Table 3.
Association of PM10 and PM1 exposure with the levels of methylation at three CpG positions in the promoter of hTERT at baseline and postexposure.
| hTERT methylation | Exposure | Unadjusted
|
Adjusteda |
||
|---|---|---|---|---|---|
| βb (95% CI) | p-Value | βb (95% CI) | p-Value | ||
| CpG position 1
| |||||
| Baseline (n = 59c) | PM10 | −0.02 (−0.39 to 0.36) | 0.93 | 0.08 (−0.34 to 0.50) | 0.71 |
| PM1 | −0.08 (−0.58 to 0.42) | 0.76 | −0.02 (−0.6 to 0.56) | 0.95 | |
| Postexposure (n = 59c) | PM10 | −0.13 (−0.55 to 0.28) | 0.53 | −0.15 (−0.62 to 0.32) | 0.52 |
| PM1 | −0.13 (−0.68 to 0.43) | 0.65 | −0.13 (−0.76 to 0.50) | 0.69 | |
| Differenced (n = 59c) | PM10 | −0.11 (−0.65 to 0.42) | 0.67 | −0.24 (−0.84 to 0.36) | 0.43 |
| PM1 | −0.05 (−0.77 to 0.67) | 0.89 | −0.03 (−0.83 to 0.77) | 0.95 | |
| CpG position 2
| |||||
| Baseline (n = 59c) | PM10 | 0.15 (−0.89 to 1.20) | 0.77 | 0.05 (−1.18 to 1.27) | 0.94 |
| PM1 | −0.15 (−1.55 to 1.26) | 0.83 | −0.32 (−2.00 to 1.36) | 0.71 | |
| Postexposure (n = 59c) | PM10 | −0.26 (−1.41 to 0.89) | 0.65 | −0.43 (−1.75 to 0.89) | 0.52 |
| PM1 | −0.35 (−1.89 to 1.19) | 0.65 | −0.81 (−2.58 to 0.97) | 0.36 | |
| Differenced (n = 59c) | PM10 | −0.41 (−1.83 to 1.00) | 0.56 | −0.57 (−2.27 to 1.12) | 0.50 |
| PM1 | −0.20 (−2.11 to 1.70) | 0.83 | −0.33 (−2.59 to 1.93) | 0.77 | |
| CpG position 3
| |||||
| Baseline (n = 59c) | PM10 | −0.20 (−0.91 to 0.50) | 0.56 | −0.21 (−1.00 to 0.59) | 0.61 |
| PM1 | −0.64 (−1.57 to 0.29) | 0.18 | −0.68 (−1.76 to 0.40) | 0.21 | |
| Postexposure (n = 59c) | PM10 | −0.73 (−1.24 to −0.22) | 0.006 | −0.70 (−1.26 to −0.13) | 0.017 |
| PM1 | −1.00 (−1.69 to −0.32) | 0.005 | −1.00 (−1.76 to −0.25) | 0.010 | |
| Differenced (n = 59c) | PM10 | −0.53 (−1.19 to 0.13) | 0.12 | −0.55 (−1.30 to 0.20) | 0.15 |
| PM1 | −0.37 (−1.27 to 0.54) | 0.42 | −0.21 (−1.22 to 0.81) | 0.69 | |
a
Regression coefficients, 95% confidence intervals (CIs), and p-values estimated from multivariable regression models adjusted for age, BMI, pack-years, and percent lymphocytes.
b
β for an increment equal to the difference between the 90th and 10th percentiles of exposure (285.96 μg/m3 for PM10 and 11.05 μg/m3 for PM1).
c
Values were missing for some subjects because of assay failure; statistical analysis was restricted to subjects with nonmissing values in both the baseline and the postexposure samples.
d
Postexposure – baseline.