Dysfunctional Beliefs about Sleep in Cancer Patients Can Mediate the Effect of Fear of Progression on Insomnia

Abstract

Background and Objective The role of the dysfunctional belief about sleep is important for the development of insomnia among cancer patients. This study intended to investigate whether dysfunctional belief about sleep mediates the relationship between fear of progression and insomnia in cancer patients. Methods Three hundred and thirty-seven cancer patients participated in our study. Dysfunctional belief about sleep, severity of insomnia, depression, fear of progression, and anxiety were measured using the following questionnaires: Cancer-related Dysfunctional Beliefs about Sleep (C-DBS); Insomnia Severity Index (ISI); Patient Health Questionnaire-9 (PHQ-9); Fear of Progression (FoP); and the state subcategory of State and Trait Anxiety Inventory (STAI). Path analysis was used to clarify the relationships among the variables. Since C-DBS consists of two items, i.e., Q1-immune & Q2-recurrence, we implemented an additional path analysis including these variables separately. Results C-DBS mediated the effect of FoP (β = 0.36, p < 0.001) and patient sex (β = 0.13, p = 0.009) on ISI. PHQ-9 (β = 0.32, p < 0.001) and STAI (β = -0.09, p = 0.071) had a direct influence on ISI scores. In our second path analysis, Q1-immune item mediated the effect of FoP (β = 0.19, p < 0.001) on ISI, and Q2-recurrence item mediated the effect of FoP (β = 0.23, p < 0.001) and patient sex (β = 0.09, p = 0.019) on ISI. Conclusions Our path analysis model indicated that C-DBS mediates the effect of FoP and patient sex on ISI. Our second path analysis results suggested that there could be an internal process of Q1 and Q2 item. Efforts to reduce dysfunctional beliefs should be considered as well as management of fear of progression for better sleep of cancer patients.

Keywords

• sleep-related cognition
• insomnia
• cancer
• fear