Association between PM2.5 components and electrocardiogram abnormalities among elderly individuals: a longitudinal study in Guangzhou, China

Fine particulate matter (PM 2.5 ) is linked with cardiovascular diseases (CVD), however, its association with electrocardiogram (ECG) abnormality, a prognostic indicator of CVD, remains largely unknown, especially different chemical components of PM 2.5 . This study aimed to investigate the longitudinal associations of long-term exposure to PM 2.5 and its chemical constituents with electrocardiogram abnormalities among elderly individuals in Guangzhou, China. The study was based on a survey of elderly people in the communities of Guangzhou from 2018 to 2022. Bilinear interpolation and residential addresses were used to ascertain annual averages of PM 2.5 and its components prior to ECG abnormalities. The generalized estimation equations (GEE) models were used to evaluate the association with ECG abnormalities. 215,073 participants were included in this study. Each participant received at least one electrocardiogram examination, with a total of 691,990 recordings. PM 2.5 and its five components (sulfate, nitrate, ammonium, organic matter, and black carbon) were significantly associated with elevated risks of ECG abnormalities. For PM 2.5 , odds ratio (OR) of ECG abnormalities per interquartile range (IQR) increase was 1.029 (95% confidence interval [CI]: 1.020–1.037), among its components was the highest for ammonium (OR:1.070, 95% CI: 1.062–1.078), followed by nitrate (OR:1.058, 95% CI: 1.050–1.065), sulfate (OR:1.047, 95% CI: 1.040–1.054), black carbon (OR:1.034, 95% CI: 1.027–1.042) and organic matter (OR:1.030, 95% CI: 1.022–1.037). Our study provides evidence that PM 2.5 and its components might lead to a greater risk of ECG abnormalities, underscoring the clinical value of ECG as an early indicator of potential reversible risks in the cardiovascular system. Strategies that target reducing PM 2.5 pollution might improve the health outcomes of elderly people with ECG abnormalities.