Associations of preconception air pollution exposure with growth trajectory in young children: A prospective cohort study

Jiawen Liao; Weili Yan; Yi Zhang; Kiros Berhane; Wu Chen; Zhenchun Yang; Chenyu Qiu; Yihui Ge; Zhipeng Bai; Bin Han; Jia Xu; Yong-Hui Jiang; Frank D Gilliland; Junfeng Jim Zhang; Guoying Huang; Zhanghua Chen

doi:10.1016/j.envres.2024.120665

Associations of preconception air pollution exposure with growth trajectory in young children: A prospective cohort study

Environ Res. 2024 Dec 18:267:120665. doi: 10.1016/j.envres.2024.120665. Online ahead of print.

Authors

Jiawen Liao¹, Weili Yan², Yi Zhang², Kiros Berhane³, Wu Chen¹, Zhenchun Yang¹, Chenyu Qiu¹, Yihui Ge⁴, Zhipeng Bai⁵, Bin Han⁵, Jia Xu⁵, Yong-Hui Jiang⁶, Frank D Gilliland¹, Junfeng Jim Zhang⁴, Guoying Huang⁷, Zhanghua Chen⁸

Affiliations

¹ Department of Population and Public Health Sciences, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA.
² Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defect, Shanghai, China.
³ Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA.
⁴ Division of Environmental Science and Policy, Nicholas School of the Environment, Duke University, Durham, NC, USA.
⁵ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China.
⁶ Department of Genetics, Neuroscience, and Pediatrics, Yale University School of Medicine, New Haven, CT, USA.
⁷ Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defect, Shanghai, China. Electronic address: gyhuang@shmu.edu.cn.
⁸ Department of Population and Public Health Sciences, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA. Electronic address: zhanghuc@usc.edu.

PMID: 39706320
DOI: 10.1016/j.envres.2024.120665

Abstract

Gestational air pollution exposure was associated with childhood obesity. However, little is known about the effect of air pollution exposure during the preconception period, a critical window when environmental exposures may affect body growth trajectory and increase obesity risk. We conducted a population-based prospective cohort study of preconception women and their newborn children followed until 2 years old from metropolitan Shanghai, China to investigate the impact of preconception air pollution on childhood weight and body mass index (BMI) growth trajectories. Exposures to PM_2.5, PM₁₀, and NO₂ during 3 months before conception and each trimester of pregnancy were estimated using high-resolution spatiotemporal models matched at residential addresses. Children's weight and BMI were assessed postnatally every three months. Multivariate and longitudinal models with piecewise linear mixed effects were used to examine the relationship between preconception air pollution and child growth trajectories of weight, BMI, and standardized BMI (BMIZ). The study population comprised 26,714 women in the baseline enrolled in preconception clinics and 5,834 children reached 2 years included in the analysis with 34,398 longitudinal weight and height measurements. One interquartile range (IQR) increase in preconception PM_2.5 (16.2 μg/m³) was associated with a 0.078 (95% confidence interval (CI): 0.002-0.154, p = 0.04) increase in attained BMIZ and 1 IQR increase of PM₁₀ (21.1 μg/m³) were associated with an 0.093 (95% CI: 0.002-0.184, p = 0.04) kg/m² increase in attained BMI, respectively, at the age of two years, after controlling for individual covariates and gestational air pollution exposure. Higher weight, BMI, and BMIZ growth rates during 6-24 months of life were also associated with higher preconception NO₂ and PM exposure. Males and children born to mothers less than 35 years old or with overweight/obesity status were more affected by preconception air pollution exposure on weight growth. The 3-month preconception period was a critical time window for air pollution exposure.

Keywords: Air pollution; Body-mass-index (BMI); Childhood obesity; DOHaD; Excessive growth; Preconception.