Objectives/Purpose
Women with metastatic breast cancer (MBC) report significantly greater sleep difficulties, traumatic stress, distress, and poorer quality of life (QoL) compared to the general population which, left untreated, can lead to further health burden and shorter survival times. Despite this, research on the relationship between traumatic stress, sleep difficulties, distress, and QoL have been nearly-exclusively in non-metastatic settings. Therefore, we sought to, a) quantify the level of sleep difficulties and traumatic stress in women with MBC; b) explore how these four factors are correlated; and c) explore how the combined effect of traumatic stress and sleep difficulties impact distress and QoL.
Sample and Setting
Cross-sectional baseline data of Australian women, aged 18+ diagnosed with MBC, recruited as part of the Finding My Way-Advanced clinical trial.
Procedures
This study conducted a secondary analysis of available baseline data (n = 176) from the ongoing randomised control trial – Finding My Way-Advanced – which compares an online psychosocial program for women with MBC against a digital-resource control. Traumatic stress (PSS-SR), general distress (DASS), QoL and sleep difficulties (EORTC-QLQ-C30) were considered.
Results
Interim analyses indicated that 37% of the sample experienced severe sleep difficulties and 41.5% experienced clinically-elevated levels of traumatic stress. Traumatic stress and sleep difficulties, respectively, were independently and significantly associated with poorer distress (t(171)=13.58, p=< .001; t(171)=2.86, p=.005) and QoL outcomes (t(172)=-8.39, p=< .001; t(172)=-4.25, p=< .001). While the combined effect of traumatic stress and sleep difficulties did produce poorer outcomes for distress (R2=0.603, p <.001) and QoL (R2=0.445, p <.001), sleep difficulties did not appear to moderate the relationship between traumatic stress and distress (R2change=0.0052, p=.14) or QoL (R2change=0.011, p=.067).
Conclusions and Clinical Implications
Traumatic stress and sleep difficulties are important vulnerability factors for distress and impaired QoL that should be screened by clinicians and targeted for early intervention.