Table 1. Demographic characteristics of women in the discovery set (N = 871).
| All women(N = 871) | Breast cancer-free women (N = 573) | Breast cancer cases(N = 298) | ||||
|---|---|---|---|---|---|---|
| N | (%) | N | (%) | N | (%) | |
| BMI | ||||||
| <25 | 371 | (42.6) | 245 | (42.8) | 126 | (42.3) |
| 25–29 | 226 | (25.9) | 153 | (26.7) | 73 | (24.5) |
| 29–35 | 159 | (18.3) | 98 | (17.1) | 61 | (20.5) |
| 35+ | 115 | (13.2) | 77 | (13.4) | 38 | (12.7) |
| Menopausal Status | ||||||
| Pre-menopausal | 328 | (37.7) | 219 | (38.2) | 109 | (36.6) |
| Post-menopausal | 543 | (62.3) | 354 | (61.8) | 189 | (63.4) |
| Smoking Status | ||||||
| Never | 458 | (52.6) | 294 | (51.3) | 164 | (55.0) |
| Social | 20 | (2.3) | 15 | (2.6) | 5 | (1.7) |
| Past | 331 | (38.0) | 222 | (38.7) | 109 | (36.6) |
| Current | 62 | (7.1) | 42 | (7.3) | 20 | (6.7) |
| Ever used an NSAID regularly a | ||||||
| No | 381 | (43.7) | 251 | (43.8) | 130 | (43.6) |
| Yes | 490 | (56.3) | 322 | (56.2) | 168 | (56.4) |
| Mean age at baseline | ||||||
| Mean (SD) | 55.1 | (9.1) | 54.6 | (8.9) | 56.1 | (9.2) |
| Total years of use reported among users | ||||||
| Mean (SD) | 7.7 | (9.3) | 7.8 | (9.6) | 7.6 | (8.7) |
| Total pill-years of use reported among all users | ||||||
| Mean (SD) | 27.9 | (68.7) | 28.2 | (67.7) | 27.2 | (70.6) |
| Used an NSAID daily in the past 12 months | ||||||
| No | 542 | (62.2) | 363 | (63.4) | 179 | (60.1) |
| Yes | 329 | (37.8) | 210 | (36.6) | 119 | (39.9) |
aused an NSAID > = 3 times a week for 3 or more months