Table 3.
Mean Biomarkers Among Menthol and Nonmenthol Daily Smokers, Age 18–35
| Biomarkera | Total (n = 179) | Menthol (n = 122) | Nonmenthol (n = 57) | Total (n = 179) | Menthol (n = 122) | Nonmenthol (n = 57) | ||
|---|---|---|---|---|---|---|---|---|
| Mean (SE) | Mean (SE) | Mean (SE) | P | Mean (SE) | Mean (SE) | Mean (SE) | P | |
| Model 1-unadjusted | Model 2b | |||||||
| Nicotine (ng/ml) | 64.5 (3.4) | 67.8 (3.4) | 57.0 (4.4) | .43 | 57.5 (3.4) | 64.6 (3.4) | 51.2(4.4) | .35 |
| Cotinine (ng/ml) | 130.2 (7.7) | 134.5 (9.2) | 120.5 (14.3) | .46 | 116.4 (7.7) | 124.9(9.2) | 108.5 (14.3) | .40 |
| Cotinine/cpd ratio | 11.2 (0.95) | 11.3 (1.2) | 11.0 (1.4) | .86 | 11.0 (0.95) | 12.0 (1.2) | 10.1 (1.4) | .29 |
| 3HC | 28.8 (2.4) | 26.6 (2.8) | 34.9 (4.4) | .05 | 28.5 (2.4) | 26.4 (2.8) | 30.7 (4.4) | .35 |
| NMRc | 0.20 (0.01) | 0.18 (0.01) | 0.26 (0.3) | .001*** | 0.21 (0.01) | 0.19 (0.01) | 0.24 (0.03) | .04* |
| CO (ppm) | 10.0 (0.53) | 10.9 (0.70) | 9.3(0.73) | .10 | 10.0 (0.53) | 10.5 (0.70) | 9.5 (0.73) | .38 |
| Model 3d | ||||||||
| Nicotine (ng/ml) | 54.7 (45.1) | 62.2 (62.3) | 48.2(30.5) | .29 | — | — | — | — |
| Cotinine (ng/ml) | 111.9 (7.7) | 120.8(9.2) | 103.7 (14.3) | .33 | — | — | — | — |
| Cotinine/cpd ratio | 11.3 (0.95) | 12.3 (1.2) | 10.4 (1.4) | .30 | — | — | — | — |
| 3HC | 27.2 (2.4) | 25.0 (2.8) | 29.7(4.4) | .23 | — | — | — | — |
| NMRc | 0.21 (0.01) | 0.19 (0.01) | 0.24 (0.03) | .03* | — | — | — | — |
| CO (ppm) | 9.8(7.1) | 10.3 (7.7) | 9.4 (5.5) | .37 | — | — | — | — |
3HC = trans 3′ hydroxycotinine; BMI = body mass index; CO = carbon monoxide; cpd = cigarettes per day; ppm = parts per million; SE = standard error.
aAll biomarker data are geometric means.
bGeometric means adjusted for gender, race, and BMI.
cNicotine metabolite ratio (NMR) = ratio of 3 hydroxycotinine/cotinine.
dGeometric means adjusted for gender race, BMI, and cpd.
*P < .05; ***P < .001.