Global burden of neonatal respiratory infections attributable to air pollution: a systematic analysis based on the global burden of disease 2021 study.

Neonatal respiratory infections (NRIs) remain a major cause of morbidity and mortality in the first 28 days of life, and air pollution is an important environmental risk factor. However, the global, regional, and temporal burden of NRIs attributable to air pollution has not been comprehensively characterized. Using data from the Global Burden of Disease (GBD) Study 2021, this study quantified deaths and disability-adjusted life years (DALYs) from NRIs and their subcategories attributable to air pollution, including both ambient particulate matter pollution and household air pollution from solid fuel use. We further examined the global, regional, and socio-demographic index (SDI)-level distribution and temporal trends of these burdens. Data on deaths and disability-adjusted life years (DALYs) of neonatal respiratory infections (NRIs) attributable to air pollution from 1990 to 2021 were obtained from the GBD 2021 database. Temporal trends were assessed using Joinpoint regression, socioeconomic inequality was evaluated using the Slope Index of Inequality (SII) and Concentration Index (CIndex), frontier analysis was used to assess relative performance across development levels, and autoregressive integrated moving average (ARIMA) models were applied to project future trends. In 2021, air pollution contributed to 64,405 neonatal deaths and 5.8 million disability-adjusted life years (DALYs) from respiratory infections worldwide. Death and DALY rates declined significantly from 1990 to 2021, with an estimated annual percentage change (EAPC) of -3.84%. Lower respiratory infections accounted for the majority of the attributable burden, and male neonates consistently experienced higher mortality and DALY rates than females. Marked geographic and socioeconomic inequalities were observed, with the heaviest burden concentrated in low-SDI regions, particularly South Asia and Sub-Saharan Africa; household air pollution contributed a larger share in lower-SDI settings, whereas ambient particulate matter became relatively more prominent in more developed settings.

conclusionAlthough the global burden of neonatal respiratory infections attributable to air pollution has declined over the past three decades, substantial geographic and socioeconomic inequalities persist, with the heaviest burden concentrated in low-SDI settings. Coordinated strategies that combine air-quality improvement with strengthened maternal and neonatal health services are needed to further reduce this burden and promote health equity. WHAT IS KNOWN: • Neonatal respiratory infections (NRIs) remain an important cause of morbidity and mortality in the first 28 days of life. • Air pollution is an important environmental risk factor for respiratory health and increases the risk of respiratory infections in infants and young children. WHAT IS NEW: • From 1990 to 2021, the burden of NRIs attributable to air pollution showed an overall declining trend, but marked regional disparities persisted, with a substantially higher burden in low-SDI regions. • Globally, lower respiratory infections accounted for the largest share of NRIs attributable to air pollution, while the relative contributions of diff erent air-pollution sources varied substantially across SDI levels.