The impact of PM2.5 on children’s blood pressure growth curves: A prospective cohort study

Objective: The aim of this study was to explore the association between exposure to particulate matter with an aerodynamic diameter of 2.5 mm or less (PM2.5) and blood pressure (BP) levels in children and adolescents and to illustrate the impact of PM2.5 levels on BP growth curves in a cohort study. Methods: A longitudinal study was designed and included 4303 children (7617 BP measurements) living in the selected areas, and evaluations were conducted in 2014–2015 (visit 1) and followed up in 2019 (visit 2). Two-stage stratified cluster sampling was used to include urban–rural areas. A mixed linear regression model and mixed logistic regression model were used to analyze the effect of PM2.5 exposure on BP and the incidence of prehypertension and hypertension in children. Results: After adjusting for covariates, systolic blood pressure (SBP) (2.21 (95% CIs: 0. 81, 3.62), mmHg), diastolic blood pressure (DBP) (1.92 (95% CIs: 0.74, 3.11), mmHg), mean arterial pressure (MAP) (2.03 (95% CIs: 0.89, 3.17), mmHg) and heart rate (HR) (2.24 (95% CIs: 0.11, 4.37), beats/min) increased significantly in the fourth quartile of PM2.5 exposure levels compared with the first quartile (all P