Table 4.

Associations of air pollutants (2008 Annual average) and distance to roadway with pulmonary vascular volumes on CT^a

Exposure	Model N	Difference in TBV, mL (95% CI)	P	Difference in BV5, mL (95% CI)	P	Difference in BV10, mL (95% CI)	P
PM2.5	2017	−0.48 (−1.42 to 0.47)	0.32	−0.26 (−0.68 to 0.16)	0.22	−0.30 (−0.83 to 0.24)	0.28
Elemental carbon	2018	0.24 (−0.29 to 0.78)	0.37	0.18 (−0.05 to 0.42)	0.13	0.19 (−0.11 to 0.50)	0.22
Ozone	2240	−0.55 (−1.17 to 0.06)	0.08	−0.34 (−0.61 to −0.06)	0.02	−0.44 (−0.80 to −0.09)	0.01
Distance to roadwayb	1985	0.90 (−0.21 to 2.01)	0.11	0.40 (−0.10 to 0.89)	0.12	0.45 (−0.18 to 1.08)	0.16
Exposure	Model N	Difference in TBV, mL (95% CI)	P	Difference in BV5, mL (95% CI)	P
PM2.5	2017	−0.08 (−0.21 to 0.06)	0.27	−0.03 (−0.16 to 0.10)	0.62
Elemental carbon	2018	0.06 (−0.01 to 0.14)	0.11	0.05 (−0.02 to 0.12)	0.18
Ozone	2240	−0.05 (−0.14 to 0.04)	0.27	−0.06 (−0.15 to 0.03)	0.17
Distance to roadwayb	1985	0.03 (−0.14 to 0.19)	0.76	−0.03 (−0.19 to 0.12)	0.66

^aAll models adjusted for age at time of CT, sex, height, weight, smoking status, total pack-years of cigarette exposure, second-hand tobacco exposure during adulthood, personal educational attainment, occupation category, median value of owner-occupied housing, study cohort, date of CT and sine and cosine day of the year terms (to account for seasonality and time), any history of cardiovascular disease, and FEV₁. Distance to roadway analysis excludes 292 participants (12.0%) who lived ≥1,000 m from a major roadway. Results expressed per IQR of exposure.

^bDistance to roadway is defined as the negative natural log of distance to roadway (with higher values therefore indicating greater traffic-related pollution exposure).

CI indicates confidence interval; CT, computed tomography; IQR, interquartile range.