Table 1. Baseline characteristics of cancer cases and matched controls.
| Controls | Overall cancer | Breast cancer | p1 | ||||
| (n = 250) | cases (n = 250) | cases (n = 154) | |||||
| Gender [n (%)] | |||||||
| Men | 80 (32.0) | 80 (32.0) | |||||
| Women | 170 (68.0) | 170 (68.0) | |||||
| Age (y)2 | 51.3±6.2 | 51.0±6.0 | 49.5±6.0 | 0.9 | |||
| BMI [n (%)] | 0.04 | ||||||
| <25 kg/m2 | 152 (60.8) | 166 (66.4) | 116 (75.3) | ||||
| 25 to <30 kg/m2 | 81 (32.4) | 57 (22.8) | 28 (18.2) | ||||
| ≥ 30 kg/m2 | 17 (6.8) | 27 (10.8) | 10 (6.5) | ||||
| Height (cm) | 165.0±7.8 | 165.8±7.8 | 163.1±5.9 | 0.1 | |||
| Intervention group [n (%)] | |||||||
| Yes | 115 (46.0) | 115 (46.0) | 75 (48.7) | ||||
| No (placebo) | 135 (54.0) | 135 (54.0) | 79 (51.3) | ||||
| Smoking status [n (%)] | 0.004 | ||||||
| Never smokers | 136 (54.4) | 121 (48.4) | 85 (55.2) | ||||
| Former smokers | 89 (35.6) | 75 (30.0) | 36 (23.4) | ||||
| Current smokers | 25 (10.0) | 54 (21.6) | 33 (21.4) | ||||
| Physical activity [n (%)] | 0.1 | ||||||
| Low | 51 (20.4) | 71 (28.4) | 49 (31.8) | ||||
| Moderate | 81 (32.4) | 72 (28.8) | 48 (31.2) | ||||
| High | 118 (47.2) | 107 (42.8) | 57 (37.0) | ||||
| Educational level [n (%)] | 0.3 | ||||||
| Primary | 67 (26.8) | 54 (21.6) | 27 (17.5) | ||||
| Secondary | 103 (41.2) | 104 (41.6) | 59 (38.3) | ||||
| University | 80 (32.0) | 92 (36.8) | 68 (44.2) | ||||
| Alcool intake (g/d) | 12.5±16.7 | 15.5±18.3 | 9.2±11.1 | 0.04 | |||
| Family history3 of any cancer (yes. %) | 83 (33.2) | 89 (35.6) | 45 (29.2) | 0.6 | |||
| Family history3 of breast cancer (yes. %)4 | 10 (4.0) | 25 (10.0) | 24 (15.6) | 0.001 | |||
| Menopausal status (yes. %)4 | 70 (28.0) | 72 (28.8) | 59 (38.3) | 0.8 | |||
| Use of hormonal treatment for menopause (yes. %)4 | 67 (26.8) | 71 (28.4) | 62 (40.3) | 0.6 | |||
| Number of biologic children4 | 1.9±1.1 | 1.9±1.2 | 2.0±1.2 | 0.6 | |||
1
P value for the comparison of overall cancer cases and controls by conditionnal logistic regression.
2
Mean ± SD (all such values).
3
In first or second degree relatives.
4
In women only.