Sleep macro- and microstructure in breast cancer survivors

Abstract

Complaints of sleep disturbance are prevalent among breast cancer (BC) patients and are predictors of quality of life. Still, electrophysiological measures of sleep are missing in patients, which prevents from understanding the pathophysiological consequences of cancer and its past treatments. Using polysomnography, sleep can be investigated in terms of macro- (e.g. awakenings, sleep stages) and micro- (i.e. cortical activity) structure. We aimed to characterize sleep complaints, and macro- and microstructure in 33 BC survivors untreated by chemotherapy and that had finished radiotherapy since at least 6 months (i.e. out of the acute effects of radiotherapy) compared to 21 healthy controls (HC). Compared to HC, BC patients had a larger number of awakenings (p = 0.008); and lower Delta power (p < 0.001), related to sleep deepening and homeostasis; greater both Alpha (p = 0.002) and Beta power (p < 0.001), related to arousal during deep sleep; and lower Theta power (p = 0.004), related to emotion regulation during dream sleep. Here we show that patients have increased cortical activity related to arousal and lower activity related to sleep homeostasis compared to controls. These results give additional insights in sleep pathophysiology of BC survivors and suggest sleep homeostasis disruption in non-advanced stages of BC.

Demoralization and Its Association with Quality of Life, Sleep Quality, Spiritual Interests, and Suicide Risk in Breast Cancer Inpatients: A Cross-Sectional Study

“…However, the negative associations with breast cancer remain unclear. Patients with breast cancer may suffer from REM or NREM sleep problems [25,26]. A previous study revealed that demoralization mediates the effect of stress on sleep disturbances in patients with breast cancer [18].…”

Mediating roles of activities of daily living and depression on the relationship between sleep quality and health-related quality of life

“…This indicates that sleep quality is a more distal factor influencing HRQOL, with sleep behavior related to personal plans and awareness, while depression and disability were more direct factors affecting HRQOL. The sleep disturbance model suggests that sleep disorders adversely affect physical health by weakening emotional regulation and disrupting the body’s circadian rhythm 45 . Hence, the impact of sleep quality on HRQOL is primarily mediated through an indirect pathway.…”

Effects of sleep disturbances and circadian rhythms modifications on cognition in breast cancer women before and after adjuvant chemotherapy: the ICANSLEEP-1 protocol

“…Although sleep disturbances are thought to be a side effect of cancer treatment, notably chemotherapy [ 13 , 83 ], multiple studies showed that sleep complaints in BC exist even in BC patients who did not receive chemotherapy [ 84 , 85 ] and their presence has detrimental effects on patients’ quality of life [ 86 ]. Sleep is intrinsically linked to circadian rhythms and a recent review highlighted the presence of circadian disruptions in BC, more specifically of cortisol and rest-activity rhythms [ 13 ].…”