Table 1.

Population characteristics across quartiles of the ERDP score, Sister Study, 2003–2009

ERDP quartile (score range)
1st2nd3rd4th
(−8.2344 to −0.4442)(−0.4441 to −0.0584)(−0.0583 to 0.3467)(0.3468 to 4.6661)
n9,4819,4829,4819,481
Breast cancer casesTotal520474484490
Invasive393368350373
Invasive ER+308268250272
Invasive ER47465256
ERDP score (mean ± SD)−0.90 ± 0.48−0.24 ± 0.110.13 ± 0.120.82 ± 0.47
Age (mean ± SD)58.3 ± 7.358.1 ± 7.557.2 ± 7.856.0 ± 7.6
BMI (kg/m2; mean ± SD)27.0 ± 5.527.4 ± 5.628.0 ± 6.028.7 ± 6.6
BMI at age 30 (kg/m2; mean ± SD)22.7 ± 3.322.7 ± 3.323.0 ± 3.523.4 ± 4.0
Total caloric intake (kcal/day)1,601 ± 5901,439 ± 5321,527 ± 5351,908 ± 649
MET-hours/week (mean ± SD)53.4 ± 31.951.1 ± 31.049.6 ± 30.949.8 ± 31.1
Age at menarche (mean ± SD)12.6 ± 1.512.6 ± 1.512.6 ± 1.512.7 ± 1.6
Age at menopause (mean ± SD)50.3 ± 5.850.1 ± 5.949.9 ± 6.149.8 ± 5.9
Number of relatives with family history (mean ± SD)1.27 ± 0.591.28 ± 0.591.27 ± 0.581.26 ± 0.57
Parity (mean ± SD)1.95 ± 1.352.01 ± 1.352.02 ± 1.371.96 ± 1.37
Nulliparous (%)18.216.617.218.6
PHT status (%)
Never44.645.8 48.152.0
Former: estrogen + progesterone24.422.721.719.4
Former: estrogen only16.817.115.714.8
Former: unknown what type2.32.32.42.4
Current: estrogen + progesterone5.25.05.14.6
Current: estrogen only6.77.1 7.0 6.8
Race/ethnicity (%)
White, non-Hispanic85.684.785.086.4
Black, non-Hispanic8.38.17.95.5
Hispanic2.84.34.55.2
Asian0.90.70.50.3
Other2.42.22.12.6
Alcohol (%)
Abstainer17.818.619.921.1
≤1 drink/day70.769.869.567.0
>1 drink/day11.511.610.611.9
Smoking (%)
Current7.97.87.58.1
Former41.838.535.035.1
Never50.353.757.556.8
Education (%)
<HS0.91.11.21.2
HS grad or some college32.435.036.234.8
College grad39.639.039.741.3
Postgraduate27.124.922.922.7
Hysterectomy (%)
No65.665.565.066.8
Yes34.434.535.033.2
Non-whole/refined grains (oz/day; mean ± SD)2.32 ± 1.262.39 ± 1.232.82 ± 1.343.94 ± 1.98
Tomatoes (cups/day; mean ± SD)0.24 ± 0.170.23 ± 0.170.25 ± 0.190.35 ± 0.28
Other vegetables (cups/day; mean ± SD)0.63 ± 0.510.44 ± 0.330.40 ± 0.290.45 ± 0.31
Cruciferous vegetables (cups/day; mean ± SD)0.23 ± 0.270.20 ± 0.240.22 ± 0.250.29 ± 0.41
Cheese (cups/day; mean ± SD)0.26 ± 0.210.28 ± 0.210.36 ± 0.240.66 ± 0.41
Yogurt (cups/day; mean ± SD)0.23 ± 0.280.10 ± 0.140.08 ± 0.120.06 ± 0.11
Fish/shellfish high in ω-3 fatty acids (oz/day; mean ± SD)0.18 ± 0.230.14 ± 0.170.13 ± 0.170.15 ± 0.22
Fish/shellfish low in ω-3 fatty acids (oz/day; mean ± SD)0.58 ± 0.630.40 ± 0.360.38 ± 0.340.42 ± 0.41
Franks and luncheon meats (oz/day; mean ± SD)0.37 ± 0.320.41 ± 0.330.51 ± 0.370.78 ± 0.59
Nuts and seeds (oz/day; mean ± SD)2.11 ± 2.261.31 ± 1.331.14 ± 1.171.20 ± 1.20
Coffee (cups/day; mean ± SD)2.19 ± 1.681.58 ± 1.401.19 ± 1.281.02 ± 1.25
  • Abbreviations: HS, high school; MET, metabolic equivalent of task; PHT, postmenopausal hormone therapy.