Table 2.
Biomarkers in quartile (cut-off values)* | Cases | Controls | OR† (95% CI) |
---|---|---|---|
Total nicotine (nmol/mg creatinine) | |||
1st (<3.85) | 30 | 86 | 1.00 |
2nd (3.85-9.56) | 77 | 91 | 2.10 (1.22-3.61) |
3rd (9.57-18.47) | 91 | 90 | 2.35 (1.38-4.00) |
4th (>18.47) | 127 | 89 | 3.03 (1.80-5.10) |
P for trend | <0.001 | ||
Total cotinine (nmol/mg creatinine) | |||
1st (<3.89) | 20 | 80 | 1.00 |
2nd (3.89-9.07) | 49 | 93 | 2.00 (1.08-3.71) |
3rd (9.08-15.81) | 110 | 94 | 3.35 (1.86-6.04) |
4th (>15.81) | 146 | 89 | 4.70 (2.61-8.46) |
P for trend | <0.001 | ||
Total 3HC (nmol/mg creatinine) | |||
1st (<4.17) | 19 | 79 | 1.00 |
2nd (4.17-10.79) | 62 | 89 | 2.31 (1.25-4.28) |
3rd (10.80-20.13) | 89 | 89 | 3.02 (1.65-5.51) |
4th (>20.13) | 155 | 99 | 4.26 (2.37-7.68) |
P for trend | <0.001 | ||
TNE (nmol/mg creatinine)‡ | |||
1st (<15.64) | 19 | 78 | 1.00 |
2nd (15.64-33.27) | 51 | 93 | 1.91 (1.02-3.58) |
3rd (33.28-54.28) | 96 | 90 | 3.26 (1.79-5.93) |
4th (>54.28) | 159 | 95 | 4.71 (2.61-8.52) |
P for trend | <0.001 | ||
Total NNAL (pmol/mg creatinine)§ | |||
1st (<0.09) | 33 | 86 | 1.00 |
2nd(0.10-0.15) | 69 | 88 | 1.87 (1.10-3.18) |
3rd (0.16-0.25) | 96 | 92 | 2.09 (1.24-3.51) |
4th (>0.25) | 119 | 82 | 3.15 (1.86-5.33) |
P for trend | <0.001 |
Abbreviations: NNAL, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol; 3HC, trans-3′-hydroxycotinine; TNE, total nicotine equivalents; OR, odds ratio; CI, confidence interval.
Adjusted for number of cigarettes per day, number of years of smoking, and matching factors.
The sum of total nicotine, total cotinine and total 3HC.
Sixteen subjects (8 cases and 8 controls) were excluded from this analysis due to missing total NNAL.