Bronchiectasis and increased mortality in patients with corticosteroid-dependent severe asthma: a nationwide population study

The Impact of Bronchiectasis on the Clinical Characteristics of Non-Severe Asthma

Current literature primarily delves into the relationship between bronchiectasis and severe asthma, and only a few studies have evaluated the impact of bronchiectasis in patients with non-severe asthma. Therefore, this study investigated the clinical impact of bronchiectasis in patients with non-severe asthma. A prospective observational study of 140 non-severe asthmatic patients with (bronchiectasis group) and without bronchiectasis (control group) was conducted between September 2012 and February 2022. The bronchiectasis and control groups were compared in terms of demographics, lung function, asthma control test (ACT) results, exacerbation history, and respiratory medications. Among 140 non-severe asthmatic subjects, approximately 15.7% (n = 22) had bronchiectasis. The most common type of bronchiectasis was cylindrical type (90.7%). The left lingular division was the most frequently involved lung lobe (20.4%). There were no significant differences in the demographics (age, sex, body mass index, smoking history, and comorbidities) or ACT results between the 2 groups. The bronchiectasis group used inhaled corticosteroids/long-acting β2-agonists (P = 0.074) and mucolytics (P < 0.001) more frequently than the control group. Compared to the control group, the bronchiectasis group had lower forced expiratory volume in 1 second (FEV1) (L) (1.9 ± 0.7 L vs. 2.3 ± 0.9 L, P = 0.039) and FEV1%predicted (67.2 ± 22.2%predicted vs. 77.1 ± 20.0%predicted, P = 0.038). The rate of hospital admission to a general ward in the preceding year was significantly higher in the bronchiectasis group compared to those of the control group (23.8% vs. 3.5%, P = 0.005) with an adjusted odds ratio of 6.308 (95% confidence interval, 1.401-28.392). Patients with non-severe asthma and bronchiectasis had lower lung function and more frequent exacerbations requiring hospitalization than those without bronchiectasis. More attention is needed for asthmatic patients with bronchiectasis, even if the asthma is not severe.

Bacteria and viruses and clinical outcomes of asthma-bronchiectasis overlap syndrome: A cohort study

BACKGROUND

Despite the high prevalence of co-existing bronchiectasis and asthma (asthma-bronchiectasis overlap syndrome [ABOS]), little is known regarding the dominant pathogens and clinical correlates.

OBJECTIVE

To investigate the bacteria and viruses which differentially dominate in ABOS (including its subtypes) compared with bronchiectasis alone, and determine their relevance with bronchiectasis severity and exacerbations.

METHODS

This was a prospective observational cohort study conducted between March 2017 and August 2023. We included 81 patients with ABOS and 107 patients with bronchiectasis alone. At steady-state baseline, patients underwent comprehensive assessments and sputum collection for bacterial culture and viral detection (quantitative polymerase-chain-reaction). Patients were followed-up to record exacerbation and spirometry.

RESULTS

Patients with ABOS had significantly higher symptom burden and exacerbation frequency than those with bronchiectasis alone. Despite similar pathogen spectrum, the rate of bacteria-virus co-detection increased less substantially at acute exacerbations (AE) onset than at steady-state compared with bronchiectasis alone. Pathogenic bacteria (particularly Pseudomonas aeruginosa) were detected fairly common (exceeding 50%) in ABOS and were associated with greater severity of bronchiectasis when stable and conferred greater exacerbation risks at follow-up. Viral but not bacterial compositions changed substantially at AE onset compared with clinical stability. Higher blood eosinophil count, moderate-to-severe bronchiectasis and non-atopy were associated with higher odds of bacterial, but not viral, detection (all p < 0.05).

CONCLUSION

Detection of bacteria or virus is associated with bronchiectasis severity or clinical outcomes in ABOS. This highlights the importance of integrating sputum microbial assessment for ascertaining the dominant pathophysiology (atopy vs. infection) and longitudinal trajectory prediction in ABOS.

Increased Risk of New-Onset Asthma After COVID-19: A Nationwide Population-Based Cohort Study

BACKGROUND

Previous studies have suggested that respiratory virus infections may be associated with new-onset asthma. However, whether coronavirus disease 2019 (COVID-19) is associated with an increased risk of new-onset asthma remains unclear.

OBJECTIVE

We aimed to evaluate whether recent COVID-19 increases the risk of new-onset asthma and whether COVID-19 vaccination could mitigate this risk.

METHODS

We constructed 3 different study designs using the Korean National Health Insurance claim-based database: study 1: COVID-19-diagnosed subjects (COVID-19 cohort) and their matched controls; study 2: COVID-19-vaccinated subjects (vaccination cohort) and their matched controls; and study 3: vaccination cohort and their matched controls, excluding subjects diagnosed with COVID-19.

RESULTS

In study 1, 1.6% of the COVID-19 cohort and 0.7% of the matched cohort developed new-onset asthma, with incidences of 31.28 and 14.55 per 1,000 person-years, respectively (P < .001). The COVID-19 cohort had a higher risk of new-onset asthma (adjusted hazard ratio [aHR] 2.14; 95% CI 1.88-2.45) than matched controls. In study 2, the vaccination cohort had a lower risk of new-onset asthma than the matched controls (aHR 0.82; 95% CI 0.76-0.89). However, among subjects without a COVID-19 diagnosis, COVID-19 vaccination was not associated with a reduced risk of new-onset asthma in study 3 (aHR 0.95; 95% CI 0.87-1.04). In subgroup analysis, the risk of new-onset asthma was significantly lower in fully vaccinated subjects and higher in older subjects and in those with diabetes mellitus than in their counterparts.

CONCLUSIONS

The COVID-19 was associated with a higher incidence of new-onset asthma, which might be preventable by COVID-19 vaccination.

Does asthma-bronchiectasis overlap syndrome (ABOS) really exist?

OBJECTIVE

To analyze the relationship between asthma and bronchiectasis, as well as the necessary conditions that this connection must meet for this group of patients to be considered a special phenotype.

DATA SOURCES

We performed a PubMed search using the MeSH terms "asthma" and "bronchiectasis." The literature research was limited to clinical trials, meta-analyses, randomized controlled trials, cohort studies, and systematic reviews, involving adult patients, published until November 30th, 2022.

STUDY SELECTIONS

Selected papers were initially evaluated by the Authors, to assess their eligibility in contributing to the statements.

RESULTS

The prevalence of bronchiectasis is higher than expected in patients with asthma, particularly in those with more severe disease, and in some patients, between 1.4% and 7% of them, asthma alone could be the cause of bronchiectasis. Both diseases share etiopathogenic mechanisms, such as neutrophilic and eosinophilic inflammation, altered airway microbiota, mucus hypersecretion, allergen sensitization, immune dysfunction, altered microRNA, dysfunctional neutrophilic activity, and variants of the HLA system. Besides that, they also share comorbidities, such as gastroesophageal reflux disease and psychiatric illnesses. The clinical presentation of asthma is very similar to patients with bronchiectasis, which could cause mistakes with diagnoses and delays in being prescribed the correct treatment. The coexistence of asthma and bronchiectasis also poses difficulties for the therapeutic focus.

CONCLUSIONS

The evidence available seems to support that the asthma-bronchiectasis phenotype really exists although longitudinal studies which consistently demonstrate that asthma is the cause of bronchiectasis are still lacking.

Impact of air pollution on healthcare utilization in patients with bronchiectasis

Introduction

Air pollutants are increasingly recognized to affect long-term outcomes in patients with bronchiectasis. We aimed to figure out the association between air pollutants and the risk of healthcare utilization in patients with bronchiectasis.

Methods

Data for 1,029 subjects with bronchiectasis in Seoul were extracted. The air pollutants included particulate matter of 10 μm or less in diameter (PM10), particulate matter of 2.5 μm or less in diameter (PM2.5), sulfur dioxide (SO2), carbon monoxide (CO), ozone (O3), and nitrogen dioxide (NO2). The outcome was all-cause healthcare uses, defined as outpatient visit, emergency department visit, or hospitalization. The concentration-response curves between each air pollutant and relative risks for healthcare utilization were obtained.

Results

There were significant correlations between air pollutant concentrations and the risk of healthcare utilization, particularly for PM10, NO2, SO2, and CO. This risk was observed even at concentrations below the recommended safe thresholds for the general population. The slopes for the association between PM10 and NO2 and the risk of healthcare use showed a logarithmic growth pattern, with the steepest increase up to 30 μg/m3 and 0.030 parts per million (ppm), respectively. The curves for SO2 and CO showed an inverted U-shaped pattern, with a peak at 0.0045 ppm and a slow upward curve, respectively. No specific trends were observed for PM2.5 and O3 and the risk of healthcare use.

Discussion

Increased concentrations of PM10, NO2, SO2, and CO were associated with increased healthcare utilization in patients with bronchiectasis. For patients with bronchiectasis, there were no safety thresholds for those air pollutants, and even low levels of air pollutant exposure can negatively impact bronchiectasis outcomes.

Management of comorbidities in difficult and severe asthma

Difficult-to-treat and severe asthma are challenging clinical entities. In the face of suboptimal asthma control, the temptation for clinicians is to reflexively escalate asthma-directed therapy, including increasing exposure to corticosteroids and commencement of costly but potent biologic therapies. However, asthma control is objectively and subjectively assessed based on measurable parameters (such as exacerbations or variability in pulmonary physiology), symptoms and patient histories. Crucially, these features can be confounded by common untreated comorbidities, affecting clinicians' assessment of asthma treatment efficacy.

Real-World Effectiveness of IL-5/5Ra Targeted Biologics in Severe Eosinophilic Asthma With Comorbid Bronchiectasis

BACKGROUND

Bronchiectasis is a common comorbidity in patients with asthma and is associated with increased disease severity. In patients with severe eosinophilic asthma, biologics targeting IL-5/5Ra have beneficial effects on oral corticosteroid (OCS) use and exacerbation frequency. However, how coexisting bronchiectasis affects the response to such treatments is unknown.

OBJECTIVE

To evaluate the real-world effectiveness of anti-IL-5/5Ra therapy in patients with severe eosinophilic asthma and comorbid bronchiectasis on exacerbation frequency and daily maintenance and cumulative OCS dose.

METHODS

This real-world study evaluated data from 97 adults with severe eosinophilic asthma and computed tomography-confirmed bronchiectasis from the Dutch Severe Asthma Registry, who initiated anti-IL5/5Ra biologics (mepolizumab, reslizumab, and benralizumab) and had follow-up data for 12 months or greater. The analysis was performed for the total population and subgroups with or without maintenance OCS use.

RESULTS

Anti-IL-5/5Ra therapy significantly reduced exacerbation frequency in patients with maintenance OCS use as well as in those without it. In the year before biologic initiation, 74.5% of all patients had two or more exacerbations, which decreased to 22.1% in the follow-up year (P < .001). The proportion of patients on maintenance OCS decreased from 47% to 30% (P < .001), and in the OCS-dependent patients (n = 45) maintenance OCS dose decreased from median (interquartile range) of 10.0 mg/d (5-15 mg/d) to 2.5 mg/d (0-5 mg/d) after 1 year (P < .001).

CONCLUSIONS

This real-world study shows that anti-IL-5/5Ra therapy reduces exacerbation frequency and daily maintenance as well as the cumulative OCS dose in patients with severe eosinophilic asthma and comorbid bronchiectasis. Although it is an exclusion criterion in phase 3 trials, comorbid bronchiectasis should not preclude anti-IL-5/5Ra therapy in patients with severe eosinophilic asthma.

Additive effects of coexisting respiratory comorbidities on overall or respiratory mortality in patients with asthma: a national cohort study

Asthmatic patients are generally considered to have an increased risk of mortality compared with subjects without asthma. However, this issue has been less evaluated using nationally representative data. Moreover, it is unclear whether respiratory comorbidities other than chronic obstructive pulmonary disease (COPD) are associated with increased mortality in asthmatic patients compared with subjects without. Using a nationally representative sample database, we performed a retrospective cohort study of patients with asthma and age-sex-matched control cohort. We estimated the hazard ratio (HR) and stratified the asthma cohort based on respiratory comorbidities. During a median 8.9-year follow-up, the overall mortality rate was higher in the asthma cohort than in the control cohort (p < 0.001). The hazard ratio (HR) for overall mortality in the asthma cohort compared with the control cohort was 1.13. The effects of asthma on overall mortality were more evident in males, patients under medical aid, and subjects with COPD. Respiratory comorbidities were significantly associated with increased risk of overall mortality in asthmatic patients compared with controls (adjusted HRs; 1.48 for COPD, 1.40 for bronchiectasis, 4.08 for lung cancer, and 1.59 for pneumonia). While asthma and lung cancer showed an additive effect only on overall mortality, asthma and other respiratory comorbidities (COPD, pneumonia, and bronchiectasis) had additive effects only on respiratory mortality. Patients with asthma had a higher overall mortality rate compared with subjects without asthma. Respiratory comorbidities showed an additive effect on overall or respiratory mortality in patients with asthma.

Association between Smoking Status and Incident Non-Cystic Fibrosis Bronchiectasis in Young Adults: A Nationwide Population-Based Study

Smoking traditionally has not been considered as a cause of bronchiectasis. However, few studies have evaluated the association between smoking and bronchiectasis. This study aimed to investigate the association between smoking status and bronchiectasis development in young adults. This study included 6,861,282 adults aged 20−39 years from the Korean National Health Insurance Service database 2009−2012 who were followed-up until the date of development of bronchiectasis, death, or 31 December 2018. We evaluated the incidence of bronchiectasis according to smoking status. During a mean of 7.4 years of follow-up, 23,609 (0.3%) participants developed bronchiectasis. In multivariable Cox regression analysis, ex-smokers (adjusted hazard ratio (aHR) = 1.07, 95% confidence interval (CI) = 1.03−1.13) and current-smokers (aHR = 1.06, 95% CI = 1.02−1.10) were associated with incident bronchiectasis, with the highest HR in ≥ 10 pack-years current smokers (aHR = 1.12, 95% CI = 1.06−1.16). The association of smoking with bronchiectasis was more profound in females than in males (p for interaction < 0.001), in younger than in older participants (p for interaction = 0.036), and in the overweight and obese than in the normal weight or underweight (p for interaction = 0.023). In conclusion, our study shows that smoking is associated with incident bronchiectasis in young adults. The association of smoking with bronchiectasis development was stronger in females, 20−29 year-olds, and the overweight and obese than in males, 30−40-year-olds, and the normal weight or underweight, respectively.

Influence of Comorbidities and Airway Clearance on Mortality and Outcomes of Patients With Severe Bronchiectasis Exacerbations in Taiwan

Bronchiectasis is characterized by systemic inflammation and multiple comorbidities. This study aimed to investigate the clinical outcomes based on the bronchiectasis etiology comorbidity index (BACI) score in patients hospitalized for severe bronchiectasis exacerbations. We included non-cystic fibrosis patients hospitalized for severe bronchiectasis exacerbations between January 2008 and December 2016 from the Chang Gung Research Database (CGRD) cohort. The main outcome was the 1-year mortality rate after severe exacerbations. We used the Cox regression model to assess the risk factors of 1-year mortality. Of 1,235 patients who were hospitalized for severe bronchiectasis exacerbations, 641 were in the BACI < 6 group and 594 in the BACI ≥ 6 group. The BACI ≥ 6 group had more previous exacerbations and a lower FEV₁. Pseudomonas aeruginosa (19.1%) was the most common bacterium, followed by Klebsiella pneumoniae (7.5%). Overall, 11.8% of patients had respiratory failure and the hospital mortality was 3.0%. After discharge, compared to the BACI < 6 group, the BACI ≥ 6 group had a significantly higher cumulative incidence of respiratory failure and mortality in a 1-year follow-up. The risk factors for 1-year mortality in a multivariate analysis include age [hazard ratio (HR) 4.38, p = 0.01], being male (HR 4.38, p = 0.01), and systemic corticosteroid usage (HR 6.35, p = 0.001), while airway clearance therapy (ACT) (HR 0.50, p = 0.010) was associated with a lower mortality risk. An increased risk of respiratory failure and mortality in a 1-year follow-up after severe exacerbations was observed in bronchiectasis patients with multimorbidities, particularly older age patients, male patients, and patients with a history of systemic corticosteroid use. ACT could effectively improve the risk for 1-year mortality.

Female Reproductive Factors and the Risk of Bronchiectasis: A Nationwide Population-Based Longitudinal Study

Although the oestrogen level is thought to be involved in the occurrence of bronchiectasis, limited data are available on the relationship between female reproductive factors and the risk of bronchiectasis. We performed a population-based retrospective cohort study of 959,523 premenopausal women and 1,362,401 postmenopausal women without a previous history of bronchiectasis who participated in a health screening exam in 2009 in South Korea. In premenopausal women, compared with a later age at menarche (≥16 years), an earlier menarche (<12 years) was associated with a reduced risk of bronchiectasis with an adjusted hazard ratio (aHR) (95% confidence interval (CI)) of 0.74 (0.67–0.81). However, there were no significant associations between other reproductive factors (breastfeeding, parity, or oral contraceptive use) and the risk of bronchiectasis. In postmenopausal women, the risk of bronchiectasis (aHR (95% CI)) was lower in those with an earlier menarche (0.79 (0.72–0.87) for <12 years vs. ≥16 years), a later menopause (0.90 (0.84–0.96) ≥55 years vs. <40 years), and a longer reproductive period (0.90 (0.86–0.94) for ≥40 years vs. <30 years). There was no significant relationship between parity and the risk of bronchiectasis. Although breastfeeding <1 year (aHR (95% CI) = 0.92 (0.87–0.97) for <0.5 years and 0.93 (0.88–0.97) for 0.5–1 years) and oral contraceptive use <1 year (0.97 (0.94–0.99)) reduced the risk of bronchiectasis, hormone replacement therapy ≥5 years increased the risk of bronchiectasis (1.24 (1.18–1.30)). Female reproductive factors are risk factors for developing bronchiectasis, showing a higher risk associated with shorter endogenous oestrogen exposure regardless of the menopausal status.

Bronchiectasis in severe asthma and asthmatic components in bronchiectasis

Asthma and bronchiectasis are different diseases; however, differentiating them can be difficult because they share several symptomatic and physiological similarities. Approximately 20% of patients with bronchiectasis have eosinophilic inflammation, 34% show wheezing, and 7-46% have comorbid asthma, although comorbidity with severe asthma may be limited as shown in 3.3% of cases of bronchiectasis. Meanwhile, 25-68% of patients with severe asthma have comorbid bronchiectasis, and at least two phenotypes are present in the accompanying bronchiectasis: eosinophilic bronchiectasis and chronic infectious bronchiolitis/bronchiectasis. Recent studies show that type-2-targeted biologics are effective for eosinophilic bronchiectasis and theoretically effective for some of the remaining cases when used before oral corticosteroids. Further studies are needed to identify treatment strategies for severe asthma with comorbid bronchiectasis and vice versa.

Long-Term Prognosis of Asthma-Bronchiectasis Overlapped Patients: A Nationwide Population-Based Cohort Study

Purpose

Asthma and bronchiectasis are common chronic respiratory diseases, and their coexistence is frequently observed but not well investigated. Our aim was to study the effect of comorbid bronchiectasis on asthma.

Methods

A propensity score-matched cohort study was conducted using the National Health Insurance Service-Health Screening Cohort database. From 2005 to 2008, 8,034 participants with asthma were weighted based on propensity scores in a 1:3 ratio with 24,099 participants without asthma. From the asthma group, 141 participants with overlapped bronchiectasis were identified, and 7,892 participants had only asthma. Clinical outcomes of acute asthma exacerbation(s) and mortality rates were compared among the study groups.

Results

The prevalence of bronchiectasis (1.7%) was 3 times higher in asthmatics than in the general population of Korea. Patients who had asthma comorbid with bronchiectasis experienced acute exacerbation(s) more frequently than non-comorbid patients (11.3% vs. 5.8%, P = 0.007). Time to the first acute exacerbation was also shorter in the asthmatics with bronchiectasis group (1,970.9 days vs. 2,479.7 days, P = 0.005). Although bronchiectasis was identified as a risk factor for acute exacerbation (adjusted odds ratio, 1.73; 95% confidence interval [CI], 1.05–2.86), there was no significant relationship between bronchiectasis and all-cause or respiratory mortality (adjusted hazard ratio [aHR], 1.17; 95% CI, 0.67–2.04 and aHR, 0.81; 95% CI, 0.11–6.08).

Conclusions

Comorbid bronchiectasis increases asthma-related acute exacerbation, but it does not-raise the risk of all-cause or respiratory mortality. Close monitoring and accurate diagnosis of bronchiectasis are required for patients with frequent exacerbations of asthma.

Respiratory symptoms and health-related quality of life in post-tuberculosis subjects with physician-diagnosed bronchiectasis: a cross-sectional study

Background

Prevalence, respiratory symptoms, and quality of life (QoL) in post-tuberculosis (TB) subjects with bronchiectasis are not well elucidated.

Methods

Subjects who participated in the Korea National Health and Nutritional Examination Survey 2007–2009 were enrolled in this cross-sectional study. We evaluated the prevalence of physician-diagnosed bronchiectasis among post-TB subjects. We compared respiratory symptoms, physical activity limitations, and QoL between post-TB subjects with and without bronchiectasis.

Results

The prevalence of bronchiectasis was 3.3% among 963 post-TB subjects. Post-TB subjects with bronchiectasis showed a higher rate of asthma (29.6% vs. 4.9%, P<0.001) than those without bronchiectasis. Post-TB subjects with bronchiectasis showed more cough (23.9% vs. 6.7%, P=0.033) and physical activity limitations due to respiratory diseases (35.0% vs. 8.9%, P=0.033) than those without bronchiectasis. Furthermore, compared with post-TB subjects without bronchiectasis, those with bronchiectasis had lower QoL measured by the EuroQoL five-dimension (EQ-5D) index (0.84 vs. 0.93, P=0.048). Linear regression analysis found that the EQ-5D index in post-TB subjects with bronchiectasis was significantly lower than in those without bronchiectasis (difference estimate =–0.089, P=0.030), especially in the anxiety/depression component.

Conclusions

Post-TB subjects with bronchiectasis had more cough and physical activity limitations and lower health-related QoL than those without bronchiectasis.

Asthma and Comorbid Conditions-Pulmonary Comorbidity

Pulmonary comorbidities can increase disease severity and health care costs associated with asthma management. Vocal cord dysfunction/inducible laryngeal obstruction is a common comorbidity that results from intermittent laryngeal obstruction. Patients describe distinct episodes of dyspnea that do not respond to bronchodilators. Inspiratory stridor is common. The gold standard diagnostic testing strategy is continuous laryngoscopy performed during exercise or irritant challenges. Dysfunctional breathing (DB) is an overarching term that describes conditions with a chronic change in the pattern of breathing that results in pulmonary and extrapulmonary symptoms. The prevalence of DB in asthma is up to 30%, and breathing retraining can improve symptoms and quality of life in people with DB and asthma. Asthma-chronic obstructive pulmonary disease overlap (ACO) refers to both asthmatics who develop fixed airflow obstruction after a history of exposure to smoke or biomass and patients with chronic obstructive pulmonary disease who have "asthmatic features" such as a large bronchodilator response, elevated levels of serum IgE, or peripheral eosinophil counts ≥300 per μL. Triple inhaler therapy with inhaled corticosteroid/long-acting beta-agonist/long-acting muscarinic should be considered in people with ACO and severe symptoms or frequent exacerbations. The clinical expression of bronchiectasis involves persistent mucus hypersecretion, recurrent exacerbations of infective bronchitis, incompletely reversible airflow obstruction, and lung fibrosis and can occur in up to 30% of adults with longstanding asthma. The treatable traits strategy is a useful model of care to manage the complexity and heterogeneity of asthma with pulmonary comorbidity.