Sleep quality after initial chemotherapy for breast cancer.

OBJECTIVE

The goal of this study is to characterize sleep quality and quantity prior to and in the first three nights after initial chemotherapy for breast cancer.

METHODS

This study makes use of secondary analysis of data from two separate randomized clinical trials (RCT) of behavioral interventions to improve fatigue and sleep. Patients came from two comprehensive cancer centers, three clinical cancer centers, and 10 community clinics in five states. Participants were women with stage I-IIIA breast cancer treated with anthracycline and/or cyclophosphamide-based regimens.

RESULTS

Baseline data from each RCT were used in the analysis. Sixty-five percent of women self-reported poor sleep in the month preceding chemotherapy using the Pittsburgh Sleep Quality Index (PSQI) score >5. Three nights of actigraphy data indicated a wide range of sleep experience with an average of 10 awakenings and time (minutes) awake after sleep onset (WASO-M) averaging 61 min per night. The first night's sleep was the worst. There was no statistically significant relationship between self-reported poor sleep and sleep measures obtained by actigraphy. Women with poor sleep at baseline (global PSQI >5) had significantly lower (p < 0.001) physical (PCS) and mental (MCS) health status. However, neither the PCS nor MCS was associated with any of the average actigraphy sleep parameters or night 1 parameters in the aggregated sample. Increasing age was also associated with poorer sleep.

CONCLUSIONS

A high percent of women with breast cancer begin chemotherapy with disturbed sleep and the initial nights after chemotherapy are characterized by sleep fragmentation that disrupts sleep maintenance. Interventions should focus on strategies to decrease the number and duration of night awakenings. Further research is needed to identify predictors of poor sleep during this time.