ASPO Abstracts
The Impact of Breast Cancer on Sleep: The Study of Women's Health Across the Nation (SWAN)
Category: Survivorship & Health Outcomes/Comparative Effectiveness Research, Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2018
Abstract Body:
Purpose: Sleep disturbances are commonly reported by breast cancer survivors (BCS), but how long such disturbances last and how they compare to people without cancer is less clear. This study seeks to examine sleep disturbances in the 5 years pre- and post- diagnosis among BCS compared to women without a history of cancer. Methods: Analyses included 129 women with incident breast cancer during a 20-year followup in the Study of Women’s Health Across the Nation (SWAN), a multiethnic/racial cohort of women originally recruited when aged 42-55 years old. A similarly-aged group of 1987 cancer-free women (CFW) randomly assigned a diagnosis date to match the BCS distribution was also examined. Women self-reported the frequency of the following in the past 2 weeks: trouble falling asleep, several nighttime awakenings, and waking earlier than planned with inability to fall asleep again. Women were considered to have a sleep disturbance if the disturbance occurred 3 times a week. Nonparametric locally weighted scatterplot smoothing (LOESS) regression was conducted separately for BCS and CFW and each outcome to determine the trajectory shape over time with respect to years before/after diagnosis. Results: Compared to CFW, a higher percentage of BCS reported trouble falling asleep from pre-diagnosis onwards, with a slight decline in the first 2 years post-diagnosis followed by an increase. The percentage of BCS reporting multiple nighttime awakenings increased in the first 2 years post-diagnosis, but subsequent prevalence decreased back to similar levels as the CFW. The percentage of BCS reporting waking up earlier than planned increased in the 2 years post-diagnosis and then levelled off at a consistently higher prevalence than CFW. Conclusions: BCS experience increased sleep disturbances, some of which may begin prior to diagnosis. They continue to experience greater trouble falling asleep and waking up early even five-years post-diagnosis compared to CFW. BCS should be regularly assessed for sleep disturbances and might benefit from treatments such as cognitive- behavioral therapy for insomnia. Future analyses will formally compare these trajectories, both pre- and post-diagnosis, for BCS and CFW, with covariates included. Support by NIH R01CA199137; R25CA1
Keywords: longitudinal; breast cancer; sleep