Wang Chun Kwok

As we conclude this enriching Special Issue on “Vaccination for Patients with Respiratory Diseases,” we are reminded of the vital importance of immunization as a cornerstone in protecting some of the most vulnerable populations from severe respiratory infections

Rationale: Chronic obstructive pulmonary disease (COPD) is known to be associated with substantial health‐care utilization and economic costs. Since the COVID‐19 pandemic, the epidemiology of various diseases has undergone significant changes, it is important to evaluate the health‐care impact and economic burden of acute exacerbations of COPD (AECOPD) in the post‐pandemic period, along with factors influencing this burden, to inform effective management strategies and health‐care planning. Objectives: To assess the health‐care and economic burden of severe AECOPD from 2022 to 2024, and to identify factors associated with direct health‐care costs. Methods: A territory‐wide retrospective cohort study was conducted. Adult patients with AECOPD admitted to acute public hospitals in Hong Kong were included. The primary outcomes were the total number of AECOPD admissions and the associated direct health‐care costs. Measurements and Main Results: From 2022 to 2024, a total of 11,465 patients were admitted to acute public hospitals for severe AECOPD, resulting in 25,053 hospitalization episodes and 150,717 bed days. The estimated direct health‐care costs totaled 1.259 billion Hong Kong dollars (HKD). AECOPD admission numbers increased significantly over the 3 years. Patients with eosinophilic and non‐eosinophilic phenotypes had similar annual direct health‐care costs related to severe AECOPD. Patients with co‐existing bronchiectasis had a significantly higher annual number of severe AECOPD episodes and direct health‐care costs from severe AECOPD. Conclusions: Severe AECOPD imposes a substantial burden on the health‐care system. The presence of bronchiectasis and a greater frequency of severe AECOPD episodes were identified as possible factors linked to increased direct health‐care costs.

Background: Type 2 (T2)-low asthma is a heterogeneous endotype associated with neutrophilic or paucigranulocytic airway inflammation, reduced corticosteroid responsiveness, and poorer clinical outcomes. Selected T2-low-associated asthma phenotypes—particularly late-onset disease, obesity-associated asthma, and menopause-associated asthma—are more frequently observed in women, suggesting that sex-specific biological and environmental factors influence disease expression. This review synthesizes the current evidence on the determinants of T2-low asthma in women, with a focus on epidemiology, pathophysiological mechanisms, and therapeutic implications. Methods: PubMed, Embase, and Scopus were searched for English-language articles published up to July 2026. Search terms included keywords related to T2-low asthma, sex differences, reproductive factors, obesity, and smoking. Results: The reported prevalence of T2-low asthma varies from 14% to 50% with neutrophilic asthma accounting for 20% to 30% of patients. In women, estrogen signaling and hormonal variability across the menstrual cycle and menopause may contribute to T helper 17 (Th17)-skewed neutrophilic inflammation, while obesity and smoking may exacerbate disease severity and reduce corticosteroid sensitivity. Management includes weight reduction, smoking cessation, comorbidity optimization, and selected add-on therapies, including macrolides, long-acting muscarinic antagonists (LAMAs), tezepelumab, and novel therapies such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) in obesity-associated asthma. Conclusions: The absence of validated positive biomarkers remains a critical barrier to accurate diagnosis, patient stratification, and targeted therapy development. Important limitations include heterogeneous study populations and predominantly observational data. Improved understanding of sex-specific influences on T2-low asthma may enhance recognition and guide personalized therapeutic strategies, reducing disease burden in this underserved population.

Introduction. While rhinovirus was thought to cause mild infections such as the common cold, severe infections such as community-acquired pneumonia and asthma exacerbations can also occur. Children with chronic medical conditions have been shown to have increased risks of severe infections. Hypothesis/Gap statement. There is a difference in the risks of serious in-hospital outcomes among adults hospitalized for rhinovirus or influenza virus infection. Multiple morbidities in adult patients are associated with severe infections among patients hospitalized for rhinovirus infections. Aim. To compare the risks of serious in-hospital outcomes among adults hospitalized for rhinovirus or influenza virus infection and assess the association between multiple morbidities as represented by Charlson comorbidity index (CCI) in predicting risks of severe infections among patients hospitalized for rhinovirus infections. Methodology. We conducted a territory-wide retrospective study on adults hospitalized for rhinovirus or influenza virus infection between 1 January 2016 and 30 June 2023 in Hong Kong. The in-patient mortality, severe respiratory failure (SRF), secondary bacterial pneumonia and acute kidney injury (AKI) were compared. The association between multi-morbidities as reflected by CCI and severe in-hospital outcomes among adult patients hospitalized for rhinovirus infections was also assessed. Results. A total of 41,206 and 2,222 patients were hospitalized for influenza and rhinovirus infections, respectively. Patients with rhinovirus infection showed a significantly higher risk of SRF, secondary bacterial pneumonia and AKI compared to those with seasonal influenza ( P Conclusion. Adults hospitalized for rhinovirus infection were associated with a significantly increased risk of adverse respiratory and kidney outcomes compared with those with seasonal influenza. More medical comorbidities, as reflected by CCI, were shown to be associated with an increased risk of severe in-hospital outcomes.

Background: Antimicrobial resistance (AMR) is a global threat for people with chronic lung infection; however, international AMR epidemiology in bronchiectasis and cystic fibrosis (CF) is poorly characterised. In this study, we retrospectively analyse international longitudinal AMR epidemiology in bronchiectasis and CF. Methods: Microbiology data were analysed from 110 323 respiratory samples in 19 143 individuals with bronchiectasis or CF across 11 cities, eight countries, three continents between 2011 and 2024. Longitudinal AMR prevalence, multidrug-resistant (MDR) and extensively drug-resistant (XDR) prevalence and multiple antibiotic resistance (MAR) index were analysed by disease and country. Pilot analysis of concurrent/disjoint resistance in antimicrobial pairs and triplets in regional datasets was performed to inform combination or cyclical antimicrobial choice. Findings: Geographic AMR differences were noted across pathogens in bronchiectasis and CF with increased Pseudomonas aeruginosa resistance in central/southern Europe and increased Klebsiella pneumoniae resistance in Hong Kong. MDR burden was high in emergent pathogens Escherichia coli (CF: MDR 32.6%; XDR 12.4%; bronchiectasis: MDR 39.2%; XDR 4.9%) and K. pneumoniae (CF: MDR 22.7%; XDR 15.6%; bronchiectasis: MDR 13.4%; XDR 1.5%). A longitudinal rise in P. aeruginosa AMR was seen in bronchiectasis across four centres for antipseudomonal aminoglycosides (pK. pneumoniae AMR was seen for cephalosporins (p=0.01; OR/year 1.32; 95% CI 1.06 to 1.65) and carbapenems (p=0.04; OR/year 1.64; 95% CI 1.03 to 2.62). A significant increase in AMR, as measured by the MAR index, was observed in individuals with residual culture-positive CF receiving triple cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy (p<0.001). Strong concurrent resistance was noted in bronchiectasis across regions with geographic variation in disjoint antimicrobial pair resistance. Conclusion: We show a significant increasing international AMR burden in bronchiectasis and CF, with geographic variation and persistence post-CFTR modulator therapy.

Introduction: The association between co-morbidities and bronchiectasis have been well recognized, in particular cardiovascular complications. It would be worthwhile to study the impacts of cardiovascular-kidney-metabolic (CKM) syndrome on clinical outcomes in bronchiectasis. Methods: This was a territory-wide retrospective study conducted in Hong Kong between 1993 and 2017. The risks of bacterial pneumonia, viral pneumonia, hospitalized bronchiectasis exacerbation, all-cause mortality, respiratory mortality and CKM-related mortality in patients with different CKM syndrome stages were compared. Results: A total of 8945 subjects were included [6808 (76.1%) with Stage 0 to 1, 1130 (12.6%) with stage 2 to 3, and 1007 (11.3%) with stage 4 CKM syndrome respectively]. Patients with stage 2-3 and 4 CKM syndrome showed increased risks of bacterial pneumonia [adjusted hazard ratio (aHR) 1.45 (95% CI 1.30-1.62, p < 0.001) and 1.74 (95% CI 1.56-1.94, p < 0.001) respectively], all-cause mortality [aHR 1.52 (95% CI 1.37-1.70, p < 0.001) and 1.91 (95% CI 1.72-2.12, p < 0.001) respectively], respiratory-related mortality [aHR 1.45 (95% CI 1.27-1.67, p < 0.001) and 1.82 (95% CI 1.59-2.08, p < 0.001) respectively] and CKM-related mortality [aHR 2.57 (95% CI 1.84-3.57, p < 0.001) and 4.07 (95% CI 3.00-5.52, p < 0.001) respectively] when compared to patients with stage 0-1 CKM syndrome. erj;68/suppl_70/PA2874/F1 F1 F1 Conclusions: Higher CKM syndrome stages were associated with increased risk of adverse outcomes in bronchiectasis patients.

Background: Multidrug-resistant Pseudomonas aeruginosa (MDR-PA) is a common colonizer in bronchiectasis patients, associated with worse clinical outcomes. This study aimed to investigate the epidemiology, risk factors, and clinical impacts of MDR-PA colonization among bronchiectasis patients in Hong Kong. Methods: This territory-wide retrospective cohort study included adult bronchiectasis patients colonized with Pseudomonas aeruginosa from 2014 to 2023 using the Clinical Data Analysis and Reporting System (CDARS) of the Hospital Authority, Hong Kong. MDR-PA prevalence and associated factors were analyzed. Negative binomial regression with the log of follow-up time as an offset was used to assess the association between MDR-PA colonization and hospitalization-required exacerbations. Results: Among 5,765 bronchiectasis patients colonized with Pseudomonas aeruginosa, 220 patients had MDR-PA colonization, corresponding to an overall prevalence of 3.82%. In the multivariable logistic regression model, MDR-PA colonization was associated with proton pump inhibitor (PPI) use [adjusted odds ratio (aOR) =1.74, 95% confidence interval (CI): 1.26–2.39], inhaled corticosteroid (ICS) use (aOR =1.41, 95% CI: 1.01–1.98), macrolide therapy (aOR =2.12, 95% CI: 1.56–2.88), and hospitalized exacerbation episodes (aOR =1.09, 95% CI: 1.07–1.11). In the negative binomial regression model, MDR-PA colonization was independently associated with a higher frequency of hospitalization-required exacerbations (adjusted incidence rate ratio =2.07, 95% CI: 1.69–2.52, PConclusions: MDR-PA colonization was uncommon but clinically important among bronchiectasis patients colonized with Pseudomonas aeruginosa in Hong Kong. Medication exposure, particularly PPI, ICS and macrolide use, were associated with MDR-PA colonization. MDR-PA colonization was strongly associated with hospitalization-required exacerbations, supporting the need for early identification of high-risk patients and timely antimicrobial management.

Background: Co-existing asthma and diabetes mellitus (DM) are common, and there has been a debate on whether glucagon-like peptide-1 (GLP-1)-based therapies, such as GLP-1 receptor agonists (GLP-1RA) and inhibitors of dipeptidyl peptidase-4 (DPP-4i), confer benefits in these patients due to their anti-inflammatory effects in chronic inflammatory diseases. Methods: A territory-wide retrospective cohort study was conducted in Hong Kong among adult patients with co-existing asthma and DM to examine the impact of add-on GLP-1RA or DPP-4i on asthma exacerbations, ranging from mild exacerbations managed in outpatient settings to severe exacerbations requiring hospitalization. Adult patients were prescribed DPP-4i or GLP-1RA in year 2018 and for at least 6 months in Hospital Authority of Hong Kong were included. These patients were followed till 31st December 31, 2023. Propensity score matching was performed using optimal full matching, which is a sub-classification-based approach in which treated and control subjects are assigned to matched subclasses. Results: A total of 3295 patients with both asthma and DM, 3193 treated with DPP-4i and 102 treated with GLP-1RA, were included in the study. There were 1191 (36.1%) male patients with a mean age of 68.0 ± 14.2 years. There were 2531 (76.8%) patients with moderate-to-severe asthma according to Global Initiative for Asthma (GINA) Steps 3 to 5. GLP-1RA-treated patients had significantly lower risks of hospitalized asthma exacerbation (Average Treatment Effect on the Treated (ATT) Mean Ratio of 0.513, p < 0.001), ad hoc outpatient visits with OCS (ATT Mean Ratio of 0.343, p = 0.005), emergency visits (ATT Mean Ratio of 0.378, p = 0.009), and all asthma exacerbations (ATT Mean Ratio of 0.419, p < 0.001) compared with the DPP-4i group. Conclusion: GLP-1RA, compared with DPP-4i, as an add-on treatment for patients with co-existing DM and asthma was associated with a lower risk of asthma exacerbation. The use of GLP-1RA among diabetic patients with comorbid asthma may be considered though validation in clinical trials is needed.

Chronic cardiopulmonary, metabolic, and renal diseases represent an immense global health burden, yet access to organ-specific diagnostics remains limited outside of hospitals. Most clinical assessments rely on imaging or laboratory testing that is costly, infrastructure-dependent, and impractical for large-scale or longitudinal monitoring in community settings. Here, we introduce VitoCheck, a compact, user-friendly electrical impedance tomography (EIT) platform that provides non-invasive evaluation of lung, heart, liver, and kidney function within minutes. We first demonstrate system stability, spatial specificity, and spectral sensitivity through controlled phantom studies. We then validate VitoCheck in clinical cohorts by demonstrating accurate EIT-based predictions of standard diagnostic metrics, including spirometry-derived forced expiratory volumes, echocardiography-derived ejection fraction, ultrasound-derived liver fat scores, and blood serum-derived kidney filtration. User feedback further highlights the rapid scan workflow that supports deployment by non-specialists in decentralized environments. By combining portable and easy-to-use hardware with quantitative organ health analytics, VitoCheck enables scalable screening and proactive disease management for use in remote and out-of-clinic care.

Asthma is a prevalent chronic respiratory disease that affects individuals across all age groups worldwide. It is characterized by airway inflammation, bronchial hyperresponsiveness, and variable airflow obstruction, which can lead to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing. The age at which asthma first manifests play a crucial role in determining its underlying pathophysiology, clinical presentation, and management strategies. Broadly, asthma is classified into two categories based on age of onset: childhood-onset asthma and adult-onset asthma. Childhood-onset asthma typically begins during early childhood and often has a strong allergic component, whereas adult-onset asthma may develop later in life and can sometimes be associated with different triggers or comorbidities. These distinctions are important because they influence the disease’s clinical course, response to treatment, and long-term prognosis. Recognizing these differences allows for more targeted and effective management approaches tailored to each patient’s specific needs. This review aims to provide a comprehensive overview of childhood-onset asthma, including its underlying pathophysiology, diverse phenotypes, clinical features, diagnostic tools, and current treatment approaches. Special attention will be given to how childhood asthma evolves as patients grow older, including the transition from childhood to adulthood. Understanding these aspects is vital for optimizing management and improving outcomes for individuals affected by this chronic disease. By examining the unique features of childhood-onset asthma, healthcare providers can tailor interventions more effectively and anticipate potential challenges during the transition into adult care. Ultimately, a thorough knowledge of these differences can lead to better personalized treatment plans and improved quality of life for patients.