Actigraphy measured sleep disruption as a predictor of survival in advanced breast cancer.

Abstract

9532 Background: Sleep disruption, prevalent in cancer patients and survivors, is associated with disrupted hormonal circadian rhythms and poor quality of life. Previous studies in cancer patients and survivors have pointed out the association between poor sleep and faster disease progression. However, until now these studies have been limited by their retrospective or correlational design, providing little resolution of the question of whether sleep disruption accelerates disease progression or whether disease progression dysregulates sleep, or whether a third factor might underlie the association between sleep dysregulation and disease progression. This study aimed to clarify this relationship by using a longitudinal research design to examine whether sleep disruption assessed at baseline predicts survival in women with metastatic breast cancer. Methods: We examined sleep quality and duration in 97 women diagnosed with metastatic breast cancer (mean age=54.6, SD=9.8) via wrist-worn actigraphy for 3 days and sleep diaries. Sleep quality was operationalized as poor sleep efficiency (the ratio of total asleep time to total time in bed * 100%). Results: As hypothesized, poor sleep efficiency was found to predict shorter survival (Hazard Ratio (HR), 0.96, 95% CI, 0.93 to 0.98, p<0.001) over 6 years. This relationship remained significant (HR, 0.94, CI, 0.91 to 0.97, p<.001) even after controlling for other known prognostic factors (age, ER status, cancer treatment, metastatic spread, cortisol levels, and depression). Conclusions: Our findings show that sleep dysregulation is a clear and significant independent prognostic factor for disease progression in metastatic breast cancer. Further research is needed to determine whether treating sleep disruption with cognitive behavioral therapy or medication can improve survival in metastatic breast cancer. Funded by P01AG018784, R01CA118867, K07CA132916.