The Relationship between Body Mass Index and Mammographic Density during a Premenopausal Weight Loss Intervention Study

Abstract

We evaluated the association between short-term change in body mass index (BMI) and breast density during a 1 year weight-loss intervention (Manchester, UK). We included 65 premenopausal women (35–45 years, ≥7 kg adult weight gain, family history of breast cancer). BMI and breast density (semi-automated area-based, automated volume-based) were measured at baseline, 1 year, and 2 years after study entry (1 year post intervention). Cross-sectional (between-women) and short-term change (within-women) associations between BMI and breast density were measured using repeated-measures correlation coefficients and multivariable linear mixed models. BMI was positively correlated with dense volume between-women (r = 0.41, 95%CI: 0.17, 0.61), but less so within-women (r = 0.08, 95%CI: −0.16, 0.28). There was little association with dense area (between-women r = −0.12, 95%CI: −0.38, 0.16; within-women r = 0.01, 95%CI: −0.24, 0.25). BMI and breast fat were positively correlated (volume: between r = 0.77, 95%CI: 0.69, 0.84, within r = 0.58, 95%CI: 0.36, 0.75; area: between r = 0.74, 95%CI: 0.63, 0.82, within r = 0.45, 95%CI: 0.23, 0.63). Multivariable models reported similar associations. Exploratory analysis suggested associations between BMI gain from 20 years and density measures (standard deviation change per +5 kg/m2 BMI: dense area: +0.61 (95%CI: 0.12, 1.09); fat volume: −0.31 (95%CI: −0.62, 0.00)). Short-term BMI change is likely to be positively associated with breast fat, but we found little association with dense tissue, although power was limited by small sample size.

Effect of Metformin on Breast Density in Overweight/Obese Premenopausal Women

“… 7 Some studies have suggested that the risk of breast cancer in women with an increased breast density is 4–6 times higher than that in women without an increased breast density. 15 Similar conclusions have been obtained in the Chinese population. 5 Moreover, some studies have indicated that the breast density of premenopausal women in China is higher than that in premenopausal women in Western countries.…”

Special Issue “Gynaecological Cancers Risk: Breast Cancer, Ovarian Cancer and Endometrial Cancer”

“…Dibden et al [ 13 ] undertook a worldwide review and meta-analysis of cohort studies evaluating mammography-based breast cancer screening programmes, and found a 22% reduction in breast cancer mortality. Atakpa et al [ 14 ] evaluated the association of weight loss (using diet and exercise) for breast cancer risk reduction with changes in breast density in pre-menopausal women. While short-term reduction in BMI is associated with a reduction in fatty breast tissue, it was not associated with changes in glandular or dense breast tissue, indicating that breast density may not capture any weight-loss associated reduction in breast cancer risk.…”