Table 1.
Baseline smoking characteristics and biomarkers in African Americans and Whites by NMR quartile.
| Whites | African Americans | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||||
| Variable (N) | Q1 (194) |
Q2 (277) |
Q3 (306) |
Q4 (325) |
Total (1102) |
Q1 (230) |
Q2 (148) |
Q3 (115) |
Q4 (98) |
Total (598) |
t-statistic† (p-value) |
| Age | 44.6 ± 12.2 | 44.3 ± 11.6 | 46.1 ± 10.7 | 46.7 ± 11.2 | 45.6 ± 11.4 | 45.6 ± 10.5 | 44.8 ± 11.1 | 46.9 ± 10.1 | 49.7 ± 8.8 | 46.3 ± 10.4 | 1.33 (1.81) |
|
| |||||||||||
| % Female | 34.5% | 35.7% | 48.7% | 48.6% | 42.9% | 43.9% | 49.3% | 56.5% | 55.1% | 49.6% | 7.32 (0.007) |
|
| |||||||||||
| ≥High school education | 94.8% | 96.4% | 94.4% | 93.2% | 94.6% | 86.1% | 87.2% | 90.4% | 93.9% | 88.5% | 22.05† (<0.001) |
|
| |||||||||||
| Income > US $50, 000 | 50.0% | 52.0% | 52.5% | 45.5% | 49.9% | 17.4% | 18.8 % | 13.9 % | 14.4 % | 16.6% | 179.02† (<0.001) |
|
| |||||||||||
| CPD | 19.0 ± 6.0 | 19.7 ± 7.3 | 20.6 ± 7.3 | 20.2 ± 7.4 | 20.0 ± 7.1 | 15.9 ± 6.0 | 16.0 ± 6.1 | 16.4 ± 5.9 | 16.4 ± 6.6 | 16.1 ± 6.1 | −11.78 (<0.001) |
|
| |||||||||||
| Expired CO (ppm) | 24.0 ± 10.0 | 23.4 ± 9.7 | 24.9 ± 10.2 | 24.1 ± 10.5 | 24.1 ± 10.1 | 21.7 ± 9.9 | 22.2 ± 10.6 | 22.2 ± 11.3 | 22.3 ± 10.0 | 22.0 ± 10.4 | −3.95 (<0.001) |
|
| |||||||||||
| Menthol smoker* | 18.8% | 25.2% | 23.5% | 24.0% | 22.9% | 87.6% | 86.0% | 79.7% | 75.5% | 84.4% | 429.80† (<0.001) |
|
| |||||||||||
| FTCD score | 5.2 ± 2.1 | 5.3 ± 1.9 | 5.5 ± 1.9 | 5.3 ± 2.0 | 5.3 ± 2.0 | 5.3 ± 1.9 | 5.3 ± 1.6 | 5.2 ± 2.1 | 4.8 ± 2.0 | 5.2 ± 1.9 | −1.21 (0.227) |
|
| |||||||||||
| TTFC | |||||||||||
| Within 5 min | 32.0% | 30.7% | 32.7% | 32.3% | 31.9 % | 42.6% | 51.4% | 53.9% | 41.8% | 46.9 % | 38.21 (<0.001) |
| 6–30 min | 45.4% | 52.0% | 50.0% | 49.8% | 49.6 % | 41.7% | 37.8% | 30.4% | 36.7% | 37.7 % | |
| 31–60 min | 16.0% | 12.3% | 13.1% | 10.2% | 12.5 % | 10.9% | 7.4% | 8.7% | 11.2% | 9.6 % | |
| After 60 min | 6.7% | 5.1% | 4.2% | 7.7% | 5.9 % | 4.8% | 3.4% | 7.0% | 10.2% | 5.8 % | |
|
| |||||||||||
| NMR | .17 ± .05 | .30 ± .03 | .41 ± .04 | .66 ± .18 | 0.41 ± 0.20 | .16 ± .05 | .29 ± .03 | .41 ± .04 | .69 ± .22 | 0.33 ± 0.21 | −8.19 (<0.001) |
|
| |||||||||||
| Blood cotinine (ng/mL) | 239.8 ± 101.6 | 252.4 ± 113.0 | 246.5 ± 105.3 | 214.1 ± 99.1 | 237.2 ± 105.9 | 300.0 ± 148.1 | 269.4 ± 121.3 | 253.4 ± 111.0 | 206.2 ± 103.5 | 267.7 ± 131.9 | 5.16 (<0.001) |
|
| |||||||||||
| Blood 3HC (ng/mL) | 42.0 ± 21.1 | 75.9 ± 35.5 | 101.4 ± 45.1 | 138.2 ± 70.9 | 95.4 ± 59.9 | 49.2 ± 30.7 | 78.1 ± 34.4 | 102.3 ± 43.3 | 134.9 ± 69.1 | 81.0 ± 52.7 | −5.13 (<0.001) |
|
| |||||||||||
| Blood cotinine + 3HC (nmols/mL) | 1.6 ± 0.7 | 1.8 ± 0.8 | 1.9 ± 0.8 | 1.9 ± 0.9 | 1.8 ± 0.8 | 2.0 ± 1.0 | 1.9 ± 0.9 | 2.0 ± 0.9 | 1.9 ± 0.9 | 1.9 ± 0.9 | 2.27 (0.02) |
|
| |||||||||||
| Blood cotinine/ CPD | 13.2 ± 5.5 | 13.7 ± 6.6 | 12.7 ± 5.6 | 11.5 ± 6.2 | 12.7 ± 6.1 | 20.5 ±11.1 | 19.1 ± 12.2 | 17.0 ± 8.9 | 13.7± 7.6 | 18.3 ± 10.7 | 13.77 (<0.001) |
|
| |||||||||||
| Blood [Cotinine + 3HC]/ CPD | .09 ± .04 | .10 ± .05 | .10 ± .04 | .10 ± .06 | 0.10 ± 0.05 | .13 ± .07 | .14 ± .09 | .13 ± .07 | .12 ± .07 | 0.13 ± 0.07 | 11.40 (<0.001) |
Note. T-tests were calculated comparing total Caucasian vs African American smokers.
†
= χ2 used for categorical variables. Means are presented ± standard deviation.
*
Menthol smoking was not assessed in all participants and prevalence of use is based on 474 African Americans and 704 Whites. Q = Nicotine metabolite ratio (NMR) quartile based on the full sample; CPD= Cigarettes per day; CO= Carbon Monoxide in parts per million; FTCD = Fagerström Test for Cigarette Dependence; TTFC = Time to first cigarette after waking; NMR= Nicotine Metabolite Ratio; 3HC= trans 3′ hydroxyl cotinine.