Short-term effects of air pollution on pulse pressure among nonsmoking adults.

BACKGROUND: Previous studies on the effects of acute air pollution have focused primarily on blood pressure (BP).

METHODS: Our study enrolled 9238 nonsmoking adults over 30 years of age from 6 townships in Taiwan: 1 seaport, 1 urban, 1 industrial, and 3 rural. Using generalized additive models, we evaluated the associations between brachial BP and short-term exposure to 5 air pollutants: particulate matter with diameter <10 μm (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxide (NO(2)), carbon monoxide (CO), and ozone (O(3)).

RESULTS: After adjusting for individual and meteorologic factors, the systolic BP was decreased by all 5 pollutants, whereas the diastolic BP was increased by SO(2), NO(2), and O(3). The pulse pressure was consistently decreased by all 5 pollutants, with changes of -1.5 (95% confidence interval = -2.0 to -1.1), -0.6 (-0.9 to -0.4), -2.4 (-3.0 to -1.8), -1.2 (-1.6 to -0.9), and -1.4 (-1.8 to -0.9) mm Hg for interquartile range increases in 3-day lagged PM(10), SO(2), NO(2), carbon monoxide, and O(3), respectively. PM(10) exposure was more strongly associated with reduction of pulse pressure among men, persons >60 years of age, those with hypertension, and those living in the industrial township.

CONCLUSIONS: Short-term exposure to air pollution reduces pulse pressure. PM(10) in industrial emissions may contribute to pulse pressure changes. Age, sex, and hypertensive status may modify the effects of PM(10) on pulse pressure.