Table 1.

Distribution of nondietary factors among study subjects according to menopausal status

VariablesPremenopausal (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)
Parity2.2 (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 (%)9.24.1
Ex-smokers (%)5.22.8
Family history of breast cancer
    Among first-degree relatives (%)4.64.0
Breast feeding (%)90.190.0
  • NOTE: Values are means (SD) or percentages. Breast feeding: self-reported, ever/never.

  • Abbreviation: MET, metabolic equivalents.