Mediating Effect of Emotional Distress Between Sleep and Life Quality in Women Undergoing Cancer Screening

Monday, 23 July 2018: 10:20 AM

Ya-Jung Wang, PhD, RN
Chih-Jung Wu, MS, RN
School of Nursing, National Yang-Ming University, Taipei, Taiwan


Breast cancer is the leading cause of female cancer in Taiwan. Due to the advance in medical technology, national policy of early detection and treatment, the overall five-year survival rate is longer than the past. However, women with breast cancer still suffer from lots of physical and emotional problems from screening to treatment. Evidence indicates that emotional distress is associated with sleep quality and quality of life. Moreover, most studies focus on emotional problems among patients with abnormal screening reports or with breast cancer diagnoses. Few studies focused on cancer screening population.The purpose of this study was to explore the mediation effect of emotional distress between sleep quality and quality of life in women undergoing breast cancer screening.


This research used a cross-sectional design. Data was collected from an outpatient department and mammography rooms in a medical center in central Taiwan. The main research variables included emotional distress, sleep quality and quality of life. In addition, SPSS 21.0 software was used for data analysis. Research instruments included demographic information sheet, Hospital Anxiety and Depression Scale (HADS), Pittsburgh Sleep Quality Index(PSQI) and Functional Assessment of Cancer Therapy Scale –General(FACT-G). The statistical methods included descriptive statistics (mean, standard deviation [SD], frequency, and percentage) and inferential analyses (Pearson’s correlation coefficient and hierarchical regression).


A total of 158 participants were included in this study with an average age ± SD of 53.94±6.39 years. Significant correlations were found between the main variables. To be more specific, both emotional distress (r=-0.754, p<0.001) and sleep quality (r=-0.409, p<0.001) were negatively correlated with quality of life and a positive correlation was between sleep quality and emotional distress (r=0.454, p<0.001). The mediator model showed that both emotional distress (β=-0.704, P<0.001)and sleep quality (β=-0.409, P<0.001) significantly predicted quality of life. Likewise, sleep quality also significantly predicted emotional distress(β=0.454, P<0.001). However, after adding emotional distress as a mediator, sleep quality no longer significantly predicted quality of life(β=-0.09, P=0.146). According to the above-mentioned model, emotional distress is a mediator between sleep quality and quality of life.


Results of this study can be used as the basis for further research focusing on cancer screening. Emotional distress is a mediator to the effect of sleep quality on quality of life in women undergoing breast cancer screening at the outpatient department. In the future, mental health assessment tools and education on examination and disease are suggested during the screening process to reduce emotional distress and improve quality of life in women who have unhealthy sleep quality during breast cancer screening.