Association between skeletal muscle mass and mammographic breast density

Area of Science:

• Oncology
• Radiology
• Body Composition Analysis

Background:

• Mammographic density (MD) and body mass index (BMI) have complex, often inverse relationships with breast cancer risk.
• Skeletal muscle mass index (SMI) offers a comprehensive measure of body composition, reflecting both fat and muscle percentages.
• The independent association between SMI and MD remains underexplored.

Purpose of the Study:

• To investigate the relationship between skeletal muscle mass index (SMI) and mammographic density (MD).
• To determine if SMI is an independent predictor of dense breasts, even after adjusting for BMI.

Main Methods:

• A cross-sectional study involving 143,456 women who underwent comprehensive health examinations between 2012 and 2016.
• Statistical analysis was performed to assess the association between SMI quartiles and MD, with adjustments for confounding factors including BMI.

Main Results:

• After adjusting for BMI and other confounders, women in the highest quartile of SMI had significantly higher odds of having dense breasts compared to those in the lowest quartile.
• Odds ratios for MD were 2.65 for premenopausal women and 2.39 for postmenopausal women when comparing the highest SMI quartile to the lowest.
• SMI was identified as a significant independent predictor of mammographic density.

Conclusions:

• Skeletal muscle mass index (SMI) is a significant predictor of mammographic density (MD) in women, independent of BMI.
• The association may stem from shared growth mechanisms between skeletal muscle and breast parenchymal tissue.
• Further research is warranted to elucidate the causal pathways linking muscularity, breast density, and breast cancer risk.