Associations between long-term particulate matter exposure and various metabolic syndrome components: Evidence from a prospective cohort study in Eastern China

Abstract

Epidemiological studies have suggested that exposure to particulate matter (PM) may increase the risk of developing metabolic syndrome (MetS). However, evidence on the long-term effects of PM exposure on the incidence of individual MetS's components remain limited and inconsistent. This knowledge gap highlights the need for further research to clarify the potential role of PM in the development and progression of MetS over extended periods. Follow-up data collected from a cohort in Eastern China, encompassing 44,720 individuals between 2014 and 2021, were utilized. Residential exposures to fine particles (PM_2.5) and inhalable particles (PM₁₀) for each participant were estimated using a random forest model with a spatial resolution of 1 × 1 km. The generalized estimating equations (GEE) model was employed to assess the associations of long-term PM exposures with incident MetS and its components, as well as with continuous metabolic indicators related to MetS. For each 10 μg/m³ increase in annual average concentration of PM_2.5, there were significant increases in the incidence of MetS (Relative risk: 1.17, 1.10–1.26), elevated triglycerides (TG) (1.17, 1.10–1.24), decreased high–density lipoprotein cholesterol (HDL-C) (1.18, 1.11–1.27), elevated fasting blood glucose (FBG) (2.05, 1.94–2.16), and elevated blood pressure (BP) (1.30, 1.17–1.44). The RR associated with PM₁₀ were smaller compared to PM_2.5 but still statistically significant. The analyses of continuous metabolic indicators indicated that long-term exposure to PM was positively associated with FBG and systolic BP, and inversely associated with HDL-C. This cohort study provides valuable evidence of the increased risk of MetS and its components associated with long-term PM exposure in areas with high pollution levels.