Table 1 The characteristics of breast cancer cases and cancer-free controls
Characteristic a | Breast cancer | Control | P-value b | OR (95%CI) | |
|---|---|---|---|---|---|
Age | 47.20 ± 10.41 | 45.88 ± 11.51 | 0.065 | 1.01 (0.99–1.02) | |
Age of menarche | 13.05 ± 1.65 | 13.23 ± 1.56 | 0.116 | 1.07 (0.98–1.16) | |
Age of menopause c | 47.79 ± 5.61 | 48.19 ± 5.21 | 0.545 | 1.01 (0.97–1.06) | |
Age of first gestation | 21.39 ± 5.09 | 22.55 ± 4.53 | 0.001 | 1.05 (1.02–1.08) | |
BMI (Kg/m 2 ) d | 27.66 ± 5.04 | 25.36 ± 4.36 | < 0.001 | 1.11 (1.08–1.14) | |
BMI (Kg/m 2 ) | BMI < 25 | 117 (28.4%) | 260 (50.4%) | Reference |  |
BMI ≥ 25 | 295 (71.6%) | 256 (49.6%) | < 0.001 | 2.56 (1.94–3.37) | |
Menopause status | Pri & pre | 238 (57.9%) | 397 (74.8%) | Reference | Â |
Post | 173 (42.1%) | 134 (25.2%) | < 0.001 | 2.15 (1.63–2.84) | |
History of lactation | Negative | 18 (4.7%) | 20 (4.9%) | Reference | Â |
Positive | 362 (95.3%) | 390 (95.1%) | 0.926 | 1.03 (0.54–1.98) | |
History of abortion | Negative | 236 (64.1%) | 281 (70.3%) | Reference | Â |
Positive | 132 (35.9%) | 119 (29.8%) | 0.071 | 1.32 (0.98–1.79) | |
Physical activity | Negative | 125 (42.4%) | 51 (13.3%) | Reference | Â |
Positive | 170 (57.6%) | 332 (86.7%) | < 0.001 | 4.66 (3.20–6.80) | |