European Respiratory Journal最新文献

Background: There is a pressing need to identify early biomarkers of lung involvement in systemic sclerosis (SSc) to start as soon as possible antifibrotic therapy. We aimed to identify extracellular vesicle-derived microRNAs (EV-miRNAs) that are differentially expressed between SSc patients with and without interstitial lung disease (ILD), explore their diagnostic value and investigate their functional properties.

Methods: Small EVs (sEVs) derived from plasma were isolated from 91 well-characterised SSc patients with ILD (SSc-ILD, n=45), without ILD (SSc-no ILD, n=46) and 43 matched healthy subjects (HS). Small RNA sequencing followed by quantitative RT-PCR were used to identify and validate sEV-miRNAs associated to SSc-ILD. Correlations between SSc-ILD-associated miRNAs and clinical parameters were assessed, as well as the impact of related miRNAs/sEVs on fibrosis.

Results: We identified a 4-miRNA signature associated with ILD in SSc context (miR-584-5p, miR-744-5p, miR-1307-3p and miR-10b-5p) (ROC AUC=0.85, 95% CI 0.76-0.94, p<0.0001). Deeper analysis revealed a correlation of these candidates with pulmonary function tests (DLCO and FVC), highlighting their capacity to monitor lung fibrosis progression in SSc patients. Furthermore, SSc-ILD-associated sEV miRNAs are positively correlated and enriched in circulating lymphocytes, suggesting that these immune cells are their cellular source. Finally, functional studies highlighted an alteration of functional properties of sEVs in SSc-ILD context mainly due to the transfer of profibrotic miR-584-5p in lung fibroblasts.

Conclusions: Our sEV-based biomarker approach enabled to identify a promising 4-miRNA signature characteristic of ILD in SSc patients. Furthermore, the profibrotic properties of SSc-ILD-associated sEVs suggest a prominent role of these vesicles on SSc severity.

Background: Exercise pulmonary hypertension, defined as a mean pulmonary arterial pressure (mPAP)/cardiac output (Q̇c) slope >3 WU during exercise, is common in patients with heart failure with preserved ejection fraction (HFpEF). However, the pulmonary gas exchange-related effects of an exaggerated exercise pulmonary hypertension (EePH) response are not well defined, especially in relation to dyspnoea on exertion and exercise intolerance.

Methods: 48 HFpEF patients underwent invasive (pulmonary and radial artery catheters) constant-load (20 W) and maximal incremental cycle testing. Haemodynamic measurements (mPAP and Q̇c), arterial blood and expired gases, and ratings of perceived breathlessness (Borg 0-10 scale) were obtained. The mPAP/Q̇c slope was calculated from rest to 20 W. Those with a mPAP/Q̇c slope ≥4.2 (median) were classified as HFpEF+EePH (n=24) and those with a mPAP/Q̇c slope <4.2 were classified as HFpEF (without EePH) (n=24). The alveolar-arterial oxygen tension difference, dead space to tidal volume ratio (Bohr equation) and the minute ventilation to carbon dioxide production slope (from rest to 20 W) were calculated.

Results: Arterial oxygen tension was lower (p=0.03) and dead space to tidal volume ratio was higher (p=0.03) at peak exercise in HFpEF+EePH than in HFpEF. The alveolar-arterial oxygen tension difference was similar at peak exercise between groups (p=0.14); however, patients with HFpEF+EePH achieved the peak alveolar-arterial oxygen tension difference at a lower peak work rate (p<0.01). The minute ventilation to carbon dioxide production slope was higher in HFpEF+EePH than in HFpEF (p=0.01). Perceived breathlessness was ≥1 unit higher at 20 W and peak oxygen uptake was lower (p<0.01) in HFpEF+EePH than in HFpEF.

Conclusions: These data suggest that EePH contributes to pulmonary gas exchange impairments during exercise by causing a ventilation/perfusion mismatch that provokes both ventilatory inefficiency and hypoxaemia, both of which seem to contribute to dyspnoea on exertion and exercise intolerance in patients with HFpEF.

Background: Interstitial lung disease is rarer in children than adults, but, with increasing diagnostic awareness, more cases are being discovered. The prognosis of childhood interstitial lung disease is often poor, but increasing numbers are now surviving into adulthood.

Aim: To characterise childhood interstitial lung disease survivors and identify their impact on adult interstitial lung disease centres.

Methods: This was a European study (34 adult and childhood interstitial lung disease centres) reporting incident/prevalent cases of childhood interstitial lung disease survivors from January to July 2023. Epidemiological, clinical, physiological and genetic data were collected.

Results: 244 patients were identified with a median (interquartile range) age at diagnosis of 12.5 years (6-16 years) and age at study inclusion of 25 years (22-33 years), with 51% male, 86% nonsmokers and a median (interquartile range) % predicted forced vital capacity of 70% (47-89%) and diffusing capacity of the lungs for carbon monoxide of 48% (32-75%). 32% were prescribed long-term oxygen and 227 (93%) were followed up in adult centres whereas 17 (7%) never transitioned. The commonest diagnoses (82%) were childhood interstitial lung disease category B1 (sarcoidosis, hemosiderosis, connective tissue disorders, vasculitis) at 35%, A4 (surfactant-related) at 21%, B2 (bronchiolitis obliterans, hypersensitivity pneumonitis) at 14% and Bz (unclassified interstitial lung disease) at 13%. Bz patients had the worst functional status. 60% of all patients were still being prescribed corticosteroids. Re-specification of diagnosis and treatment were made after transition for 9.8% and 16% of patients, respectively. Not all childhood interstitial lung disease diagnoses were recognised in adult interstitial lung disease classifications.

Conclusion: Childhood interstitial lung disease survivors are seen in most adult interstitial lung disease centres and only a minority continue follow-up in paediatric centres. Survivors have a significant loss of lung function. The heterogeneity of their aetiologies and therapeutic requirements has a real impact on adult interstitial lung disease centres. Re-specification of diagnosis and treatment may contribute to precision and personalisation of management.

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) report states that the diagnosis of COPD should be considered in individuals with chronic respiratory symptoms and/or exposure to risk factors. Forced spirometry demonstrating airflow obstruction after bronchodilation is required to confirm the diagnosis using a threshold of forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratio <0.7. This GOLD Science Committee review weighs the evidence for using pre- or post-bronchodilator (BD) spirometry to diagnose COPD. Cohort studies have shown that pre- and post-BD spirometry give concordant diagnostic results in most cases, although the prevalence of COPD is up to 36% lower with post-BD values. Discordant results may occur in "volume" or "flow" responders. Volume responders have reduced FVC due to gas trapping causing FEV₁/FVC ≥0.7 pre-BD, but a volume response occurs post-BD with a greater improvement in FVC relative to FEV₁ decreasing the ratio to <0.7. Flow responders show a greater FEV₁ improvement relative to FVC which may increase FEV₁/FVC from <0.7 pre-BD to ≥0.7 post-BD; these individuals have an increased likelihood of developing post-BD obstruction during follow-up and require monitoring longitudinally. GOLD 2025 recommends using pre-BD spirometry to rule out COPD and post-BD measurements to confirm the diagnosis. This will reduce clinical workload. Post-BD results close to the threshold should be repeated to ensure a correct diagnosis is made. Post-BD measurements ensure that volume responders are not overlooked and limit COPD overdiagnosis.