Table 1.
Age-adjusted characteristics of study participants, by case-control status
| Characteristic | Controls n=375 | Cases n=101 | P for difference |
|---|---|---|---|
| Mean (SD) | |||
| Age (years)a | 52.47 (8.62) | 53.92 (8.68) | NA |
| Age at menarche (years) | 12.58 (1.37) | 12.27 (1.43) | 0.35 |
| Body Mass Index (kg/m2) | 24.77 (4.66) | 23.88 (3.73) | 0.91 |
| Age at menopause (years) | 49.06 (5.19) | 50.15 (2.31) | 0.61 |
| Alcohol, g/day | 5.166 (8.78) | 3.438 (4.22) | 0.83 |
| CD44 normal TDLU Epithelium % | 41.24 (36.58) | 38.04 (34.12) | 0.13 |
| CD44 normal TDLU Stroma % | 19.09 (27.92) | 17.09 (26.4) | 0.24 |
| CD24 normal TDLU Epithelium % | 29.32 (23.13) | 28.44 (21.54) | 0.28 |
| CD24 normal TDLU Stroma % | 9.001 (14.423) | 7.122 (9.831) | 0.88 |
| ALDH1A1 normal TDLU Epithelium % | 27.21 (19.18) | 27.52 (20.84) | 0.03 |
| ALDH1A1 normal TDLU Stroma % | 12 (13.8) | 12.32 (13.14) | 0.29 |
| Percentages | |||
| Parity/age at first birth | 0.57 | ||
| Nulliparous | 9 | 8 | |
| Parous, age <25 years | 50 | 43 | |
| Parous, age ≥25 years | 40 | 48 | |
| Family history of breast cancer | 11 | 24 | 0.32 |
| Benign breast disease | 0.18 | ||
| Non-proliferative | 31 | 24 | |
| Proliferative without atypia | 56 | 51 | |
| Proliferative with atypia | 13 | 25 | |
| Never smoked | 49 | 36 | 0.50 |
| Past smoker | 5 | 6 | |
| Current smoker | 13 | 17 | |
| Premenopausal | 40 | 39 | 0.82 |
| Postmenopausal/never used MHT | 25 | 27 | |
| Postmenopausal/past MHT | 14 | 14 | |
| Postmenopausal/current MHT | 19 | 16 |
a
Value is not age adjusted.