Table 3: Hazard ratios (HR) and 95% confidence intervals (CI) for the association of DXA-derived body fat measured at baseline with risk of incident, invasive breast cancer in postmenopausal women.

Quintiles for trend
12345

Whole body fat mass
 Cases7787112106121
 Person-years25,49025,18825,40424,93524,511
 Age- and energy-adjusted HR (95% CI)1.00
Ref.
1.14
(0.84–1.56)
1.47
(1.10–1.96)
1.42
(1.06–1.91)
1.69
(1.27–2.25)
0.0001
 Multivariable-adjusted HR (95% CI)a1.00
Ref.
1.18
(0.86–1.62)
1.57
(1.16–2.13)
1.47
(1.08–2.02)
1.88
(1.38–2.57)
<0.0001

Whole body percent fat
 Cases8196112100114
 Person-years25,73025,15725,13725,14124,364
 Age- and energy-adjusted HR (95% CI)1.00
Ref.
1.21
(0.90–1.62)
1.41
(1.06–1.88)
1.26
(0.94–1.69)
1.50
(1.13–1.99)
0.007
 Multivariable-adjusted HR (95% CI)a1.00
Ref.
1.21
(0.89–1.64)
1.48
(1.10–1.99)
1.28
(0.94–1.75)
1.60
(1.18–2.18)
0.004

Fat mass of trunk
 Cases/person-years799497106127
 Person-years 25,77025,35325,25224,68924,466
 Age- and energy-adjusted HR (95% CI)1.00
Ref.
1.21
(0.89–1.63)
1.24
(0.92–1.67)
1.41
(1.05–1.88)
1.74
(1.31–2.31)
<0.0001
 Multivariable-adjusted HR (95% CI)a1.00
Ref.
1.31
(0.96–1.78)
1.34
(0.98–1.83)
1.56
(1.15–2.14)
2.05
(1.50–2.79)
<0.0001

Fat mass of right leg
 Cases8186107109120
 Person-years24,66625,23125,52225,27624,835
 Age- and energy-adjusted HR (95% CI)1.00
Ref.
1.05
(0.78–1.43)
1.30
(0.98–1.74)
1.34
(1.01–1.79)
1.53
(1.15–2.04)
0.0008
 Multivariable-adjusted HR (95% CI)a1.00
Ref.
1.00
(0.73–1.36)
1.26
(0.93–1.69)
1.29
(0.95–1.74)
1.53
(1.14–2.07)
0.001

Fat mass of left leg
 Cases7891109101124
 Person-years24,58625,50125,32125,38624,736
 Age- and energy-adjusted HR (95% CI)1.00
Ref.
1.14
(0.84–1.54)
1.38
(1.03–1.85)
1.28
(0.95–1.72)
1.64
(1.24–2.19)
0.0004
 Multivariable-adjusted HR (95% CI)a1.00
Ref.
1.05
(0.77–1.43)
1.33
(0.99–1.79)
1.19
(0.87–1.62)
1.63
(1.21–2.20)
0.0007

Ratio of trunk fat mass to average of R and L leg fat mass
 Cases74117104104104
 Person-years25,93225,39125,38824,86423,955
 Age- and energy-adjusted HR (95% CI)1.00
Ref.
1.61
(1.20–2.15)
1.43
(1.06–1.93)
1.45
(1.08–1.96)
1.51
(1.12–2.04)
0.04
 Multivariable-adjusted HR (95% CI)a1.00
Ref.
1.68
(1.25–2.28)
1.51
(1.10–2.06)
1.60
(1.17–2.18)
1.77
(1.29–2.42)
0.004

Adjusted for age at enrollment, education, ethnicity, family history of breast cancer, age at menarche, age at first full-term birth, parity, age at menopause, oral contraceptive use, duration of hormone therapy, previous breast biopsy, physical activity, alcohol intake, pack-years of smoking, intake of energy, and randomization status.