Table 6.

Association between smoking and breast cancer by residence

By country (region)	Univariate analysis OR (95% CI) P	Multivariate analysis* OR (95% CI) P
USA (all) (917 pairs)	1.12 (0.92–1.37) 0.25	1.11 (0.91–1.36) 0.30
BRCA1 (633 pairs)	1.28 (1.02–1.61) 0.04	1.25 (0.98–1.58) 0.07
BRCA2 (284 pairs)	0.78 (0.54–1.15) 0.21	0.79 (0.54–1.16) 0.23
Other Canada (all) (511 pairs)	1.02 (0.80–1.31) 0.85	1.03 (0.80–1.32) 0.83
BRCA1 (313 pairs)	1.06 (0.78–1.450 0.70	1.06 (0.78–1.45) 0.70
BRCA2 (198 pairs)	0.96 (0.63–1.45) 0.83	0.99 (0.65–1.50) 0.96
Quebec (all) (101 pairs)	0.55 (0.34–0.89) 0.02	0.51 (0.31–0.83) 0.008
BRCA1 (93 pairs)	0.69 (0.38–1.26) 0.23	0.67 (0.35–1.27) 0.21
BRCA2 (70 pairs)	0.38 (0.17–0.86) 0.02	0.33 (0.14–0.78) 0.01
Israel (all) (101 pairs)	0.58 (0.28–1.22) 0.15	0.65 (0.30–1.40) 0.28
BRCA1 (77 pairs)	0.50 (0.21–1.17) 0.11	0.57 (0.24–1.37) 0.21
BRCA2 (24 pairs)	1.00 (0.20–4.96) 1.00	1.47 (0.25–8.76) 0.68
Poland (all) (565 pairs)	1.01 (0.80–1.27) 0.95	1.02 (0.81–1.28) 0.89
BRCA1 (564 pairs)	1.01 (0.80–1.27) 0.95	1.02 (0.81–11.28) 0.89
BRCA2 (1 pair)	NA	NA
Other Europe (all) (281 pairs)	1.40 (0.94–2.06) 0.10	1.38 (0.93–2.04) 0.11
BRCA1 (240 pairs)	1.42 (0.93–2.17) 0.11	1.41 (0.92–2.16) 0.12
BRCA2 (41 pairs)	1.29 (0.48–3.45) 0.62	1.28 (0.45–3.66) 0.64

^*The multivariate odds ratios are adjusted for oral contraceptive use (yes/no) and parity (0, 1, 2, 3, 4, … 9)