This study examined the association between perceived stress, loneliness and sleep disorders respectively, as well as explored whether resilience (a protective factor) could moderate the relationship between perceived stress, loneliness and sleep disorders among Chinese female BC patients. In our study, the prevalence of sleep disorders in female BC patients was 36.58% and it was much higher than the prevalence of general population in China (14.39%) [24], higher than the prevalence in Korea (16.61%) [22], higher than the prevalence of a previous study among adult female BC patients in Australia (17.5%) [40] and also higher than the prevalence in America (18.64%) [8]. There might be several reasons for the situation. First of all, the negative psychological emotions or concomitant symptoms associated with the disease have not been eased. Specifically, psychological stress and discomfort following surgery contributed to sleep disturbances in BC patients [23]. In addition, lacking of professional psychological nursing staff and counseling institutions to disseminate knowledge to patients about how to alleviate cancer-related adverse symptoms like sleep disorders. Consequently, the problem of sleep quality among BC patients are worthy of concern as well as need to get resolved in time.
The results also revealed that perceived stress and loneliness were significantly correlated with sleep disorders. Women diagnosed with BC would give rise to a series of stressors, including fear of disease progression, unexpected side effects and psychologically unpleasant emotional experience [31]. Psychological stress could have a profound impact on sleep, such as causing insomnia or dyssomnia [29]. Indeed, sleep disorders were more commonly when patients with stronger and frequent stress response [28]. Hence, healthcare providers should target for various forms of stress reduction interventions which can relieve sleep disorders for female BC patients. Furthermore, loneliness was also associated with sleep disorders. Cancer-related loneliness is mostly attributed to unmet social involvement or expectations in personal interactions [1]. Loneliness prompted the perception of social threats, which might result in poor health outcomes and stronger sense of stress as well as heighten adverse symptoms such as fatigue, sleep disturbances [2]. Scholars have demonstrated loneliness leads to increasing daytime dysfunction and nightly micro-awakenings, thus indicating the linkage of loneliness with sleep disorders [27]. Overall, interventions related to loneliness should be given more attention to mitigating negative impact on BC patients.
In this study, resilience was a positive and protective psychology resource for sleep disorders. Additionally, resilience was found to moderate the association of perceived stress and loneliness with sleep disorders. When taking the interaction of perceived stress, loneliness and resilience respectively into the model, it was obvious that the interaction had a significant effect on sleep disorders. Simple slope analysis also revealed that when resilience was higher, the association between perceived stress, loneliness and sleep disorders becomes weaker separately. That is, the results suggested that when women experience a traumatic event and have lower level of resilience, perceived stress aggravated their sleep disorders. Inversely, individuals with higher resilience serves themselves as tenacious and are adaptable to challenging events, which help them with their sleep problems [9]. Similarly, the loneliness-sleep disorders relationship was much stronger for those with lower resilience in comparison to those with high levels of resilience. Hence, interactions indicated that the sensitivity among female breast cancer patients to the effects of perceived stress and loneliness on sleep disorders depends on the positive psychological factor of resilience. The results are in line with previous studies, which found in the COVID-19 context of loneliness-sleep problems [14] and the result of the study on gastrointestinal cancer patients [38], that both perceived stress or loneliness and resilience predict sleep disorders by an interactive manner.
Limitations
Three limitations of our study should be noted. First, conclusions on the causality of the linkages observed among perceived stress, loneliness, resilience and sleep quality could not be drawn as a result of the cross-sectional design. Second, patients were recruited from a single hospital, Liaoning Province, northeast China, it still needs further studies to be carried out to examine the external generalization of our results among breast cancer patients in different regions or cultural backgrounds. Third, all the variables were measured by using self-report questionnaires, which could be vulnerable to retrospective bias. Further research should consider multiple methodologies to assessing sleep quality.
Clinical implications
Results of our study have implications for future research and clinical nursing. Firstly, clinical nurses should pay attention to the impact that intrinsic psychological symptoms have on sleep quality after diagnosis of BC in order to alleviate sleep disturbances in this population. For this purpose, consultation by psychologists and mental health professionals should be offered to the patients with poor sleep quality. Secondly, social-psychological factors (perceived stress and loneliness) ought to be considered as one of the most dominating prevention indicator for cancer patients, which may be a key missing component in nursing process [2, 37]. More concretely, the psychological demand regarding the course of the patients’ treatment and care should be combined with to relieve their negative emotion and improve sleep quality. Finally, future research needs to be tailored to some positive psychological variables (e.g., resilience) in the development of improving cancer patients’ health interventions.