Distribution of nondietary factors among study subjects according to menopausal status
| Variables . | Premenopausal (n = 348) . | Postmenopausal (n = 253) . | ||
|---|---|---|---|---|
| Age (y) | 42.6 (5.8) | 57.8 (6.1) | ||
| BMI (kg/m2) | 22.1 (2.9) | 23.0 (3.0) | ||
| Education (y) | 2.7 (1.8) | 11.1 (2.1) | ||
| Age at menarche (y) | 12.8 (1.3) | 14.1 (1.7) | ||
| Age at first birth (y) | 25.3 (2.7) | 24.8 (2.9) | ||
| Age at menopause (y) | — | 49.2 (4.2) | ||
| Parity | 2.2 (0.8) | 2.3 (0.8) | ||
| Alcohol intake (mL/d) | 6.6 (17.1) | 4.7 (13.1) | ||
| Exercise (MET h/wk) | 31.0 (39.8) | 30.0 (44.1) | ||
| Current smokers (%) | 9.2 | 4.1 | ||
| Ex-smokers (%) | 5.2 | 2.8 | ||
| Family history of breast cancer | ||||
| Among first-degree relatives (%) | 4.6 | 4.0 | ||
| Breast feeding (%) | 90.1 | 90.0 | ||
| Variables . | Premenopausal (n = 348) . | Postmenopausal (n = 253) . | ||
|---|---|---|---|---|
| Age (y) | 42.6 (5.8) | 57.8 (6.1) | ||
| BMI (kg/m2) | 22.1 (2.9) | 23.0 (3.0) | ||
| Education (y) | 2.7 (1.8) | 11.1 (2.1) | ||
| Age at menarche (y) | 12.8 (1.3) | 14.1 (1.7) | ||
| Age at first birth (y) | 25.3 (2.7) | 24.8 (2.9) | ||
| Age at menopause (y) | — | 49.2 (4.2) | ||
| Parity | 2.2 (0.8) | 2.3 (0.8) | ||
| Alcohol intake (mL/d) | 6.6 (17.1) | 4.7 (13.1) | ||
| Exercise (MET h/wk) | 31.0 (39.8) | 30.0 (44.1) | ||
| Current smokers (%) | 9.2 | 4.1 | ||
| Ex-smokers (%) | 5.2 | 2.8 | ||
| Family history of breast cancer | ||||
| Among first-degree relatives (%) | 4.6 | 4.0 | ||
| Breast feeding (%) | 90.1 | 90.0 | ||
NOTE: Values are means (SD) or percentages. Breast feeding: self-reported, ever/never.
Abbreviation: MET, metabolic equivalents.