Table 2. Associations of HRT ever-use and duration of use with breast cancer risk by BMI among women with natural menopause, the Nashville Breast Health Study.
| Variables | BMI < 25 | BMI ≥ 25 | |||
|---|---|---|---|---|---|
| Case/control | aOR (95%CI) | Case/control | aOR (95%CI) | bp for interaction | |
| HRT use | |||||
| Never | 63/99 | 1.00 (ref.) | 131/119 | 1.00 (ref.) | |
| Ever | 186/152 | 1.95 (1.32-2.88) | 213/214 | 0.91 (0.67-1.25) | 0.001 |
| Duration of use | |||||
| < 5 years | 47/48 | 1.67 (0.99-2.81) | 63/75 | 0.76 (0.50-1.16) | |
| 5-9 years | 47/37 | 1.93 (1.13-3.31) | 60/48 | 1.14 (0.72-1.80) | 0.012 |
| ≥ 10 years | 71/51 | 2.13 (1.26-3.59) | 61/56 | 1.03 (0.65-1.62) | |
| p for trend | P = 0.002 | P = 0.706 | |||
a
Adjusted for age and education.
b
Interaction between BMI (<25 or ≥25) and HRT ever-use or duration of use for overall risk of breast cancer.