Associations between size-fractioned particulate matter and left ventricular voltage: A panel study among healthy young adults in southern China

Exposure to ambient air pollution is consistently associated with increased cardiovascular morbidity and mortality; however, the underlying pathophysiologic mechanisms remain unclear. High left ventricular voltage has been related to cardiac dysfunction. Therefore, this study aimed to investigate the association between longitudinal exposure to size-fractioned particulate matter (PM) and left ventricular voltage (assessed as the sum of the voltages of the R-wave in lead V5 [RV5] and S-wave in lead V1[SV1]) among 88 healthy, young Chinese adults. We collected weekly 12-lead electrocardiogram (ECG) and serum biomarkers from each participant five times over 35 days. The fixed point, real-time, mass concentrations of particles with aerodynamic diameters of <= 2.5 mu m (PM2.5), PM1, PM0.5, and number concentrations of particles with aerodynamic diameters of <= 0.2 mu m (PNC0.2), PNC0.1, and PNC0.03 were monitored in the catchment area, and linear mixed-effect models were used to estimate the associations between the size-fractioned PM exposure and ECG indices. The results showed that there was a significant association between higher size-fractioned PM levels and higher RV5+SV1 voltage within 24 h of exposure. We detected increases in the RV5+SV1 voltage of 0.060, 0.058, 0.090, 0.084, and 0.077 mV per interquartile range (IQR) PM2.5 (45.92 mu g/m(3); 95% confidence interval [CI] = 0.003, 0.117), PM1 (43.51 mu g/m(3); 95% CI = 0.003, 0.113), PNC0.2 (14.92 x 103 particles/cm(3); 95% CI = 0.017, 0.163), PNC0.1 (12.79 x 10(3) particles/cm(3); 95% CI = 0.004, 0.163), and PNC0.03 (5.43 x 10(3) particles/cm(3); 95% CI = 0, 0.153), respectively. The associations between the RV5+SV1 voltage and size-fractioned PM exposure were stronger among participants with greater serum concentrations of monocyte chemoattractant protein-1, soluble CD40 ligand, plasminogen activator inhibitor-1, and total cholesterol, and lower high-density lipoprotein cholesterol levels. Exposure to various PM size fractions (PNC0.03-PNC0.2, and PM0.5-PM2.5) may increase the left ventricular voltage among healthy young adults, and the effects may be modified by inflammation, coagulation, and lipid biomarkers.

Automated summary

The study found a significant association between higher levels of size-fractioned particulate matter (PM) and higher left ventricular voltage after exposure, indicating a potential adverse impact on cardiovascular health. Additionally, this association was particularly strong among individuals with specific inflammatory, coagulation, and lipid biomarkers, suggesting that these factors may modify the effects of PM exposure on heart health.