Modifiable Lifestyle Factors and Triple-negative Breast Cancer Survival A Population-based Prospective Study

Background: Very little is known about the effect of modifiable lifestyle factors on outcomes of triple-negative breast cancer. We examined this association in a population-based prospective cohort study of patients with triple-negative breast cancer. Methods: A total of 518 women with confirmed triple-negative breast cancer, recruited by the Shanghai Breast Cancer Survival Study, completed 6-, 18-, 36-, and 60-month postdiagnosis surveys. We applied Cox proportional hazard models to evaluate the associations. Results: The mean age at diagnosis was 53.4 (standard deviation = 10.6) years old. After a median follow-up of 9.1 years (range: 0.6-11.8), 128 deaths and 112 recurrences were documented. Exercise during the first 60 months postdiagnosis was inversely associated with total mortality and recurrence/disease-specific mortality with adjusted hazard ratios (HRs) of 0.67 (95% confidence interval [CI] = 0.46, 0.96) and 0.58 (95% CI = 0.39, 0.86), respectively. Women with higher exercise-metabolic equivalent scores (7.6 metabolic equivalent-hours/week) and longer duration of exercise (2.5 hours/week) had lower risk of total and recurrence/disease-specific mortality than did nonexercisers. Compared with nontea drinkers, survival was better among women who were regular tea drinkers during the first 60 months for all cause (HR = 0.57, 95% CI = 0.34, 0.93) and recurrence/disease-specific mortality (HR = 0.54, 95% CI = 0.31, 0.96). There was no dose-response pattern for tea consumption. No interactions were observed for body mass index, menopausal status, and comorbidity. Conclusions: These findings show that postdiagnosis exercise and tea intake were associated with improved survival among women with triple-negative breast cancer.