Air pollution and child stunting – a systematic review and meta-analysis

Abstract

TPS 722: Low and middle income countries: indoor air pollutants, Exhibition Hall, Ground floor, August 28, 2019, 3:00 PM - 4:30 PM Background/Aim: Air pollution is a major determinant of child health globally. Several studies have demonstrated associations between air pollution and childhood stunting, an important risk factor for early growth and development with lifelong health implications. While previous meta-analyses have reviewed these associations, until recently studies rarely included a specific focus on household air pollution (HAP) or pollution resulting from extreme air pollution episodes, both of which occur in regions with the greatest prevalence of stunting. We conducted a systematic review and meta-analysis of the peer-reviewed literature to assess the evidence of the associations. Methods: We systematically reviewed articles detailing associations between stunting, reported as height-for-age z-score, intrauterine growth restriction, or small for gestational age, and ambient air pollution (AAP) (e.g., PM2.5, PM10) or HAP, defined as the presence of household cooking with biomass fuels. Eligible studies had to be published in a peer-reviewed journal, include either primary or secondary data, and report at least one statistical measure. Results: The initial search identified 38 articles that met the inclusion criteria. A detailed screening excluded an additional 23 articles. The final list included 27 unique samples representing 18 countries and more than 1 million study participants. PM2.5 and PM10 exposures ranged from 10 to 72 and from 3 to 53 ug/m3 respectively. Significant risk estimates were found for those exposed to elevated concentrations of air pollution, ranging from 1.00 to 1.13 for AAP and from 1.21 to 1.90 for HAP. Conclusions: This review and meta-analysis identified up to a 13% and 90% increased risk of stunting in children exposed to increased levels of AAP and HAP respectively. This evidence suggests the importance of promoting clean air as part of an integrated approach to preventing stunting.