Table 4.
Medium potency estrogen-progestin therapy and risk of ductal and lobular breast cancer stratified by body mass index
| Recent BMI | Control group | Ductal cancer | Lobular cancer | |||||||
| Never use | Ever use | Never use | Ever use | Never use | Ever use | |||||
| No. | No. | No. | ORa (95%CI) | No. | ORa (95%CI) | No. | ORa (95%CI) | No. | ORa (95%CI) | |
| BMI <22 | 298 | 47 | 126 | 1.0 (Ref) | 49 | 2.0 (1.2–3.3) | 19 | 1.0 (Ref) | 12 | 3.4 (1.4–8.3) |
| BMI 22–27 | 895 | 132 | 420 | 1.1 (0.9–1.4) | 114 | 1.6 (1.1–2.3) | 46 | 0.8 (0.4–1.4) | 21 | 2.2 (1.0–4.6) |
| BMI >27 | 514 | 53 | 357 | 1.8 (1.4–2.3) | 52 | 1.9 (1.2–3.1) | 56 | 1.9 (1.1–3.3) | 10 | 2.2 (0.9–5.6) |
Exclusive use of medium potency estrogen-progestin therapy, users of more than one kind of menopausal hormone therapy were excluded. Women with unknown age at menopause were excluded. Recent = one year before data collection. aAdjusted for age, age at first birth and age at menopause. BMI, body mass index; CI, confidence interval; OR, odds ratio; Ref, reference category.