Background: Air pollution is a well-described environmental factor with
evidence suggesting a firm association with cardiovascular diseases. The
purpose of this study was to determine the association of exposure to
gaseous air pollutants on atherosclerosis burden.
Methods: 1955 inhabitants of the Corinthia region, aged 40 years or
older, underwent clinical and biochemical assessment as well as carotid
ultrasonography to evaluate carotid intima-media thickness (cIMT) and
plaque burden. Analyzers recording time series concentration of CO, NO2,
and SO2 were located at 4 different open sites (Regions 1, 2, 3 and 4)
based on their proximity to industries, highways or shipyards.
Results: A higher concentration of CO, NO2, and SO2 was observed in
Region 4 compared to the other regions. Mean cIMT (Region 1: 0.93 +/-
0.24 mm; Region 2: 0.96 +/- 0.40 mm; Region 3: 0.94 +/- 0.39 mm; Region
4: 1.14 +/- 0.55 mm, p < 0.001), maximum cIMT (p < 0.001) as well as
carotid plaque burden (Region 1: 13.3%; Region 2: 18.8%; Region 3:
22.4%; Region 4: 38.6%, p < 0.001) were significantly higher in
individuals of Region 4. Inhabitants of Region 4 had also higher levels
of C reactive protein (Region 1: 4.56 +/- 4.85 mg/l; Region 2: 3.49 +/-
4.46 mg/l; Region 3: 4.03 +/- 3.32 mg/l, Region 4: 5.16 +/- 8.26 mg/l, p
< 0.001). Propensity score analysis revealed higher inter-area
differences in mean cIMT of individuals with coronary artery disease
(CAD) (high vs low air pollution area: 1.56 +/- 0.80 mm; vs. 1.18 +/-
0.54 mm, p < 0.001) while there was no difference in cIMT of the matched
population without CAD (p = 0.52).
Conclusions: An increased carotid atherosclerotic and inflammatory
burden is observed in inhabitants of areas with the highest
concentration of air pollutants