Table 2.

Univariate comparison of biomarkers from smokers with and without cancer

BiomarkeraWithout cancer Geometric mean (95% CI) n =With cancer Geometric mean (95% CI) n =Cancer/no cancer Ratio of Geo means (95% CI)Pb
HPB (pmol/mg DNA)0.046, (0.010–0.210), n = 341.406, (0.622–3.179), n = 3030.82 (5.27–180.37)<0.001
NNAL (pmol/mg creatinine)0.744, (0.373–1.485), n = 271.558, (0.818–2.969), n = 212.09 (0.81–5.38)0.122
NNN (pmol/mg creatinine)0.016, (0.008–0.031), n = 270.012, (0.006–0.023), n = 210.74 (0.29–1.88)0.518
1-HOP (pmol/mg creatinine)0.739, (0.494–1.105), n = 270.829, (0.554–1.240), n = 221.12 (0.64–1.97)0.681
Cotinine (ng/mg creatinine)1,456, (1,033–2,051), n = 271,689, (1,074–2,657), n = 201.16 (0.68–1.99)0.583
3OH cotinine (ng/mL)3,575, (2,322–5,503), n = 304,233, (2,834–6,321), n = 251.18 (0.66–2.12)0.564
Biomarker ratioMean (SD) (95% CI) n =Mean (SD) (95% CI) n =Difference in means cancer-no cancer (SD; 95% CI)Pc
3OH cotinine/total cotinine ratio2.96 (1.77), (2.29–3.64), n = 293.83 (1.89) (3.02–4.65) n = 230.87 (1.82; −0.15–1.89)0.094
  • NOTE: P values < 0.05 are considered significant.

  • aBiomarkers were analyzed in the natural logarithmic scale.

  • bThe P value is based on the two-sample t test for the difference of means in the log scale.

  • cThe P value is based on the two-sample t test for the difference of mean ratios.