"Can't Stop the Feeling": Symptoms as the Key to Trial Success in Bronchiectasis?

Psychometric Validation and Determination of the Minimal Clinically Important Difference for the Bronchiectasis Health Questionnaire in Adults with Bronchiectasis

Rationale: The Bronchiectasis Health Questionnaire (BHQ) is a concise, self-administered, and disease-specific instrument for measuring health-related quality of life in bronchiectasis. Objectives: We sought to investigate the psychometric properties of a simplified Mandarin BHQ and determine the minimum clinically important difference (MCID) as a reliable clinical endpoint for assessing the efficacy of bronchiectasis treatments. Methods: A longitudinal, randomized controlled trial cohort of 357 patients treated with tobramycin inhalation solution or saline inhalation for Pseudomonas aeruginosa infection and a cross-sectional observational cohort of 436 patients with bronchiectasis were analyzed. Psychometric analyses encompassed convergent validity, known-groups validity, internal consistency, test-retest reliability, and responsiveness. Both anchor-based and distribution-based approaches were utilized to calculate the MCID for therapeutic response. Results: There were significant positive correlations between scores on the BHQ and those on the Quality of Life-Bronchiectasis Respiratory Symptom Scale, with correlation coefficients of 0.698 in the trial cohort and 0.567 in the clinical cohort (both Ps < 0.0001). Known-groups validity indicated significant differences in BHQ scores stratified by baseline Bronchiectasis Severity Index. BHQ scores correlated modestly with both forced expiratory volume in 1 second percent predicted and exacerbation frequency within the previous year. In the trial cohort, the BHQ demonstrated excellent internal consistency (Cronbach's α = 0.893) and test-retest reliability (intraclass correlation coefficient = 0.853). An 8-point improvement in scores on the Quality of Life-Bronchiectasis Respiratory Symptom Scale corresponded to a mean increase of 5.49 points in BHQ scores after 4-week treatment. The MCID for BHQ was consistently 3 points. Conclusions: The BHQ (MCID: 3 points) represents a clinically meaningful tool for evaluating therapeutic intervention outcomes and patient-centered outcomes in patients with bronchiectasis.

Pseudomonas aeruginosa in bronchiectasis: infection, inflammation, and therapies

Introduction: Bronchiectasis is a chronic endobronchial suppurative disease characterized by irreversibly dilated bronchi damaged by repeated polymicrobial infections and predominantly, neutrophilic airway inflammation. Some consider bronchiectasis a syndromic consequence of several different causes whilst others view it as an individual disease entity. In most patients, identifying an underlying cause remains challenging. The acquisition and colonization of affected airways by Pseudomonas aeruginosa represent a critical and adverse clinical consequence for its progression and management.Areas covered: In this review, we outline clinical and pre-clinical peer-reviewed research published in the last 5 years, focusing on the pathogenesis of bronchiectasis and the role of P. aeruginosa and its virulence in shaping host inflammatory and immune responses in the airway. We further detail its role in airway infection, the lung microbiome, and address therapeutic options in bronchiectasis.Expert opinion: P. aeruginosa represents a key pulmonary pathogen in bronchiectasis that causes acute and/or chronic airway infection. Eradication can prevent adverse clinical consequence and/or disease progression. Novel therapeutic strategies are emerging and include combination-based approaches. Addressing airway infection caused by P. aeruginosa in bronchiectasis is necessary to prevent airway damage, loss of lung function and exacerbations, all of which contribute to adverse clinical outcome.

A high-risk airway mycobiome is associated with frequent exacerbation and mortality in COPD

INTRODUCTION

The chronic obstructive pulmonary disease (COPD) bacteriome associates with disease severity, exacerbations and mortality. While COPD patients are susceptible to fungal sensitisation, the role of the fungal mycobiome remains uncertain.

METHODS

We report the largest multicentre evaluation of the COPD airway mycobiome to date, including participants from Asia (Singapore and Malaysia) and the UK (Scotland) when stable (n=337) and during exacerbations (n=66) as well as nondiseased (healthy) controls (n=47). Longitudinal mycobiome analysis was performed during and following COPD exacerbations (n=34), and examined in terms of exacerbation frequency, 2-year mortality and occurrence of serum specific IgE (sIgE) against selected fungi.

RESULTS

A distinct mycobiome profile is observed in COPD compared with controls as evidenced by increased α-diversity (Shannon index; p<0.001). Significant airway mycobiome differences, including greater interfungal interaction (by co-occurrence), characterise very frequent COPD exacerbators (three or more exacerbations per year) (permutational multivariate ANOVA; adjusted p<0.001). Longitudinal analyses during exacerbations and following treatment with antibiotics and corticosteroids did not reveal any significant change in airway mycobiome profile. Unsupervised clustering resulted in two clinically distinct COPD groups: one with increased symptoms (COPD Assessment Test score) and Saccharomyces dominance, and another with very frequent exacerbations and higher mortality characterised by Aspergillus, Curvularia and Penicillium with a concomitant increase in serum sIgE levels against the same fungi. During acute exacerbations of COPD, lower fungal diversity associates with higher 2-year mortality.

CONCLUSION

The airway mycobiome in COPD is characterised by specific fungal genera associated with exacerbations and increased mortality.