ABSTRACT:
Southeast Asia is undergoing rapid industrialization and urban expansion, often accompanied by deteriorating environmental quality. While public health strategies in the region have traditionally prioritized tobacco control as the dominant intervention for respiratory health, ambient air pollution—particularly fine particulate matter (PM2.5)—has emerged as a growing and underrecognized threat. This study aims to examine the evolving epidemiological landscape of chronic respiratory disease mortality in Southeast Asia by comparing the attributable burden of ambient particulate matter pollution and tobacco smoking over the past decade. We conducted a population-based ecological analysis using data from the Global Burden of Disease (GBD) study for 11 Southeast Asian countries between 2014 and 2024. Age-standardized mortality rates (ASMR) for chronic respiratory diseases, primarily chronic obstructive pulmonary disease (COPD), were extracted. Mortality burdens were stratified by two major risk factors: ambient particulate matter pollution and smoking. Temporal trends and relative rates of change were analyzed to assess shifts in dominant mortality drivers. The analysis reveals a concerning regional transition. While smoking-attributable mortality from chronic respiratory diseases has plateaued or modestly declined in several countries following tobacco control measures, mortality attributable to ambient PM2.5 exposure has remained persistently high or increased, particularly in rapidly urbanizing settings such as Jakarta, Bangkok, and Hanoi. Among elderly populations and urban residents, the contribution of ambient air pollution to respiratory mortality is increasingly comparable to that of tobacco smoking. These findings indicate that Southeast Asia is experiencing a respiratory health transition in which environmental exposure is emerging as a critical determinant of chronic respiratory mortality. Current respiratory health strategies that predominantly emphasize smoking cessation are insufficient to address this shifting risk profile. Effective prevention now requires urgent, cross-sectoral policies to reduce ambient air pollution, positioning clean air as a fundamental and non-negotiable public health intervention in the region.