Tailored Exercise Strategies and Mortality Among Breast Cancer Survivors

Area of Science:

• Oncology
• Exercise Science
• Epidemiology

Background:

• Guidelines recommend individualized exercise for cancer survivors, but data on long-term mortality benefits for breast cancer survivors are limited.
• Tailored exercise strategies adapt to individual patient characteristics over time.

Purpose of the Study:

• To estimate the impact of tailored exercise strategies on all-cause and breast cancer-specific mortality in breast cancer survivors.
• To emulate clinical trials using observational data to assess long-term outcomes.

Main Methods:

• A cohort study used target trial emulation to analyze data from the Pathways Study, including women from Kaiser Permanente Northern California (2006-2021).
• Two target trials were emulated: one mirroring the CHALLENGE trial and a second, more pragmatic trial of tailored exercise.
• Analyses involved comparing mortality risks associated with different exercise strategies.

Main Results:

• The first emulated trial indicated an aerobic exercise strategy was associated with an 8.0-percentage point lower 8-year all-cause mortality risk compared to a health education intervention.
• The second emulated trial showed tailored exercise strategies (60 min vigorous or 120 min moderate aerobic activity/week) were linked to a 3.1-percentage point lower 10-year all-cause mortality and a 2.4-percentage point lower 10-year breast cancer-specific mortality.
• Estimated 10-year all-cause mortality ranged from 18.1% to 21.2%, and breast cancer-specific mortality ranged from 7.6% to 10.0%.

Conclusions:

• Tailored exercise strategies demonstrated an association with reduced 10-year mortality among breast cancer survivors in this cohort study.
• The findings suggest that individualized exercise interventions may improve long-term survival for breast cancer patients.
• A randomized controlled trial is recommended to validate these observational findings.