Interaction between walkability and fine particulate matter on ischemic heart disease: A prospective cohort study in China

• Published in: Ecotoxicology and environmental safety 2025-01, Vol.290, p.117520, Article 117520
• Main Authors: Zhang, Jiayun, Shen, Peng, Wang, Yixing, Li, Zihan, Xu, Lisha, Qiu, Jie, Hu, Jingjing, Yang, Zongming, Wu, Yonghao, Zhu, Zhanghang, Lin, Hongbo, Jiang, Zhiqin, Shui, Liming, Tang, Mengling, Jin, Mingjuan, Tong, Feng, Chen, Kun, Wang, Jianbing
• Format: Article
• Language: English
• Subjects: Adult; Aged; Air Pollutants - analysis; Air Pollution - statistics & numerical data; China - epidemiology; Dose-response relationship; Environmental Exposure - statistics & numerical data; Female; Fine particulate matter; Humans; Interaction; Ischemic heart disease; Male; Middle Aged; Myocardial Ischemia - chemically induced; Myocardial Ischemia - epidemiology; Particulate Matter - analysis; Proportional Hazards Models; Prospective cohort study; Prospective Studies; Walkability; Walking
• ISSN: 0147-6513; 1090-2414; 1090-2414
• DOI: 10.1016/j.ecoenv.2024.117520

Previous studies have suggested that neighborhoods characterized by higher walkability are related to a reduced risk of ischemic heart disease (IHD), whereas exposure to PM2.5 is positively associated with risk of IHD. Nevertheless, their joint impact on IHD warrants further investigation. This prospective cohort study was performed in Yinzhou, Ningbo, China, comprising 47,516 participants. Individual-level walkability and PM2.5 were evaluated using a commercial walkability database and a land use regression (LUR) model, respectively. Hazard ratios (HRs) and 95 % confidence intervals (95 % CIs) were calculated using two Cox proportional hazards models: one based on two-year average PM2.5 levels prior to baseline, and the other incorporating time-varying PM2.5 assessed on a monthly scale. Dose-response relationships were explored using restricted cubic spline (RCS) functions. Interactions on both additive and multiplicative scales were assessed via relative excess risk due to interaction (RERI) and likelihood-ratio tests. Joint effects were explored and visualized using a 3D wireframe plot. Over a median follow-up of 5.14 years, 1735 incident cases of IHD were identified. Adjusted HRs (95 % CIs) were 1.56 (1.34–1.81) per 10 μg/m3 increase in PM2.5 and 0.96 (0.94–0.98) per 10-unit increase in walkability, with both exposures exhibiting non-linear dose-response relationships. Walkability and PM2.5 were positively correlated (rs = 0.12, P