Liu Mao, Wang Pei-Hua, Ye Yun-Jie, Shang Li, Xia Yu-Ting, Wang Yang, Ding Zhen, Xu Yan
Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, 210009, China.
Environ Health. 2025 Apr 7;24(1):18. doi: 10.1186/s12940-025-01172-9.
Long-term exposure to particulate matter with aerodynamic diameter ≤ 2.5 μm (PM) are linked to thyroid nodules in adults, but epidemiological evidence in children and adolescents and adjustments for key confounders are lacking. This study aimed to explore the association between long-term exposure to PM and the prevalence of thyroid nodules in school-aged children and adolescents.
A cross-sectional study including 10,739 primary and junior high school students was conducted in Jiangsu Province, China, in 2021. Annual PM concentrations were estimated by a satellite based space-time model based on machine learning. Individual exposure concentrations were assigned according to the school addresses of the participants. High-resolution diagnostic ultrasound imaging was used to detect the thyroid nodules. After adjustment for covariates, the link between the two-year (2019-2020) average PM concentrations and thyroid nodules was estimated using a generalized linear mixed-effects model. The concentration-response (C-R) curves were smoothed using a restricted cubic spline function. Stratified analyses were performed to evaluate the modification effects of covariates on associations.
The average age of the 10,067 participants (51.9% boys) was 11 years, with a thyroid nodule prevalence of 30.5%. A non-linear positive correlation was found between the increase in prevalence of thyroid nodules and two-year average exposure concentration of PM. The C-R relationship curve between thyroid nodules and PM had a J-shaped structure with a threshold value of 39.7 µg/m. Following covariates adjustment, the odds ratio (OR) and 95% confidence interval (CI) linked to thyroid nodules were 1.515 (1.199, 1.915) for per standard deviation (SD) increase in two-year average PM concentrations (> 39.7 µg/m). The sex-specific associations found among adults were not observed in our stratified analyses.
Our findings demonstrated that long-term exposure to PM was associated with a higher prevalence of thyroid nodules in children and adolescents. Strategies that consistently reduce PM pollution levels to ease the burden of non-communicable diseases have important public health implications.
长期暴露于空气动力学直径≤2.5μm的颗粒物（PM）与成人甲状腺结节有关，但儿童和青少年的流行病学证据以及对关键混杂因素的调整尚缺乏。本研究旨在探讨长期暴露于PM与学龄儿童和青少年甲状腺结节患病率之间的关联。
2021年在中国江苏省进行了一项横断面研究，纳入10739名中小学生。基于机器学习的卫星时空模型估计年度PM浓度。根据参与者的学校地址分配个体暴露浓度。采用高分辨率诊断超声成像检测甲状腺结节。在对协变量进行调整后，使用广义线性混合效应模型估计两年（2019 - 2020年）平均PM浓度与甲状腺结节之间的关联。使用受限立方样条函数对浓度 - 反应（C - R）曲线进行平滑处理。进行分层分析以评估协变量对关联的修正作用。
10067名参与者（51.9%为男孩）的平均年龄为11岁，甲状腺结节患病率为30.5%。发现甲状腺结节患病率的增加与两年平均PM暴露浓度之间存在非线性正相关。甲状腺结节与PM之间的C - R关系曲线呈J形结构，阈值为39.7μg/m³。在对协变量进行调整后，两年平均PM浓度每增加一个标准差（SD）（>39.7μg/m³），与甲状腺结节相关的优势比（OR）及95%置信区间（CI）为1.515（1.199，1.915）。在分层分析中未观察到成人中发现的性别特异性关联。
我们的研究结果表明，长期暴露于PM与儿童和青少年甲状腺结节患病率较高有关。持续降低PM污染水平以减轻非传染性疾病负担的策略具有重要的公共卫生意义。
