The mediating effect of activity restriction on the relationship between perceived physical symptoms and depression in cancer survivors.

Purpose: Several studies have explored factors causing depression in cancer survivors, including perceived physical symptoms. Another critical factor in the depression symptomatology of cancer survivors is activity restriction (AR). We investigated how AR mediate the effects of perceived pain and fatigue on depression in cancer survivors.
Methods: Cancer survivors (n = 61; mean age 56.16 years) that were recruited through cancer support groups in Japan participated in this study. Participants completed a battery of questionnaires comprising demographic and clinical information, the Pain Catastrophizing Scale, the Cancer Fatigue Scale, the Activity Restriction Scale for Cancer Patients, and the Hospital Anxiety and Depression Scale.
Results: Mediation analysis indicated that AR partially mediates the effect of pain on depression. Direct paths from pain to AR, AR to depression, and pain to depression were significant (P < .005). Moreover, indirect paths from pain to AR, AR to depression, and pain to depression were also significant at the 95% level [0.04-0.13]. However, AR did not mediate the effect of fatigue on depression, and fatigue had a significant direct path to both AR and depression (P < .005).
Conclusion: This study aimed to explore the mediating effect of AR in the relationships of perceived pain and fatigue and depression in cancer survivors. We found that AR mediates perceived pain to depression, however not for perceived fatigue. In addition, because AR was experienced in the face of any survivorship period, AR may need to be treated as a long-term effect of the cancer diagnosis.
(© 2019 The Authors. Psycho-Oncology published by John Wiley & Sons Ltd.)