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

Use of Race-Specific Equations in Pulmonary Function Tests Impedes Potential Eligibility for Care and Treatment of Pulmonary Fibrosis

Rationale: The use of race-specific reference values to evaluate pulmonary function has long been embedded into clinical practice; however, there is a growing consensus that this practice may be inappropriate and that the use of race-neutral equations should be adopted to improve access to health care. Objectives: To evaluate whether the use of race-neutral equations to assess percent predicted forced vital capacity (FVC%pred) impacts eligibility for clinical trials, antifibrotic therapy, and referral for lung transplantation in Black, Hispanic/Latino, and White patients with interstitial lung disease (ILD). Methods: FVC%pred values for patients from the Pulmonary Fibrosis Foundation Patient Registry were calculated using race-specific (Hankinson and colleagues, 1999), race-agnostic (Global Lung Function Initiative [GLI]-2012), and race-neutral (GLI-2022 or GLI-Global) equations. Eligibility for ILD clinical trials (FVC%pred >45% and <90%), antifibrotic therapy (FVC%pred >55% and <82%), and lung transplantation referral (FVC%pred <70%) based on GLI-2022 and GLI-2012 equations were compared with those based on the Hankinson 1999 equation. Results: Baseline characteristics were available for 1,882 patients (Black, n = 104; Hispanic/Latino, n = 103; White, n = 1,675), and outcomes were evaluated in 1,531 patients with FVC%pred within ±90 days of registry enrollment (Black, n = 78; Hispanic/Latino, n = 72; White, n = 1,381). Black patients were younger at the time of consent and more likely to be female compared with Hispanic/Latino or White patients. Compared with GLI-2022, the Hankinson 1999 equation misclassified 22% of Black patients, 14% of Hispanic/Latino patients, and 12% of White patients for ILD clinical trial eligibility; 21% of Black patients, 17% of Hispanic/Latino patients, and 19% of White patients for antifibrotic therapy eligibility; and 6% of Black patients, 14% of Hispanic/Latino patients, and 12% of White patients for lung transplantation referral. Similar trends were observed when comparing the GLI-2012 and Hankinson 1999 equations. Conclusions: Misclassification of patients for critical interventions is highly prevalent when using the Hankinson 1999 equation and highlights the need to consider adopting the race-neutral GLI-2022 equation for enhanced accuracy and more equitable representation in pulmonary health care. Our results make a compelling case for reevaluating the use of race as a physiological variable and emphasize the pressing need for continuous innovation to ensure equal and optimal care for all patients regardless of their race or ethnicity. Clinical trial registered with www.clinicaltrials.gov (NCT02758808).

The future of clinical trials in idiopathic pulmonary fibrosis

PURPOSE OF REVIEW

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with a poor prognosis and limited therapeutic options. A multitude of promising compounds are currently being investigated; however, the design and conductance of late-phase clinical trials in IPF has proven particularly challenging.

RECENT FINDINGS

Despite promising phase 2 data, ziritaxestat, an autotaxin inhibitor, pentraxin-2, an endogenous protein that regulates wound healing and fibrosis, and pamrevlumab, a human monoclonal antibody against connective tissue growth factor, failed to show efficacy in phase 3 trials. Endpoint selection is critical for the design, execution, and success of clinical trials; recently, attention has been paid to the assessment of how patients feel, function, and survive with the aim of aligning scientific objectives and patient needs in IPF. External control arms are control patients that derive from historical randomized controlled trials, registries, or electronic health records. They are increasingly used to assess treatment efficacy in clinical trials owing to their potential to reduce study duration and cost and increase generalizability of findings.

SUMMARY

Advances in study design, end point selection and statistical analysis, and innovative strategies for more efficient enrolment of study participants have the potential to increase the likelihood of success of late-phase clinical trials in IPF.

A multidimensional classifier to support lung transplant referral in patients with pulmonary fibrosis

BACKGROUND

Lung transplantation remains the sole curative option for patients with idiopathic pulmonary fibrosis (IPF), but donor organs remain scarce, and many eligible patients die before transplant. Tools to optimize the timing of transplant referrals are urgently needed.

METHODS

Least absolute shrinkage and selection operator was applied to clinical and proteomic data generated as part of a prospective cohort study of interstitial lung disease (ILD) to derive clinical, proteomic, and multidimensional logit models of near-term death or lung transplant within 18 months of blood draw. Model-fitted values were dichotomized at the point of maximal sensitivity and specificity, and decision curve analysis was used to select the best-performing classifier. We then applied this classifier to independent IPF and non-IPF ILD cohorts to determine test performance characteristics. Cohorts were restricted to patients aged ≤72 years with body mass index 18 to 32 to increase the likelihood of transplant eligibility.

RESULTS

IPF derivation, IPF validation, and non-IPF ILD validation cohorts consisted of 314, 105, and 295 patients, respectively. A multidimensional model comprising 2 clinical variables and 20 proteins outperformed stand-alone clinical and proteomic models. Following dichotomization, the multidimensional classifier predicted near-term outcome with 70% sensitivity and 92% specificity in the IPF validation cohort and 70% sensitivity and 80% specificity in the non-IPF ILD validation cohort.

CONCLUSIONS

A multidimensional classifier of near-term outcomes accurately discriminated this end-point with good test performance across independent IPF and non-IPF ILD cohorts. These findings support refinement and prospective validation of this classifier in transplant-eligible individuals.

Surgical lung biopsy for Idiopathic Pulmonary Fibrosis: Is the risk-benefit ratio changing

See related article

The impact of antifibrotic use on long-term clinical outcomes in the pulmonary fibrosis foundation registry

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial lung disease (ILD) with a high mortality rate. The antifibrotic medications pirfenidone and nintedanib have been in use since 2014 for this disorder and are associated with improved rate of lung function decline. Less is known about their long-term outcomes outside of the clinical trial context.

METHODS

The Pulmonary Fibrosis Foundation Patient Registry was used for this study. Patients with an IPF diagnosis made within a year of enrollment were included. The treated group was defined as patients receiving either pirfenidone or nintedanib for at least 180 days. The untreated group did not have any record of antifibrotic use. Demographic data, comorbidities, serial lung function, hospitalization, and vital status data were collected from the registry database. The primary outcomes were transplant-free survival, time to first respiratory hospitalization, and time to 10% absolute FVC decline. Time-to-event analyses were performed utilizing Cox proportional hazards models and the log-rank test. Model covariates included age, gender, smoking history, baseline lung function, comorbidities, and oxygen use.

RESULTS

The registry contained 1212 patients with IPF; ultimately 288 patients met inclusion criteria for the treated group, and 101 patients were designated as untreated. Patients treated with antifibrotics were significantly younger (69.8 vs. 72.6 years, p = 0.008) and less likely to have smoked (61.1% ever smokers vs. 72.3% never smokers, p = 0.04). No significant differences were seen in race, gender, comorbidities, or baseline pulmonary function between groups. The primary outcome of transplant-free survival was not significantly different between the two groups (adjusted HR 0.799, 95% CI 0.534-1.197, p = 0.28). Time to respiratory hospitalization was significantly shorter in the treated group (adjusted HR 2.12, 95% CI 1.05-4.30, p = 0.04). No significant difference in time to pulmonary function decline was seen between groups.

CONCLUSIONS

This multicenter study demonstrated 63% of newly diagnosed IPF patients had continuous antifibrotic usage. Antifibrotics were not associated with improved transplant-free survival or pulmonary function change but was associated with an increased hazard of respiratory hospitalization. Future studies should further investigate the role of antifibrotic therapy in clinically important outcomes in real-world patients with IPF and other progressive ILDs.

Pursuing Clinical Predictors and Biomarkers for Progression in ILD: Analysis of the Pulmonary Fibrosis Foundation (PFF) Registry

INTRODUCTION

Pulmonary fibrosis is a characteristic of various interstitial lung diseases (ILDs) with differing etiologies. Clinical trials in progressive pulmonary fibrosis (PPF) enroll patients based on previously described clinical criteria for past progression, which include a clinical practice guideline for PPF classification and inclusion criteria from the INBUILD trial. In this study, we compared the ability of past FVC (forced vital capacity) progression and baseline biomarker levels to predict future progression in a cohort of patients from the PFF Patient Registry.

METHODS

Biomarkers previously associated with pathobiology and/or progression in pulmonary fibrosis were selected to reflect cellular senescence (telomere length), pulmonary epithelium (SP-D, RAGE), myeloid activation (CXCL13, YKL40, CCL18, OPN) and fibroblast activation (POSTN, COMP, PROC3).

RESULTS

PFF or INBUILD-like clinical criteria was used to separate patients into past progressor and non-past progressor groups, and neither clinical criterion appeared to enrich for patients with greater future lung function decline. All baseline biomarkers measured were differentially expressed in patient groups compared to healthy controls. Baseline levels of SP-D and POSTN showed the highest correlations with FVC slope over one year, though correlations were low.

CONCLUSIONS

Our findings provide further evidence that prior decline in lung function may not predict future disease progression for ILD patients, and elevate the need for molecular definitions of a progressive phenotype. Across ILD subtypes, certain shared pathobiologies may be present based on the molecular profile of certain biomarker groups observed. In particular, SP-D may be a common marker of pulmonary injury and future lung function decline across ILDs.

Deep Learning Classification of Usual Interstitial Pneumonia Predicts Outcomes

Rationale: Computed tomography (CT) enables noninvasive diagnosis of usual interstitial pneumonia (UIP), but enhanced image analyses are needed to overcome the limitations of visual assessment. Objectives: Apply multiple instance learning (MIL) to develop an explainable deep learning algorithm for prediction of UIP from CT and validate its performance in independent cohorts. Methods: We trained an MIL algorithm using a pooled dataset (n = 2,143) and tested it in three independent populations: data from a prior publication (n = 127), a single-institution clinical cohort (n = 239), and a national registry of patients with pulmonary fibrosis (n = 979). We tested UIP classification performance using receiver operating characteristic analysis, with histologic UIP as ground truth. Cox proportional hazards and linear mixed-effects models were used to examine associations between MIL predictions and survival or longitudinal FVC. Measurements and Main Results: In two cohorts with biopsy data, MIL improved accuracy for histologic UIP (area under the curve, 0.77 [n = 127] and 0.79 [n = 239]) compared with visual assessment (area under the curve, 0.65 and 0.71). In cohorts with survival data, MIL-UIP classifications were significant for mortality (n = 239, mortality to April 2021: unadjusted hazard ratio, 3.1; 95% confidence interval [CI], 1.96-4.91; P < 0.001; and n = 979, mortality to July 2022: unadjusted hazard ratio, 3.64; 95% CI, 2.66-4.97; P < 0.001). Individuals classified as UIP positive by the algorithm had a significantly greater annual decline in FVC than those classified as UIP negative (-88 ml/yr vs. -45 ml/yr; n = 979; P < 0.01), adjusting for extent of lung fibrosis. Conclusions: Computerized assessment using MIL identifies clinically significant features of UIP on CT. Such a method could improve confidence in radiologic assessment of patients with interstitial lung disease, potentially enabling earlier and more precise diagnosis.

Proteomic Biomarkers of Survival in Idiopathic Pulmonary Fibrosis

Rationale: Idiopathic pulmonary fibrosis (IPF) causes progressive lung scarring and high mortality. Reliable and accurate prognostic biomarkers are urgently needed. Objectives: To identify and validate circulating protein biomarkers of IPF survival. Methods: High-throughput proteomic data were generated using prospectively collected plasma samples from patients with IPF from the Pulmonary Fibrosis Foundation Patient Registry (discovery cohort) and the Universities of California, Davis; Chicago; and Virginia (validation cohort). Proteins associated with three-year transplant-free survival (TFS) were identified using multivariable Cox proportional hazards regression. Those associated with TFS after adjustment for false discovery in the discovery cohort were advanced for testing in the validation cohort, with proteins maintaining TFS association with consistent effect direction considered validated. After combining cohorts, functional analyses were performed, and machine learning was used to derive a proteomic signature of TFS. Measurements and Main Results: Of 2,921 proteins tested in the discovery cohort (n = 871), 231 were associated with differential TFS. Of these, 140 maintained TFS association with consistent effect direction in the validation cohort (n = 355). After cohorts were combined, the validated proteins with the strongest TFS association were latent-transforming growth factor β-binding protein 2 (hazard ratio [HR], 2.43; 95% confidence interval [CI] = 2.09-2.82), collagen α-1(XXIV) chain (HR, 2.21; 95% CI = 1.86-2.39), and keratin 19 (HR, 1.60; 95% CI = 1.47-1.74). In decision curve analysis, a proteomic signature of TFS outperformed a similarly derived clinical prediction model. Conclusions: In the largest proteomic investigation of IPF outcomes performed to date, we identified and validated 140 protein biomarkers of TFS. These results shed important light on potential drivers of IPF progression.

Associations of Plasma Omega-3 Fatty Acids With Progression and Survival in Pulmonary Fibrosis

BACKGROUND

Preclinical experiments suggest protective effects of omega-3 fatty acids and their metabolites in lung injury and fibrosis. Whether higher intake of omega-3 fatty acids is associated with disease progression and survival in humans with pulmonary fibrosis is unknown.

RESEARCH QUESTION

What are the associations of plasma omega-3 fatty acid levels (a validated marker of omega-3 nutritional intake) with disease progression and transplant-free survival in pulmonary fibrosis?

STUDY DESIGN AND METHODS

Omega-3 fatty acid levels were measured from plasma samples of patients with clinically diagnosed pulmonary fibrosis from the Pulmonary Fibrosis Foundation Patient Registry (n = 150), University of Virginia (n = 58), and University of Chicago (n = 101) cohorts. The N-3 index (docosahexaenoic acid + eicosapentaenoic acid) was the primary exposure variable of interest. Linear-mixed effects models with random intercept and slope were used to examine associations of plasma omega-3 fatty acid levels with changes in FVC and diffusing capacity for carbon monoxide over a period of 12 months. Cox proportional hazards models were used to examine transplant-free survival. Stratified analyses by telomere length were performed in the University of Chicago cohort.

RESULTS

Most of the cohort were patients with idiopathic pulmonary fibrosis (88%) and male patients (74%). One-unit increment in log-transformed N-3 index plasma level was associated with a change in diffusing capacity for carbon monoxide of 1.43 mL/min/mm Hg per 12 months (95% CI, 0.46-2.41) and a hazard ratio for transplant-free survival of 0.44 (95% CI, 0.24-0.83). Cardiovascular disease history, smoking, and antifibrotic usage did not significantly modify associations. Omega-3 fatty acid levels were not significantly associated with changes in FVC. Higher eicosapentaenoic acid plasma levels were associated with longer transplant-free survival among University of Chicago participants with shorter telomere length (P value for interaction = .02).

INTERPRETATION

Further research is needed to investigate underlying biological mechanisms and whether omega-3 fatty acids are a potential disease-modifying therapy.

Deep Learning-based Fibrosis Extent on Computed Tomography Predicts Outcome of Fibrosing Interstitial Lung Disease Independent of Visually Assessed Computed Tomography Pattern

Rationale: Radiologic pattern has been shown to predict survival in patients with fibrosing interstitial lung disease. The additional prognostic value of fibrosis extent by quantitative computed tomography (CT) is unknown. Objectives: We hypothesized that fibrosis extent provides information beyond visually assessed CT pattern that is useful for outcome prediction. Methods: We performed a retrospective analysis of chest CT, demographics, longitudinal pulmonary function, and transplantation-free survival among participants in the Pulmonary Fibrosis Foundation Patient Registry. CT pattern was classified visually according to the 2018 usual interstitial pneumonia criteria. Extent of fibrosis was objectively quantified using data-driven textural analysis. We used Kaplan-Meier plots and Cox proportional hazards and linear mixed-effects models to evaluate the relationships between CT-derived metrics and outcomes. Results: Visual assessment and quantitative analysis were performed on 979 enrollment CT scans. Linear mixed-effect modeling showed that greater baseline fibrosis extent was significantly associated with the annual rate of decline in forced vital capacity. In multivariable models that included CT pattern and fibrosis extent, quantitative fibrosis extent was strongly associated with transplantation-free survival independent of CT pattern (hazard ratio, 1.04; 95% confidence interval, 1.04-1.05; P < 0.001; C statistic = 0.73). Conclusions: The extent of lung fibrosis by quantitative CT is a strong predictor of physiologic progression and survival, independent of visually assessed CT pattern.

Supplemental Oxygen Therapy in Interstitial Lung Disease: A Narrative Review

Patients with interstitial lung diseases (ILD) often have hypoxemia at rest and/or with exertion, for which supplemental oxygen is commonly prescribed. The number of patients with ILD who require supplemental oxygen is unknown, although estimates suggest it could be as much as 40%; many of these patients may require high-flow support (>4 L/min). Despite its frequent use, there is limited evidence for the impact of supplemental oxygen on clinical outcomes in ILD, with recommendations for its use primarily based on older studies in patients with chronic obstructive pulmonary disease. Oxygen use in ILD is rarely included as an outcome in clinical trials. Available evidence suggests that supplemental oxygen in ILD may improve quality of life and some exercise parameters in patients whose hypoxemia is a limiting factor; however, oxygen therapy also places new burdens and barriers on some patients that may counter its beneficial effects. The cost of supplemental oxygen in ILD is also unknown but likely represents a significant portion of overall healthcare costs in these patients. Current Centers for Medicare and Medicaid reimbursement policies provide only a modest increase in payment for high oxygen flows, which may negatively impact access to oxygen services and equipment for some patients with ILD. Future studies should examine clinical and quality-of-life outcomes for oxygen use in ILD. In the meantime, given the current limited evidence for supplemental oxygen and considering cost factors and other barriers, providers should take a patient-focused approach when considering supplemental oxygen prescriptions in patients with ILD.

Walking the path of treatable traits in interstitial lung diseases

Interstitial lung diseases (ILDs) are complex and heterogeneous diseases. The use of traditional diagnostic classification in ILD can lead to suboptimal management, which is worsened by not considering the molecular pathways, biological complexity, and disease phenotypes. The identification of specific "treatable traits" in ILDs, which are clinically relevant and modifiable disease characteristics, may improve patient's outcomes. Treatable traits in ILDs may be classified into four different domains (pulmonary, aetiological, comorbidities, and lifestyle), which will facilitate identification of related assessment tools, treatment options, and expected benefits. A multidisciplinary care team model is a potential way to implement a "treatable traits" strategy into clinical practice with the aim of improving patients' outcomes. Multidisciplinary models of care, international registries, and the use of artificial intelligence may facilitate the implementation of the "treatable traits" approach into clinical practice. Prospective studies are needed to test potential therapies for a variety of treatable traits to further advance care of patients with ILD.

External Control Arms in Idiopathic Pulmonary Fibrosis Using Clinical Trial and Real-World Data Sources

Rationale: Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease for which novel therapies are needed. External controls (ECs) could enhance IPF trial efficiency, but the direct comparability of ECs versus concurrent controls is unknown. Objectives: To develop IPF ECs by fit-for-purpose data standards to historical randomized clinical trial (RCT), multicenter registry (Pulmonary Fibrosis Foundation Patient Registry), and electronic health record (EHR) data and to evaluate endpoint comparability among ECs and the phase II RCT of BMS-986020. Methods: After data curation, the rate of change in FVC from baseline to 26 weeks among participants receiving BMS-986020 600 mg twice daily was compared with the BMS-placebo arm and ECs using mixed-effects models with inverse probability weights. Measurements and Main Results: At 26 weeks, the rates of change in FVC were -32.71 ml for BMS-986020 and -130.09 ml for BMS-placebo (difference, 97.4 ml; 95% confidence interval [CI], 24.6-170.2), replicating the original BMS-986020 RCT. RCT ECs showed treatment effect point estimates within the 95% CI of the original BMS-986020 RCT. Pulmonary Fibrosis Foundation Patient Registry ECs and EHR ECs experienced a slower rate of FVC decline compared with the BMS-placebo arm, resulting in treatment-effect point estimates outside of the 95% CI of the original BMS-986020 RCT. Conclusions: IPF ECs generated from historical RCT placebo arms result in comparable primary treatment effects to that of the original clinical trial, whereas ECs from real-world data sources, including registry or EHR data, do not. RCT ECs may serve as a potentially useful supplement to future IPF RCTs.

Validity and Reliability of the Fatigue Severity Scale in a Real-World Interstitial Lung Disease Cohort

Rationale: Fatigue is a common and debilitating symptom for people living with interstitial lung disease (ILD). Studies on fatigue in ILD are limited, and little headway has been made toward developing interventions targeting the alleviation of fatigue. A barrier to progress is a lack of knowledge around the performance characteristics of a patient-reported outcome measure to assess fatigue in patients with ILD. Objectives: To assess the validity and reliability of the Fatigue Severity Scale (FSS) for measuring fatigue in a national cohort of patients with ILD. Methods: FSS scores and several anchors were measured in 1,881 patients from the Pulmonary Fibrosis Foundation Patient Registry. Anchors included the Short Form 6D Health Utility Index (SF-6D) score and a single vitality question from the SF-6D; the University of California, San Diego, Shortness of Breath Questionnaire; FVC; DlCO; and 6-minute-walk distance. Internal consistency reliability, concurrent validity, and known-groups validity were assessed. Structural validity was assessed using confirmatory factor analysis. Measurements and Main Results: The FSS demonstrated high internal consistency (Cronbach's α = 0.96). There were moderate to strong correlations between FSS score and patient-reported anchors (vitality question from the SF-6D [r = 0.55] and University of California, San Diego, Shortness of Breath Questionnaire total score [r = 0.70]) and weak correlations between FSS score and physiological measures (FVC [r = -0.24], percentage predicted DlCO [r = -0.23], and 6-minute-walk distance [r = -0.29]). Higher mean FSS scores, indicating greater fatigue, were observed among patients using supplemental oxygen, those prescribed steroids, and those with lower percentage predicted FVC and percentage predicted DlCO. The confirmatory factor analysis results suggest that the nine questions of the FSS reflect one dimension of fatigue. Conclusions: Fatigue is an important patient-centered outcome in ILD that is poorly correlated with physiological measures of disease severity, including lung function and walk distance. These findings further support the need for a reliable and valid measure of patient-reported fatigue in ILD. The FSS possesses acceptable performance characteristics for assessing fatigue and distinguishing different degrees of fatigue among patients with ILD.

External validation and longitudinal application of the DO-GAP index to individualise survival prediction in idiopathic pulmonary fibrosis

Background

The Distance-Oxygen-Gender-Age-Physiology (DO-GAP) index has been shown to improve prognostication in idiopathic pulmonary fibrosis (IPF) compared to the Gender-Age-Physiology (GAP) score. We sought to externally validate the DO-GAP index compared to the GAP index for baseline risk assessment in patients with IPF. Additionally, we evaluated the utility of serial change in the DO-GAP index in predicting survival.

Methods

We performed an analysis of patients with IPF from the Pulmonary Fibrosis Foundation-Patient Registry (PFF-PR). Discrimination and calibration of the two models were assessed to predict transplant-free survival and IPF-related mortality. Joint longitudinal time-to-event modelling was utilised to individualise survival prediction based on DO-GAP index trajectory.

Results

There were 516 patients with IPF from the PFF-PR with available demographics, pulmonary function tests, 6-min walk test data and outcomes included in this analysis. The DO-GAP index (C-statistic: 0.73) demonstrated improved discrimination in discerning transplant-free survival compared to the GAP index (C-statistic: 0.67). DO-GAP index calibration was adequate, and the model retained predictive accuracy to identify IPF-related mortality (C-statistic: 0.74). The DO-GAP index was similarly accurate in the subset of patients taking antifibrotic medications. Serial change in the DO-GAP index improved model discrimination (cross-validated area under the curve: 0.83) enabling the personalised prediction of disease trajectory in individual patients.

Conclusion

The DO-GAP index is a simple, validated, multidimensional score that accurately predicts transplant-free survival in patients with IPF and can be adapted longitudinally in individual patients. The DO-GAP may also find use in studies of IPF to risk stratify patients and possibly as a clinical trial end-point.

Evaluation of Pulmonary Fibrosis Outcomes by Race and Ethnicity in US Adults

Importance

Pulmonary fibrosis (PF) is characterized by progressive scarring of lung tissue and poor survival. Racial and ethnic minority populations face the greatest risk of morbidity and mortality from disparities impacting respiratory health, but the pattern of age at clinically relevant outcomes across diverse racial and ethnic populations with PF is unknown.

Objective

To compare the age at PF-related outcomes and the heterogeneity in survival patterns among Hispanic, non-Hispanic Black, and non-Hispanic White participants.

Design, Setting, and Participants

This cohort study included adult patients with a PF diagnosis and used data from prospective clinical registries: the Pulmonary Fibrosis Foundation Registry (PFFR) for the primary cohort and registries from 4 geographically distinct tertiary hospitals in the US for the external multicenter validation (EMV) cohort. Patients were followed between January 2003 and April 2021.

Exposures

Race and ethnicity comparisons between Black, Hispanic, and White participants with PF.

Main Outcomes and Measures

Age and sex distribution of participants were measured at the time of study enrollment. All-cause mortality and age at PF diagnosis, hospitalization, lung transplant, and death were assessed in participants over 14 389 person-years. Differences between racial and ethnic groups were compared using Wilcoxon rank sum tests, Bartlett 1-way analysis of variance, and χ2 tests, and crude mortality rates and rate ratios were assessed across racial and ethnic categories using Cox proportional hazards regression models.

Results

In total, 4792 participants with PF were assessed (mean [SD] age, 66.1 [11.2] years; 2779 [58.0%] male; 488 [10.2%] Black, 319 [6.7%] Hispanic, and 3985 [83.2%] White); 1904 were in the PFFR and 2888 in the EMV cohort. Black patients with PF were consistently younger than White patients (mean [SD] age at baseline, 57.9 [12.0] vs 68.6 [9.6] years; P < .001). Hispanic and White patients were predominantly male (Hispanic: PFFR, 73 of 124 [58.9%] and EMV, 109 of 195 [55.9%]; and White: PFFR, 1090 of 1675 [65.1%] and EMV, 1373 of 2310 [59.4%]), while Black patients were less likely to be male (PFFR, 32 of 105 [30.5%] and EMV, 102 of 383 [26.6%]). Compared with White patients, Black patients had a lower crude mortality rate ratio (0.57 [95% CI, 0.31-0.97), but for Hispanic patients, the mortality rate ratio was similar to that of White patients (0.89; 95% CI, 0.57-1.35). Mean (SD) hospitalization events per person were highest among Black patients compared with Hispanic and White patients (Black: 3.6 [5.0]; Hispanic, 1.8 [1.4]; and White, 1.7 [1.3]; P < .001). Black patients were consistently younger than Hispanic and White patients at first hospitalization (mean [SD] age: Black, 59.4 [11.7] years; Hispanic, 67.5 [9.8] years; and White, 70.0 [9.3] years; P < .001), lung transplant (Black, 58.6 [8.6] years; Hispanic, 60.5 [6.1] years; and White, 66.9 [6.7] years; P < .001), and death (Black, 68.7 [8.4] years; Hispanic, 72.9 [7.6] years; and White, 73.5 [8.7] years; P < .001). These findings remained consistent in the replication cohort and in sensitivity analyses within prespecified deciles of age groups.

Conclusions and Relevance

In this cohort study of participants with PF, racial and ethnic disparities, especially among Black patients, were found in PF-related outcomes, including earlier onset of death. Further research is essential to identify and mitigate the underlying responsible factors.

PM2.5 and constituent component impacts on global DNA methylation in patients with idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive interstitial lung disease (ILD) whose outcomes are worsened with air pollution exposures. DNA methylation (DNAm) patterns are altered in lungs and blood from patients with IPF, but the relationship between air pollution exposures and DNAm patterns in IPF remains unexplored. This study aimed to evaluate the association of PM_2.5 and constituent components with global DNAm in patients with IPF. Patients enrolled in either the University of Pittsburgh Simmons Center for ILD Registry (Simmons) or the U.S.-wide Pulmonary Fibrosis Foundation (PFF) Patient Registry with peripheral blood DNA samples were included. The averages of monthly exposures to PM_2.5 and constituents over 1-year and 3-months pre-blood collection were matched to patient residential coordinates using satellite-derived hybrid models. Global DNAm percentage (%5 mC) was determined using the ELISA-based MethylFlash assay. Associations of pollutants with %5 mC were assessed using beta-regression, Cox models for mortality, and linear regression for baseline lung function. Mediation proportion was determined for models where pollutant-mortality and pollutant-%5 mC associations were significant. Inclusion criteria were met by 313 Simmons and 746 PFF patients with IPF. Higher PM_2.5 3-month exposures prior to blood collection were associated with higher %5 mC in Simmons (β = 0.02, 95%CI 0.0003-0.05, p = 0.047), with trends in the same direction in the 1-year period in both cohorts. Higher exposures to sulfate, nitrate, ammonium, and black carbon constituents were associated with higher %5 mC in multiple models. Percent 5 mC was not associated with IPF mortality or lung function, but was found to mediate between 2 and 5% of the associations of PM_2.5, sulfate, and ammonium with mortality. In conclusion, we found that higher global DNAm is a novel biomarker for increased PM_2.5 and anthropogenic constituent exposure in patients with IPF. Mechanistic research is needed to determine if DNAm has pathogenic relevance in mediating associations between pollutants and mortality in IPF.

Real-World Clinical Outcomes Based on Body Mass Index and Annualized Weight Change in Patients with Idiopathic Pulmonary Fibrosis

INTRODUCTION

Identification of clinical characteristics associated with prognosis for idiopathic pulmonary fibrosis (IPF) may help to guide management decisions. This analysis utilized data from the Pulmonary Fibrosis Foundation Patient Registry to examine the relationships between clinical outcomes and both body mass index (BMI) at study enrollment (hereafter referred to as baseline BMI) and annualized percent change in body weight in patients with IPF in a real-world setting.

METHODS

The following outcomes over 24 months were stratified by baseline BMI and annualized percent change in body weight: all-cause mortality; annualized change in percent predicted forced vital capacity (%FVC), percent predicted diffusing capacity for carbon monoxide, and 6-min walk distance; all-cause and respiratory-related hospitalizations; and acute exacerbations.

RESULTS

Overall, 600 patients with IPF were included (baseline BMI: < 25 kg/m², n = 120; 25 to < 30 kg/m², n = 242; ≥ 30 kg/m², n = 238; annualized percent change in body weight: no loss, n = 95; > 0% to < 5% loss, n = 425; ≥ 5% loss, n = 80). Enrollment demographics and characteristics were generally similar across subgroups. There was no association between mortality and BMI. All-cause mortality was lower among patients who experienced no annualized weight loss versus those with ≥ 5% (OR [95% CI] 3.28 [1.15, 10.95]) or > 0 to < 5% weight loss (OR [95% CI] 2.83 [1.14, 8.62]) over 24 months. Patients with baseline BMI < 25 kg/m² had a significantly greater estimated annualized decline in %FVC versus patients with baseline BMI ≥ 30 kg/m² (difference [95% CI] 1.47 [0.01, 2.93]). No relationship was observed between %FVC and weight loss. Other clinical outcomes were generally similar across subgroups.

CONCLUSIONS

Some clinical outcomes may be worse in patients with IPF who have a low BMI (< 25 kg/m²) or who experience weight loss over 24 months, but the causation for these relationships is unknown. These results may help to inform management decisions for patients with IPF.

CLINICALTRIALS

GOV IDENTIFIER

NCT02758808.

Design and rationale for the prospective treatment efficacy in IPF using genotype for NAC selection (PRECISIONS) clinical trial

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with few treatment options. N-acetylcysteine (NAC) is a well-tolerated, inexpensive treatment with antioxidant and anti-fibrotic properties. The National Heart, Lung, and Blood Institute (NHLBI)-sponsored PANTHER (Prednisone Azathioprine and NAC therapy in IPF) trial confirmed the harmful effects of immunosuppression in IPF, and did not show a benefit to treatment with NAC. However, a post hoc analysis revealed a potential beneficial effect of NAC in a subgroup of individuals carrying a specific genetic variant, TOLLIP rs3750920 TT genotype, present in about 25% of patients with IPF. Here, we present the design and rationale for the Phase III, multi-center, randomized, double-blind, placebo-controlled Prospective Treatment Efficacy in IPF Using Genotype for NAC Selection (PRECISIONS) clinical trial.

METHODS

The PRECISIONS trial will randomize 200 patients with IPF and the TOLLIP rs3750920 TT genotype 1:1 to oral N-acetylcysteine (600 mg tablets taken three times a day) or placebo for a 24-month duration. The primary endpoint is the composite of time to 10% relative decline in forced vital capacity (FVC), first respiratory hospitalization, lung transplantation, or death from any cause. Secondary endpoints include change in patient-reported outcome scores and proportion of participants with treatment-emergent adverse events. Biospecimens, including blood, buccal, and fecal will be collected longitudinally for future research purposes. Study participants will be offered enrollment in a home spirometry substudy, which explores time to 10% relative FVC decline measured at home, and its comparison with study visit FVC.

DISCUSSION

The sentinel observation of a potential pharmacogenetic interaction between NAC and TOLLIP polymorphism highlights the urgent, unmet need for better, molecularly focused, and precise therapeutic strategies in IPF. The PRECISIONS clinical trial is the first study to use molecularly-focused techniques to identify patients with IPF most likely to benefit from treatment. PRECISIONS has the potential to shift the paradigm in how trials in this condition are designed and executed, and is the first step toward personalized medicine for patients with IPF. Trial Registration ClinicalTrials.gov identifier: NCT04300920. Registered March 9, 2020. https://clinicaltrials.gov/ct2/show/NCT04300920.

Association of Particulate Matter Exposure With Lung Function and Mortality Among Patients With Fibrotic Interstitial Lung Disease

Importance

Particulate matter 2.5 μm or less in diameter (PM2.5) is associated with adverse outcomes for patients with idiopathic pulmonary fibrosis, but its association with other fibrotic interstitial lung diseases (fILDs) and the association of PM2.5 composition with adverse outcomes remain unclear.

Objective

To investigate the association of PM2.5 exposure with mortality and lung function among patients with fILD.

Design, Setting, and Participants

In this multicenter, international, prospective cohort study, patients were enrolled in the Simmons Center for Interstitial Lung Disease Registry at the University of Pittsburgh in Pittsburgh, Pennsylvania; 42 sites of the Pulmonary Fibrosis Foundation Registry; and 8 sites of the Canadian Registry for Pulmonary Fibrosis. A total of 6683 patients with fILD were included (Simmons, 1424; Pulmonary Fibrosis Foundation, 1870; and Canadian Registry for Pulmonary Fibrosis, 3389). Data were analyzed from June 1, 2021, to August 2, 2022.

Exposures

Exposure to PM2.5 and its constituents was estimated with hybrid models, combining satellite-derived aerosol optical depth with chemical transport models and ground-based PM2.5 measurements.

Main Outcomes and Measures

Multivariable linear regression was used to test associations of exposures 5 years before enrollment with baseline forced vital capacity and diffusion capacity for carbon monoxide. Multivariable Cox models were used to test associations of exposure in the 5 years before censoring with mortality, and linear mixed models were used to test associations of exposure with a decrease in lung function. Multiconstituent analyses were performed with quantile-based g-computation. Cohort effect estimates were meta-analyzed. Models were adjusted for age, sex, smoking history, race, a socioeconomic variable, and site (only for Pulmonary Fibrosis Foundation and Canadian Registry for Pulmonary Fibrosis cohorts).

Results

Median follow-up across the 3 cohorts was 2.9 years (IQR, 1.5-4.5 years), with death for 28% of patients and lung transplant for 10% of patients. Of the 6683 patients in the cohort, 3653 were men (55%), 205 were Black (3.1%), and 5609 were White (84.0%). Median (IQR) age at enrollment across all cohorts was 66 (58-73) years. A PM2.5 exposure of 8 μg/m3 or more was associated with a hazard ratio for mortality of 4.40 (95% CI, 3.51-5.51) in the Simmons cohort, 1.71 (95% CI, 1.32-2.21) in the Pulmonary Fibrosis Foundation cohort, and 1.45 (95% CI, 1.18-1.79) in the Canadian Registry for Pulmonary Fibrosis cohort. Increasing exposure to sulfate, nitrate, and ammonium PM2.5 constituents was associated with increased mortality across all cohorts, and multiconstituent models demonstrated that these constituents tended to be associated with the most adverse outcomes with regard to mortality and baseline lung function. Meta-analyses revealed consistent associations of exposure to sulfate and ammonium with mortality and with the rate of decrease in forced vital capacity and diffusion capacity of carbon monoxide and an association of increasing levels of PM2.5 multiconstituent mixture with all outcomes.

Conclusions and Relevance

This cohort study found that exposure to PM2.5 was associated with baseline severity, disease progression, and mortality among patients with fILD and that sulfate, ammonium, and nitrate constituents were associated with the most harm, highlighting the need for reductions in human-derived sources of pollution.

High-Resolution Computed Tomography of Fibrotic Interstitial Lung Disease

While radiography is the first-line imaging technique for evaluation of pulmonary disease, high-resolution computed tomography (HRCT) provides detailed assessment of the lung parenchyma and interstitium, allowing normal anatomy to be differentiated from superimposed abnormal findings. The fibrotic interstitial lung diseases have HRCT features that include reticulation, traction bronchiectasis and bronchiolectasis, honeycombing, architectural distortion, and volume loss. The characterization and distribution of these features result in distinctive CT patterns. The CT pattern and its progression over time can be combined with clinical, serologic, and pathologic data during multidisciplinary discussion to establish a clinical diagnosis. Serial examinations identify progression, treatment response, complications, and can assist in determining prognosis. This article will describe the technique used to perform HRCT, the normal and abnormal appearance of the lung on HRCT, and the CT patterns identified in common fibrotic lung diseases.

Acupuncture Case Registry Study: Rationale, Implementations, and Achievements

The acupuncture case registry study is focusing on acupuncture therapy data from patient cases. The main objective is to collect real-world data and integrate clinically meaningful outcome evaluation indicators to uncover and evaluate real-world acupuncture efficacy and safety, explore factors affecting acupuncture efficacy, and provide real-world evidence to complement RCTs. Since the International Acupuncture Case Registry data collection system’s establishment in 2017, 16 projects have been underway, including two acupuncture specialty therapies and 15 diseases. Data from 3404 patients included extensive information on the diagnosis and treatment of acupuncture and the evaluation of its efficacy. In order to serve as a guide for future studies, this article discusses the value of and rationale for establishing acupuncture case registry studies, how to distinguish them from patient registries, and crucial techniques for implementing registry studies in terms of applications, patient recruitment, costakeholder collaboration, data collection and management, study quality control, and ethics.

Diagnosing interstitial lung disease by multidisciplinary discussion: A review

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

Cough-Specific Quality of Life Predicts Disease Progression Among Patients With Interstitial Lung Disease: Data From the Pulmonary Fibrosis Foundation Patient Registry

BACKGROUND

Cough is a common symptom of interstitial lung disease (ILD) and negatively impacts health-related quality of life (QOL). Previous studies have shown that among patients with idiopathic pulmonary fibrosis, cough may predict progression of lung disease and perhaps even respiratory hospitalizations and mortality.

RESEARCH QUESTION

Does cough-specific QOL predict disease progression, respiratory hospitalization, lung transplantation, and death among patients with ILD?

STUDY DESIGN AND METHODS

We analyzed data from the Pulmonary Fibrosis Foundation Registry, which comprises a multicenter population of well-characterized patients with ILD. We first examined associations between patient factors and baseline scores on the Leicester Cough Questionnaire (LCQ), a cough-specific QOL tool, using a proportional odds model. Next, we examined associations between baseline LCQ scores and patient-centered clinical outcomes, as well as pulmonary function parameters, using a univariable and multivariable proportional hazards model that was adjusted for clinically relevant variables, including measures of disease severity.

RESULTS

One thousand four hundred forty-seven patients with ILD were included in our study. In the multivariable proportional odds model, we found that the following patient factors were associated with worse cough-specific QOL: younger age, diagnosis of "other ILD," gastroesophageal reflux disease, and lower FVC % predicted. Multivariable Cox regression models, adjusting for several variables including baseline disease severity, showed that a 1-point decrease in LCQ score (indicating lower cough-specific QOL) was associated with a 6.5% higher risk of respiratory-related hospitalization (hazard ratio [HR], 1.065; 95% CI, 1.025-1.107), a 7.4% higher risk of death (HR, 1.074; 95% CI, 1.020-1.130), and an 8.7% higher risk of lung transplantation (HR, 1.087; 95% CI, 1.022-1.156).

INTERPRETATION

Among a large population of well-characterized patients with ILD, cough-specific QOL was associated independently with respiratory hospitalization, death, and lung transplantation.

Safety and tolerability of nintedanib in patients with progressive fibrosing interstitial lung diseases: data from the randomized controlled INBUILD trial

Background

In the INBUILD trial in patients with progressive fibrosing interstitial lung diseases (ILDs), nintedanib reduced the rate of decline in forced vital capacity compared with placebo, with side-effects that were manageable for most patients. We used data from the INBUILD trial to characterize further the safety and tolerability of nintedanib.

Methods

Patients with fibrosing ILDs other than idiopathic pulmonary fibrosis (IPF), who had experienced progression of ILD within the 24 months before screening despite management deemed appropriate in clinical practice, were randomized to receive nintedanib 150 mg twice daily or placebo. To manage adverse events, treatment could be interrupted or the dose reduced to 100 mg twice daily. We assessed adverse events and dose adjustments over the whole trial.

Results

A total of 332 patients received nintedanib and 331 received placebo. Median exposure to trial drug was 17.4 months in both treatment groups. Adverse events led to treatment discontinuation in 22.0% of patients treated with nintedanib and 14.5% of patients who received placebo. The most frequent adverse event was diarrhea, reported in 72.3% of patients in the nintedanib group and 25.7% of patients in the placebo group. Diarrhea led to treatment discontinuation in 6.3% of patients in the nintedanib group and 0.3% of the placebo group. In the nintedanib and placebo groups, respectively, 48.2% and 15.7% of patients had ≥ 1 dose reduction and/or treatment interruption. Serious adverse events were reported in 44.3% of patients in the nintedanib group and 49.5% of patients in the placebo group. The adverse event profile of nintedanib was generally consistent across subgroups based on age, sex, race and weight, but nausea, vomiting and dose reductions were more common among female than male patients.

Conclusions

The adverse event profile of nintedanib in patients with progressive fibrosing ILDs other than IPF is consistent with its established safety and tolerability profile in patients with IPF and characterized mainly by gastrointestinal events, particularly diarrhea. Management of adverse events using symptomatic therapies and dose adjustment is important to minimize the impact of adverse events and help patients remain on therapy.

Trial registration Registered 21 December 2016, https://clinicaltrials.gov/ct2/show/NCT02999178

Graphical Abstract

A video abstract summarizing the key results presented in this manuscript is available at: https://www.globalmedcomms.com/respiratory/cottin/INBUILDsafety.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01974-2.

Developing a conceptual model of symptoms and impacts in progressive fibrosing interstitial lung disease to evaluate patient-reported outcome measures

Background

An understanding of the experience of patients with progressive fibrosing interstitial lung disease (PF-ILD) is needed to select appropriate patient-reported outcome measures (PROMs) to evaluate treatment effect in clinical trials.

Methods

A systematic literature review was conducted to develop a preliminary conceptual model of the symptoms experienced by patients with PF-ILD and the impacts the disease has on them. An online survey and consensus meetings were then conducted with 12-14 stakeholders (patients, clinicians, regulatory and payer advisors) to refine the conceptual model and critically appraise how key concepts should be measured by PROMs. PROMs assessed included Living with Idiopathic Pulmonary Fibrosis, Living with Pulmonary Fibrosis, the King's Brief Interstitial Lung Disease questionnaire, Cough and Sputum Assessment Questionnaire, Evaluating Respiratory Symptoms, Leicester Cough Questionnaire, Functional Assessment of Chronic Illness Therapy (Dyspnoea/Fatigue) and St George's Respiratory Questionnaire for Idiopathic Pulmonary Fibrosis.

Results

The literature review identified 36 signs/symptoms and 43 impacts directly or indirectly related to pulmonary aspects of PF-ILD. The most relevant symptoms identified by participants included shortness of breath on exertion, fatigue and cough; relevant impacts included effects on physical functioning, activities of daily living and emotional wellbeing. These are presented in a conceptual model. Consensus opinion was that existing PROMs need further modification and validation before use in clinical trials.

Conclusions

The conceptual model improves understanding of the symptoms and impacts that living with PF-ILD has on patients' wellbeing. It can help to inform the choice of PROMs in clinical trials and highlight aspects to assess in the clinical care of patients with PF-ILD.

Hypersensitivity pneumonitis: Current concepts in pathogenesis, diagnosis, and treatment

Hypersensitivity pneumonitis is an immune-mediated interstitial lung disease caused by an aberrant response to an inhaled exposure, which results in mostly T cell-mediated inflammation, granuloma formation, and fibrosis in some cases. HP is diagnosed by exposure identification, HRCT findings of ground-glass opacities, centrilobular nodules, and mosaic attenuation, with traction bronchiectasis and honeycombing in fibrotic cases. Additional testing including serum IgG testing for the presence of antigen exposure, bronchoalveolar lavage lymphocytosis, and lung biopsy demonstrating granulomas, inflammation, and fibrosis, increases the diagnostic confidence. Treatment for HP includes avoidance of the implicated exposure, immunosuppression, and anti-fibrotic therapy in select cases. This narrative review presents the recent literature in the understanding of the immunopathological mechanisms, diagnosis, and treatment of HP.

An updated approach to determine minimal clinically important differences in idiopathic pulmonary fibrosis

Introduction

Current medications for idiopathic pulmonary fibrosis (IPF) have not been shown to impact patient-reported outcome measures (PROMs), highlighting the need for accurate minimal clinically important difference (MCID) values. Recently published consensus standards for MCID studies support using anchor-based over distribution-based methods. The aim of this study was to estimate MCID values for worsening in IPF using only an anchor-based approach.

Methods

We conducted secondary analyses of three randomised controlled trials with different inclusion criteria and follow-up intervals. The health transition question in the 36-Item Short-Form Health Survey (SF-36) questionnaire was used as the anchor. We used receiver operating curves to assess responsiveness between the anchor and 10 variables (four physiological measures and six PROMs). We used an anchor-based method to determine the MCID values of variables that met the responsiveness criteria (area under the curve ≥0.70).

Results

6-min walk distance (6MWD), the St George's Respiratory Questionnaire (SGRQ), physical component score (PCS) of SF-36 and University of California, San Diego, Shortness of Breath Questionnaire (UCSD SOBQ) met the responsiveness criteria. The MCID value for 6MWD was −75 m; the MCID value for SF-36 PCS was −7 points; the MCID value for SGRQ was 11 points; and the MCID value for the UCSD SOBQ was 11 points.

Conclusions

The MCID estimates of 6MWD, SGRQ, SF-36 and UCSD SOBQ using only anchor-based methods were considerably higher compared to previously proposed values. A single MCID value may not be applicable across all classes of disease severity or durations of follow-up time.

Current consensus approaches recommend anchor-based estimation of MCID over distribution-based methods. MCID values of 6MWD, SGRQ, SF-36 and UCSD SOBQ using only anchor-based method were higher than previously reported values.https://bit.ly/37hm0zv

Impact of Gender on the Characteristics of Patients with Idiopathic Pulmonary Fibrosis Included in the RaDiCo-ILD Cohort

BACKGROUND

There is growing evidence of gender-specific phenotypic differences among patients with idiopathic pulmonary fibrosis (IPF), which may affect patient outcomes.

OBJECTIVES

We present the characteristics of patients with IPF at inclusion in the French Rare Disease Cohort - Interstitial Lung Disease (RaDiCo-ILD) with the aim of characterizing gender-specific phenotypic differences.

METHODS

Patients with IPF who were enrolled in the national, multicentre RaDiCo-ILD cohort were included. Demographic characteristics, comorbidities, health-related quality of life (HRQoL) scores, pulmonary function, chest imaging, and IPF treatment were collected at inclusion and described by gender.

RESULTS

The cohort included 724 patients with IPF (54% of RaDiCo-ILD cohort), of whom 82.9% were male. The proportion of male and female patients with a prior history of smoking was 75.0% and 26.8%, respectively. Emphysema was present in 17.0% (95% confidence interval [CI]: 10.0, 24.0) of men and 5.4% (95% CI: 1.2, 9.6) of women. At inclusion, females had poorer HRQoL than males based on St. George's Respiratory Questionnaire scores (48.5 [95% CI: 43.9, 53.0] and 41.5 [39.4, 43.6], respectively). The mean forced vital capacity per cent predicted was 77.7% (95% CI: 76.2, 79.3) and 87.4% (83.4, 91.4) for males and females, respectively. Honeycombing on high-resolution computed tomography (HRCT) was present in 70.8% (95% CI: 61.0, 80.6) of males and 45.8% (95% CI: 35.1, 56.5) of females.

CONCLUSIONS

This analysis of patients with IPF at inclusion in the RaDiCo-ILD cohort provides evidence that comorbid emphysema, lung volume reduction, and honeycombing on HRCT are more common characteristics of males than females.

Serum levels of small HDL particles are negatively correlated with death or lung transplantation in an observational study of idiopathic pulmonary fibrosis

BACKGROUND

Serum lipoproteins, such as high density lipoproteins (HDL), may influence disease severity in idiopathic pulmonary fibrosis (IPF). Here, we investigated associations between serum lipids and lipoproteins and clinical endpoints in IPF.

METHODS

Clinical data and serum lipids were analyzed from a discovery cohort (59 IPF subjects, 56 healthy volunteers) and validated using an independent, multicenter cohort (207 IPF subjects) from the Pulmonary Fibrosis Foundation registry. Associations between lipids and clinical endpoints (FVC, forced vital capacity; 6MWD, 6 min walk distance; GAP (Gender Age Physiology) index; death or lung transplantation) were examined using Pearson's correlation and multivariable analyses.

RESULTS

Serum concentrations of small HDL particles (S-HDLP_NMR), measured by nuclear magnetic resonance (NMR) spectroscopy, correlated negatively with the GAP index in the discovery cohort of IPF subjects. The negative correlation of S-HDLP_NMR with GAP index was confirmed in the validation cohort of IPF subjects. Higher levels of S-HDLP_NMR were associated with lower odds of death or its competing outcome, lung transplantation (OR of 0.9 for each 1 μmol·L^-1 increase in S-HDLP_NMR, p<0.05), at 1, 2, and 3 years from study entry in a combined cohort of all IPF subjects.

CONCLUSIONS

Higher serum levels of S-HDLP_NMR are negatively correlated with the GAP index, as well as with lower observed mortality or lung transplantation in IPF subjects. These findings support the hypothesis that S-HDLP_NMR may modify mortality risk in patients with IPF.

Diagnosis and Evaluation of Hypersensitivity Pneumonitis: CHEST Guideline and Expert Panel Report

BACKGROUND

The purpose of this analysis is to provide evidence-based and consensus-derived guidance for clinicians to improve individual diagnostic decision-making for hypersensitivity pneumonitis (HP) and decrease diagnostic practice variability.

STUDY DESIGN AND METHODS

Approved panelists developed key questions regarding the diagnosis of HP using the PICO (Population, Intervention, Comparator, Outcome) format. MEDLINE (via PubMed) and the Cochrane Library were systematically searched for relevant literature, which was supplemented by manual searches. References were screened for inclusion, and vetted evaluation tools were used to assess the quality of included studies, to extract data, and to grade the level of evidence supporting each recommendation or statement. The quality of the evidence was assessed using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach. Graded recommendations and ungraded consensus-based statements were drafted and voted on using a modified Delphi technique to achieve consensus. A diagnostic algorithm is provided, using supporting data from the recommendations where possible, along with expert consensus to help physicians gauge the probability of HP.

RESULTS

The systematic review of the literature based on 14 PICO questions resulted in 14 key action statements: 12 evidence-based, graded recommendations and 2 ungraded consensus-based statements. All evidence was of very low quality.

INTERPRETATION

Diagnosis of HP should employ a patient-centered approach and include a multidisciplinary assessment that incorporates the environmental and occupational exposure history and CT pattern to establish diagnostic confidence prior to considering BAL and/or lung biopsy. Criteria are presented to facilitate diagnosis of HP. Additional research is needed on the performance characteristics and generalizability of exposure assessment tools and traditional and new diagnostic tests in modifying clinical decision-making for HP, particularly among those with a provisional diagnosis.