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Article

Clinical Impacts of Pseudomonas aeruginosa Isolation in Patients with Bronchiectasis: Findings from KMBARC Registry

1
Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Veterans Health Service Medical Center, Seoul 05368, Republic of Korea
2
Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, National Medical Center, Seoul 04564, Republic of Korea
3
Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
*
Authors to whom correspondence should be addressed.
These authors contributed equally to this work as co-first authors.
J. Clin. Med. 2024, 13(17), 5011; https://doi.org/10.3390/jcm13175011
Submission received: 11 July 2024 / Revised: 17 August 2024 / Accepted: 22 August 2024 / Published: 24 August 2024
(This article belongs to the Special Issue Adult Lung Disease: Clinical Symptoms, Diagnosis, and Treatment)

Abstract

:
Background: Pseudomonas aeruginosa isolation in bronchiectasis is associated with a poor prognosis, including increased hospital admissions, exacerbation, and mortality. In this study, we aimed to evaluate the clinical characteristics and outcomes of P. aeruginosa isolation from patients with bronchiectasis in South Korea. Methods: This multicenter prospective cohort study analyzed 936 patients with bronchiectasis. We examined the prevalence of P. aeruginosa isolates and other microbiological characteristics. Additionally, the clinical characteristics related to disease severity and 1-year prognosis were compared between patients with and without P. aeruginosa isolation. Propensity score matching was used to mitigate confounding biases. Results: Of the 936 patients with bronchiectasis, P. aeruginosa was isolated from 89. A total of 445 matched patients—356 patients without (non-Pseudomonas group) and 89 with (Pseudomonas group) P. aeruginosa isolation—were analyzed. The Pseudomonas group showed poorer lung function, greater involvement of radiographic bronchiectasis, and a higher proportion of cystic bronchiectasis than the non-Pseudomonas group. After one year, more patients in the Pseudomonas group were admitted for bronchiectasis than in the non-Pseudomonas group. Moreover, the Bronchiectasis Health Questionnaire scores were significantly lower in the Pseudomonas group than in the non-Pseudomonas group. Conclusions: The isolation of P. aeruginosa was independently associated with increased disease severity and poor clinical outcomes in Korean patients with bronchiectasis.

Graphical Abstract

1. Introduction

Non-cystic fibrosis bronchiectasis (henceforth referred to as bronchiectasis) poses a significant medical challenge owing to its chronic and progressive nature. Bronchiectasis significantly impairs patient quality of life and imposes a substantial disease burden due to recurrent exacerbations and infections [1]. Despite its prevalence, bronchiectasis is often overlooked, likely due to the uncertainty regarding its treatment and etiology [2].
Amidst the uncertainty regarding bronchiectasis, one clear fact has emerged: Pseudomonas aeruginosa is the most important pathogenic agent [3,4]. Playing a pivotal role in pathogenesis and prognosis, P. aeruginosa activates inflammation and promotes tissue damage in the airways through the secretion of proteins and cellular components, which is a crucial mechanism in bronchiectasis development [5,6]. Recognized as a key prognostic factor, its colonization in patients with bronchiectasis is associated with adverse clinical outcomes, including frequent pulmonary infections, hospital admissions, declining pulmonary function, and high mortality rates [7,8,9,10]. Microbiome research supports these findings, highlighting the impact of P. aeruginosa-dominated microbiomes on lung function decline and frequent exacerbations compared with those associated with other microbiome profiles [11].
The incidence of P. aeruginosa colonization in bronchiectasis varies across geographical regions and ethnic populations, ranging from 9% to 33% [9,12,13]. Although studies in Asian countries report an incidence of 25–30%, there is limited information on P. aeruginosa colonization in bronchiectasis in South Korea. In addition, few studies have explored the clinical implications of P. aeruginosa colonization, owing to the lack of large bronchiectasis cohorts. This study aimed to address this gap by investigating the incidence and clinical impact of P. aeruginosa colonization in patients with bronchiectasis in South Korea.

2. Materials and Methods

2.1. Study Population

We analyzed the data from the Korean Multicenter Bronchiectasis Audit and Research Collaboration (KMBARC) registry [14,15]. The KMBARC registry is a prospective cohort study conducted across more than 26 centers in South Korea. Participants were enrolled from August 2018 to April 2021 (trial No. KCT 0003088). KMBARC adhered to the protocol of the European Multicenter Bronchiectasis Audit and Research Collaboration (EMBARC) [16] to gather clinical information from patients with bronchiectasis in South Korea. The data collected included bronchiectasis health questionnaires [17], assessments of fatigue and depression assessments, blood test results, exacerbation definitions, and details of emergency room or hospital visits.
The inclusion criteria for this study were as follows: (1) patients aged 18 years or older with or without respiratory symptoms (cough, sputum, or respiratory infection) and bronchiectasis involving one or more lobes confirmed by chest computed tomography; (2) patients hospitalized for respiratory disease in a stable condition at the time of enrollment and at least 4 weeks post-discharge. The exclusion criteria were as follows: (1) cystic fibrosis; (2) traction bronchiectasis observed in interstitial lung disease; (3) active treatment for pneumonia, pulmonary tuberculosis (TB), or non-tuberculous mycobacterial pulmonary disease; (4) inability or unwillingness to provide informed consent; (5) pregnancy. Informed consent was obtained from all the participants. The Institutional Review Board of the National Medical Center of Korea approved the study design (IRB no. H-1807-092-015).

2.2. Data Collection

Epidemiological data, including age, sex, body mass index (BMI), number of bronchiectasis diagnoses, smoking history, total smoking history, and comorbidities (chronic obstructive pulmonary disease [COPD], asthma, history of TB, rhinosinusitis, cardiovascular disease, pulmonary hypertension, stroke, diabetes mellitus, osteoporosis, chronic kidney disease, malignancy, depression, and anxiety) were examined. Clinical details included radiographic involvement; medication history, including the use of inhalers and oral antibiotics; microbiology and source of sputum; pulmonary function tests; Modified Medical Research Council (mMRC) dyspnea scale; sputum volume; presence of hemoptysis; exacerbations; hospitalization within the previous year of enrollment. Indicators of clinical severity included the Bronchiectasis Health Questionnaire (BHQ), bronchiectasis severity index (BSI) [18], FACED score (forced expiratory volume in 1 s (FEV1), age, chronic colonization by Pseudomonas aeruginosa, radiological extension, and dyspnea) [19]. The clinical and epidemiological characteristics of the patients enrolled in the KMBARC registry were reported by Lee et al. [15].

2.3. Definition of Terminology and Outcomes

The etiology of bronchiectasis was determined by the attending pulmonologist through interviews and clinical assessment of the patient.
Exacerbation of bronchiectasis was defined according to the international consensus [20] and characterized by a deterioration of three or more of the following six symptoms that persisted for 48 h or more and improved with treatment: (1) coughing, (2) sputum volume and/or consistency, (3) sputum purulence, (4) dyspnea and/or exercise tolerance, (5) fatigue and/or malaise, and (6) hemoptysis.
Pseudomonas colonization was defined as the identification of Pseudomonas in at least two separate sputum culture studies with the following criteria: (1) Pseudomonas was isolated from a sputum sample obtained during stable status, with a history of Pseudomonas isolation; (2) Pseudomonas was isolated from the sputum culture at enrollment and at the 1-year follow-up sputum culture; (3) a history of Pseudomonas isolation and Pseudomonas was isolated in the 1-year follow-up sputum culture.
The primary outcome was the occurrence of exacerbations at a 1-year follow-up. Secondary outcomes included hospitalization for bronchiectasis, hemoptysis requiring hospitalization, antibiotic use, changes in clinical severity indices (BHQ, BSI, and FACED scores), and changes in lung function at a 1-year follow-up.

2.4. Statistical Analysis

For patients colonized with Pseudomonas, propensity score matching was conducted by adjusting for age and sex at a ratio of 1:4 in the control group. The MatchIt package in R was used for analysis.
Categorical variables were compared using the chi-square or Fisher’s exact test, and continuous functions were compared using Student’s t-test or Wilcoxon rank-sum analysis. Logistic and negative binomial regression analyses were performed to assess the risks of hemoptysis, exacerbation, and hospital admission during the 1-year follow-up period. Multivariate regression analyses were adjusted for age, sex, and BMI. R software (version 4.3.1; The R Foundation for Computing, Vienna, Austria) and STATA (version 17; StataCorp, College Station, TX, USA) were used for statistical analyses.

3. Results

3.1. Baseline Characteristics of the Population

Of the 936 patients enrolled in KMBARC, 89 with Pseudomonas colonization were identified (Figure 1). The mean age of the total population was 64.4 ± 9.4 years (Table 1). The duration of bronchiectasis was significantly longer in the Pseudomonas colonization group than in the non-colonization group (with mean ± standard deviation in years of 3.7 ± 1.7 vs. 3.2 ± 1.6, p = 0.006). Additionally, the proportion of patients with COPD was significantly higher in the Pseudomonas group (43.8% vs. 32.0%; p = 0.036) (Table 1). Radiologic extension of bronchiectasis was greater in the Pseudomonas group, affecting more lobes on average (2.7 ± 1.5 vs. 2.3 ± 1.6, p = 0.021), particularly the lingula and the left lower lobe (Table 1).
Of the 325 patients who provided samples at stable status, microorganisms were isolated from 151 (46.5%) samples. P. aeruginosa was the most frequently isolated microorganism, found in 92/151 (60.9%) of the positive cultures (Table 2). Other less commonly isolated organisms included Streptococcus viridans (13.3%), Staphylococcus aureus (6.6%), Klebsiella pneumoniae (6.0%), Hemophilus influenza (4.6%), Escherichia coli (4.6%), Enterobacter cloacae (2.7%), Streptococcus pneumonia (2.0%), and Moraxella catarrhalis (1.3%) (Table 2).

3.2. Clinical Characteristics Related to Bronchiectasis

The Pseudomonas group had significantly poorer lung function across all measures related to bronchiectasis than the non-Pseudomonas group, with lower pre- and post-bronchodilator forced expiratory volume in one second (FEV1) and FVC both in absolute terms and as a percentage of the predicted values (p < 0.001) (Table 3). However, there was no significant difference in the respiratory symptoms or acute exacerbation history between the two groups. The Pseudomonas group had a higher FACED score (3.1 ± 1.5 vs. 1.9 ± 1.6) and BSI score (10.5 ± 3.4 vs. 6.6 ± 3.6), indicating more severe disease, with p < 0.001. The BHQ score, which reflects health-related quality of life, was also significantly lower in the Pseudomonas group (10.5 ± 3.4 vs. 6.6 ± 3.6, p = 0.018) (Table 3).

3.3. Clinical Outcomes Based on Pseudomonas Colonization

Over a 1-year follow-up period, the Pseudomonas group showed a higher risk of hospitalization owing to bronchiectasis (adjusted odds ratio [aOR] 2.19 (95% confidence interval [CI] 1.08–4.42)) and a greater need for antibiotic treatment (aOR 3.04 (95% CI 1.17–7.91)). Additionally, the Pseudomonas group had a lower BHQ score (60.5 ± 11.7 vs. 67.7 ± 11.2, p < 0.001), indicating poorer quality of life (Table 4).

4. Discussion

In this multicenter cohort study of 936 patients, 89 patients with Pseudomonas colonization exhibited distinctive clinical characteristics and outcomes compared with those of the control group. The presence of Pseudomonas colonization significantly correlated with poorer lung function, higher prevalence of COPD, prolonged bronchiectasis duration, and increased radiological extension, notably affecting the lingula and left lower lobe. Furthermore, patients with Pseudomonas colonization had an elevated risk of hospitalization, increased antibiotic requirements over one year, and a lower BHQ score after one year, indicating a diminished quality of life among patients with bronchiectasis. Importantly, these findings remained robust even after adjusting for demographic factors, highlighting the impact of Pseudomonas colonization on the clinical trajectory of bronchiectasis.
P. aeruginosa is a frequently occurring pathogen in patients with bronchiectasis and has detrimental effects on disease progression [21]. Research has shown that its isolation is associated with worse respiratory symptoms [9], poor quality of life [22], and increased airflow obstruction [23]. Furthermore, colonization by P. aeruginosa has been associated with a rapid decline in lung function [7] and frequent exacerbation of bronchiectasis with cystic fibrosis [24] and non-cystic fibrosis bronchiectasis [10,11,25]. It significantly affects the progression and severity of bronchiectasis, resulting in poor lung function, severe radiological features [3,9,18,26], frequent hospitalizations [2,8], and exacerbations [18]. Our study showed similar results for hospital admission and acute exacerbation; no significant difference was observed in acute exacerbation.
In patients with bronchiectasis, those with P. aeruginosa infection experience a faster annual decline in FEV1 [27], especially older patients and those with chronic infection [7]. Therefore, P. aeruginosa infection is associated with a rapid decline in lung function, leading to poor respiratory health and ultimately contributing to disease progression [28]. Various risk factors have been identified for P. aeruginosa infection in patients with bronchiectasis. These include increased duration of bronchiectasis, use of proton pump inhibitors (PPIs) [29], cystic and extensive bronchiectasis, and severe radiological involvement [29,30]. Similar to the results of a previous study, we found that the FEV1 and FVC were lower in Korean patients with bronchiectasis and Pseudomonas colonization. However, we did not observe any longitudinal changes owing to the short follow-up period. In the EMBARC study, 25.5% of the cohort had COPD and 31% had asthma, whereas in this study, 34.4% and 23% of the patients had COPD and asthma, respectively. This difference in the airway disease proportion may have led to differences in pharmacological therapy, which in turn affects lung function and disease prognosis [31].
The BHQ is a simple tool that can be used to assess the quality of life of patients with bronchiectasis and has been validated in many countries [17,32], including Korea [33]. This questionnaire evaluates fatigue, performance, emotional states, and respiratory symptoms. It has a high predictive value for lung function and the risk of severe exacerbation [33]. To our knowledge, this study is the first to demonstrate a significant association between lower BHQ scores in patients with Pseudomonas infection and their persistence after a follow-up period of 1 year.
Previous studies have reported varying rates of Pseudomonas colonization in patients with non-cystic fibrosis bronchiectasis, ranging from 8% to 33% [12,21,29], with a typical incidence of 25%. However, in our study, we observed a very low prevalence of 9.5%. The frequency of colonization can be affected by various factors such as colonization definition, timing of follow-up, country, and race of the study participants [8,34,35]. In our study, the results were based on two separate specimen identifications taken one year apart. It is important to note that the typical definition of colonization requires two positive cultures that are at least three months apart for over a year. Therefore, the true colonization rate may have been underestimated.
The strength of this study lies in its multicenter prospective cohort design conducted within an Asian population, encompassing a large participant pool. Unlike many studies that involved only a limited number of patients recruited from a single center, our investigation has a broader scope. To the best of our knowledge, this is the first prospective study to demonstrate the frequency of acute exacerbations in an Asian population. This is the first study to prospectively demonstrate the impact of P. aeruginosa colonization on the quality of life of patients with bronchiectasis, as measured using the BHQ score.
This study has several limitations. First, the 1-year follow-up period may have been insufficient for a comprehensive assessment of changes in lung function and the frequency of acute exacerbations. Five years of data were not available because the data processing was not completed. Second, we could not establish causality between the adverse outcomes observed in patients with P. aeruginosa colonization and their poorer baseline characteristics, including compromised lung function and more extensive bronchiectasis, than those in patients without P. aeruginosa colonization. To address this limitation, we used propensity score matching and adjusted for baseline factors. Furthermore, the prospective nature of our study helps to mitigate this limitation. Further prospective studies with long-term follow-ups are required. Finally, because COVID-19 occurred during the follow-up period of this cohort, the decrease in the number of follow-up patients may have been influenced by the reluctance to visit the hospital due to COVID-19 concerns or the inability of patients affected by COVID-19 to attend their appointments. This may have resulted in a loss of data after one year, potentially introducing bias.

5. Conclusions

In our multicenter prospective cohort study, patients with bronchiectasis and P. aeruginosa colonization exhibited worse lung function, prolonged duration of bronchiectasis, and greater radiological extension. They experienced an elevated risk of hospitalization and increased antibiotic use during follow-up, as evidenced by low BHQ scores. Further studies are needed to observe the long-term outcomes in patients with bronchiectasis and P. aeruginosa colonization.

Author Contributions

J.S.—Methodology, Formal analysis, Investigation, Data curation, Writing—original draft; Writing—review and editing; S.S.—Conceptualization, Methodology, Formal analysis, Investigation, Data curation, Writing—original draft; Writing—review and editing; H.-R.K.—Methodology, Software, Formal analysis, Investigation, Data curation; Writing—review and editing, Visualization; I.J.—Conceptualization, Validation; Writing—review and editing, Supervision, Project administration; Y.-M.O.—Validation; Writing—review and editing, and Supervision. All authors have read and agreed to the published version of the manuscript.

Funding

Open access funding was enabled and organized by the National Medical Center.

Institutional Review Board Statement

This study was approved by the Institutional Review Board of the National Medical Center (IRB no. H-1807-092-015, 19 July 2018).

Informed Consent Statement

Informed consent was obtained from all subjects enrolled in the study.

Data Availability Statement

Data supporting the conclusions of this article are available from the corresponding author upon request.

Acknowledgments

The authors thank all members of the Korean Multicentre Bronchiectasis Audit and Research Collaboration (KMBARC) registry: Yeon-Mok Oh, Ina Jeong, Sooim Sin, Hayoung Choi, Yun Su Sim, Woo Jin Kim, Kwang Ha Yoo, SL, TK, Bumhee Yang, IJ, Soo-Jung Um, Deog Kyeom Kim, Ji-Hyun Lee, Byoung Soo Kwon, Young-Jae Cho, Chang-Hoon Lee, Chin Kook Rhee, Sang Haak Lee, Ju-Ok Na, An-Soo Jang, Ji Ye Jung, Ji-Ho Lee, Sang Ha Kim, CK, YK, CL, Hyun Kuk Kim, Hye Yun Park, Jae Seung Lee, Sei Won Lee, Seung Won Ra, Sung-Yoon Kang, Yee Hyung Kim, Yong Bum Park, So-Young Park, Junghyun Kim, Young-Soon Yoon, Yun Jeong Jeong, Jung-Kyu Lee, Ki Uk Kim, Hyun-Kyung Lee, Eun Kyung Kim, Se Hee Lee, Jae Sung Choi, Hyung Koo Kang, Yong-Soo Kwon, Jae Ha Lee, Eun Hye Lee, and Ji Soo Choi. This research was supported by the publication fee support from the Researcher Support Project of the Public Health and Medical Research Institute of the National Medical Center. The authors would like to express their sincere gratitude for the financial support which made this publication possible.

Conflicts of Interest

The authors have no potential conflicts of interest to disclose.

Abbreviations

P. aeruginosaPseudomonas aeruginosa; FACED—F: forced expiratory volume in 1 s [FEV1]; A: age; C: chronic colonization by Pseudomonas aeruginosa; E: radiological extension [number of pulmonary lobes affected]; D: dyspnea; BSI—Bronchiectasis Severity Index; BHQ—Bronchiectasis Health Questionnaire.

References

  1. McShane, P.J.; Naureckas, E.T.; Tino, G.; Strek, M.E. Non-cystic fibrosis bronchiectasis. Am. J. Respir. Crit. Care Med. 2013, 188, 647–656. [Google Scholar] [CrossRef]
  2. Kelly, M.G.; Murphy, S.; Elborn, J.S. Bronchiectasis in secondary care: A comprehensive profile of a neglected disease. Eur. J. Intern. Med. 2003, 14, 488–492. [Google Scholar] [CrossRef] [PubMed]
  3. Miszkiel, K.A.; Wells, A.U.; Rubens, M.B.; Cole, P.J.; Hansell, D.M. Effects of airway infection by Pseudomonas aeruginosa: A computed tomographic study. Thorax 1997, 52, 260–264. [Google Scholar] [CrossRef] [PubMed]
  4. Ho, P.L.; Chan, K.N.; Ip, M.S.; Lam, W.K.; Ho, C.S.; Yuen, K.Y.; Tsang, K.W. The effect of Pseudomonas aeruginosa infection on clinical parameters in steady-state bronchiectasis. Chest 1998, 114, 1594–1598. [Google Scholar] [CrossRef] [PubMed]
  5. Vidaillac, C.; Chotirmall, S.H. Pseudomonas aeruginosa in bronchiectasis: Infection, inflammation, and therapies. Expert Rev. Respir. Med. 2021, 15, 649–662. [Google Scholar] [CrossRef] [PubMed]
  6. Chai, Y.H.; Xu, J.F. How does Pseudomonas aeruginosa affect the progression of bronchiectasis? Clin. Microbiol. Infect. 2020, 26, 313–318. [Google Scholar] [CrossRef]
  7. Martinez-García, M.A.; Oscullo, G.; Posadas, T.; Zaldivar, E.; Villa, C.; Dobarganes, Y.; Girón, R.; Olveira, C.; Maíz, L.; García-Clemente, M.; et al. Pseudomonas aeruginosa and lung function decline in patients with bronchiectasis. Clin. Microbiol. Infect. 2021, 27, 428–434. [Google Scholar] [CrossRef]
  8. McDonnell, M.J.; Jary, H.R.; Perry, A.; MacFarlane, J.G.; Hester, K.L.M.; Small, T.; Molyneux, C.; Perry, J.D.; Walton, K.E.; De Soyza, A. Non cystic fibrosis bronchiectasis: A longitudinal retrospective observational cohort study of Pseudomonas persistence and resistance. Respir. Med. 2015, 109, 716–726. [Google Scholar] [CrossRef]
  9. King, P.T.; Holdsworth, S.R.; Freezer, N.J.; Villanueva, E.; Holmes, P.W. Microbiologic follow-up study in adult bronchiectasis. Respir. Med. 2007, 101, 1633–1638. [Google Scholar] [CrossRef]
  10. Chawla, K.; Vishwanath, S.; Manu, M.K.; Lazer, B. Influence of Pseudomonas aeruginosa on exacerbation in patients with bronchiectasis. J. Glob. Infect. Dis. 2015, 7, 18–22. [Google Scholar] [CrossRef]
  11. Rogers, G.B.; Zain, N.M.M.; Bruce, K.D.; Burr, L.D.; Chen, A.C.; Rivett, D.W.; McGuckin, M.A.; Serisier, D.J. A novel microbiota stratification system predicts future exacerbations in bronchiectasis. Ann. Am. Thorac. Soc. 2014, 11, 496–503. [Google Scholar] [CrossRef]
  12. Pieters, A.; Bakker, M.; Hoek, R.A.S.; Altenburg, J.; van Westreenen, M.; Aerts, J.G.J.V.; van der Eerden, M.M. Predicting factors for chronic colonization of Pseudomonas aeruginosa in bronchiectasis. Eur. J. Clin. Microbiol. Infect. Dis. 2019, 38, 2299–2304. [Google Scholar] [CrossRef] [PubMed]
  13. Pasteur, M.C.; Helliwell, S.M.; Houghton, S.J.; Webb, S.C.; Foweraker, J.E.; Coulden, R.A.; Flower, C.D.; Bilton, D.; Keogan, M.T. An investigation into causative factors in patients with bronchiectasis. Am. J. Respir. Crit. Care Med. 2000, 162, 1277–1284. [Google Scholar] [CrossRef] [PubMed]
  14. Lee, H.; Choi, H.; Sim, Y.S.; Park, S.; Kim, W.J.; Yoo, K.H.; Lee, S.J.; Kim, T.H.; Yang, B.; Jeong, I.; et al. KMBARC registry: Protocol for a multicentre observational cohort study on non-cystic fibrosis bronchiectasis in Korea. BMJ Open 2020, 10, e034090. [Google Scholar] [CrossRef]
  15. Lee, H.; Choi, H.; Chalmers, J.D.; Dhar, R.; Nguyen, T.Q.; Visser, S.K.; Morgan, L.C.; Oh, Y.M. Characteristics of bronchiectasis in Korea: First data from the Korean Multicentre Bronchiectasis Audit and Research Collaboration registry and comparison with other international registries. Respirology 2021, 26, 619–621. [Google Scholar] [CrossRef] [PubMed]
  16. Chalmers, J.D.; Aliberti, S.; Polverino, E.; Vendrell, M.; Crichton, M.; Loebinger, M.; Dimakou, K.; Clifton, I.; van der Eerden, M.; Rohde, G.; et al. The EMBARC European Bronchiectasis Registry: Protocol for an international observational study. ERJ Open Res. 2016, 2, 00081–02015. [Google Scholar] [CrossRef]
  17. Spinou, A.; Siegert, R.J.; Guan, W.J.; Patel, A.S.; Gosker, H.R.; Lee, K.K.; Elston, C.; Loebinger, M.R.; Wilson, R.; Garrod, R.; et al. The development and validation of the Bronchiectasis Health Questionnaire. Eur. Respir. J. 2017, 49, 1601532. [Google Scholar] [CrossRef]
  18. Chalmers, J.D.; Goeminne, P.; Aliberti, S.; McDonnell, M.J.; Lonni, S.; Davidson, J.; Poppelwell, L.; Salih, W.; Pesci, A.; Dupont, L.J.; et al. The bronchiectasis severity index. An international derivation and validation study. Am. J. Respir. Crit. Care Med. 2014, 189, 576–585. [Google Scholar] [CrossRef] [PubMed]
  19. Martínez-García, M.Á.; de Gracia, J.; Vendrell Relat, M.; Girón, R.M.; Máiz Carro, L.; de la Rosa Carrillo, D.; Olveira, C. Multidimensional approach to non-cystic fibrosis bronchiectasis: The FACED score. Eur. Respir. J. 2014, 43, 1357–1367. [Google Scholar] [CrossRef]
  20. Hill, A.T.; Haworth, C.S.; Aliberti, S.; Barker, A.; Blasi, F.; Boersma, W.; Chalmers, J.D.; De Soyza, A.; Dimakou, K.; Elborn, J.S.; et al. Pulmonary exacerbation in adults with bronchiectasis: A consensus definition for clinical research. Eur. Respir. J. 2017, 49, 1700051. [Google Scholar] [CrossRef]
  21. Finch, S.; McDonnell, M.J.; Abo-Leyah, H.; Aliberti, S.; Chalmers, J.D. A comprehensive analysis of the impact of Pseudomonas aeruginosa colonization on prognosis in adult bronchiectasis. Ann. Am. Thorac. Soc. 2015, 12, 1602–1611. [Google Scholar] [CrossRef] [PubMed]
  22. Wilson, C.B.; Jones, P.W.; O’Leary, C.J.; Hansell, D.M.; Cole, P.J.; Wilson, R. Effect of sputum bacteriology on the quality of life of patients with bronchiectasis. Eur. Respir. J. 1997, 10, 1754–1760. [Google Scholar] [CrossRef] [PubMed]
  23. Davies, G.; Wells, A.U.; Doffman, S.; Watanabe, S.; Wilson, R. The effect of Pseudomonas aeruginosa on pulmonary function in patients with bronchiectasis. Eur. Respir. J. 2006, 28, 974–979. [Google Scholar] [CrossRef]
  24. Emerson, J.; Rosenfeld, M.; McNamara, S.; Ramsey, B.; Gibson, R.L. Pseudomonas aeruginosa and other predictors of mortality and morbidity in young children with cystic fibrosis. Pediatr. Pulmonol. 2002, 34, 91–100. [Google Scholar] [CrossRef]
  25. Guan, W.-J.; Gao, Y.-H.; Xu, G.; Lin, Z.-Y.; Tang, Y.; Li, H.-M.; Li, Z.-M.; Zheng, J.-P.; Chen, R.-C.; Zhong, N.-S. Effect of airway Pseudomonas aeruginosa isolation and infection on steady-state bronchiectasis in Guangzhou, China. J. Thorac. Dis. 2015, 7, 625–636. [Google Scholar] [CrossRef]
  26. Tsang, K.W.; Chan, K.; Ho, P.; Zheng, L.; Ooi, G.C.; Ho, J.C.; Lam, W. Sputum elastase in steady-state bronchiectasis. Chest 2000, 117, 420–426. [Google Scholar] [CrossRef]
  27. Martínez-García, M.A.; Soler-Cataluña, J.J.; Perpiñá-Tordera, M.; Román-Sánchez, P.; Soriano, J. Factors associated with lung function decline in adult patients with stable non-cystic fibrosis bronchiectasis. Chest 2007, 132, 1565–1572. [Google Scholar] [CrossRef] [PubMed]
  28. Guan, W.J.; Gao, Y.H.; Xu, G.; Lin, Z.Y.; Tang, Y.; Li, H.M.; Lin, Z.M.; Zheng, J.P.; Chen, R.C.; Zhong, N.S. Characterization of lung function impairment in adults with bronchiectasis. PLoS ONE 2014, 9, e113373. [Google Scholar] [CrossRef]
  29. Kwok, W.C.; Ho, J.C.M.; Tam, T.C.C.; Ip, M.S.M.; Lam, D.C.L. Risk factors for Pseudomonas aeruginosa colonization in non-cystic fibrosis bronchiectasis and clinical implications. Respir. Res. 2021, 22, 132. [Google Scholar] [CrossRef]
  30. Gao, Y.H.; Guan, W.J.; Zhu, Y.N.; Chen, R.C.; Zhang, G.J. Antibiotic-resistant Pseudomonas aeruginosa infection in patients with bronchiectasis: Prevalence, risk factors and prognostic implications. Int. J. Chronic Obstr. Pulm. Dis. 2018, 13, 237–246. [Google Scholar] [CrossRef]
  31. Chalmers, J.D.; Polverino, E.; Crichton, M.L.; Ringshausen, F.C.; De Soyza, A.; Vendrell, M.; Burgel, P.R.; Haworth, C.S.; Loebinger, M.R.; Dimakou, K.; et al. Bronchiectasis in Europe: Data on disease characteristics from the European Bronchiectasis registry (EMBARC). Lancet Respir. Med. 2023, 11, 637–649. [Google Scholar] [CrossRef] [PubMed]
  32. Luppo, A.; Rached, S.Z.; Athanazio, R.A.; Stelmach, R.; Corso, S.D. In-person and online application of the Bronchiectasis Health Questionnaire: Are they interchangeable? J. Bras. Pneumol. 2022, 48, e20220075. [Google Scholar] [CrossRef] [PubMed]
  33. Kim, H.K.; Lee, H.; Kim, S.H.; Choi, H.; Lee, J.H.; Lee, J.S.; Lee, S.W.; Oh, Y.M. Validation of the Korean version of the bronchiectasis health questionnaire. Tuberc. Respir. Dis. 2020, 83, 228–233. [Google Scholar] [CrossRef] [PubMed]
  34. Goeminne, P.C.; Nawrot, T.S.; Ruttens, D.; Seys, S.; Dupont, L.J. Mortality in non-cystic fibrosis bronchiectasis: A prospective cohort analysis. Respir. Med. 2014, 108, 287–296. [Google Scholar] [CrossRef]
  35. Hester, K.L.; Macfarlane, J.G.; Tedd, H.; Jary, H.; McAlinden, P.; Rostron, L.; Small, T.; Newton, J.L.; De Soyza, A. Fatigue in bronchiectasis. QJM 2012, 105, 235–240. [Google Scholar] [CrossRef]
Figure 1. Venn diagram representing the isolation of Pseudomonas aeruginosa from the KMBARC registry. Abbreviations: History, History of Pseudomonas aeruginosa isolation from respiratory secretion; First visit, Pseudomonas aeruginosa isolation from respiratory secretion at first visit; 1-year FU, Pseudomonas aeruginosa isolation from respiratory secretion at the 1-year follow-up.
Figure 1. Venn diagram representing the isolation of Pseudomonas aeruginosa from the KMBARC registry. Abbreviations: History, History of Pseudomonas aeruginosa isolation from respiratory secretion; First visit, Pseudomonas aeruginosa isolation from respiratory secretion at first visit; 1-year FU, Pseudomonas aeruginosa isolation from respiratory secretion at the 1-year follow-up.
Jcm 13 05011 g001
Table 1. Baseline Characteristics of matched patients.
Table 1. Baseline Characteristics of matched patients.
VariablesTotal
n = 445
Pseudomonas Group
n = 89
Non-Pseudomonas Group
n = 356
p-Value
Age64.4 ± 9.463.5 ± 9.864.6 ± 9.30.358
Sex, Female, n (%)289 (64.9)56 (62.9)233 (65.5)0.655
BMI22.9 ± 3.523.0 ± 3.523.0 ± 3.50.120
Median duration between BE diagnosed to enrollment, (IQR)3 (1–6)3 (1–6)3 (1–6)0.011
Smoking history, n (%) 0.469
        Current smoker 14 (3.2)1 (1.1)13 (3.7)
        Former smoker111 (25.1)23 (25.8)88 (24.9)
        Never smoker318 (71.8)65 (73.0)253 (71.5)
        Pack-years 3.2 (1.3)2.9 (1.2)3.3 (1.3)0.233
Past medical history, n (%)
        COPD152 (34.4)39 (43.8)113 (32.0)0.036
        Asthma102 (23.0)14 (15.7)88 (24.9)0.069
        History of TB 148 (36.1)35 (39.3)123 (35.2)0.474
        Rhinosinusitis28 (6.3)9 (10.1)19 (5.4)0.100
        Cardiovascular disease131 (29.4)24 (27.0)107 (30.1)0.567
        Pulmonary hypertension15 (3.5)1 (1.2)14 (4.1)0.323
        Stroke11 (2.6)1 (1.2)10 (2.9)0.700
        Diabetes mellitus58 (13.2)5 (6.8)52 (14.7)0.049
        Osteoporosis48 (10.8)66 (6.7)42 (11.8)0.167
        Chronic renal failure9 (2.1)0 (0.0)9 (2.6)0.131
        Cancer, total40 (9.0)4 (4.5)36 (10.2)0.095
        Depression19 (4.3)2 (2.3)17 (4.8)0.390
        Anxiety13 (2.9)2 (2.3)11 (3.1)0.999
Radiologic severity of the bronchiectasis
  Total number of involved lobes, mean (SD)2.4 (1.6)2.7 (1.5)2.3 (1.6)0.021
  Patients with relevant lobe involvement, n (%)
    RUL175 (39.3)43 (48.3)132 (37.1)0.052
    RML257 (57.8)53 (59.6)204 (57.3)0.701
    RLL248 (55.7)57 (64.0)191 (53.7)0.077
    LUL159 (35.7)33 (37.1)126 (35.4)0.767
    Lingula224 (50.3)57 (64.0)167 (46.9)0.004
    LLL319 (71.7)74 (83.2)245 (68.8)0.007
  Cystic bronchiectasis, n (%)200 (44.9)53 (59.6)147 (41.3)0.002
Laboratory findings
   WBC (103/uL)9.6 (3.9) (n = 65)10.3 (3.2) (n = 14)9.4 (4.0) (n = 51)0.437
   Neutrophil (%)70.5 (10.8) (n = 68)73.3 (7.2) (n = 16)69.7 (11.6) (n = 52)0.146
   Lymphocyte (%)20.8 (9.4) (n = 68)18.4 (6.4) (n = 16)21.6 (10.1) (n = 52)0.141
   Monocyte (%)6.3 (2.1) (n = 68)6.6 (1.3) (n = 16)6.2 (2.3) (n = 52)0.454
   Eosinophil (%)1.5 (1.2) (n = 68)1.0 (1.1) (n = 16)1.6(1.3) (n = 52)0.117
   Hemoglobin (g/dL)12.6 (1.5) (n = 65)12.9 (2.0) (n = 14)12.5(1.4) (n = 51)0.456
   Platelet (103/uL)283.1(83.0) (n = 65)303.1(106.3) (n = 14)277.6(75.8) (n = 51)0.314
   Total bilirubin (mg/dL)0.50 (0.03) (n = 70)0.50 (0.05) (n = 16)0.5 (0.04) (n = 54)0.946
   Serum albumin (g/dL)4.0(0.5) (n = 46)4.1 (0.5) (n = 10)4.0 (0.5) (n = 36)0.665
   BUN (mg/dL)15.2 (5.8) (n = 70)14.4 (3.8) (n = 16)15.4 (6.3) (n = 54)0.532
   Creatinine (mt/dL)0.75 (0.24) (n = 70)0.80 (0.19) (n = 16)0.73(0.25) (n = 54)0.318
Past medication history
  Long term macrolide use (≥1 month)20 (6.7)8 (11.3)12 (5.3)0.081
  Inhaled corticosteroid use *78 (17.5)11 (12.4)67 (18.8)0.152
Long term use of bronchodilators †218 (66.1)51 (71.8)167 (64.5)0.246
BE, Bronchiectasis; BMI, Body Mass Index; BUN, Blood Urea Nitrogen; COPD, Chronic Obstructive Pulmonary Disease; IQR, Interquartile Range; LLL, Left Lower Lobe; LUL, Left Upper Lobe; RLL—Right Lower Lobe; RML—Right Middle Lobe; RUL, Right Upper Lobe; SD, Standard Deviation; TB, Tuberculosis * including inhaled corticosteroid (ICS) and ICS/long-acting beta-agonist (LABA) † including ICS/LABA, LABA, and LABA/long-acting muscarinic antagonist. Feature of microbiologic isolations.
Table 2. Isolated microbiology of the study population.
Table 2. Isolated microbiology of the study population.
VariablesPatients Obtained Microbiologic Samples from the Airway in Medically Stable Status
n = 341
Patients from whose respiratory secretion isolated microorganism, n (%) *159 (46.6)
Microorganism, n (%) #
      Pseudomonas aeruginosa92/159 (57.9)
      Streptococcus viridans23/159 (14.5)
      Klebsiella pneumonia10/159 (6.3)
      Staphylococcus aureus10/159 (6.3)
      Hemophilus influenzae7/159 (4.4)
      Escherichia coli7/159 (4.4)
      Enterobacter cloacae4/159 (2.5)
      Streptococcus pneumonia3/159 (1.9)
      Moraxella catarrhalis2/159 (1.2)
      Acinetobacter baumannii1/159 (0.6)
Others §2/159 (1.2)
Source of microbiology. n (%)
        Sputum269 (95.7%)
        Induced sputum10 (2.6%)
BAL, bronchoalveolar lavage * In the non-pseudomonas group, 104 did not perform a sputum test. Among them, 12 patients refused to be tested, 6 were unable to expectorate sputum due to lack of sputum, and 86 had no reason listed. # The denominators were patients with positive sputum culture results. § Others include S. maltophilia, pasteurella multocida The denominators were number of microbiology-detected specimen.
Table 3. Characteristics related to bronchiectasis severity according to Pseudomonas groups.
Table 3. Characteristics related to bronchiectasis severity according to Pseudomonas groups.
Total
n = 445
Pseudomonas Group
n = 89
Non-Pseudomonas Group
n = 356
p-Value
Lung function, mean (SD)
    Pre BD FEV1, absolute [L]1.59 (0.58)1.35 (0.49)1.66 (0.59)<0.001
    Pre BD FEV1, % predicted 64.2 (19.0)56.5 (18.1)66.0 (18.8)<0.001
    Pre BD FVC, absolute [L]2.51 (0.76)2.24 (0.72)2.57 (0.75)<0.001
    Pre BD FVC, % predicted 73.2 (15.7)65.7 (15.5)74.8 (15.3)<0.001
    Post BD FEV1, absolute [L]1.71 (0.58)1.50 (0.57)1.76 (0.58)0.001
    Post BD FEV1, % predicted 66.6 (18.8)58.5 (17.6)68.5 (18.6)<0.001
    Post BD FVC, absolute [L]2.55 (0.75)2.26 (0.72)2.61 (0.75)<0.001
    Post BD FVC, % predicted 73.9 (15.4)66.3 (15.0)75.6 (15.0)<0.001
Respiratory symptom
    mMRC, mean (SD)1.00 (0.84)1.12 (0.99)0.07 (0.80)0.165
    Patient with each mMRC, n (%) 0.175
      mMRC grade ≥ 284 (19.0)22 (24.7)62 (17.5)0.121
      mMRC grade ≥ 328 (6.3)9 (10.1)19 (5.4)0.100
      mMRC grade 45 (1.1)3 (3.4)2 (0.56)0.058
    Sputum color 0.242
        Mucus283 (65.2)59 (66.3)224 (64.9)
        Mucopurulent112 (25.8)18 (20.2)94 (27.3)
        Purulent34 (7.8)10 (11.2)24 (7.0)
        Very Purulent 5 (1.2)2 (2.3)3 (0.9)
      Sputum volume, cc/day mean (SD)26.2 (25.0)21.0 (22.3)29.2 (26.1)0.145
    h/o major hemoptysis, n (%)29 (10.3)9 (14.1)20 (9.1)0.253
Acute exacerbation history
    Presence of AE, n (%)209 (54.3)46 (54.8)163 (54.2)0.921
    Number of AE, mean (SD)1.5 (2.3)1.6 (2.2)1.5 (2.4)0.794
    More than 2 annual exacerbations, n (%) 129 (33.5)30 (35.7)99 (32.9)0.628
    Requiring antibiotics, mean (SD)1.7 (2.1)2.3 (2.5)1.5 (2.0)0.096
    Requiring ER visit, n (%)31 (7.0)9 (10.1)22 (6.2)0.198
    Requiring hospital admission, n (%) 81 (18.3)18 (20.2)63 (17.8)0.596
Hospital admission due to bronchiectasis, n (%) 118 (26.6)30 (33.7)88 (24.9)0.091
BHQ score, mean (SD)63.7 (10.7)61.3 (11.0)64.3 (10.6)0.018
FACED score, mean (SD)2.1 (1.7)3.1 (1.6)1.9 (1.6)<0.001
BSI score, mean (SD)7.4 (3.9)10.5 (3.4)6.6 (3.6)<0.001
AE, Acute exacerbation; BD, Bronchodilator; BHQ, Bronchiectasis Health Questionnaire; BSI, Bronchiectasis Severity Index, ER, Emergency room; FACED, a scoring system for assessing the severity of bronchiectasis including the components FEV1, age, chronic colonization, extension, and dyspnea; FEV1, Forced Expiratory Volume in one second; FVC, Forced Vital Capacity; mMRC, Modified Medical Research Council Dyspnea Scale; SD, Standard Deviation.
Table 4. Clinical outcomes of the study population after 1 year.
Table 4. Clinical outcomes of the study population after 1 year.
Total
n = 445
Pseudomonas Group
n = 89
Non-Pseudomonas Group
n = 356
p-Value
Risk of exacerbation, crude odds ratio (CI) 1.78 (1.07–2.97)Ref0.027
Risk of exacerbation, adjusted odds ratio (CI) * 1.66 (0.98–2.82)Ref0.058
Risk of exacerbation of ED visit, crude odds ratio (CI) 1.95 (0.58–6.57)Ref0.283
Risk of exacerbation of ED visit, adjusted odds ratio (CI) * 1.64 (0.46–5.83)Ref0.441
Risk of admission due to bronchiectasis, crude odds ratio (CI) 2.29 (1.18–4.43)Ref0.014
Risk of admission due to bronchiectasis, adjusted adds ratio (CI) * 2.19 (1.08–4.42)Ref0.028
Risk of hemoptysis, crude odds ratio (CI) 1.48 (0.82–2.64)Ref0.191
Risk of hemoptysis, adjusted adds ratio (CI) * 1.54 (0.85–2.81)Ref0.153
Risk of antibiotics treatment, crude odds ratio (CI) 3.08 (1.22–7.80)Ref0.018
Risk of antibiotics treatment, adjusted adds ratio (CI) * 3.04 (1.17–7.91)Ref0.022
BHQ score *66.0 (11.7) (n = 236)60.5 (11.7) (n = 54)67.7 (11.2) (n = 182)<0.001
FACED score * 2.1 (1.6) (n = 37)3.0 (2.2) (n = 8)1.9 (1.4) (n = 29)0.080
BSI score *7.6 (4.3) (n = 37)8.8 (4.9) (n = 8)7.2 (4.1) (n = 29)0.345
BHQ, Bronchiectasis Health Questionnaire; BSI, Bronchiectasis Severity Index; ED, emergency department, FACED, a scoring system for assessing the severity of bronchiectasis, including FEV1, age, chronic colonization, extension, and dyspnea; CI, confidence interval. * Adjusted for age, sex, and BMI.
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MDPI and ACS Style

Song, J.; Sin, S.; Kang, H.-R.; Oh, Y.-M.; Jeong, I., on behalf of the KMBARC. Clinical Impacts of Pseudomonas aeruginosa Isolation in Patients with Bronchiectasis: Findings from KMBARC Registry. J. Clin. Med. 2024, 13, 5011. https://doi.org/10.3390/jcm13175011

AMA Style

Song J, Sin S, Kang H-R, Oh Y-M, Jeong I on behalf of the KMBARC. Clinical Impacts of Pseudomonas aeruginosa Isolation in Patients with Bronchiectasis: Findings from KMBARC Registry. Journal of Clinical Medicine. 2024; 13(17):5011. https://doi.org/10.3390/jcm13175011

Chicago/Turabian Style

Song, Jinhwa, Sooim Sin, Hye-Rin Kang, Yeon-Mok Oh, and Ina Jeong on behalf of the KMBARC. 2024. "Clinical Impacts of Pseudomonas aeruginosa Isolation in Patients with Bronchiectasis: Findings from KMBARC Registry" Journal of Clinical Medicine 13, no. 17: 5011. https://doi.org/10.3390/jcm13175011

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