Physical Activity From Adolescence Through Midlife and Associations With Body Mass Index and Endometrial Cancer Risk

Area of Science:

• Epidemiology
• Oncology
• Public Health

Background:

• Physical activity is linked to reduced endometrial cancer risk.
• The mediating role of midlife body mass index (BMI) in this association requires further clarification.

Purpose of the Study:

• To examine the association between long-term physical activity patterns and endometrial cancer risk.
• To determine the extent to which midlife BMI mediates the relationship between physical activity and endometrial cancer.

Main Methods:

• Utilized data from 67,705 women (aged 50-71) in the National Institutes of Health-AARP Diet and Health Study.
• Identified five distinct physical activity patterns from adolescence to midlife.
• Employed Cox regression and mediation analysis to assess associations and BMI's mediating role.

Main Results:

• Women with maintained high or increased physical activity showed a 19-26% lower risk of endometrial cancer.
• These activity levels were also associated with a 50-77% lower risk of midlife obesity.
• Midlife BMI statistically mediated 55.5% to 62.7% of the physical activity-endometrial cancer association.

Conclusions:

• Both sustained and newly adopted physical activity in adulthood contribute to obesity prevention.
• Physical activity is crucial for reducing endometrial cancer risk, partly through its impact on BMI.