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Determinants of Mammographic Density Change.
JNCI Cancer Spectrum
|July 31, 2019
Summary
Breast cancer risk factors like BMI and physical activity influence mammographic density (MD) changes over time. Leaner, active women experience greater annual MD reduction, highlighting lifestyle
Area of Science:
- Radiology and Oncologic Imaging
- Epidemiology
- Women's Health
Background:
- Mammographic density (MD) is a significant breast cancer risk factor.
- Understanding how risk factors affect MD changes with age is crucial for risk assessment.
Purpose of the Study:
- To investigate the association between breast cancer risk factors and baseline MD.
- To examine how these factors influence the change in MD over time across different age groups.
Main Methods:
- A cohort study of 31,782 Swedish women aged 40-70 years.
- Assessment of lifestyle and reproductive risk factors via questionnaire.
- Measurement of MD using the STRATUS method; statistical analysis using linear regression.
Main Results:
- Established breast cancer risk factors, excluding oral contraceptive use, correlated with baseline MD.
- Average annual MD change was -1.0 cm².
- Body Mass Index (BMI) and physical activity significantly impacted MD change; leaner and more active women showed greater MD reduction.
Conclusions:
- Most breast cancer risk factors are linked to baseline MD, but only age, BMI, and physical activity determine MD changes.
- These findings emphasize the role of modifiable factors in breast density changes over time.
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