Table 1
FTND score, nicotine, cotinine, 3HC concentration (ng/mg creatinine), and NMR according to general characteristics of the study population.
| N (%) | FTND mean (SD) | P value | Nicotine (ng/mg) mean (SD) | P value | Cotinine (ng/mg) mean (SD) | P value | 3HC (ng/mg) mean (SD) | P value | NMR mean (SD) | P value | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Total | 289 (100) | 3.2 (2.4) | 1282.7 (1344.4) | 1549.4 (1420.7) | 3859.1 (4174.3) | 2.8 (1.8) | ||||||
| Age | 0.002* | 0.007* | 0.385 | 0.245 | 0.736 | |||||||
| 18–34 | 86 (29.8) | 2.4 (2.1) | 913.9 (993.8) | 1382.9 (1230.9) | 3379.4 (3449.1) | 2.7 (1.8) | ||||||
| 35–49 | 106 (36.7) | 3.3 (2.4) | 1374.0 (1544.5) | 1573.7 (1673.9) | 3754.6 (3544.6) | 2.9 (2.1) | ||||||
| ≥ 50 | 97 (33.6) | 3.6 (2.5) | 1510.1 (1324.9) | 1670.5 (1268.5) | 4398.6 (5242.7) | 2.7 (1.6) | ||||||
| BMI | 0.988 | 0.048* | 0.040* | 0.209 | 0.214 | |||||||
| <18.5 | 13 (4.5) | 3.2 (2.0) | 1394.4 (1665.7) | 1669.1 (1191.3) | 3779.0 (2829.8) | 3.1 (2.4) | ||||||
| 18.5–23.9 | 144 (49.8) | 3.2 (2.3) | 1308.2 (1314.5) | 1623.8 (1398.2) | 4237.3 (4913.5) | 2.7 (1.8) | ||||||
| 24.00–27.9 | 99 (34.3) | 3.1 (2.5) | 1430.3 (1482.7) | 1648.1 (1583.1) | 3759.6 (3528.3) | 2.6 (1.6) | ||||||
| ≥28 | 33 (11.4) | 3.2 (2.4) | 685.6 (573.4) | 881.5 (838.2) | 2538.7 (2309.5) | 3.3 (2.5) | ||||||
| Smoking years | 0.000* | 0.005* | 0.059 | 0.123 | 0.579 | |||||||
| ≤15 | 91 (31.5) | 2.2 (2.1) | 908.8 (1244.2) | 1270.1 (1273.3) | 3118.1 (3651.7) | 2.6 (1.7) | ||||||
| 16–30 | 113 (39.1) | 3.3 (2.3) | 1469.2 (1340.6) | 1740.9 (1614.3) | 4195.9 (3605.5) | 2.8 (1.8) | ||||||
| >31 | 85 (29.4) | 4.1 (2.5) | 1435.1 (1385.6) | 1593.7 (1254.1) | 4204.6 (5220.4) | 2.9 (2.1) | ||||||
| CPD | 0.000* | 0.002* | 0.001* | 0.000* | 0.103 | |||||||
| ≤10 | 95 (32.9) | 1.2 (1.6) | 890.6 (904.9) | 1090.5 (1069.6) | 2435.0 (2741.7) | 2.6 (1.9) | ||||||
| 11–20 | 160 (55.4) | 3.9 (2.0) | 1490.6 (1470.4) | 1781.7 (1541.9) | 4394.7 (3836.0) | 2.7 (1.5) | ||||||
| ≥21 | 34 (11.8) | 5.3 (2.3) | 1400.2 (1535.5) | 1738.2 (1413.2) | 5317.6 (7094.9) | 3.4 (2.7) |
Table 2
Spearman correlation coefficients among measured biomarkers and variables obtained from questionnaires.
| FTND | Nicotine | Cotinine | 3HC | CPD | Age | Smoking years | NMR | |
|---|---|---|---|---|---|---|---|---|
| FTND | 1.000 | 0.301** | 0.371** | 0.365** | 0.615** | 0.238** | 0.317** | 0.057 |
| Nicotine | 0.301** | 1.000 | 0.702** | 0.482** | 0.163** | 0.245** | 0.264** | −0.204** |
| Cotinine | 0.371** | 0.702** | 1.000 | 0.762** | 0.251** | 0.155** | 0.197** | −0.153** |
| 3HC | 0.365** | 0.482** | 0.762** | 1.000 | 0.293** | 0.131* | 0.186** | 0.431** |
| CPD | 0.615** | 0.163** | 0.251** | 0.293** | 1.000 | 0.228** | 0.278** | 0.075 |
| Age | 0.238** | 0.245** | 0.155** | 0.131* | 0.228** | 1.000 | 0.897** | 0.014 |
| Smoking years | 0.317** | 0.264** | 0.197** | 0.186** | 0.278** | 0.897** | 1.000 | 0.037 |
| NMR | 0.057 | −0.204** | −0.153** | 0.431** | 0.075 | 0.014 | 0.037 | 1.000 |
Table 3
Nicotine, cotinine, 3HC concentration (ng/mg creatinine) and NMR according to FTND.
| FTND items: | N (%) | Nicotine | Cotinine | 3HC | NMR | ||||
|---|---|---|---|---|---|---|---|---|---|
| Mean (SD) | P | Mean (SD) | P | Mean (SD) | P | Mean (SD) | P | ||
| (1) Time to first cigarette | 0.000* | 0.000* | 0.000* | 0.763 | |||||
| After 60 min (0 points) | 107 (37.0) | 850.2 (875.0) | 1029.4 (935.2) | 2457.2 (2579.9) | 2.7 (1.8) | ||||
| 31–60min (1 point) | 61 (21.1) | 1298.2 (1490.4) | 1476.6 (1137.5) | 3771.0(3390.6) | 2.9 (1.8) | ||||
| 6–30min (2 points) | 53 (18.3) | 1487.7 (1299.1) | 2002.0 (1754.2) | 5329.7(6596.0) | 2.6 (1.7) | ||||
| Within 5 min (3 points) | 68 (23.5) | 1789.8 (1632.7) | 2078.0 (1691.6) | 4997.8 (3760.0) | 2.9 (2.0) | ||||
| (2) Difficult to refrain from smoking | 0.08 | 0.297 | 0.800 | 0.721 | |||||
| No (0 points) | 223 (77.2) | 1207.5 (1228.1) | 1501.9 (1284.1) | 3893.1 (4374.4) | 2.8 (1.7) | ||||
| Yes (1 point) | 66 (22.8) | 1536.9 (1665.0) | 1710.0 (1810.1) | 3744.2 (3440.0) | 2.7 (2.2) | ||||
| (3) Hating most to give up smoking | 0.002* | 0.000* | 0.010* | 0.729 | |||||
| All others (0 points) | 200 (69.2) | 1121.4 (1303.9) | 1316.3 (1225.0) | 3440.0 (4370.7) | 2.8 (1.9) | ||||
| The first one in the morning (1 point) | 89 (30.8) | 1645.3 (1370.6) | 2073.2 (1676.8) | 4800.9 (3540.0) | 2.7 (1.7) | ||||
| (4) Cigarettes per day | 0.005* | 0.002* | 0.000* | 0.034 | |||||
| 10 or fewer (0 points) | 97 (33.6) | 893.3 (902.0) | 1098.0 (1065.4) | 2415.6 (2721.3) | 2.6 (1.9) | ||||
| 11–20 (1 point) | 153 (52.9) | 1508.3 (1490.3) | 1800.5 (1577.4) | 4443.1 (3911.3) | 2.7 (1.6) | ||||
| 21–30 (2 points) | 28 (9.7) | 1403.1 (1655.7) | 1690.8 (1249.3) | 5319.7 (7599.2) | 2.9 (1.7) | ||||
| 31 or more (3 points) | 11 (3.8) | 1273.0 (889.6) | 1677.3 (1478.8) | 4747.4 (3164.9) | 4.3 (3.7) | ||||
| (5) Smoking more in the first hours | 0.033* | 0.038* | 0.131 | 0.158 | |||||
| No (0 points) | 244 (84.4) | 1210.5 (1311.6) | 1475.1 (1362.5) | 3700.0 (4278.5) | 2.7 (1.6) | ||||
| Yes (1 point) | 45 (15.6) | 1674.2 (1464.0) | 1952.1 (1662.2) | 4722.8 (3471.3) | 3.1 (2.7) | ||||
| (6) Smoking when ill | 0.006* | 0.005* | 0.000* | 0.353 | |||||
| No (0 points) | 189 (65.4) | 1125.7 (1188.8) | 1377.9 (1302.0) | 3176.5 (2832.8) | 2.7 (1.8) | ||||
| Yes (1 point) | 100 (34.6) | 1579.6 (1561.5) | 1873.6 (1578.2) | 5149.2 (5734.1) | 2.8 (2.0) | ||||
Figure 1
Comparison of cotinine, nicotine and 3HC levels in human urine by the FTND scores. Nicotine dependence groups (low, FTND score = 0 – 4; high, FTND score = 5 – 10); FTND: Fagerström Test for Nicotine Dependence; 3HC: 3′-Hydroxycotinine; * Significant at P < 0.05.
Table 4
Relationship between the FTND scores and cotinine, nicotine and 3HC levels in human urine.
| Cotinine | low | 1314.0 ± 1115.1 ng/mg creatinine |
| high | 1813.61 ± 1262.2 ng/mg creatinine | |
| 3HC | low | 3086.9 ± 2899.6 ng/mg creatinine |
| high | 4930.3 ± 4033.8 ng/mg creatinine | |
| Nicotine | low | 1062.9 ± 1072.6 ng/mg creatinine |
| high | 1670.2 ± 1545.9 ng/mg creatinine |