Table 3.
Secondhand maternal smoking, cigarettes consumption amount and duration of tobacco exposure, leukemia cases, and control mothers, children <2 year, Brazil, 1999–2007.
| Smoking | Controls (n = 423), n (%) | ALL (n = 193), n (%) | AML (n = 59), n (%) | ALL |
AML |
||
|---|---|---|---|---|---|---|---|
| OR (95% CI) | OR Adjusteda (95% CI) | OR (95% CI) | OR Adjusteda (95% CI) | ||||
| SECONDHAND SMOKING | |||||||
| Non-smoker mothersb | |||||||
| No | 168 (51.9) | 81 (56.6) | 32 (66.7) | 1.00 | 1.00 | 1.00 | 1.00 |
| Yes | 156 (48.1) | 62 (43.4) | 16 (33.3) | 0.82 (0.56–1.23) | 0.96 (0.63–1.47) | 0.54 (0.28–1.02) | 0.66 (0.34–1.29) |
| FORMER SMOKER MOTHERSc | |||||||
| No | 34 (38.6) | 13 (24.1) | 8 (50.0) | 1.00 | 1.00 | 1.00 | 1.00 |
| Yes | 54 (61.4) | 41 (75.9) | 8 (50.0) | 1.99 (0.93–4.23) | 1.88 (0.81–4.34) | 0.63 (0.22–1.84) | 0.78 (0.22–2.75) |
| SMOKER MOTHERSd | |||||||
| No | 15 (18.3) | 4 (14.7) | 2 (33.3) | 1.00 | 1.00 | 1.00 | 1.00 |
| Yes | 67 (81.7) | 29 (85.3) | 4 (66.7) | 1.29 (0.43–3.91) | 1.62 (0.43–6.14) | 0.45 (0.08–2.68) | 0.67 (0.07–6.10) |
| EXPOSURE AMOUNT DURING PREGNANCYe (CIGARETTES PER) | |||||||
| No use | 304 (71.9) | 137 (71.0) | 48 (81.4) | 1.00 | 1.00 | 1.00 | 1.00 |
| 1–5 | 62 (14.7) | 34 (17.6) | 7 (11.9) | 1.22 (0.77–1.94) | 1.18 (0.70–2.02) | 0.72 (0.31–1.65) | 0.69 (0.27–1.74) |
| 6–19 | 53 (12.5) | 13 (6.7) | 4 (6.8) | 0.54 (0.29–1.03) | 0.61 (0.30–1.24) | 0.48 (0.17–1.38) | 0.37 (0.11–1.28) |
| 20 or more | 4 (0.9) | 9 (4.7) | 0 (0.00) | 4.99 (1.51–16.5) | 5.28 (1.40–19.9) | 0.00 | 0.00 |
| p-trend = 0.75 | |||||||
| EXPOSURE LENGTH (YEARS) | |||||||
| 0–5 | 18 (24.0) | 3 (12.5) | 1 (25.0) | 1.00 | 1.00 | 1.00 | 1.00 |
| 6–9 | 21 (28.0) | 7 (29.2) | 1 (25.0) | 2.00 (0.45–8.89) | 1.43 (0.29–7.06) | 0.86 (0.05–14.71) | 0.51 (0.02–11.15) |
| 10–14 | 16 (21.3) | 6 (25.0) | 1 (25.0) | 2.25 (0.48–10.50) | 1.24 (0.21–7.43) | 1.13 (0.07–19.50) | 1.00 (0.04–21.74) |
| 15+ | 20 (26.7) | 8 (33.3) | 1 (25.0) | 2.40 (0.55–10.46) | 1.74 (0.29–10.32) | 0.90 (0.05–15.47) | 0.22 (0.00–15.52) |
| p-trend = 0.32 | |||||||
aAdjusted OR by maternal age at birth, maternal education, oral contraceptives use during pregnancy, birth weight, and infant skin color.
bNon-smoker mothers living with smokers.
cFormer smoker mothers living with smokers.
dSmoker mothers living with smokers.
eMean daily maternal cigarettes consumption during pregnancy.