Long-term exposure to ambient ozone and cardiovascular diseases: Evidence from two national cohort studies in China

Shuru Liang; Yumeng Chen; Xiaoli Sun; Xiaomei Dong; Guanhao He; Yudong Pu; Jingjie Fan; Xinqi Zhong; Zhiqing Chen; Ziqiang Lin; Wenjun Ma; Tao Liu

doi:10.1016/j.jare.2023.08.010

Long-term exposure to ambient ozone and cardiovascular diseases: Evidence from two national cohort studies in China

J Adv Res. 2023 Aug 23:S2090-1232(23)00226-6. doi: 10.1016/j.jare.2023.08.010. Online ahead of print.

Authors

Shuru Liang¹, Yumeng Chen², Xiaoli Sun³, Xiaomei Dong¹, Guanhao He¹, Yudong Pu⁴, Jingjie Fan⁵, Xinqi Zhong⁶, Zhiqing Chen¹, Ziqiang Lin¹, Wenjun Ma¹, Tao Liu⁷

Affiliations

¹ Department of Public Health and Preventive Medicine, School of Medicine, Jinan University, Guangzhou 510632, China; China Greater Bay Area Research Center of Environmental Health, School of Medicine, Jinan University, Guangzhou 510632, China.
² Affiliated Foshan Maternity & Child Healthcare Hospital, Southern Medical University, Foshan 528000, China.
³ Gynecology Department, Guangdong Women and Children Hospital, Guangzhou 511442, China.
⁴ Songshan Lake Central Hospital of Dongguan City, Dongguan 523808, China.
⁵ Department of Prevention and Health Care, Shenzhen Maternity & Child Healthcare Hospital, Southern Medical University, Shenzhen 518028, China.
⁶ Department of Neonatology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China.
⁷ Department of Public Health and Preventive Medicine, School of Medicine, Jinan University, Guangzhou 510632, China; China Greater Bay Area Research Center of Environmental Health, School of Medicine, Jinan University, Guangzhou 510632, China. Electronic address: gztt_2002@163.com.

PMID: 37625570
DOI: 10.1016/j.jare.2023.08.010

Abstract

Introduction: The health effects of ambient ozone have been investigated in many previous studies. However, the effects of long-term exposure to ambient ozone on the incidence of cardiovascular disease (CVD) remain inconclusive.

Objectives: To estimate the associations of long-term exposure to maximum daily 8-hours average ozone (MDA8 O₃) with the incidence of total CVD, heart disease, hypertension, and stroke.

Methods: This was a prospective cohort study, and the data was obtained from the China Health and Retirement Longitudinal Survey (CHARLS) implemented during 2011-2018 and the China Family Panel Studies (CFPS) implemented during 2010-2018. We applied a Cox proportional hazards regression model to evaluate the associations of MDA8 O₃ with total CVD, heart disease, hypertension, and stroke risks, and the corresponding population-attributable fractions (PAF) attributable to MDA8 O₃ were also calculated. All analyses were conducted by R software.

Results: The mean MDA8 O₃ concertation of all included participants in the CHARLS and CFPS were 51.03 part per billion (ppb) and 51.15 ppb, respectively. In the CHARLS including 18,177 participants, each 10 ppb increment in MDA8 O₃ concentration was associated with a 31% increase [hazard ratio (HR) = 1.31, 95% confidence interval (CI): 1.22-1.42] in the risk of incident heart disease, and the corresponding population-attributable fractions (PAF) was 13.79% [10.12%-17.32%]. In the CFPS including 30,226 participants, each 10 ppb increment in MDA8 O₃ concentration was associated with an increase in the risk of incident total CVD (1.07 [1.02-1.13]), and hypertension (1.10 [1.03-1.18]). The PAFs of total CVD, and hypertension attributable to MDA8 O₃ were 3.53% [0.82%-6.16%], and 5.11% [1.73%-8.38%], respectively. Stratified analyses showed greater associations in males, urban areas, and Southern China.

Conclusions: Long-term exposure to MDA8 O₃ may increase the incidence of CVD. Therefore, the policies that control O₃ and related precursors are persistently needed.

Keywords: Air pollution; Ambient ozone; Cardiovascular diseases; Cohort study; Disease burden.