Table 4.
Differences in cancer-related markers between PAH-exposed groups and control group (reference group); (A) chimney sweeps versus controls, and (B) creosote workers versus controls, explored by general linear models; Model 1, adjusted for age and smoking: Model 2, adjusted for age among non-smokers and Model 3, fully adjusted
| Model 1a | Model 2b | Model 3c | ||||
|---|---|---|---|---|---|---|
| P | B1 (95% CI) | P | B1 (95% CI) | P | B1 (95% CI) | |
| (A) Chimney sweeps versus controlsd | ||||||
| Telomere length | 0.698 | −0.005 (−0.028, 0.019) | 0.986 | 0.0003 (−0.034, 0.035) | 0.517 | −0.01 (−0.031, 0.016) |
| MtDNA copy number | 0.102 | −0.03 (−0.074, 0.007) | 0.126 | −0.04 (−0.089, 0.011) | 0.131 | −0.03 (−0.072, 0.009) |
| F2RL3_CpG1 | 0.110 | −0.98 (−2.18, 0.22) | 0.055 | −1.13 (−2.29, 0.02) | 0.125 | −0.96 (−2.19, 0.27) |
| F2RL3_CpG2 (cg03636183) | 0.962 | 0.03 (−1.02, 1.07) | 0.296 | −0.49 (−1.43, 0.44) | 0.952 | −0.03 (−1.10, 1.04) |
| F2RL3_average | 0.348 | −0.48 (−1.47, 0.52) | 0.042 | −0.81 (−1.60, −0.03) | 0.338 | −0.50 (−1.52, 0.52) |
| AHRR_CpG1 | 0.145 | −1.55 (−3.63, 0.54) | 0.063 | −1.87 (−3.83, 0.10) | 0.169 | −1.50 (−3.63, 0.64) |
| AHRR_CpG2 | 0.007 | −2.55 (−4.42, −0.69) | 0.007 | −2.30 (−3.96, −0.65) | 0.011 | −2.46 (−4.37, −0.56) |
| AHRR_CpG3 (cg05575921) | 0.057 | −2.04 (−4.14, 0.06) | 0.104 | −1.64 (−3.62, 0.34) | 0.078 | −1.93 (−4.08, 0.22) |
| AHRR_average | 0.035 | −2.05 (−3.95, −0.15) | 0.019 | −1.94 (−3.55, −0.32) | 0.048 | −1.96 (−3.91, −0.02) |
| (B) Creosote workers versus controlse | ||||||
| Telomere length | 0.893 | −0.004 (−0.055, 0.048) | — | — | — | — |
| MtDNA copy number | 0.532 | 0.030 (−0.065, 0.125) | — | — | — | — |
| F2RL3_CpG1 | <0.001 | −4.75 (−7.35, −2.15) | — | — | — | — |
| F2RL3_CpG2 (cg03636183) | <0.001 | −4.93 (−7.21, −2.64) | — | — | — | — |
| F2RL3_average | <0.001 | −4.84 (−7.00, −2.67) | — | — | — | — |
| AHRR_CpG1 | 0.075 | −4.25 (−8.95, 0.44) | — | — | — | — |
| AHRR_CpG2 | 0.501 | −1.46 (−5.72, 2.81) | — | — | — | — |
| AHRR_CpG3 (cg05575921) | <0.001 | −9.23 (−13.63, −4.94) | — | — | — | — |
| AHRR_average | 0.020 | −5.00 (−9.19, −0.81) | — | — | — | — |
Effect estimates are presented as B values and 95% confidence interval (95% CI).
a(cancer-related marker) = intercept + B1 × exposure group (2 categories) + B2 × age (continuous) + B3 × smoking status (3 categories) + e (residual error).
b(cancer-related marker) = intercept + B1 × exposure group (2 categories) + B2 × age (continuous) + e (residual error). Current and party-/ex-smokers were excluded from this analysis.
c(cancer-related marker) = intercept + B1 × exposure group (2 categories) + B2 × age (continuous) + B3 × smoking status (3 categories) + B4 × use of snus (2 categories) + B5 × passive smoking (2 categories) + B6 × exposure to PAH from hobby (2 categories) + e (residual error).
dNumber of cases included ranged between n = 143–145 for chimney sweeps and n = 147–148 for controls in Model 1; n = 71–73 for chimney sweeps and n = 82–83 for controls in Model 2 and n = 142–144 for chimney sweeps and n = 147–148 for controls in Model 3.
eNumber of cases included ranged between n = 17–18 for creosote-exposed workers and n = 147–148 for controls. Models 2 and 3 were not computed for this comparison due to small sample size of the group of creosote-exposed workers (only nine participants were non-smokers).