Table 1.

Baseline characteristics of the subcohort by Cyp17 genotype

CharacteristicsGenotype
A1/A1 166 (44.5%)A1/A2 157 (42.1%)A2/A2 50 (13.4%)
Person-years of follow-up59,86256,71618,148
Age at recruitment, median (range)57 (40-65)58 (43-66)58 (50-65)
Height, mean (SD)162.1 (5.7)161.9 (6.2)162.1 (6.8)
Weight, mean (SD)67.8 (10.1)68.4 (12.1)69.5 (10.1)
BMI
    <25 kg/m260 (36.1%)62 (39.5%)14 (28.0%)
    ≥25 kg/m2106 (63.9%)95 (60.5%)36 (72.0%)
Age at menarche*, mean (SD)13.4 (1.5)13.8 (1.5)13.1 (1.8)
Nulliparity (%)21.719.720.0
Age at first full-term pregnancy, median (range)27.0 (18-53)27.0 (18-42)27.5 (18-38)
Age at menopause, median (range)50 (34-58)50 (39-60)50 (37-56)
Family history of breast cancer (% yes)6.27.112.0
Oral contraceptive use (% ever)4.44.92.1
Hormone replacement therapy (% current use)11.67.60
Smoking (% ever)25.325.534.0
  • * Age at menarche was missing for 53.2% (n = 237).

  • At least a mother or one sister with breast cancer.