Proposed Etiotypes for Chronic Obstructive Pulmonary Disease: Controversial Issues

Abstract

The 2023 Global Initiative for Chronic Obstructive Lung Disease (GOLD) revised thedefinition of chronic obstructive pulmonary disease (COPD) to broadly include a varietyof etiologies. A new taxonomy, composed of etiotypes, aims to highlight the heterogeneityin causes and pathogenesis of COPD, allowing more personalized managementstrategies and emphasizing the need for targeted research to understand and manageCOPD better. However, controversy arises with including some diseases under the umbrellaterm of COPD, as their clinical presentations and treatments differ from classicalCOPD, which is smoking-related. COPD due to infection (COPD-I) and COPD due toenvironmental exposure (COPD-P) are classifications within the new taxonomy. Somedisease entities in these categories show distinct clinical features and may not benefitfrom conventional COPD treatments, raising questions about their classification asCOPD subtypes. There is also controversy regarding whether bronchiectasis with airflowlimitations should be classified as an etiotype of COPD. This article discusses controversialissues associated with the proposed etiotypes for COPD in terms of COPD-I, COPD-P, and bronchiectasis. While the updated COPD definition by GOLD 2023 is amajor step towards recognizing the disease’s complexity, it also raises questions aboutthe classification of related respiratory conditions. This highlights the need for furtherresearch to improve our understanding and approach to COPD management.