Prognostic Value of Frequent Exacerbations in Bronchiectasis: The Relationship With Disease Severity

The characteristics and prognosis of bronchiectasis patients with airflow limitation: a prospective longitudinal study

BACKGROUND

As bronchiectasis progresses, increasing degrees of airflow limitation can occur.

OBJECTIVES

This study aimed to investigate whether concomitant airflow limitation was associated with poor prognosis in patients with bronchiectasis and to identify the characteristics of patients with airflow limitation in bronchiectasis.

DESIGN

A prospective longitudinal study was conducted to determine the characteristics and prognosis of bronchiectasis patients with airflow limitation.

METHODS

We conducted a prospective longitudinal study. Patients who failed to complete the follow-up were withdrawn from the trial. High-resolution computed tomography (HRCT) was used for diagnosing bronchiectasis, whereas postbronchodilator forced expiratory volume in one second of the predicted value (post-FEV1%) was employed for grading airflow limitation. The main variables included questionnaires, anthropometric measurements, pulmonary function tests, laboratory tests, and CT findings. The primary outcome was frequent exacerbations. Differences among the groups were evaluated via two-tailed Student's t test or ANOVA for continuous variables if the data were normally distributed. In the case of a nonnormal distribution, the Mann-Whitney U test and Kruskal-Wallis test were used. The chi-square test or Fisher's exact test was used for categorical variables. Binary logistic regression analyses were used to identify factors and calculate the odds ratio (OR) for frequent exacerbations.

RESULTS

A total of 189 subjects with bronchiectasis were enrolled in the study, including 97 patients with airflow limitation and 92 patients without airway obstruction. Patients with airflow limitation had greater numbers of exacerbations (1.46 ± 0.83 vs. 1.76 ± 1.10 times, P = 0.013) at 12 months after enrolment and greater numbers of hospitalizations (1.10 ± 0.30 vs. 1.36 ± 0.67 times, P = 0.0016) at 24 months after enrolment. In addition, acute exacerbations lasted longer (8.69 ± 3.78 vs. 13.11 ± 14.03 days, P = 0.0171), and the total number of hospitalizations was greater (1.34 ± 0.77 vs. 1.80 ± 1.67 times, P = 0.0421) for patients with a mean follow-up duration of 32 months (Table 3). Bronchiectasis patients with airflow limitation exhibit more severe manifestations of bronchiectasis both clinically and functionally. Furthermore, the cohort of bronchiectasis patients with airflow limitation had a significantly greater infection rate than did the BE group (P = 0.0244), with a notable disparity observed in the incidence of P. aeruginosa infection (P < 0.0001).

CONCLUSION

The results of our study suggest that patients with airflow limitation are more likely to experience acute exacerbations and hospitalizations than are those without airflow limitation. Patients with bronchiectasis concomitant with airflow limitation should be identified as early as possible, and individualized treatment methods should be formulated.

[Management of adult bronchiectasis - Consensus-based Guidelines for the German Respiratory Society (DGP) e. V. (AWMF registration number 020-030)]

Bronchiectasis is an etiologically heterogeneous, chronic, and often progressive respiratory disease characterized by irreversible bronchial dilation. It is frequently associated with significant symptom burden, multiple complications, and reduced quality of life. For several years, there has been a marked global increase in the prevalence of bronchiectasis, which is linked to a substantial economic burden on healthcare systems. This consensus-based guideline is the first German-language guideline addressing the management of bronchiectasis in adults. The guideline emphasizes the importance of thoracic imaging using CT for diagnosis and differentiation of bronchiectasis and highlights the significance of etiology in determining treatment approaches. Both non-drug and drug treatments are comprehensively covered. Non-pharmacological measures include smoking cessation, physiotherapy, physical training, rehabilitation, non-invasive ventilation, thoracic surgery, and lung transplantation. Pharmacological treatments focus on the long-term use of mucolytics, bronchodilators, anti-inflammatory medications, and antibiotics. Additionally, the guideline covers the challenges and strategies for managing upper airway involvement, comorbidities, and exacerbations, as well as socio-medical aspects and disability rights. The importance of patient education and self-management is also emphasized. Finally, the guideline addresses special life stages such as transition, family planning, pregnancy and parenthood, and palliative care. The aim is to ensure comprehensive, consensus-based, and patient-centered care, taking into account individual risks and needs.

Modulator-refractory cystic fibrosis: Defining the scope and challenges of an emerging at-risk population

Cystic fibrosis (CF) causes life-shortening respiratory and systemic disease due to dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. Highly effective modulator therapies (HEMT) improve the lives of many people with cystic fibrosis (PwCF) by correcting the structure and function of the defective CFTR channel at the molecular level. Despite these advancements, a subset of patients-termed modulator-refractory CF-continues to experience two or more pulmonary exacerbations per year requiring hospitalization or intravenous antibiotics, regardless of other modulator benefits. This underrecognized group represents an emerging challenge within the CF community. We discuss the benefits and limitations of current CFTR modulator therapies and the urgent need to investigate this emerging at-risk population. While HEMT improves lung function, decreases exacerbations, reduces the need for lung transplantation, and lowers mortality, increasing evidence shows that not all patients benefit equally. At the University of Virginia, nearly 6% of adults with CF exhibit the modulator-refractory phenotype. The driving factors of modulator-refractory CF are likely multifactorial, including genetic variations, variable immune responses, preexisting bronchiectasis, microbiological colonization, preexisting comorbid conditions, and environmental and socioeconomic factors. This perspective review recognizes and defines modulator-refractory CF as a distinct emerging clinical phenotype in the post-modulator era. Understanding this phenotype is crucial for reducing morbidity and mortality, and for improving the quality of life for PwCF. Raising awareness of modulator-refractory CF will help the community address this population and perform further research to identify causes. The emergence of modulator-refractory CF highlights a significant gap in our current treatment landscape and provides an opportunity to develop innovative therapeutic strategies that may benefit the entire CF community, ensuring that no person with CF is left behind.

Artificial Intelligence-based CT Assessment of Bronchiectasis: The COPDGene Study

Background CT is the standard method used to assess bronchiectasis. A higher airway-to-artery diameter ratio (AAR) is typically used to identify enlarged bronchi and bronchiectasis; however, current imaging methods are limited in assessing the extent of this metric in CT scans. Purpose To determine the extent of AARs using an artificial intelligence-based chest CT and assess the association of AARs with exacerbations over time. Materials and Methods In a secondary analysis of ever-smokers from the prospective, observational, multicenter COPDGene study, AARs were quantified using an artificial intelligence tool. The percentage of airways with AAR greater than 1 (a measure of airway dilatation) in each participant on chest CT scans was determined. Pulmonary exacerbations were prospectively determined through biannual follow-up (from July 2009 to September 2021). Multivariable zero-inflated regression models were used to assess the association between the percentage of airways with AAR greater than 1 and the total number of pulmonary exacerbations over follow-up. Covariates included demographics, lung function, and conventional CT parameters. Results Among 4192 participants (median age, 59 years; IQR, 52-67 years; 1878 men [45%]), 1834 had chronic obstructive pulmonary disease (COPD). During a 10-year follow-up and in adjusted models, the percentage of airways with AARs greater than 1 (quartile 4 vs 1) was associated with a higher total number of exacerbations (risk ratio [RR], 1.08; 95% CI: 1.02, 1.15; P = .01). In participants meeting clinical and imaging criteria of bronchiectasis (ie, clinical manifestations with ≥3% of AARs >1) versus those who did not, the RR was 1.37 (95% CI: 1.31, 1.43; P < .001). Among participants with COPD, the corresponding RRs were 1.10 (95% CI: 1.02, 1.18; P = .02) and 1.32 (95% CI: 1.26, 1.39; P < .001), respectively. Conclusion In ever-smokers with chronic obstructive pulmonary disease, artificial intelligence-based CT measures of bronchiectasis were associated with more exacerbations over time. Clinical trial registration no. NCT00608764 © RSNA, 2022 Supplemental material is available for this article. See also the editorial by Schiebler and Seo in this issue.