Abstract 4254: Associations of sleep, quality of life and energy level with breast cancer mortality and recurrence: The Shanghai Breast Cancer Survival Study

Background: Sleep disorder is highly prevalent among breast cancer patients. Whether sleep disorder is associated with breast cancer prognosis has rarely been investigated. The objective of this study is to prospectively assess the association of self-reported sleep difficulty and sleep quality with total mortality and breast-cancer specific mortality/recurrence in the Shanghai Breast Cancer Survival Study. Methods: This study included 4,219 women with stage I-III breast cancer diagnosed at an age between 20 to 75 years. Information on sleep attributes was collected at approximately 18 months and 36 months after breast cancer diagnosis. Information on disease recurrence and survival status was obtained via in-person follow-up and via record linkage with vital statistics registry data. Cox proportional hazard model was used to derive hazard ratios (HR) and confidence intervals (CIs) for all-cause mortality and breast cancer-specific mortality/recurrence. Stratified analyses according to self-reported overall quality of life, depression and energy level assessed at 18 months were also conducted. Results: During a median follow-up of 9.8 years (range: 0.1-12.2 years), 757 deaths due to any causes and 672 breast cancer recurrences or related deaths were recorded after the 18-month post-diagnosis survey. Sleep difficulty and low sleep quality were not significantly associated with total or breast-cancer specific mortality/recurrence. The respective HRs were 0.98 (95% CI: 0.79, 1.22) and 1.01 (95% CI: 0.77, 1.31) for total mortality and 1.04 (95% CI: 0.82, 1.31) and 0.93 (95% CI: 0.69, 1.26) for breast cancer-specific mortality/recurrence. On the other hand, low quality of life, depression and low energy level were significantly associated with increased total mortality, with HRs of 3.19 (2.45, 4.15), 1.61 (1.21, 2.14) and 1.53 (1.23, 1.91), respectively. These three factors did not modify the association of sleep measurements with breast cancer outcomes (all P-interactions > 0.10). Conclusions: In a large population-based cohort study, we did not observe any significant association of sleep difficulty and poor sleep quality with increased risk of death and recurrence in breast cancer patients. Instead, low quality of life and energy level were found to be associated with disease prognosis and thus they could be important indicators for targeting population with poor breast cancer prognosis. Citation Format: Jingjing Zhu, Pingping Bao, Hui Cai, Liang Shi, Ying Zheng, Wei Zheng, Xiao-ou Shu. Associations of sleep, quality of life and energy level with breast cancer mortality and recurrence: The Shanghai Breast Cancer Survival Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4254.