Fibroblast activation protein and disease severity, progression, and survival in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive fibrosis in the lungs. Activated fibroblasts play a central role in fibrogenesis and express fibroblast activation protein α. A truncated, soluble form (sFAP) can be measured in blood and is a potential novel biomarker of disease activity. The aim was to study the association between sFAP and clinical, radiological, and histopathological measures of disease severity, progression, and survival in a prospective, multicentre, real-world cohort of patients with IPF. Patients with IPF were recruited from the tertiary interstitial lung disease centres in Denmark and followed for up to 3 years. Baseline serum levels of sFAP were measured by ELISA in patients with IPF and compared to healthy controls. Pulmonary function tests, 6-minute walk test and quality of life measures were performed at baseline and during follow-up. The study included 149 patients with IPF. Median sFAP in IPF was 49.6 ng/mL (IQR: 43.1-61.6 ng/mL) and in healthy controls 73.8 ng/mL (IQR: 62.1-92.0 ng/mL). Continuous sFAP was not associated with disease severity, progression or survival (p > 0.05). After dichotomization of sFAP below or above mean sFAP + 2 SD for healthy controls, higher levels of sFAP were associated with lower FVC % predicted during follow-up (p < 0.01). Higher than normal serum levels of sFAP were associated with longitudinal changes in FVC % predicted, but sFAP did not show clear associations with other baseline or longitudinal parameters. As such, sFAP has limited use as a biomarker of disease progression or survival in patients with IPF.

The fibroblast hormone endotrophin is a biomarker of mortality in chronic diseases.

Fibrosis, driven by fibroblast activities, is an important contributor to morbidity and mortality in most chronic diseases. Endotrophin, a signaling molecule derived from processing of type VI collagen by highly activated fibroblasts, is involved in fibrotic tissue remodeling. Circulating levels of endotrophin have been associated with an increased risk of mortality in multiple chronic diseases. We conducted a systematic literature review collecting evidence from original papers published between 2012 and January 2023 that reported associations between circulating endotrophin (PRO-C6) and mortality. Cohorts with data available to the study authors were included in an Individual Patient Data (IPD) meta-analysis that evaluated the association of PRO-C6 with mortality (PROSPERO registration number: CRD42023340215) after adjustment for age, sex and BMI, where available. In the IPD meta-analysis including sixteen cohorts of patients with different non-communicable chronic diseases (NCCDs) (N=15,205) the estimated summary hazard ratio for 3-years all-cause mortality was 2.10 (95% CI 1.75-2.52) for a 2-fold increase in PRO-C6, with some heterogeneity observed between the studies (I2=70%). This meta-analysis is the first study documenting that fibroblast activities, as quantified by circulating endotrophin, are independently associated with mortality across a broad range of NCCDs. This indicates that, irrespective of disease, interstitial tissue remodeling, and consequently fibroblast activities, has a central role in adverse clinical outcomes, and should be considered with urgency from drug developers as a target to treat.

Identification and management of interstitial lung abnormalities.

Interstitial lung abnormalities (ILA) are incidentally observed specific CT findings in patients without clinical suspicion of interstitial lung disease (ILD). ILA with basal and peripheral predominance and features suggestive of fibrosis in more than 5% of any part of the lung should be referred for pulmonologist review. The strategy for monitoring as described in this review is based on clinical and radiological risk factors. ILA are associated with risk of progression to ILD and increased mortality. Early identification and assessment of risk factors for progression are essential to improve outcome.

Comorbidity and mortality in systemic sclerosis and matched controls: Impact of interstitial lung disease. A population based cohort study based on health registry data.

OBJECTIVE: This population-based, matched cohort study evaluates the impact of comorbidities on mortality among systemic sclerosis (SSc) patients with and without interstitial lung disease (ILD). METHOD: Patients with a first-time SSc diagnosis between 2002 and 2015 were identified in the Danish National Patient Registry, separated into two cohorts - with ILD (SSc-ILD) and without ILD (non-ILD SSc), and matched 1:4 with controls from the general population on age, sex, residency and marital status. Comorbidity and mortality data were obtained from national registries. The Deyo-Charlson comorbidity score (DCcs) was used for assessment of the burden of comorbidities. RESULTS: 1732 patients with SSc and 6919 controls were included; 258 (14.9%) patients had SSc-ILD. The hazard ratio (HR) for death was 2.8 (95% CI 2.4-3.3) in SSc, and especially increased in SSc-ILD (HR 4.2 (95% CI 3.2-5.4)), males (HR 3.1 95% CI 2.4-4.1) and younger adults (aged 18-40 (HR 6.9, 95% CI 3.4-14.2) and 41-50 (HR 7.7, 95% CI 3.8-15.6)). In non-ILD SSc, mortality increased with increasing DCcs. Cancer was the most frequent cause of death in SSc (24.9% of deaths) and in controls (33.5%), in SSc followed by musculoskeletal and connective tissue diseases (22.7%); the cause of only 0.8% of deaths among controls. CONCLUSION: The high prevalence of comorbidities in SSc had extensive impact on mortality. Mortality was increased in males, in young adults and in SSc-ILD, underlining the excess mortality associated with ILD. These findings emphasise the importance of timely diagnosis and optimal management of organ involvement and comorbidities in SSc.

Acute exacerbation of fibrotic interstitial lung diseases.

Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) and other fibrotic interstitial lung diseases (AE-ILD) is defined by significant acute respiratory worsening and new widespread alveolar damage. This review summarises the current knowledge of diagnosis and treatment of these events. The diagnosis of AE-IPF and AE-ILD is based on typical HRCT findings of new and bilateral ground glass opacification and/or consolidation, and exclusion of fluid overload or cardiac failure. Treatment relies, despite low quality of evidence, on glucocorticoid in addition to supportive and palliative treatment. Despite treatment, the prognosis is poor, with a median survival of 2-4 months.

[Pulmonary manifestations in rheumatoid arthritis].

Rheumatoid arthritis (RA) affects more than 30,000 Danes. In this review, we discuss RA in connection with chronic obstructive pulmonary disease (COPD), bronchiectasis and interstitial lung disease (ILD) which are among the most common lung manifestations and are associated with increased mortality. Early suspicion based upon respiratory symptoms should prompt imaging and pulmonary function test. Smoking cessation, vaccination, and rehabilitation are important. COPD and bronchiectasis are treated according to guidelines. Multidisciplinary collaboration in RA-ILD is important and treatment decisions are based on clinical experience and imaging suggesting an inflammatory or fibrotic phenotype.

Impact of reduction in antifibrotic treatment on mortality in idiopathic pulmonary fibrosis.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a severe interstitial lung disease for which two effective antifibrotics, nintedanib and pirfenidone, are available. However, many patients receive a reduced dosage or pause treatment due to side effects although the impact of antifibrotic treatment reduction is uncertain. METHODS: We retrospectively investigated the impact of antifibrotic treatment reduction on death in a large real-life IPF cohort. The primary endpoint of the analyses was time until death by any cause. Five patient groups were defined based on treatment intensity (full, reduced or no treatment) and the antifibrotic drug type (pirfenidone or nintedanib). Between group survival was compared using Cox proportional hazards analysis adjusted for age, sex, smoking status, and lung function at baseline. RESULTS: 375 patients from the Danish PFBIO-cohort were followed from April 2016 until November 2021 with a median follow-up time of 1.84 years. Of patients receiving nintedanib and pirfenidone, 80.19% and 67.42% had reduced treatment, respectively, when considering the entire follow-up period. Treatment with nintedanib and pirfenidone was associated with improved survival compared to no antifibrotic treatment independent of treatment intensity (nintedanib: HR: 0.31, 95%-CI: 0.19-0.53, p < 0.001 & pirfenidone: HR: 0.26, 95%-CI: 0.16-0.42, p < 0.001). Nintedanib and pirfenidone in lower intensities were not associated with worse survival outcomes. CONCLUSION: A substantial proportion of patients with IPF receive reduced antifibrotic treatment to ameliorate the side effects associated with a full dosage regime. Treatment with nintedanib and pirfenidone, independent of treatment intensity, was preferable over no antifibrotic treatment in improving survival and reduced dose appears to be a good alternative if full dose is not tolerated.

Incidence, prevalence and regional distribution of systemic sclerosis and related interstitial lung Disease: A nationwide retrospective cohort study.

OBJECTIVE: To investigate incidence and prevalence of Systemic Sclerosis (SSc) and association with interstitial lung disease (SSc-ILD) in a nationwide population-based study. METHODS: Patients with an incident diagnosis of SSc in 2000-2016 were identified in the Danish National Patient Registry and categorised based on diagnosis of ILD. Incidence- and prevalence proportions were calculated based on the annual population estimates. A cox proportional hazards model was used to evaluate the association between age, sex, region and marital status and presence of ILD. RESULTS: In total, 1869 patients with SSc were identified; 275 patients (14.7%) had SSc-ILD. The majority of patients were females (75.5%). The percentage of males was higher in SSc-ILD than in SSc alone (30.9% and 23.4%, p = 0.008). Median time from SSc to ILD diagnosis was 1.4 years (range 0-14.2). ILD was diagnosed from ≤4 years before to ≥7 years after SSc. Development of ILD was associated with male gender (HR 1.75, 95% CI 1.15-2.66), age 41-50 (HR 1.81, 95% CI 1.07-3.05) and residency in the North Denmark Region (HR 1.95, 9 5% CI 1.12-3.40). Mean annual incidence proportion of SSc was 2.9/100,000 and mean annual prevalence proportion was 16.8/100,000. The incidence remained stable, but prevalence proportion increased from 14.1 - 16.5/100,000 in 2000-2008 to 17.9-19.2/100,000 in 2009-2016. CONCLUSION: The prevalence of SSc increased during the study period, while the incidence remained stable. The prevalence of SSc-ILD was 14.7% and thus less frequent than expected. Male sex and age between 41 and 50 years were associated with ILD.

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.

Antibody responses and risk factors associated with impaired immunological outcomes following two doses of BNT162b2 COVID-19 vaccination in patients with chronic pulmonary diseases.

INTRODUCTION: Responses to COVID-19 vaccination in patients with chronic pulmonary diseases are poorly characterised. We aimed to describe humoral responses following two doses of BNT162b2 mRNA COVID-19 vaccine and identify risk factors for impaired responses. METHODS: Prospective cohort study including adults with chronic pulmonary diseases and healthcare personnel as controls (1:1). Blood was sampled at inclusion, 3 weeks, 2 and 6 months after first vaccination. We reported antibody concentrations as geometric means with 95% CI of receptor binding domain (RBD)-IgG and neutralising antibody index of inhibition of ACE-2/RBD interaction (%). A low responder was defined as neutralising index in the lowest quartile (primary outcome) or RBD-IgG <225 AU/mL plus neutralising index <25% (secondary outcome), measured at 2 months. We tested associations using Poisson regression. RESULTS: We included 593 patients and 593 controls, 75% of all had neutralising index ≥97% at 2 months. For the primary outcome, 34.7% of patients (n=157/453) and 12.9% of controls (n=46/359) were low responders (p<0.0001). For the secondary outcome, 8.6% of patients (n=39/453) and 1.4% of controls (n=5/359) were low responders (p<0.001). Risk factors associated with low responder included increasing age (per decade, adjusted risk ratio (aRR) 1.17, 95% CI 1.03 to 1.32), Charlson Comorbidity Index (per point) (aRR 1.15, 95% CI 1.05 to 1.26), use of prednisolone (aRR 2.08, 95% CI 1.55 to 2.77) and other immunosuppressives (aRR 2.21, 95% CI 1.65 to 2.97). DISCUSSION: Patients with chronic pulmonary diseases established functional humoral responses to vaccination, however lower than controls. Age, comorbidities and immunosuppression were associated with poor immunological responses.

Aspergilloma complicating previous COVID-19 pneumonitis - a case report.

Aspergillomas are found in pre-existing cavities in pulmonary parenchyma. To the best of our knowledge, aspergilloma has not previously been reported in COVID-19-associated pulmonary architecture distortion combined with barotrauma from invasive mechanical ventilation therapy. We present a case of a 67-year-old woman, who suffered from severe COVID-19 in the summer of 2020 with no suspicion of infection with Aspergillus in the acute phase. Ten months after discharge from her COVID-related admission, she developed bilateral aspergillomas diagnosed by image diagnostics, bronchoscopy, and blood samples, and she now receives antifungal therapy. We would like to raise awareness on aspergilloma in post-COVID-19 patients, since it is an expected long-term complication to COVID-19 patients with pulmonary architectural distortion.

Longitudinal serological assessment of type VI collagen turnover is related to progression in a real-world cohort of idiopathic pulmonary fibrosis.

BACKGROUND: Remodeling of the extracellular matrix (ECM) is a central mechanism in the progression of idiopathic pulmonary fibrosis (IPF), and remodeling of type VI collagen has been suggested to be associated with disease progression. Biomarkers that reflect and predict the progression of IPF would provide valuable information for clinicians when treating IPF patients. METHODS: Two serological biomarkers reflecting formation (PRO-C6) and degradation (C6M) of type VI collagen were evaluated in a real-world cohort of 178 newly diagnoses IPF patients. All patients were treatment naïve at the baseline visit. Blood samples and clinical data were collected from baseline, six months, and 12 months visit. The biomarkers were measured by competitive ELISA using monoclonal antibodies. RESULTS: Patients with progressive disease had higher (P = 0.0099) serum levels of PRO-C6 compared to those with stable disease over 12 months with an average difference across all timepoints of 12% (95% CI 3-22), whereas C6M levels tended (P = 0.061) to be higher in patients with progressive disease compared with stable patients over 12 months with an average difference across all timepoints of 12% (95% CI - 0.005-27). Patients who did not receive antifibrotic medicine had a greater increase of C6M (P = 0.043) compared to treated patients from baseline over 12 months with an average difference across all timepoints of 12% (95% CI - 0.07-47). There were no differences in biomarker levels between patients receiving pirfenidone or nintedanib. CONCLUSIONS: Type VI collagen formation was related to progressive disease in patients with IPF in a real-world cohort and antifibrotic therapy seemed to affect the degradation of type VI collagen. Type VI collagen formation and degradation products might be potential biomarkers for disease progression in IPF.

Validation of a derived version of the IPF-specific Saint George's Respiratory Questionnaire.

BACKGROUND: Health-related quality of life (HRQL) is impaired in patients with idiopathic pulmonary fibrosis (IPF). HRQL is often measured using the St. George's Respiratory Questionnaire (SGRQ) despite the development of an IPF-specific version (SGRQ-I). Using data from a real-world cohort of patients with IPF, we aimed to transform SGRQ into a derived version of SGRQ-I, SGRQ-Ider, to examine the cross-sectional and longitudinal validity of SGRQ-Ider and to compare SGRQ-Ider to SGRQ-I. METHODS: Based on results from SGRQ, SGRQ-Ider was derived applying the algorithm used to develop SGRQ-I. Of the 50 items in SGRQ, 34 items were retained in SGRQ-Ider. Response options for seven items were collapsed and minor adjustments were made to the weights of two items after correspondence with the developers of SGRQ-I. Cross-sectional validation, responsiveness and minimal clinically important difference (MCID) were assessed by comparison to other HRQL instruments, pulmonary function tests and 6-min walk test performed at baseline, 6 and 12 months. Furthermore, the association between SGRQ-Ider scores and mortality was examined. RESULTS: A total of 150 IPF patients participated and 124 completed follow-up at 12 months. SGRQ-Ider performed comparably to SGRQ-I with a high concurrent validity, good test-retest reliability and high known-groups validity. SGRQ-Ider was responsive to change in HRQL and physiological anchors. MCID of SGRQ-Ider for improvement and deterioration was 3.5 and 5.7, respectively. SGRQ-Ider scores were associated with mortality in both univariate (HR 1.82, 95% CI 1.42-2.34 per 20-point increase) and multivariate analyses (HR 1.57, 95% CI 1.20-2.05 per 20-point increase). CONCLUSIONS: The SGRQ-Ider is a valid, reliable and responsive HRQL instrument in patients with IPF and has psychometric properties comparable to SGRQ-I. Thus, SGRQ results can reliably be transformed into the SGRQ-Ider. The MCID estimates were calculated for improvement and deterioration separately. Increasing SGRQ-Ider score was associated with increased mortality.

Clusters of comorbidities in idiopathic pulmonary fibrosis.

INTRODUCTION: Comorbidities are common in patients with idiopathic pulmonary fibrosis (IPF) and negatively impact health-related quality of life, health-care costs and mortality. Retrospective studies have focused on individual comorbidities, but clusters of multiple comorbidities have rarely been analysed. This study aimed to comprehensively and prospectively assess comorbidities in a multicentre, real-world cohort of patients with IPF, including prespecified conditions of special interest and to analyse clusters of comorbidities and examine characteristics, disease course and mortality of the clusters. METHODS: Several measurements, questionnaires, medications and medical history were combined to assess comorbidities. Using self-organizing maps, clusters of comorbidities were identified and phenotypes characterized. Disease course was assessed using mixed effects models and mortality using Cox regression. RESULTS: One-hundred and fifty IPF patients were included prospectively. All except one patient suffered from at least one comorbidity and multimorbidity was common. Arterial hypertension, gastro-oesophageal reflux disease, hypercholesterolemia, emphysema and obstructive sleep apnea were most prevalent. Four comorbidity clusters were identified. Each cluster had distinct comorbidity profiles, patient characteristics, symptom burden and disease severity. Patients with fewer comorbidities had better exercise capacity and less dyspnea at baseline, but a trend towards faster deterioration was observed. Mortality analyses showed no significant differences between clusters. CONCLUSIONS: Multimorbidity is prevalent in patients with IPF. Four specific clusters of comorbidities may represent phenotypes in IPF. A trend towards faster decline in exercise capacity and dyspnea was observed in patients with fewer comorbidities. Increased knowledge of comorbidities facilitates prevention and treatment of comorbidities in patients with IPF.

High turnover of types III and VI collagen in progressive idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: Prediction of idiopathic pulmonary fibrosis (IPF) progression is vital for the choice and timing of treatment and patient follow-up. This could potentially be achieved by prognostic blood biomarkers of extracellular matrix (ECM) remodelling. METHODS: Neoepitope biomarkers of types III and VI collagen turnover (C3M, C6M, PRO-C3 and PRO-C6) were measured in 185 patients with newly diagnosed IPF. Disease severity at baseline and progression over 6 months was assessed by lung function tests and 6-min walk tests. All-cause mortality was assessed over a 3-year follow-up period. RESULTS: High baseline levels of C3M, C6M, PRO-C3 and PRO-C6 were associated with more advanced disease at the time of diagnosis. Baseline levels of C6M and PRO-C3 were also associated with mortality over 3 years of follow-up (hazard ratio [HR]: 2.3, 95% CI: 1.3-3.9, p = 0.002 and HR: 1.8, 95% CI: 1.1-3.0, p = 0.03). Patients with several increased biomarkers at baseline, representing a high ECM remodelling phenotype, had more advanced disease at baseline, higher risk of progression or death at 6 months (OR: 1.4, 95% CI: 1.1-1.8, p = 0.002) and higher mortality over 3 years of follow-up (HR: 2.4, 95% CI: 1.3-4.5, p = 0.007). CONCLUSION: Blood biomarkers of types III and VI collagen turnover, assessed at the time of diagnosis, are associated with several indices of disease severity, short-term progression and long-term mortality. These biomarkers can help to identify patients with a high ECM remodelling phenotype at high risk of disease progression and death.

Methotrexate and risk of interstitial lung disease and respiratory failure in rheumatoid arthritis: a nationwide population-based study.

OBJECTIVES: MTX is the most commonly recommended DMARD for first-line treatment of RA, however, it has been hypothesized to cause lung disease as an adverse effect. We investigated the risk of interstitial lung disease (ILD) and acute and chronic respiratory failure in persons with RA treated with MTX and other medications. METHODS: From the Danish National Patient Register (NPR) and the DANBIO register for rheumatic diseases, we retrieved data on 30 512 persons with RA registered in 1997-2015. Information on ILD and respiratory failure was obtained from the NPR. Information on age and sex for all Danish citizens was obtained from the Danish Civil Registration System. MTX and other medication purchases were retrieved from the Danish Prescription Registry. Associations between MTX and lung disease outcomes were analysed in Cox regression models with adjustment for age, calendar time, sex and other medications. Standardized incidence ratios (SIRs) of lung disease were calculated to compare the RA population with the general population. RESULTS: There was no increased risk of lung disease with MTX treatment [one or more purchases compared with no purchases; HR 1.00 (95% CI 0.78, 1.27) for ILD and 0.54 (95% CI 0.43, 0.67) for respiratory failure] at the 5 year follow-up. The SIR was three to four times higher for ILD in MTX-treated persons with RA, but similar to the whole RA population compared with the background population. CONCLUSION: Persons with RA had an increased risk of ILD compared with the general population, but there was no further increased risk associated with MTX treatment.

Proactive prophylaxis with azithromycin and hydroxychloroquine in hospitalized patients with COVID-19 (ProPAC-COVID): a statistical analysis plan.

BACKGROUND: There is an urgent need for treatments that can shorten hospitalization and lower the risk of secondary infection and death in patients with corona disease. The ProPac-COVID trial evaluates whether combination therapy with macrolide azithromycin and hydroxychloroquine via anti-inflammation/immune modulation, antiviral efficacy, and pre-emptive treatment of supra-infections can shorten hospitalization duration and reduce the risk of non-invasive ventilation, treatment in the intensive care unit, and death in patients with acute hospital admission and a positive test for 2019-nCoV and symptoms of COVID-19 disease. METHODS: The ProPAC-COVID is a multi-center, randomized, placebo-controlled, double-blinded clinical trial. The primary outcome is number of days spent alive and out of hospital within 14 days from randomization. Randomization will be in blocks of unknown size, and the final allocation will be stratified for age, site of recruitment, and whether the patient has any chronic lung diseases. Data is analyzed using intention-to-treat (ITT) principles, and main analyses will also be subject to modified ITT analysis and per protocol analysis. DISCUSSION: This paper describes the detailed statistical analysis plan for the evaluation of primary and secondary endpoints of the ProPAC-COVID study. Enrolment of patients to the ProPAC-COVID study is still ongoing. The purpose of this paper is to provide primary publication of study results to prevent selective reporting of outcomes, data-driven analysis, and to increase transparency. TRIAL REGISTRATION: ClinicalTrials.gov NCT04322396 . Registered on 26 March 2020.

Responsiveness and minimal clinically important difference of SGRQ-I and K-BILD in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) specific version of St. George's Respiratory Questionnaire (SGRQ-I) and King's Brief Interstitial Lung Disease questionnaire (K-BILD) are validated health-related quality of life (HRQL) instruments, but no or limited data exist on their responsiveness and minimal clinically important difference (MCID). The objectives of this study were to assess responsiveness of SGRQ-I and K-BILD and determine MCID separately for deterioration and improvement in a large, prospective cohort of patients with IPF in a real-world setting. METHODS: Consecutive patients with IPF were recruited. SGRQ-I, K-BILD, SGRQ, Shortness of Breath Questionnaire, pulmonary function tests and 6-min walk test measurements were obtained at baseline and at six and 12 months; at six and 12 months, patients also completed Global Rating of Change Scales. Responsiveness was assessed using correlation coefficients and linear regression. Cox regression was used for mortality analyses. MCID was estimated using receiver operating characteristic curves with separate analyses for improvement and deterioration. RESULTS: A total of 150 IPF patients were included and 124 completed the 12-month follow-up. Based on all HRQL anchors and most physiological anchors, responsiveness analyses supported the evidence pointing towards SGRQ-I and K-BILD as responsive instruments. Multivariate analyses showed an association between SGRQ-I and mortality (HR: 1.18, 95% CI: 1.02 to 1.36, p = 0.03) and a trend was found for K-BILD (HR: 0.82, 95% CI: 0.64 to 1.05, p = 0.12). MCID was estimated for all domains of SGRQ-I and K-BILD. MCID for improvement differed from deterioration for both SGRQ-I Total (3.9 and 4.9) and K-BILD Total (4.7 and 2.7). CONCLUSIONS: SGRQ-I and K-BILD were responsive to change concerning both HRQL and most physiological anchors. MCID was determined separately for improvement and deterioration, resulting in different estimates; especially a smaller estimate for deterioration compared to improvement in K-BILD. TRIAL REGISTRATION: Clinicaltrials.gov, no. NCT02818712. Registered 30 June 2016.