Table 3.
Cases | Controls | |||||||
---|---|---|---|---|---|---|---|---|
n | % | n | % | OR1 | 95% CI | OR2 | 95% CI | |
Premenopausal women | ||||||||
BMI 1 year before (kg/m2) | ||||||||
<25 | 23 | 17.3 | 45 | 20.9 | 1.00 | Ref | 1.00 | Ref |
25–<30 | 33 | 24.8 | 45 | 20.9 | 1.49 | 0.73, 3.02 | 1.91 | 0.91, 4.04 |
30–<35 | 37 | 27.8 | 50 | 23.3 | 1.51 | 0.76, 3.00 | 1.40 | 0.67, 2.90 |
35–<40 | 19 | 14.3 | 43 | 20.0 | 0.77 | 0.36, 1.66 | 0.70 | 0.31, 1.57 |
≥40 | 21 | 15.8 | 32 | 14.9 | 1.21 | 0.55, 2.64 | 1.28 | 0.56, 2.92 |
p for trend | 0.72 | 0.57 | ||||||
Per 5 kg/m2 | 0.99 | 0.88, 1.11 | 0.97 | 0.86, 1.10 | ||||
Weight gain (kg)2 | ||||||||
Q1 (0–13.5) | 43 | 34.7 | 63 | 31.0 | 1.00 | Ref | 1.00 | Ref |
Q2 (13.6–23.9) | 27 | 21.8 | 55 | 27.1 | 0.63 | 0.33, 1.18 | 0.80 | 0.41, 1.58 |
Q3 (24.0–36.2) | 27 | 21.8 | 35 | 17.2 | 0.91 | 0.47, 1.79 | 1.07 | 0.53, 2.19 |
Q4 (≥36.3) | 27 | 21.8 | 50 | 24.6 | 0.64 | 0.33, 1.23 | 0.73 | 0.37, 1.47 |
p for trend | 0.29 | 0.48 | ||||||
Per 5 kg | 0.98 | 0.92, 1.05 | 0.99 | 0.93, 1.06 | ||||
Postmenopausal women | ||||||||
BMI 1 year before (kg/m2) | ||||||||
<25 | 42 | 11.7 | 79 | 16.4 | 1.00 | Ref | 1.00 | Ref |
25–<30 | 90 | 25.1 | 138 | 28.7 | 1.15 | 0.72, 1.83 | 1.17 | 0.73, 1.89 |
30–<35 | 98 | 27.3 | 132 | 27.4 | 1.35 | 0.85, 2.14 | 1.37 | 0.85, 2.19 |
35–<40 | 61 | 17.0 | 69 | 14.4 | 1.60 | 0.96, 2.68 | 1.65 | 0.97, 2.78 |
≥40 | 68 | 18.9 | 63 | 13.1 | 1.96 | 1.17, 3.27 | 1.94 | 1.14, 3.30 |
p for trend | 0.003 | 0.004 | ||||||
Per 5 kg/m2 | 1.16 | 1.06, 1.27 | 1.15 | 1.05, 1.26 | ||||
Weight gain (kg)2 | ||||||||
Q1 (0–13.5) | 55 | 16.2 | 105 | 23.0 | 1.00 | Ref | 1.00 | Ref |
Q2 (13.6–23.9) | 88 | 26.0 | 120 | 26.3 | 1.40 | 0.91, 2.16 | 1.50 | 0.97, 2.34 |
Q3 (24.0–36.2) | 76 | 22.4 | 123 | 26.9 | 1.17 | 0.75, 1.81 | 1.24 | 0.79, 1.94 |
Q4 (≥36.3) | 120 | 35.4 | 109 | 23.8 | 2.08 | 1.36, 3.17 | 2.10 | 1.37, 3.23 |
p for trend | 0.001 | 0.001 | ||||||
Per 5 kg | 1.06 | 1.02, 1.10 | 1.06 | 1.01, 1.10 | ||||
Postmenopausal non-HT users | ||||||||
BMI 1 year before (kg/m2) | ||||||||
<25 | 28 | 10.5 | 60 | 16.0 | 1.00 | Ref | 1.00 | Ref |
25–<30 | 65 | 24.4 | 106 | 28.3 | 1.23 | 0.71, 2.14 | 1.24 | 0.70, 2.18 |
30–<35 | 73 | 27.4 | 102 | 27.2 | 1.47 | 0.85, 2.53 | 1.45 | 0.83, 2.53 |
35–<40 | 48 | 18.1 | 54 | 14.4 | 1.81 | 0.99, 3.30 | 1.79 | 0.97, 3.31 |
≥40 | 52 | 19.6 | 53 | 14.1 | 1.96 | 1.08, 3.56 | 1.84 | 0.99, 3.41 |
p for trend | 0.009 | 0.02 | ||||||
Per 5 kg/m2 | 1.18 | 1.07, 1.31 | 1.16 | 1.05, 1.29 | ||||
Weight gain (kg)2 | ||||||||
Q1 (0–13.5) | 35 | 14.1 | 85 | 23.9 | 1.00 | Ref | 1.00 | Ref |
Q2 (13.6–23.9) | 65 | 26.1 | 88 | 24.8 | 1.79 | 1.07, 3.00 | 1.93 | 1.14, 3.28 |
Q3 (24.0–36.2) | 57 | 22.9 | 98 | 27.6 | 1.36 | 0.81, 2.29 | 1.44 | 0.85, 2.46 |
Q4 (≥36.3) | 92 | 36.9 | 84 | 23.7 | 2.56 | 1.56, 4.22 | 2.54 | 1.52, 4.24 |
p for trend | 0.001 | 0.001 | ||||||
Per 5 kg | 1.07 | 1.02, 1.12 | 1.06 | 1.01, 1.12 |
OR: Odds Ratio; CI: Confidence Interval.
OR1: Adjusted for age, education (high school or less, some post-high school training, college or graduate degree), region (south- and mid-Atlantic, South central, Midwest). OR2: Further adjusted for parity (0, 1–2, >2), oral contraceptive use (never, <60 mo, ≥60 mo), age at menarche (<12, 12–13, >13, menopause status (pre, post-menopausal), tubal ligation (yes, no), family history of breast/ovarian cancer (yes, no). Weight gain further adjusted for weight at age 18.
p for interaction between menopausal status and BMI 1 year before or weight gain is 0.04 or 0.09 respectively.
16 cases and 4 controls had missing data for weight at age 18 and weight gain.