Related Experiment Video
Updated: Aug 23, 2025

Measuring Carbon Content in Airway Macrophages Exposed to Carbon-Containing Particulate Matters
Published on: July 12, 2024
Effect of asthma, COPD, and ACO on COVID-19: A systematic review and meta-analysis
Yuka Uruma1, Toshie Manabe2,3, Yuji Fujikura4,5
1Nagoya City University Medical School, Aichi, Japan.
Insights
COVID-19 patients with asthma or COPD had varying prevalence rates. While asthma did not significantly impact mortality, chronic obstructive pulmonary disease (COPD) substantially increased COVID-19 patient mortality risk.
Area of Science:
- Respiratory Medicine
- Infectious Diseases
- Epidemiology
Background:
- Asthma, COPD, and ACO prevalence and mortality risks in COVID-19 patients are not well-defined.
- Understanding these comorbidities is crucial for managing COVID-19 patients.
Purpose of the Study:
- To assess the prevalence of asthma, COPD, and ACO in COVID-19 patients.
- To determine the mortality risks associated with these respiratory conditions in COVID-19 patients.
Main Methods:
- Systematic review and meta-analysis of 101 studies including 1,229,434 COVID-19 patients.
- Searched PubMed for eligible studies up to September 27, 2021.
- Stratified analysis conducted by country.
Main Results:
- Prevalence: Asthma 10.04%, COPD 8.18%, ACO 3.70%.
- Mortality risk: Asthma OR 0.89 (not significant), COPD OR 3.79 (significant).
- Highest asthma prevalence in France/UK; highest COPD prevalence in Netherlands/India.
Conclusions:
- COPD significantly increases mortality risk in COVID-19 patients.
- Asthma does not appear to significantly affect COVID-19 mortality.
- Geographical variations in prevalence may be linked to disease pathophysiology and healthcare policies.
Introduction:
The prevalence of asthma, chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap (ACO) in patients with COVID-19 varies, as well as their risks of mortality. The present study aimed to assess the prevalence of asthma, COPD, and ACO as comorbidities, and to determine their risks of mortality in patients with COVID-19 using a systematic review and meta-analysis.
Methods:
We systematically reviewed clinical studies that reported the comorbidities of asthma, COPD, and ACO in patients with COVID-19. We searched various databases including PubMed (from inception to 27 September 2021) for eligible studies written in English. A meta-analysis was performed using the random-effect model for measuring the prevalence of asthma, COPD, and ACO as comorbidities, and the mortality risk of asthma, COPD, and ACO in patients with COVID-19 was estimated. A stratified analysis was conducted according to country.
Results:
One hundred one studies were eligible, and 1,229,434 patients with COVID-19 were identified. Among them, the estimated prevalence of asthma, COPD, and ACO using a meta-analysis was 10.04% (95% confidence interval [CI], 8.79-11.30), 8.18% (95% CI, 7.01-9.35), and 3.70% (95% CI, 2.40-5.00), respectively. The odds ratio for mortality of pre-existing asthma in COVID-19 patients was 0.89 (95% CI, 0.55-1.4; p = 0.630), while that in pre-existing COPD in COVID-19 patients was 3.79 (95% CI, 2.74-5.24; p<0.001). France showed the highest prevalence of asthma followed by the UK, while that of COPD was highest in the Netherlands followed by India.
Conclusion:
Pre-existing asthma and COPD are associated with the incidence of COVID-19. Having COPD significantly increases the risk of mortality in patients with COVID-19. These differences appear to be influenced by the difference of locations of disease pathophysiology and by the daily diagnosis and treatment policy of each country.
More Related Videos
Related Concept Videos
Asthma: Pathogenesis and Management
Asthma is classified as allergic and non-allergic. Allergens such as dust mites, pollen, and pet dander trigger allergic asthma, while factors like cold air, intense emotions, or exercise can induce non-allergic asthma.
Asthma-II: Pathophysiology and Classification
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:
COPD: Management Using Bronchodilators and Corticosteroids
COPD: Pathogenesis and Clinical Features
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...
Asthma-III: Symptoms and Complications
Classification of Asthma
Asthma-IV: Diagnostic and Management
Clinical Assessment for Asthma:
This is the first step in diagnosing and managing asthma. It includes:

