Use of 6-minute walk distance to predict lung transplant-free survival in fibrosing non-IPF interstitial lung diseases.

BACKGROUND AND OBJECTIVE: The identification of progression in patients with fibrosing non-idiopathic pulmonary fibrosis (IPF) interstitial lung diseases (ILDs) represents an ongoing clinical challenge. Lung function decline alone may have significant limitations in the detection of clinically significant progression. We hypothesized that longitudinal changes of 6-min walk distance (6MWD) from baseline, simultaneously considered with measures of lung function, may independently predict survival and identifying clinically significant progression of disease. METHODS: Forced vital capacity (FVC), diffusing lung capacity (DLCO) and 6MWD were considered both at baseline and at 1 year in a discovery cohort (n = 105) and in a validation cohort (n = 138) from different centres. The primary endpoint was lung transplant (LTx)-free survival. RESULTS: Average follow-up was 3 years in both cohorts. Combined incidence of deaths and LTx was 29% and 21%, respectively. No collinearity and no strong correlations were observed among FVC, DLCO and 6MWD longitudinal changes. While age, gender and BMI were not significant, 6MWD decline ≥24 m predicted LTx-free-survival significantly and independently from FVC and DLCO declines, with high sensitivity and specificity, in both the discovery and the validation cohorts. Although FVC and DLCO declines remained significant predictors of LTx-free survival, 6MWD decline was more accurate than the proposed ATS/ERS/JRS/ALAT functional criteria. Results were confirmed after stratifying patients by baseline FVC. CONCLUSION: Longitudinal declines of 6MWD are associated with poor survival in fibrosing ILDs across a wide range of baseline severity, with high accuracy. 6MWD longitudinal decline is largely independent from lung function decline and may be integrated into the routine assessment of progression.

Percent Predicted vs. Absolute Six-Minute Walk Distance as Predictors of Lung Transplant-Free Survival in Fibrosing Interstitial Lung Diseases.

INTRODUCTION: Fibrosing interstitial lung diseases (ILDs) often progress despite treatment and become life-threatening, with lung transplant (LTx) remaining the only curative option. Six-minute walk distance (6MWD) is increasingly recognized as reliable predictor of clinical course, especially when longitudinally considered. The use of reference equations to express 6MWD as percent predicted (6MWD%) has not been previously studied in fibrosing ILDs. We sought to investigate whether the prognostic power of 6MWD% is superior to that of 6MWD expressed in meters (6MWD-m). METHODS: A retrospective, multicenter cohort analysis was conducted on both idiopathic pulmonary (IPF) and non-IPF fibrosing ILD patients. Patients were divided into a discovery (n = 211) and a validation (n = 260) cohort. Longitudinal changes of 6MWD% and lung function parameters were simultaneously considered. LTx-free survival at 3 years from baseline was the endpoint. Competing risks of death and LTx were considered. RESULTS: Baseline 6MWD% and its longitudinal changes were significant predictors of LTx-free survival and independent from lung function variables. In both cohorts, on multivariate cox proportional hazard regression analysis, receiver operating characteristics analysis and Kaplan-Meier estimates, 6MWD% was consistently, but only slightly superior to 6MWD-m as a predictor of LTx-free survival. CONCLUSION: 6MWD% has only a slight, yet detectable advantage over 6MWD-m as a predictor of survival in fibrosing ILDs. Utilizing 6MWD% may aid in risk stratification, treatment monitoring, and LTx timing optimization. However, available reference equations do have predicting limitations. Refined predictive equations and standardizing reporting practices are therefore needed to further enhance the clinical utility of 6MWD% in fibrosing ILDs.

Progression and prognosis of interstitial pneumonia with autoimmune features: a longitudinal, prospective, multi-centre study.

OBJECTIVES: To evaluate the rate of progression towards specific autoimmune diseases (SADs) of a prospective, multi-centre cohort of patients classifiable as interstitial pneumonia with autoimmune features (IPAF). METHODS: IPAF patients were enrolled based on specific research criteria, and jointly followed by rheumatologists and pulmonologists for at least one year with clinical check-ups, serological exams including autoimmunity, capillaroscopy and high-resolution computed tomography (HRCT). Diagnostic assessment was repeated at least once a year, or earlier when deemed useful. RESULTS: We enrolled 191 IPAF patients through 95 different combinations of IPAF criteria. Of these, 24.1% progressed towards SAD, mainly in connective tissue diseases but also in microscopic polyangiitis. The IPAF patients who progressed were younger than stable IPAF patients (63±10 years vs. 68±9 years, p=0.002) and had a longer follow-up (36.9±18.7 vs. 29.3±15.7 months, p=0.007), but similar severity. No parameters were associated with overall progression, but some parameters were associated with the development of specific diagnoses: Sjögren's syndrome with positivity for SSA (p=0.007, χ2 7.4); idiopathic inflammatory myopathy with mechanic's hands (p=<0.0001, χ2 12.6), organizing pneumonia pattern (p=0.01, χ2 6.1), positivity for anti-Pm/scl (p=0.04 χ2 4.1) and anti-MDA5 (p=0.04, χ2 4.2); systemic sclerosis with palmar telangiectasias (p=<0.0001 2 18.3), positivity for anti-Scl70 (p=<0.0001 χ2 12.5) and anti-PM/Scl (p=0.001 χ2 10.1). CONCLUSIONS: IPAF patients had a rate of progression towards SAD similar to that reported in previous studies on undifferentiated connective tissue diseases, thus including some patients in which lung involvement could represent the first or even the sole clinical manifestation of a SAD.

Sleep-Disordered Breathing and Chronic Respiratory Infections: A Narrative Review in Adult and Pediatric Population.

Sleep-disordered breathing (SDB) comprises different diseases characterized by abnormal respiratory patterns during sleep including obstructive sleep apnea. SDB prevalence and impact in patients with chronic respiratory infections have been only marginally studied. The purpose of this narrative review is to report the prevalence and impact of SDB in chronic respiratory infections, including cystic fibrosis (CF), bronchiectasis and mycobacterial infections, and explore the possible pathophysiological mechanisms. Common pathophysiological mechanisms, underlying SDB onset in all chronic respiratory infections, include inflammation, which plays a central role, chronic nocturnal cough and pain, excessive production of mucous plugs, presence of obstructive and/or restrictive ventilatory impairment, upper airways involvement, and comorbidities, such as alteration of nutritional status. SDB may affect about 50% of patients with bronchiectasis. The severity of the disease, e.g., patients colonized with P. aeruginosa and frequent exacerbators, as well as comorbidities, such as chronic obstructive pulmonary disease and primary ciliary dyskinesia, may impact SDB onset. SDB may also frequently complicate the clinical course of both children and adults with CF, impacting the quality of life and disease prognosis, suggesting that their routine assessment should be incorporated into the clinical evaluation of patients from the first stages of the disease regardless of suggestive symptoms, in order to avoid late diagnosis. Finally, although the prevalence of SDB in patients with mycobacterial infections is uncertain, extrapulmonary manifestations, particularly nasopharyngeal locations, and concomitant symptoms, such as body pain and depression, may act as atypical predisposing factors for their development.

The impact of COVID-19 infection on idiopathic pulmonary fibrosis mortality: a systematic review and meta-analysis.

COVID-19 has a negative impact on the survival of respiratory patients, especially those with interstitial lung disease. This review aims to better understand the effect of COVID-19 on patients with idiopathic pulmonary fibrosis (IPF). A systematic search of MEDLINE, PubMed, Embase, and Scopus performed from December 2019 up to July 2024 identified relevant studies. Eligibility criteria included English language, sample size ≥10 patients, COVID-19 infection and outcome measures. Two independent reviewers assessed studies using the Newcastle-Ottawa Scale for bias and extracted data. Meta-analysis employed a random-effects model, and the Grading of Recommendations Assessment, Development and Evaluation assessed evidence quality. Outcomes considered were hospitalization, intensive care unit admission, and mortality. Of the 1541 initially identified articles, 6 high-quality studies were included. Meta-analysis revealed a 34% mortality rate [95% confidence interval (CI): 21-48%], 36% hospitalization rate (95% CI: 10-75%), and 31% ICU admission rate (95% CI: 7-71%) among IPF patients with COVID-19. The certainty of evidence was low or very low due to publication bias and heterogeneity. This study underscores the elevated risk of hospitalization and death in IPF patients with COVID-19, emphasizing the vulnerability of this population. Prompt and tailored care is crucial to mitigate the impact of COVID-19 on IPF patients, necessitating proactive measures, vaccination, and comprehensive management.

Idiopathic interstitial pneumonia in a patient with von Hippel-Lindau syndrome: a first case.

Although the mechanisms are not known, this is a case of progressive interstitial lung involvement, with a NSIP radiological pattern, evolving in pulmonary fibrosis in a patient with von Hippel-Lindau syndrome, without extrapulmonary fibrosis. https://bit.ly/3QlNStu.