Table 2.
Odds ratios and 95% confidence intervals for FL risk in relation to personal smoking.
| Exposures | Cases | Reference Category Included Passive Smokers | Reference Category Excluded Passive Smokers | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Related Controls | Unrelated Controls | OR (95% CI) a | p | Related Controls | Unrelated Controls | OR (95% CI) a | p | ||
| Smoking status b | |||||||||
| Never | 369 | 175 | 118 | Ref. | 0.01 | 68 | 35 | Ref. | 0.01 |
| Ever | 340 | 127 | 69 | 1.38 (1.08–1.74) | 127 | 69 | 1.51 (1.09–2.10) | ||
| Smoking status b | |||||||||
| Never | 369 | 175 | 118 | Ref. | 0.03 | 68 | 35 | Ref. | 0.04 |
| Former | 274 | 106 | 56 | 1.36 (1.05–1.77) | 106 | 56 | 1.50 (1.05–2.14) | ||
| Current | 66 | 21 | 13 | 1.43 (0.92–2.20) | 21 | 13 | 1.56 (0.96–2.53) | ||
| Age started smoking b | |||||||||
| Never | 369 | 175 | 118 | Ref. | 0.06 | 68 | 35 | Ref. | 0.08 |
| Tertile 1 (>18) | 97 | 29 | 19 | 1.47 (0.99–2.17) | 29 | 19 | 1.62 (1.02–2.55) | ||
| Tertile 2 (17–18) | 110 | 54 | 25 | 1.20 (0.85–1.70) | 54 | 25 | 1.34 (0.88–2.02) | ||
| Tertile 3 (<17) | 132 | 44 | 25 | 1.47 (1.06–2.05) | 44 | 25 | 1.62 (1.08–2.41) | ||
| Ptrend 0.17 | Ptrend 0.07 | ||||||||
| Years since quitting smoking b | |||||||||
| Never | 369 | 175 | 118 | Ref. | 0.13 | 68 | 35 | Ref. | 0.19 |
| Tertile 1 (≥30) | 95 | 33 | 22 | 1.49 (0.99–2.24) | 33 | 22 | 1.57 (0.97–2.53) | ||
| Tertile 2 (15–29) | 99 | 34 | 21 | 1.37 (0.94–1.99) | 34 | 21 | 1.49 (0.95–2.35) | ||
| Tertile 3 (<15) | 80 | 39 | 13 | 1.24 (0.85–1.81) | 39 | 13 | 1.41 (0.91–2.19) | ||
| Ptrend 0.02 | Ptrend 0.05 | ||||||||
| No. of cigarettes per day b | |||||||||
| Never | 369 | 175 | 118 | Ref. | 0.05 | 68 | 35 | Ref. | 0.04 |
| <10 | 90 | 28 | 17 | 1.54 (1.02–2.32) | 28 | 17 | 1.75 (1.10–2.77) | ||
| 10–19 | 105 | 49 | 24 | 1.19 (0.84–1.68) | 49 | 24 | 1.32 (0.87–1.99) | ||
| ≥20 | 132 | 45 | 25 | 1.44 (1.04–2.01) | 45 | 25 | 1.59 (1.07–2.38) | ||
| Ptrend 0.06 | Ptrend 0.08 | ||||||||
| Duration of cigarette smoking (years) b | |||||||||
| Never | 369 | 175 | 118 | Ref. | 0.04 | 68 | 35 | Ref. | 0.07 |
| Tertile 1 (≤13) | 114 | 45 | 28 | 1.24 (0.87–1.76) | 45 | 28 | 1.35 (0.89–2.06) | ||
| Tertile 2 (14–27) | 106 | 49 | 16 | 1.42 (0.99–2.03) | 49 | 16 | 1.60 (1.05–2.44) | ||
| Tertile 3 (>27) | 119 | 33 | 25 | 1.53 (1.07–2.18) | 33 | 25 | 1.64 (1.07–2.51) | ||
| Ptrend < 0.01 | Ptrend 0.01 | ||||||||
| Lifetime cigarette exposure (pack-years) b | |||||||||
| Never | 369 | 175 | 118 | Ref. | 0.05 | 68 | 35 | Ref. | 0.23 |
| Tertile 1 (<6.8) | 111 | 40 | 21 | 1.43 (0.98–2.06) | 40 | 21 | 1.60 (1.05–2.46) | ||
| Tertile 2 (6.8–19.9) | 102 | 49 | 22 | 1.16 (0.81–1.67) | 49 | 22 | 1.33 (0.87–2.05) | ||
| Tertile 3 (≥20.0) | 113 | 33 | 23 | 1.56 (1.10–2.22) | 33 | 23 | 1.66 (1.09–2.53) | ||
| Ptrend 0.02 | Ptrend 0.06 | ||||||||
a Multivariable model—adjusted for age, sex, ethnicity, state, quantity of alcohol intake 12 months prior to enrolment. ORs are based on related and unrelated controls combined. b Imputations (number of participants with missing values): ever smoking status (1), age started smoking (1), year since quit smoking (1), number of cigarettes per day (22), duration of smoking (2), pack-years (23).