From the Guidelines
Yes, Chronic Obstructive Pulmonary Disease (COPD) can develop in non-smokers.
Risk Factors for COPD in Non-Smokers
- Occupational exposures to organic and inorganic dusts, chemical agents, and fumes 1
- Indoor air pollution from biomass cooking and heating in poorly ventilated dwellings 1
- Air pollution 1
- Asthma 1
- A history of severe childhood respiratory infection 1
- HIV infection 1
- Tuberculosis 1
Key Points
- Never smokers with chronic airflow limitation have fewer symptoms, milder disease, and a lower burden of systemic inflammation compared to smokers with COPD 1
- Never smokers with chronic airflow limitation do not have an increased risk of lung cancer or cardiovascular comorbidities, but have an increased risk of other health issues 1
- Approximately 50% of patients developed COPD owing to an accelerated decline in FEV, while the other 50% developed COPD owing to abnormal lung growth and development 1
Evidence Summary
The Global Initiative for Chronic Obstructive Lung Disease (GOLD) reports that while cigarette smoking is the most well-studied COPD risk factor, epidemiologic studies demonstrate that nonsmokers may also develop chronic airflow limitation 1. The evidence suggests that non-smokers can develop COPD due to various risk factors, and it is essential to consider these factors in the diagnosis and management of COPD.
From the Research
COPD in Non-Smokers
- Chronic Obstructive Pulmonary Disease (COPD) can develop in non-smokers, with about half of all COPD cases worldwide attributed to non-tobacco-related risk factors 2.
- Non-smoking-related risk factors for COPD include air pollution, occupational exposures, poorly controlled asthma, environmental tobacco smoke, infectious diseases, and low socioeconomic status 2, 3.
- Impaired lung growth during childhood, caused by early-life exposures, is also associated with an increased risk of COPD in non-smokers 2.
Clinical Characteristics
- Non-smokers with COPD tend to have relatively mild chronic respiratory symptoms, little or no emphysema, milder airflow limitation, and fewer comorbidities compared to smokers with COPD 2, 4.
- However, exacerbations can still be frequent in non-smokers with COPD 2.
- COPD in non-smokers is more frequent in women and older ages, and is associated with a slightly higher prevalence of comorbidities 5.
Risk Factors and Pathogenesis
- The pathogenesis of COPD in non-smokers may involve inflammation, oxidative stress, airway remodelling, and accelerated lung ageing 2.
- Indoor and outdoor air pollution, poor socioeconomic status, and genetic factors may also play a role in the development of COPD in non-smokers 3.
- The prevalence of COPD among never smokers varies widely across nations, and more investigations are needed to understand the involved factors and their contributions to non-smoking-related COPD 3.