Beyond Smoking: Exploring Etiotypes of Chronic Obstructive Pulmonary Disease (COPD) Using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2023 Classification

Background and objective Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a heterogeneous condition with multiple etiologies beyond smoking. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2023 guidelines define seven distinct COPD etiotypes based on underlying risk factors. This study aimed to identify the distribution of these GOLD-defined COPD etiotypes in an Indian tertiary care cohort and examine their association with disease severity, symptom burden, and exacerbation frequency. Methods and results In this cross-sectional record-based study, 1,452 medical records (Jan 2020-May 2023) were screened, identifying 86 patients with spirometry-confirmed COPD. Etiotypes were assigned per GOLD 2023 definitions. Among these patients, 61.6% had multiple etiotypes. Male patients predominantly exhibited smoking- and pollution-related COPD, while all female patients had pollution-related COPD. A significant association was found between multiple etiotypes and greater spirometric severity (p = 0.046), though no significant links were observed with symptom burden or exacerbation frequency. Conclusion COPD in the Indian population demonstrates diverse and often overlapping etiological profiles, with non-smoking exposures such as biomass and incense smoke playing a major role, particularly in women. The presence of multiple etiotypes correlates with worse lung function, underscoring the importance of population-specific phenotyping and routine spirometry for optimal COPD management.