Association between skeletal muscle mass and mammographic breast density

Kwan Ho Lee,Seoung Wan Chae,Chan Heun Park,Yong Lai Park,Ji Sup Yun

doi:10.1038/s41598-021-96390-9

Abstract

Mammographic density (MD) of the breast and body mass index (BMI) are inversely associated with each other, but have inconsistent associations with respect to the risk of breast cancer. Skeletal muscle mass index (SMI) has been considered to reflect a relatively accurate fat and muscle percentage in the body. So, we evaluated the relation between SMI and MD. A cross-sectional study was performed in 143,456 women who underwent comprehensive examinations from 2012 to 2016. BMI was adjusted to analyze whether SMI is an independent factor predicting dense breast. After adjustment for confounding factors including BMI, the odds ratios for MD for the dense breasts was between the highest and lowest quartiles of SMI at 2.65 for premenopausal women and at 2.39 for postmenopausal women. SMI was a significant predictor for MD, which could be due to the similar growth mechanism of the skeletal muscle and breast parenchymal tissue. Further studies are needed to understand the causal link between muscularity, MD and breast cancer risk.

Highlights

Mammographic density (MD) reflects the relative amount of connective and epithelial tissue and fat tissue in the b reast[1,2]
This is the first study about the association between skeletal muscularity and MD, and we demonstrated that skeletal muscle mass index (SMI) was the most important predictor among the known predictors of MD by using relative weights (RW) analysis
SMI was an independent predictor of dense breasts after adjustment for known factors associated with MD, including age and body mass index (BMI)

Summary

Introduction

Mammographic density (MD) reflects the relative amount of connective and epithelial tissue (dense area) and fat tissue (non-dense area) in the b reast[1,2]. Increasing age and post-menopausal state with decreased estrogen levels is known to be a major determinant of M D15 Anthropometric factors, such as body mass index (BMI), waist–hip ratio, and waist circumference are known to be related to MD5–9. Studies are indicators of weight or mass including both muscle and fat, and these parameters do not reflect the respective amounts of each of muscle and adipose tissue. SMI indicates the proportion of skeletal muscle in the body, but are considered better markers for assessing adiposity and its metabolic consequences compared to BMI. This is because SMI reflects a relatively accurate fat percentage in the body. By attempting to adjust BMI in the analysis of the relationship between SMI and MD, it was intended to identify the cause of the paradoxical relationship between BMI and MD

Methods

Results

Conclusion