortality rates of 20%, 47%, and 75%, respectively; P < 0.001).

CONCLUSIONS

Our study represents a first known effort to develop an IPF cohort in a rural Appalachian region. Although they shared an increased burden of comorbidities, the obese subgroup showed less advanced fibrosis with a lower mortality rate relative to nonobese subgroup, suggesting a potential "obesity paradox" in IPF. The study findings significantly advance our understanding of challenges posed by IPF in a rural population that also suffers from an alarming rate of obesity. We highlight the need for the multidisciplinary management of these patients and prospective studies to better define this complex relation.

Diagnostic delay of associated interstitial lung disease increases mortality in rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease whose main extra-articular organ affected is the lung, sometimes in the form of diffuse interstitial lung disease (ILD) and conditions the prognosis. A multicenter, observational, descriptive and cross-sectional study of consecutive patients diagnosed with RA-ILD. Demographic, analytical, respiratory functional and evolution characteristics were analyzed to evaluate the predictors of progression and mortality. 106 patients were included. The multivariate analysis showed that the diagnostic delay was an independent predictor of mortality (HR 1.11, CI 1.01-1.23, p = 0.035). Also, age (HR 1.33, 95% CI 1.09-1.62, p = 0.0045), DLCO (%) (HR 0.85, 95% CI 0.73-0.98, p = 0.0246), and final SatO2 (%) in the 6MWT (HR 0.62, 95% CI 0.39-0.99, p = 0.0465) were independent predictor variables of mortality, as well as GAP index (HR 4.65, 95% CI 1.59-13.54, p = 0.0051) and CPI index (HR 1.12, 95% CI 1.03-1.22, p = 0.0092). The withdrawal of MTX or LFN after ILD diagnosis was associated with disease progression in the COX analysis (HR 2.18, 95% CI 1.14-4.18, p = 0.019). This is the first study that highlights the diagnostic delay in RA-ILD is associated with an increased mortality just like happens in IPF.

Quantitative Lung Ultrasound Spectroscopy Applied to the Diagnosis of Pulmonary Fibrosis: The First Clinical Study

The application of ultrasound imaging to the diagnosis of lung diseases is nowadays receiving growing interest. However, lung ultrasound (LUS) is mainly limited to the analysis of imaging artifacts, such as B-lines, which correlate with a wide variety of diseases. Therefore, the results of LUS investigations remain qualitative and subjective, and specificity is obviously suboptimal. Focusing on the development of a quantitative method dedicated to the lung, in this work, we present the first clinical results obtained with quantitative LUS spectroscopy when applied to the differentiation of pulmonary fibrosis. A previously developed specific multifrequency ultrasound imaging technique was utilized to acquire ultrasound images from 26 selected patients. The multifrequency imaging technique was implemented on the ULtrasound Advanced Open Platform (ULA-OP) platform and an LA533 (Esaote, Florence, Italy) linear-array probe was utilized. RF data obtained at different imaging frequencies (3, 4, 5, and 6 MHz) were acquired and processed in order to characterize B-lines based on their frequency content. In particular, B-line native frequencies (the frequency at which a B-line exhibits the highest intensity) and bandwidth (the range of frequencies over which a B-line shows intensities within -6 dB from its highest intensity), as well as B-line intensity, were analyzed. The results show how the analysis of these features allows (in this group of patients) the differentiation of fibrosis with a sensitivity and specificity equal to 92% and 92%, respectively. These promising results strongly motivate toward the extension of the clinical study, aiming at analyzing a larger cohort of patients and including a broader range of pathologies.

Aerobic and breathing exercises improve dyspnea, exercise capacity and quality of life in idiopathic pulmonary fibrosis patients: systematic review and meta-analysis

Background

Idiopathic pulmonary fibrosis (IPF) is a progressive disease associated with significant dyspnea and limited exercise capacity. This systematic review aimed to synthesize evidence of exercise interventions during pulmonary rehabilitation that aim to improve exercise capacity, dyspnea, and health-related quality of life (HRQL) in IPF patients.

Methods

Searches were performed in MEDLINE, Embase, CENTRAL, SPORTDiscus, PubMed and PEDro from inception to January 2019 using search terms for: (I) participants: ‘IPF or interstitial lung disease’; (II) interventions: ‘aerobic training or resistance training or respiratory muscle training’; and (III) outcomes: ‘exercise capacity or dyspnea or health-related quality of life’. Two reviewers independently screened titles, abstracts and full texts to identify eligible studies. Methodological quality of studies was assessed using the Downs and Black checklist and meta-analyses were performed.

Results

Of 1,677 articles identified, 14 were included (four randomized controlled trials and 10 prospective pre-post design studies) that examined 362 patients receiving training and 95 control subjects. Exercise capacity was measured with the 6-minute walk distance, peak oxygen consumption, peak work rate, or endurance time for constant work rate cycling, which increased after exercise [aerobic exercise; aerobic and breathing exercises; aerobic and inspiratory muscle training (IMT) exercises] compared to the control groups. Dyspnea scores improved after aerobic and breathing exercises. HRQL also improved after aerobic exercise training alone or combined with breathing exercises. Aerobic training alone or combined with IMT or breathing exercises improved exercise capacity.

Conclusions

Breathing exercises appears to complement exercise training towards improved dyspnea and HRQL in patients with IPF.

Idiopathic Pulmonary Fibrosis: Pathogenesis and the Emerging Role of Long Non-Coding RNAs

Idiopathic pulmonary fibrosis (IPF) is a progressive chronic disease characterized by excessing scarring of the lungs leading to irreversible decline in lung function. The aetiology and pathogenesis of the disease are still unclear, although lung fibroblast and epithelial cell activation, as well as the secretion of fibrotic and inflammatory mediators, have been strongly associated with the development and progression of IPF. Significantly, long non-coding RNAs (lncRNAs) are emerging as modulators of multiple biological processes, although their function and mechanism of action in IPF is poorly understood. LncRNAs have been shown to be important regulators of several diseases and their aberrant expression has been linked to the pathophysiology of fibrosis including IPF. This review will provide an overview of this emerging role of lncRNAs in the development of IPF.

Gaps in care of patients living with pulmonary fibrosis: a joint patient and expert statement on the results of a Europe-wide survey

Introduction

Pulmonary fibrosis (PF) and its most common form, idiopathic pulmonary fibrosis (IPF), are chronic, progressive diseases resulting in increasing loss of lung function and impaired quality of life and survival. The aim of this joint expert and patient statement was to highlight the most pressing common unmet needs of patients with PF/IPF, putting forward recommendations to improve the quality of life and health outcomes throughout the patient journey.

Methods

Two online surveys for patients and healthcare professionals (HCPs) were conducted by the European Idiopathic Pulmonary Fibrosis and Related Disorders Federation (EU-IPFF) in 14 European countries.

Results

The surveys were answered by 286 patients and 69 HCPs, including physicians and nurses. Delays in diagnosis and timely access to interstitial lung disease specialists and pharmacological treatment have been identified as important gaps in care. Additionally, patients and HCPs reported that a greater focus on symptom-centred management, adequate information, trial information and increasing awareness of PF/IPF is required.

Conclusions

The surveys offer important insights into the current unmet needs of PF/IPF patients. Interventions at different points of the care pathway are needed to improve patient experience.

Risk factors for diagnostic delay in idiopathic pulmonary fibrosis

Background

Surveys and retrospective studies of patients with idiopathic pulmonary fibrosis (IPF) have shown a significant diagnostic delay. However, the causes and risk factors for this delay are not known.

Methods

Dates at six time points before the IPF diagnosis (onset of symptoms, first contact to a general practitioner, first hospital contact, referral to an interstitial lung disease (ILD) centre, first visit at an ILD centre, and final diagnosis) were recorded in a multicentre cohort of 204 incident IPF patients. Based on these dates, the delay was divided into specific patient-related and healthcare-related delays. Demographic and clinical data were used to determine risk factors for a prolonged delay, using multivariate negative binomial regression analysis.

Results

The median diagnostic delay was 2.1 years (IQR: 0.9–5.0), mainly attributable to the patients, general practitioners and community hospitals. Male sex was a risk factor for patient delay (IRR: 3.84, 95% CI: 1.17–11.36, p = 0.006) and old age was a risk factor for healthcare delay (IRR: 1.03, 95% CI: 1.01–1.06, p = 0.004). The total delay was prolonged in previous users of inhalation therapy (IRR: 1.99, 95% CI: 1.40–2.88, p <  0.0001) but not in patients with airway obstruction. Misdiagnosis of respiratory symptoms was reported by 41% of all patients.

Conclusion

Despite increased awareness of IPF, the diagnostic delay is still 2.1 years. Male sex, older age and treatment attempts for alternative diagnoses are risk factors for a delayed diagnosis of IPF. Efforts to reduce the diagnostic delay should focus on these risk factors.

Trial registration

This study was registered at http://clinicaltrials.gov (NCT02772549) on May 10, 2016.

Electronic supplementary material

The online version of this article (10.1186/s12931-019-1076-0) contains supplementary material, which is available to authorized users.

Implementing an interstitial lung disease clinic improves survival without increasing health care resource utilization

BACKGROUND

Multidisciplinary collaboration is the cornerstone of interstitial lung disease (ILD) care. Delayed access to specialized care is associated with worse outcome. At the same time, the economic burden of ILD is high. We hypothesized that the establishment of a regional, dedicated ILD clinic would improve survival, but without necessarily causing an increase of health care resource utilization (HRU).

METHODS

A historic cohort (January 2000-June 2013, n = 127) and a specialized care cohort followed by a dedicated ILD clinic (July 2013-June 2016, n = 144) were compared. Patients with idiopathic pulmonary fibrosis were excluded, due to the impact of new anti-fibrotic agents. Patients' data were linked to multiple provincial health administrative datasets. HRU included hospitalizations, doctor and emergency visits, pulmonary (including chest x-ray, chest CT scans, pulmonary function tests, bronchoscopies), cardio-vascular investigations, and specific ILD therapies. HRU was calculated as annual rate by domain. Three-year survival from initial assessment was the secondary outcome.

RESULTS

The 2 cohorts were closely comparable in terms of specific ILD diagnosis, baseline lung function, comorbidities, neighbourhood income. There were overall no significant differences in terms of HRU. In the specialized care cohort, the use of non-steroid immunosuppressive therapies increased and survival significantly improved, despite significantly older age of patients at the time of initial assessment. Specialized ILD care was independently protective towards survival.

CONCLUSIONS

Specialized, multi-disciplinary ILD care in a dedicated regional clinic is associated with improved survival and does not cause an increase of HRU, supporting the institution of potentially more cost-effective care with specialized ILD clinics.

Association Between Pulmonary Vessel-Related Structures and Cryptogenic Fibrosing Alveolitis Using Derived Computed Tomography Among Chinese Patients

BACKGROUND The aim of this study was to assess the association between pulmonary vessel-related structures and cryptogenic fibrosing alveolitis (CFA) in a drug trial in a Chinese population using derived computed tomography (dCT) to evaluate functional reduction and survival. MATERIAL AND METHODS Discovery and validation cohorts were chosen separately by fulfilment of drug trial entry criteria, and we enrolled 269 and 292 consecutive patients, respectively. CFA patients who had undergone imaging based on volumetric non-contrast CT at our hospital were subjected to pulmonary vessel-related structure (PVS) measures and dCT to forecast mortality and reduction in reduced forced vital capacity of CFA. RESULTS The best forecaster of survival and reduction in terms of reduced forced vital capacity were found to be the dCT-generated outcomes in terms of PVS scores. Patients having less extensive disease highlighted the dCT outcomes through outperformance of CFA measures. When we used the cohort enhancement device, we found reduction in the requisite sample size of a CFA drug trial by 31% with the use of more than 5.0% dCT PVS score. CONCLUSIONS We found an association between CFA and PVS using dCT and it is far better than the results achieved so far by use of criterion standard measures. Additionally, reduction in the restrictive trial costs was also achieved by using cohort enhancement in a CFA drug trial setting, as PVS scores forced us to decrease the size of required CFA drug trial population by 30%. Interestingly, patients who had to take antifibrotic medication for longer periods had longer survival and less decreases forced vital capacity, as identified by PVS scores.

Predicting Outcomes in Idiopathic Pulmonary Fibrosis Using Automated Computed Tomographic Analysis

RATIONALE

Quantitative computed tomographic (CT) measures of baseline disease severity might identify patients with idiopathic pulmonary fibrosis (IPF) with an increased mortality risk. We evaluated whether quantitative CT variables could act as a cohort enrichment tool in future IPF drug trials.

OBJECTIVES

To determine whether computer-derived CT measures, specifically measures of pulmonary vessel-related structures (VRSs), can better predict functional decline and survival in IPF and reduce requisite sample sizes in drug trial populations.

METHODS

Patients with IPF undergoing volumetric noncontrast CT imaging at the Royal Brompton Hospital, London, and St. Antonius Hospital, Utrecht, were examined to identify pulmonary function measures (including FVC) and visual and computer-derived (CALIPER [Computer-Aided Lung Informatics for Pathology Evaluation and Rating] software) CT features predictive of mortality and FVC decline. The discovery cohort comprised 247 consecutive patients, with validation of results conducted in a separate cohort of 284 patients, all fulfilling drug trial entry criteria.

MEASUREMENTS AND MAIN RESULTS

In the discovery and validation cohorts, CALIPER-derived features, particularly VRS scores, were among the strongest predictors of survival and FVC decline. CALIPER results were accentuated in patients with less extensive disease, outperforming pulmonary function measures. When used as a cohort enrichment tool, a CALIPER VRS score greater than 4.4% of the lung was able to reduce the requisite sample size of an IPF drug trial by 26%.

CONCLUSIONS

Our study has validated a new quantitative CT measure in patients with IPF fulfilling drug trial entry criteria-the VRS score-that outperformed current gold standard measures of outcome. When used for cohort enrichment in an IPF drug trial setting, VRS threshold scores can reduce a required IPF drug trial population size by 25%, thereby limiting prohibitive trial costs. Importantly, VRS scores identify patients in whom antifibrotic medication prolongs life and reduces FVC decline.

Chitosan-alginate nano-carrier for transdermal delivery of pirfenidone in idiopathic pulmonary fibrosis

Pirfenidone (PFD) is one of the pyridine family components with anti-inflammatory, antifibrotic effects and US FDA approved for the treatment of idiopathic pulmonary fibrosis (IPF). Presently, PFD is administered orally and this has setbacks. Hence, it is important to eliminate the pharmacotherapeutic limitations of PFD. This research was carried out to study the possibility of transdermal delivery of PFD using chitosan-sodium alginate nanogel carriers. In order to synthesize chitosan-sodium alginate nanoparticles loaded with PFD, the pre-gelation method was used. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR) analyses were used for the characterization. Drug encapsulation and release manner were studied using UV spectroscopy. Ex vivo permeation examinations were performed using Franz diffusion cell and fluorescence microscopy. The results showed that nanoparticles having spherical morphology and size in the range of 80 nm were obtained. In vitro drug release profile represents sustained release during 24 h, while 50% and 94% are the loading capacity and efficiency, respectively. Also, the skin penetration of PFD loaded in nanoparticles was significantly increased as compared to PFD solution. The obtained results showed that synthesized nanoparticles can be considered as promising carriers for PFD delivery.

Synergistic role of HSP90α and HSP90β to promote myofibroblast persistence in lung fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive disease of the lung parenchyma, causing significant morbidity through worsening dyspnoea and overall functional decline. IPF is characterised by apoptosis-resistant myofibroblasts, which are a major source for the excessive production of extracellular matrix (ECM) overtaking normal lung tissue. We sought to study the role of heat shock protein (HSP) isoforms HSP90α and HSP90β, whose distinct roles in lung fibrogenesis remain elusive.We determined the level of circulating HSP90α in IPF patients (n=31) and age-matched healthy controls (n=9) by ELISA. The release of HSP90α and HSP90β was evaluated in vitro in primary IPF and control lung fibroblasts and ex vivo after mechanical stretch on fibrotic lung slices from rats receiving adenovector-mediated transforming growth factor-β1.We demonstrate that circulating HSP90α is upregulated in IPF patients in correlation with disease severity. The release of HSP90α is enhanced by the increase in mechanical stress of the fibrotic ECM. This increase in extracellular HSP90α signals through low-density lipoprotein receptor-related protein 1 (LRP1) to promote myofibroblast differentiation and persistence. In parallel, we demonstrate that the intracellular form of HSP90β stabilises LRP1, thus amplifying HSP90α extracellular action.We believe that the specific inhibition of extracellular HSP90α is a promising therapeutic strategy to reduce pro-fibrotic signalling in IPF.

Barriers to timely diagnosis of interstitial lung disease in the real world: the INTENSITY survey

Background

The diagnosis of idiopathic pulmonary fibrosis (IPF) and other interstitial lung diseases (ILD) presents significant clinical challenges. To gain insights regarding the diagnostic experience of patients with ILD and to identify potential barriers to a timely and accurate diagnosis, we developed an online questionnaire and conducted a national survey of adults with a self-reported diagnosis of ILD.

Methods

A pre-specified total of 600 subjects were recruited to participate in a 40-question online survey. E-mail invitations containing a link to the survey were sent to 16 427 registered members of the Pulmonary Fibrosis Foundation. Additionally, an open invitation was posted on an online forum for patients and caregivers (www.inspire.com). The recruitment and screening period was closed once the pre-defined target number of respondents was reached. Eligible participants were adult U.S. residents with a diagnosis of IPF or a non-IPF ILD.

Results

A total of 600 eligible respondents met the eligibility criteria and completed the survey. Of these, 55% reported ≥ 1 misdiagnosis and 38% reported ≥ 2 misdiagnoses prior to the current diagnosis. The most common misdiagnoses were asthma (13.5%), pneumonia (13.0%), and bronchitis (12.3%). The median time from symptom onset to current diagnosis was 7 months (range, 0–252 months), with 43% of respondents reporting a delay of ≥ 1 year and 19% reporting a delay of ≥ 3 years. Sixty-one percent of respondents underwent at least one invasive diagnostic procedure.

Conclusions

While a minority of patients with ILD will experience an appropriate and expedient diagnosis, the more typical diagnostic experience for individuals with ILD is characterized by considerable delays, frequent misdiagnosis, exposure to costly and invasive diagnostic procedures, and substantial use of healthcare resources. These findings suggest a need for physician education, development of clinical practice recommendations, and improved diagnostic tools aimed at improving diagnostic accuracy in patients with ILD.

Electronic supplementary material

The online version of this article (10.1186/s12890-017-0560-x) contains supplementary material, which is available to authorized users.

Are physicians in primary health care able to recognize pulmonary fibrosis?

Background: The early diagnosis of idiopathic pulmonary fibrosis (IPF) has become increasingly important due to evolving treatment options. IPF patients experience a significant delay in receiving an accurate diagnosis, thus delayed access to tertiary care is associated with higher mortality independently from disease severity. Objective: The aims were to evaluate whether there had been a delay in the referral process, and to determine whether the referring doctors had suspected IPF or other interstitial lung disease (ILD) already during the time of referral. Methods: Ninety-five referral letters of patients with IPF identified from the FinnishIPF registry were evaluated with respect to time of referral, referring unit, grounds for referral, symptoms, smoking status, occupational history, clinical examinations, co-morbidities, medication, radiological findings and lung function. Results: Fifty-nine percent of referral letters originated from primary public health care. The time from symptom onset to referral was reported in 60% of cases, mean time being 1.5 (0.8-2.3) (95%CI) years. The main reason for referral was a suspicion of interstitial lung disease (ILD) (63%); changes in chest X-ray were one reason for referring in 53% of cases. Lung auscultation was reported in 70% and inspiratory crackles in 52% of referral letters. Conclusions: Primary care doctors suspected lung fibrosis early in the course of disease. Lung auscultation and chest X-rays were the most common investigational abnormalities in the referrals. Providing general practitioners with more information of ILDs might shorten the delay from symptom onset to referral.

Ultrasound Strain Measurements for Evaluating Local Pulmonary Ventilation

Local lung function is difficult to evaluate, because most lung function estimates are either global in nature (e.g., pulmonary function tests) or require equipment that cannot be used at a patient's bedside, such as computed tomography. Yet, local function measurements would be highly desirable for many reasons. Recently, we were able to track displacements of the lung surface during breathing. We have now extended these results to measuring lung strains during respiration as a means of assessing local lung ventilation. We studied two human volunteers and 14 mice with either normal lung function or experimentally induced pulmonary fibrosis. The differences in strains between the control, normal mice and those with pulmonary fibrosis were significant (p < 0.0001), whereas the strains measured in the human volunteers closely matched linear strains predicted from the literature. It may be possible to use ultrasonography to assess local lung ventilation in a clinical setting.

Referral to Palliative Care Infrequent in Patients with Idiopathic Pulmonary Fibrosis Admitted to an Intensive Care Unit

BACKGROUND

Palliative care has been recommended as a means to assist patients with idiopathic pulmonary fibrosis (IPF) in managing symptom burden and advanced care planning. Timing of referral is important because although most patients display a gradually progressive course, a minority experience acute deterioration, an outcome associated with high mortality.

AIM

To describe characteristics of IPF patients referred to a specialty lung disease center over a 10-year period who experienced acute deterioration and subsequent intensive care unit (ICU) admission, including frequency and timing of referral to palliative care.

DESIGN

Retrospective review.

SETTING/PARTICIPANTS

We identified 106 patients admitted to the ICU with acute deterioration due to a respiratory or nonrespiratory cause. Variables examined included demographics, date of first center visit, forced vital capacity, diffusing capacity of the lung for carbon monoxide (DLCO), and palliative care referral.

RESULTS

ICU admission occurred early (median 9.5 months) and, for 34%, within four months of their first center visit. For nearly one-half of these patients, ICU admission occurred before their third clinic visit. Only 4 (3.8%) patients received a palliative care referral before ICU admission. The majority (77%) died during ICU admission. With exception of the relationship between DLCO% predicted at first visit and time to ICU admission (r = 0.32, p = 0.005), no variables identified those most likely to experience acute deterioration.

CONCLUSION

Due to high mortality associated with ICU admission, patients and families should be informed about palliative care early following diagnosis of IPF.

European IPF Patient Charter: unmet needs and a call to action for healthcare policymakers

Patient advocacy groups play an important role in supporting patients with chronic diseases and promoting better care. The aim of this patient–physician initiative was to gather perceptions from European idiopathic pulmonary fibrosis (IPF) patient advocacy groups regarding inequalities and unmet needs in IPF care, in order to develop a Patient Charter to advocate for better care.

In total, 11 European patient advocacy groups were interviewed regarding the care of patients with IPF in their countries. Interview feedback was presented to a Working Group including patient advocacy group representatives and IPF specialists; key areas of agreement were developed into the European IPF Patient Charter.

The interviews identified five key themes that fed into the final Charter: the need for improved diagnosis, treatment access, holistic care, disease awareness and palliative care. The final Charter was endorsed by patient advocacy groups and presented to 26 Members of the European Parliament in September 2014. It has received >8900 signatures to date.

This patient–physician initiative highlights the inequalities and unmet needs in IPF care across Europe, and demonstrates how this insight can inform the development of a Patient Charter, designed as a call to action for healthcare policymakers to drive improvement in European IPF care.

Ultrasound Strain Measurements for Evaluating Local Pulmonary Ventilation

Local lung function is difficult to evaluate, because most lung function estimates are either global in nature, e.g. pulmonary function tests, or require equipment that cannot be used at a patient's bedside, such as computed tomograms. Yet, local function measurements would be highly desirable for many reasons. In a recent publication [1], we were able to track displacements of the lung surface during breathing. We have now extended these results to measuring lung strains during respiration as a means of assessing local lung ventilation. We studied two normal human volunteers and 12 mice with either normal lung function or experimentally induced pulmonary fibrosis. The difference in strains between the control, normal mice and those with pulmonary fibrosis was significant (p < 0.02), while the strains measured in the human volunteers closely matched linear strains predicted from the literature. Ultrasonography may be able to assess local lung ventilation.

Organisation of diagnosis and treatment of idiopathic pulmonary fibrosis and other interstitial lung diseases in the Nordic countries

Introduction

Differences in the organisation of idiopathic pulmonary fibrosis (IPF) and interstitial lung diseases (ILDs) in the Nordic countries are not well described. Diagnostic setups, treatment modalities and follow-up plans may vary due to national, cultural and epidemiological features. The aim of the present study was to describe the different organisation of diagnostics and treatment of IPF and ILD in the Nordic countries.

Methods

All university and regional hospitals with respiratory physicians were invited to respond to a questionnaire collecting data on the number of physicians, nurses, patients with ILD/IPF, the presence of and adherence to disease-specific national and international guidelines, diagnosis and treatment including ILD-specific palliation and rehabilitation programmes.

Results

Twenty-four university and 22 regional hospitals returned the questionnaire. ILD and IPF incidence varied between 1.4 and 20/100,000 and 0.4 and 10/100,000, respectively. Denmark and Estonia have official national plans for the organisation of ILD. The majority of patients are managed at the university hospitals. The regional hospitals each manage 46 (5–200) patients with ILD and 10 (0–20) patients with IPF. There are from one to four ILD centres in each country with a median of two ILD specialists employed. Specialised ILD nurses are present in nine hospitals. None of the Nordic countries have national guidelines made by health authorities. The respiratory societies in Sweden, Norway and Denmark have developed national guidelines. All hospitals except two use the ATS/ERS/JRS/ALAT IPF guidelines from 2011. The limited number of ILD specialists, ILD-specialised radiologists and pathologists and the low volume of ILD centres were perceived as bottlenecks for implementation of guidelines. Twenty of the 24 university hospitals have multidisciplinary conferences (MDCs). Pulmonologists and radiologists take part in all MDCs while pathologists only participate at 17 hospitals. Prescription of pirfenidone is performed by all university hospitals except in Estonia. Triple therapy with steroid, azathioprine and N-acetylcysteine is not used. No hospitals have specific palliation programmes for patients with ILD/IPF, but 36 hospitals have the possibility of referring patients for palliative care, mostly based on existing oncology palliative care teams; seven hospitals have rehabilitation programmes for ILD.

Conclusion

There are obvious differences between the organisations of ILD patients in the Nordic countries. We call for national plans that consider the challenge of cultural and geographical differences and suggest the establishment of national reference centres and satellite collaborative hospitals to enable development of common guidelines for diagnostics, therapy and palliation in this patient group.