The HKUMed researchers indicated that sputum analysis and blood counts at various time points can be used to accurately predict the risk of acute COPD exacerbations. (From left: Dr Samuel Chan Shung-kay, Dr Herbert Kwok Wang-chun, and Dr James Ho Chung-man)
In conjunction with World Chronic Obstructive Pulmonary Disease (COPD) Day, organised by the World Health Organisation and the Global Initiative for Chronic Obstructive Lung Disease (GOLD), a research team from the LKS Faculty of Medicine at the University of Hong Kong (HKUMed) has highlighted recent advances in understanding and managing COPD, particularly in relation to its exacerbations. The key findings indicate that patients' risk profiles can be assessed by measuring blood eosinophil counts at various time points and the isolation of Pseudomonas aeruginosa in sputum, which can facilitate personalised treatment.
COPD is one of the most common chronic diseases both locally and worldwide, placing a significant burden on patients and healthcare systems. Cigarette smoking is the primary cause of COPD, and its progression can lead to irreversible lung damage. In addition to the persistent symptoms, acute COPD exacerbation can result in hospitalisation and a rapid decline in lung function. This underscores the importance of prevention, early detection, and precise and effective management, which aligns with this year's World COPD theme: 'Short of Breath, Think COPD'.
Blood counts betray COPD exacerbation risks
The HKUMed research team reviewed local research advances over the past year, focusing on methods to predict acute COPD exacerbations. A key finding indicates that measuring blood eosinophil counts—a specific type of white blood cell—can help identify patients at risk of acute COPD exacerbations. While international guidelines recommend measuring eosinophil levels at a single time point, the team found that variability of blood eosinophil counts between stable periods and acute exacerbations was associated with a higher risk of future exacerbations [link to publication].
'These findings suggest that patients' risk profiles could be stratified by measuring blood eosinophil counts at different time points, both during stable state and at the time of exacerbation, which can provide a more accurate prediction of exacerbation risk,' said Dr Herbert Kwok Wang-chun, Clinical Assistant Professor, Department of Medicine, School of Clinical Medicine, HKUMed, who led the study.
Bacteria in sputum linked to COPD exacerbation risks
In addition to blood parameters, sputum analysis can be used to predict acute COPD exacerbations. The findings reveal that approximately 10% of COPD patients have Pseudomonas aeruginosa colonisation in their airways, as detected through sputum analysis. This bacterial presence significantly elevates the risk of future exacerbations, underscoring the importance of including sputum analysis in clinical management for COPD patients.
The newly released Global Initiative for Chronic Obstructive Lung Disease Report 2026 once again underscores the importance of acute exacerbations and introduces revised patient classification criteria. In the 2025 edition, patients who experienced at least two moderate exacerbations or one severe exacerbation in the previous year were classified as high risk. In contrast, the 2026 edition redefines high-risk patients to include those with at least one moderate exacerbation in the previous year. This update highlights the importance of exacerbations in COPD management and reminds clinicians to factor in every exacerbation when developing treatment plans. Early identification of high-risk patients is essential for developing effective therapeutic strategies.
Dr Herbert Kwok said, 'Our team is actively pursuing further research into COPD phenotyping and personalised treatment. We are also leading a multi-national multi-centre study involving eight countries and regions in the Asia-Pacific to further refine personalised treatment strategies for COPD.'
'Through these advancements, we aim to enhance understanding of COPD and its exacerbations, which are both treatable and preventable,' added Dr Kwok.
About the research team
The research was led by Dr Herbert Kwok Wang-chun, Clinical Assistant Professor in the Department of Medicine, School of Clinical Medicine, HKUMed. Other HKUMed collaborators include Dr James Ho Chung-man, Clinical Associate Professor, and Dr Samuel Chan Shung-kay, Honorary Clinical Assistant Professor, both from the same department.
