The effect of particulate matter size on cardiovascular health in Taipei Basin, Taiwan

Background: Although the overall effect of particulate matter (PM) on cardiovascular disease (CVD) has been previously documented, the effect of different PM sizes (PM₁₀, PM_2.5-10 and PM_2.5) has not been well studied. This study estimates the effect of different PM sizes on the incidence of CVD in Taipei, Taiwan.

Methods: We collected outpatients with CVD from 2006 to 2010 and data on the concentrations of air pollutants such as PM₁₀, PM_2.5-10, PM_2.5, sulfur dioxide, carbon monoxide, nitrogen dioxide, and ozone. A Distributed Lag Non-linear Model (DLNM) was used to explore the effect of different PM sizes on CVD risk.

Results: In high air pollution events, PM_2.5 was significantly associated with elevated risk (4.9%) [95% confidence interval (CI): 1.010-1.089] for CVD with increasing interquartile range (IQR) in single air pollutant model. PM_2.5-10 and PM₁₀ did not show a significant positive association with CVD in this study. After adjusting for other air pollutants such as SO₂, CO, NO₂, and O₃, the estimated effect of PM_2.5 only decreased 0.2%. Moreover, patients under 40 years old did not show a significant association between PM_2.5 and CVD.

Conclusion: This study demonstrates that only PM_2.5 is significantly positively correlated with the number of daily outpatient visits for CVD during high air pollution events.