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

Abstract

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. 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. 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. These findings show that postdiagnosis exercise and tea intake were associated with improved survival among women with triple-negative breast cancer.