ASPO Abstracts
Adiposity change over the life course and mammographic breast density in postmenopausal women
Category: Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2020
Abstract Body:
Purpose: Mammographic breast density is a strong risk factor for breast cancer. Limited studies have investigated
the association between long-term adiposity change and mammographic breast density in postmenopausal
women, with conflicting results. Therefore, we comprehensively investigated the associations between body mass
index (BMI) change from ages 10, 18, and 30 to attained age with mammographic breast density in
postmenopausal women.
Methods: We analyzed data from 367 postmenopausal women recruited during screening mammography at
Washington University School of Medicine, St. Louis, between 2017 and 2018. We used multivariable linear
regressions to evaluate the associations of BMI change with volumetric percent density, dense volume, and non-
dense volume, assessed using Volpara.
Results: At time of mammogram, the mean age was 57.9 years and the mean BMI was 31.3 kg/m2. There were
strong inverse associations between BMI change during the life course and volumetric percent density, and the
strongest associations were observed for BMI gain from age 10 to age at mammogram with adjustment for
confounders (age at mammogram, family history of breast cancer, age at menarche, parity and age at first birth,
race, alcohol consumption, menopausal hormone therapy, and BMI at age 10). Compared to women who had a
BMI gain of 0.1-5 kg/m2 from age 10, women who had a BMI gain of 5.1-10 kg/m2 had a 24.4% decrease (95%
confidence interval [95% CI], 6.0%-39.2% decrease) in volumetric percent density; women who had a BMI gain of
10.1-15 kg/m2 had a 46.1% decrease (95% CI, 33.0%-56.7% decrease) in volumetric percent density; and women
who had a BMI gain of >15 kg/m2 had a 56.5% decrease (95% CI, 46.0%-65.0% decrease) in volumetric percent
density. Similar, but slightly attenuated associations were observed for BMI gain from ages 18 and 30 to attained
age and volumetric percent density. BMI gain over the life course was positively associated with non-dense
volume, but not dense volume.
Conclusions: BMI changes from ages 10, 18, and 30 to postmenopausal age were associated with mammographic
breast density in postmenopausal women. Mechanistic studies to investigate how long-term adiposity change,
especially since age 10 is associated with mammographic breast density are neede
Keywords: mammographic breast density, breast cancer, BMI change, weight change, postmenopausal