Chronic obstructive pulmonary disease (COPD) is a major cause of illness and death globally. While tobacco smoking has long been known as the primary risk factor for COPD, it is now acknowledged that non-smokers constitute between one-fourth and one-third of all COPD cases. This highlights the importance of recognizing additional risk factors beyond smoking.
Risk factors for COPD in non-smokers can include genetic predispositions, long-term asthma, exposure to secondhand smoke, outdoor air pollution from traffic and other sources, biomass smoke, occupational hazards, recurrent respiratory infections in early childhood, pulmonary tuberculosis, and low socioeconomic status. Additionally, impaired lung growth during childhood, resulting in smaller lung size and lower baseline lung function, is linked to an increased risk of developing COPD.
The potential mechanisms for the development of COPD in never-smokers include inflammation, oxidative stress, lung remodeling, and accelerated lung aging. Compared to smokers with COPD, never-smokers typically experience milder chronic respiratory symptoms, minimal or no emphysema, less severe airflow limitation, and fewer comorbidities. However, they can still frequently suffer from exacerbations.
To enhance outcomes for at-risk populations, it is crucial to implement effective education, public health interventions, and early detection strategies for the prevention, diagnosis, and timely management of COPD in never-smokers. Non-smokers with symptoms should be included in clinical surveillance and screening programmes for COPD.
While smoking remains the predominant risk factor for COPD, a significant portion of cases occur in non-smokers, underscoring the importance of recognizing other contributing factors. Effective education, public health initiatives, and early detection are critical for managing COPD in these populations. By including symptomatic non-smokers in clinical surveillance and screening efforts, we can improve prevention, diagnosis, and treatment outcomes, ultimately enhancing the quality of life for all individuals affected by COPD.
[The writer is a consultant “ Interventional Pulmonology, Manipal Hospital, Goa]
