Abnormal Exertional Breathlessness on Cardiopulmonary Cycle Exercise Testing in Relation to Self-Reported and Physiologic Responses in Chronic Airflow Limitation.

BACKGROUND: Exertional breathlessness is a cardinal symptom of cardiorespiratory disease. RESEARCH QUESTION: How does breathlessness abnormality, graded using normative reference equations during cardiopulmonary exercise testing (CPET), relate to self-reported and physiologic responses in people with chronic airflow limitation (CAL)? STUDY DESIGN AND METHODS: An analysis was done of people aged ≥ 40 years with CAL undergoing CPET in the Canadian Cohort Obstructive Lung Disease study. Breathlessness intensity ratings (Borg CR10 scale [0-10 category-ratio scale for breathlessness intensity rating]) were evaluated in relation to power output, rate of oxygen uptake, and minute ventilation at peak exercise, using normative reference equations as follows: (1) probability of breathlessness normality (probability of having an equal or greater Borg CR10 rating among healthy people; lower probability reflecting more severe breathlessness) and (2) presence of abnormal breathlessness (rating above the upper limit of normal). Associations with relevant participant-reported and physiologic outcomes were evaluated. RESULTS: We included 330 participants (44% women): mean ± SD age, 64 ± 10 years (range, 40-89 years); FEV1/FVC, 57.3% ± 8.2%; FEV1, 75.6% ± 17.9% predicted. Abnormally low exercise capacity (peak rate of oxygen uptake < lower limit of normal) was present in 26%. Relative to peak power output, rate of oxygen uptake, and minute ventilation, abnormally high breathlessness was present in 26%, 25%, and 18% of participants. For all equations, abnormally high exertional breathlessness was associated with worse lung function, exercise capacity, self-reported symptom burden, physical activity, and health-related quality of life; and greater physiologic abnormalities during CPET. INTERPRETATION: Abnormal breathlessness graded using CPET normative reference equations was associated with worse clinical, physiological, and functional outcomes in people with CAL, supporting construct validity of abnormal exertional breathlessness.

Biological Anti-IL-5/IL-5R Therapeutics for Chronic Obstructive Pulmonary Disease (COPD) with Specific Treatable Traits: A Real-World Retrospective Analysis.

Introduction: We describe the use of anti-IL-5 monoclonal antibodies from a COPD clinic, a source other than traditional clinical trials. The objectives were to characterize the patient subgroup prescribed anti-IL-5 monoclonal antibodies and to report potential benefits. Methods: This is a retrospective case series study of 17 patients treated in a COPD subspecialty clinic. All patients had a diagnosis of COPD (post-bronchodilator FEV1/FVC <0.7) and had been prescribed an anti-IL-5 biologic for at least 8 months. Acute exacerbations of COPD (AECOPDs) were collected as reported in electronic medical records. Results: All patients (17) enrolled were treated with biologics for ≥8 months, and 13 (76%) for ≥1 year. Patients were characterized by severe disease traits, FEV1 <50% predicted, recurrent exacerbations (3.5 moderate-to-severe AECOPDs in the year before treatment), high peripheral blood eosinophil counts (≥250 cells/µL in the previous year), all on inhaled triple therapy, and only 1 patient with a diagnosis of asthma prior to smoking. There was a statistically significant decrease in the exacerbation rate compared with baseline after 8 and 12 months of anti-IL-5 treatment, respectively, yielding the equivalent of a 2-3x reduction in exacerbation rate. Absolute FEV1 decreased, and the decline in FEV1 % of predicted reached statistical significance (p<0.05); CAT score improved (p<0.05). Discussion: This real-world evidence data aligns with existing studies suggesting the potential benefit of anti-IL-5 treatment for specific patients with COPD and therefore advocates for further investigation of RCTs on the use of anti-IL-5 biologics for well-characterized patients with COPD.

Single-Cell Sequencing Reveals MYOF-Enriched Monocyte/Macrophage Subcluster as a Favorable Prognostic Factor in Sepsis.

This research utilized single-cell RNA sequencing to map the immune cell landscape in sepsis, revealing 28 distinct cell clusters and categorizing them into nine major types. Delving into the monocyte/macrophage subclusters, 12 unique subclusters are identified and pathway enrichment analyses are conducted using KEGG and GO, discovering enriched pathways such as oxidative phosphorylation and antigen processing. Further GSVA and AUCell assessments show varied activation of interferon pathways, especially in subclusters 4 and 11. The clinical correlation analysis reveals genes significantly linked to survival outcomes. Additionally, cellular differentiation in these subclusters is explored. Building on these insights, the differential gene expression within these subclusters is specifically scrutinized, which reveal MYOF as a key gene with elevated expression levels in the survivor group. This finding is further supported by in-depth pathway enrichment analysis and the examination of cellular differentiation trajectories, where MYOF's role became evident in the context of immune response regulation and sepsis progression. Validating the role of the MYOF gene in sepsis, a dose-dependent response to LPS in THP-1 cells and C57 mice is observed. Finally, inter-cellular communications are analyzed, particularly focusing on the MYOF+Mono/Macro subcluster, which indicates a pivotal role in immune regulation and potential therapeutic targeting.