Body Fat and Breast Cancer Risk in Postmenopausal Women: A Longitudinal Study
Table 5
Hazard ratios (HR) and 95% confidence intervals (CI) from time-dependent covariate analysis of the association of DXA-derived body fat with risk of incident, invasive breast cancer in postmenopausal women.
Quintiles
for trend
1
2
3
4
5
Average value:
Whole body fat mass
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.05 (0.76–1.44)
1.31 (0.97–1.77)
1.25 (0.92–1.70)
1.53 (1.13–2.07)
0.003
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.04 (0.75–1.44)
1.37 (1.00–1.86)
1.29 (0.93–1.78)
1.60 (1.16–2.21)
0.002
Whole body percent fat
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.00 (0.73–1.37)
1.33 (0.99–1.78)
1.06 (0.78–1.44)
1.47 (1.10–1.97)
0.01
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
0.99 (0.72–1.38)
1.37 (1.01–1.85)
1.08 (0.78–1.49)
1.52 (1.11–2.08)
0.01
Fat mass of trunk
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.24 (0.90–1.70)
1.21 (0.89–1.66)
1.46 (1.07–1.99)
1.82 (1.34–2.47)
<0.0001
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.33 (0.96–1.85)
1.29 (0.93–1.79)
1.64 (1.19–2.27)
2.07 (1.49–2.87)
<0.0001
Fat mass of right leg
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.05 (0.77–1.43)
1.23 (0.91–1.65)
1.21 (0.90–1.64)
1.69 (1.27–2.26)
0.0003
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
0.96 (0.70–1.32)
1.19 (0.88–1.61)
1.12 (0.82–1.54)
1.60 (1.18–2.16)
0.002
Fat mass of left leg
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.01 (0.74–1.38)
1.29 (0.96–1.73)
1.09 (0.81–1.48)
1.66 (1.25–2.21)
0.0008
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
0.92 (0.67–1.27)
1.25 (0.93–1.69)
1.00 (0.73–1.37)
1.55 (1.15–2.09)
0.005
Ratio of trunk fat mass to average of R and L leg fat mass
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.43 (1.06–1.93)
1.24 (0.91–1.68)
1.21 (0.89–1.65)
1.37 (1.01–1.87)
0.24
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.50 (1.10–2.04)
1.30 (0.94–1.79)
1.32 (0.95–1.82)
1.63 (1.18–2.25)
0.03
Value 2–4 years prior to diagnosis:
Whole body fat mass
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.18 (0.80–1.74)
0.86 (0.56–1.30)
1.03 (0.69–1.53)
1.55 (1.06–2.25)
0.07
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.16 (0.78–1.74)
0.94 (0.61–1.44)
1.04 (0.68–1.59)
1.67 (1.12–2.49)
0.04
Whole body percent fat
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.05 (0.70–1.56)
1.18 (0.81–1.73)
0.85 (0.56–1.28)
1.30 (0.89–1.90)
0.41
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.07 (0.71–1.61)
1.22 (0.82–1.81)
0.88 (0.57–1.36)
1.35 (0.90–2.02)
0.33
Fat mass of trunk
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.31 (0.88–1.93)
0.91 (0.60–1.40)
1.28 (0.86–1.90)
1.60 (1.08–2.36)
0.04
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.39 (0.93–2.09)
1.02 (0.66–1.59)
1.40 (0.92–2.14)
1.83 (1.21–2.79)
0.01
Fat mass of right leg
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.19 (0.81–1.76)
1.11 (0.75–1.65)
0.91 (0.60–1.39)
1.56 (1.07–2.26)
0.12
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.11 (0.75–1.66)
1.08 (0.72–1.61)
0.85 (0.55–1.32)
1.50 (1.02–2.22)
0.17
Fat mass of left leg
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.17 (0.79–1.74)
1.24 (0.84–1.82)
0.95 (0.63–1.44)
1.50 (1.03–2.19)
0.14
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.09 (0.73–1.62)
1.21 (0.82–1.80)
0.89 (0.58–1.36)
1.43 (0.96–2.13)
0.23
Ratio of trunk fat mass to average of R and L leg fat mass
Age- and energy-adjusted HR (95% CI)
1.00 Ref.
1.28 (0.87–1.90)
1.14 (0.76–1.70)
1.20 (0.81–1.78)
1.15 (0.77–1.72)
0.69
Multivariable-adjusted HR (95% CI)a
1.00 Ref.
1.33 (0.89–2.00)
1.21 (0.79–1.83)
1.29 (0.85–1.95)
1.37 (0.90–2.09)
0.22
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.
