Fig. 3
Exposure–response curves for the relationship between individual time-weighted average exposure to PM2.5 and PM10 and carotid atherosclerosis. A and B demonstrated the trend for the risk of carotid atherosclerosis with the increasing level of one- and two-year average exposure to PM2.5, respectively. C and D described the exposure–response relationship between one- and two-year average exposure to PM10 and the risk of carotid atherosclerosis. PM2.5, particulate matter with aerodynamic diameter < 2.5 μm; PM10, particulate matter with aerodynamic diameter < 10 μm; HR, hazard ratio