Liu Ping, Zhang Zhaoliang, Luo MingZhong
The Second People's Hospital of Shanxi Province, Taiyuan, Shanxi, China.
The Affiliated YiXing Hospital of Jiangsu University, Yixing, Jiangsu, China.
Front Public Health. 2025 Apr 2;13:1551851. doi: 10.3389/fpubh.2025.1551851. eCollection 2025.
This study aimed to determine the relationships between mixed exposure to six air pollutants, namely, particulate matter with an aerodynamic diameter of 2.5 micrometers or less (PM), PM with an aerodynamic diameter of 10 micrometers or less (PM), sulfur dioxide (SO), nitrogen dioxide (NO), cobalt (CO) and ozone (O), and insulin resistance (IR) indices in Chinese middle-aged and older populations.
A total of 2,219 participants from the China Health and Retirement Longitudinal Study (CHARLS), who are followed from 2011 to 2015, were included. Surface air pollutant concentration data were obtained from the China High Air Pollutants (CHAP) database. Multivariable linear regression analysis was used to examine the longitudinal associations between different air pollutants and various IR indices. Additionally, Bayesian kernel machine regression (BKMR), weighted quantile sum (WQS) regression, and quantile-based g computation (Qgcomp) were further utilized to assess the mixed effects of the six air pollutants.
Fully adjusted linear models revealed that increases in the levels of the six air pollutants (in μg/m) were associated with higher triglyceride-glucose-body mass index (TyG-BMI; Beta = 0.027-0.128), triglyceride-glucose-waist circumference (TyG-WC; Beta = 0.155-0.674), and metabolic score for insulin resistance (METS-IR; Beta = 0.001-0.029) values during the four-year follow-up period. Further mixture analysis indicated that combined exposure to the six air pollutants had a significant cumulative effect on the increases in these three IR indices. Among the pollutants, NO and O were identified as the primary contributor to the cumulative effect. The result of mediation analysis supported the mediating role of BMI in the relationship between air pollution and IR (mediation proportion: 49.1%-93.5%). The results from both subgroup analysis and sensitivity analysis supported the detrimental effects of air pollution on IR.
Both individual and mixed exposures to air pollution were significantly associated with IR in Chinese middle-aged and older individuals, with our study providing new evidence.
本研究旨在确定中国中老年人群中六种空气污染物混合暴露，即空气动力学直径小于或等于2.5微米的颗粒物（PM）、空气动力学直径小于或等于10微米的颗粒物（PM）、二氧化硫（SO）、二氧化氮（NO）、一氧化碳（CO）和臭氧（O）与胰岛素抵抗（IR）指数之间的关系。
纳入了中国健康与养老追踪调查（CHARLS）中2011年至2015年期间随访的2219名参与者。地面空气污染物浓度数据来自中国高空气污染物（CHAP）数据库。采用多变量线性回归分析来检验不同空气污染物与各种IR指数之间的纵向关联。此外，还进一步利用贝叶斯核机器回归（BKMR）、加权分位数和（WQS）回归以及基于分位数的g计算（Qgcomp）来评估六种空气污染物的混合效应。
完全调整后的线性模型显示，在四年随访期间，六种空气污染物水平（以μg/m计）的升高与更高的甘油三酯-血糖-体重指数（TyG-BMI；β=0.027-0.128）、甘油三酯-血糖-腰围（TyG-WC；β=0.155-0.674）以及胰岛素抵抗代谢评分（METS-IR；β=0.001-0.029）值相关。进一步的混合分析表明，六种空气污染物的联合暴露对这三种IR指数的升高具有显著的累积效应。在这些污染物中，NO和O被确定为累积效应的主要贡献者。中介分析结果支持BMI在空气污染与IR关系中的中介作用（中介比例：49.1%-93.5%）。亚组分析和敏感性分析的结果均支持空气污染对IR的有害影响。
在中国中老年个体中，空气污染的单独暴露和混合暴露均与IR显著相关，本研究提供了新的证据。
