Table 1. Baseline characteristics of study population in highest and lowest quartiles of PM2.5 and NOx.
| Quartile of PM2.5 | Quartile of NOx | |||
|---|---|---|---|---|
| Lowest | Highest | Lowest | Highest | |
| Mean of characteristic (SD) | ||||
|
|
||||
| Age | 38.5 (10.5) | 40.2 (10.9) | 41.1 (11.0) | 39.0 (10.9) |
| Body mass index | 26.9 (6.2) | 28.0 (6.9) | 26.7 (6.1) | 27.8 (6.9) |
| Noise (dB) | 62.7 (4.4) | 62.8 (4.3) | 61.1 (3.7) | 64.6 (4.4) |
| % with characteristic | ||||
|
|
||||
| Highest quartile neighborhood SES score | 25.9 | 17.1 | 48.3 | 11.7 |
| College graduate | 44.2 | 37.9 | 55.8 | 38.0 |
| Income >$100,000 in 2003 | 22.4 | 17.0 | 27.4 | 17.8 |
| Current drinker | 28.7 | 28.1 | 30.3 | 28.0 |
| Current smoker | 12.7 | 15.0 | 10.7 | 15.3 |
| ≥3 hrs/day vigorous exercise | 33.1 | 28.8 | 31.9 | 28.8 |