Table 5.

Adjusted mean percent density (%) by categorical covariates among B4BCP study participants (232 postmenopausal women)

nMean (SE)P*
Level of education
    Attended or graduated high school4837.0 (2.3)0.29
    Some college or technical school7232.7 (1.8)
    Graduated college11233.3 (1.5)
Parity
    Nulliparous3538.8 (2.6)0.04
    Parous19733.0 (1.1)
Reason periods stopped
    Natural menopause18434.6 (1.1)0.17
    Surgical menopause4831.1 (2.2)
Use of combined hormone therapy
    Never15231.9 (1.2)<0.01
    Ever8037.7 (1.7)
Use of estrogen replacement therapy
    Never17034.6 (1.2)0.24
    Ever6231.8 (2.0)
Breast cancer among first-degree relatives*
    No16734.0 (1.2)0.33
    Yes4731.5 (2.3)
Frequency of soy food or supplement intake
    <1/wk18933.1 (1.3)0.19
    ≥1/wk4337.0 (2.7)
Equol producer
    No15733.1 (1.2)0.27
    Yes7535.5 (1.8)
  • NOTE: Data were adjusted for age and BMI.

  • * P values were obtained using one-way ANOVA and reflect differences between groups.