Variable | Premenopausal women, N = 449a | Postmenopausal women, N = 579a | P-het†| ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Control N = 217 | Case N = 233 | Multivariable model* | Control N = 297 | Case N = 282 | Multivariable model* | ||||||
Na | %a | Na | %a | OR (95% CI)* | Na | %a | Na | %a | OR (95% CI)* | ||
Age at first full-term birth/years | |||||||||||
 Nulliparous/≥ 30 | 57 | 26.3 | 83 | 35.7 | 1.00 (ref) | 50 | 17.0 | 56 | 20.0 | 1.00 (ref) | 0.35 |
 < 30 | 160 | 73.7 | 150 | 64.3 | 0.59 (0.38, 0.90) | 247 | 83.0 | 226 | 80.0 | 0.81 (0.47, 1.38) |  |
 P-value |  |  |  |  | 0.015 |  |  |  |  | 0.43 |  |
Family history of breast cancer | |||||||||||
 No | 190 | 87.5 | 186 | 80.0 | 1.00 (ref) | 244 | 82.2 | 225 | 79.9 | 1.00 (ref) | 0.28 |
 Yes | 27 | 12.5 | 47 | 20.0 | 1.75 (1.00, 3.07) | 53 | 17.8 | 57 | 20.1 | 1.18 (0.76, 1.83) |  |
 P-value |  |  |  |  | 0.052 |  |  |  |  | 0.46 |  |
History of bilateral oophorectomy | |||||||||||
 No | – | – | – | – | – | 212 | 71.3 | 221 | 78.3 | 1.00 (ref) | – |
 Yes | – | – | – | – | – | 85 | 28.7 | 61 | 21.7 | 0.66 (0.44, 0.99) |  |
 P-value |  |  |  |  | – |  |  |  |  | 0.044 |  |
BBD histology | |||||||||||
 Normal/non-proliferative | 178 | 81.9 | 157 | 67.5 | 1.00 (ref) | 206 | 69.5 | 167 | 59.4 | 1.00 (ref) | 0.47 |
 Proliferative without atypia | 37 | 17.2 | 67 | 28.7 | 2.06 (1.27, 3.33) | 87 | 29.2 | 97 | 34.2 | 1.41 (0.97, 2.03) |  |
 Proliferative with atypia | 2 | 0.9 | 9 | 3.9 | 5.45 (1.14, 26.15) | 4 | 1.4 | 18 | 6.4 | 5.65 (1.86, 17.14) |  |
 P-trend |  |  |  |  | 0.015 |  |  |  |  | 0.41 |  |
Columnar cell lesionsb | |||||||||||
 None | 179 | 83.2 | 188 | 81.1 | 1.00 (ref) | 271 | 91.3 | 238 | 84.6 | 1.00 (ref) | 0.09 |
 Present with/without atypia | 36 | 16.9 | 44 | 18.9 | 1.09 (0.65, 1.82) | 26 | 8.7 | 43 | 15.4 | 2.08 (1.21, 3.58) |  |
 P-value |  |  |  |  | 0.73 |  |  |  |  | 0.008 |  |