Interrelationship of depression, stress and inflammation in cancer patients: a preliminary study.

OBJECTIVE: Depression is common in cancer patients and detrimentally affects patients' quality of life. Both depression and stress are associated with raised inflammatory marker levels. This prospective study of cancer patients focuses on childhood trauma, recent life events and inflammatory marker levels as risk factors for high post-surgery depressive symptoms.
METHODS: Ninety cancer patients (56 head and neck, 34 colorectal) completed the Hospital Anxiety and Depression Scale, pre-surgery and six, 12 and 24 weeks post-surgery. Recent life events and childhood trauma were assessed at six and 12 weeks respectively. Blood samples were taken pre- and one and six weeks post-surgery to measure C-reactive protein (CRP) and pro-inflammatory cytokine levels.
RESULTS: Childhood trauma and recent life events were risk factors for higher depressive symptom levels. In colorectal cancer patients, baseline CRP levels were associated with depressive symptom levels at six (p=0.008) and 12 weeks (p=0.038). Baseline and six week Tumour Necrosis Factor-alpha (TNFα) levels were significantly associated with higher depressive symptoms at later time points after adjusting for cancer-related variables. Childhood trauma was positively associated with TNFα and CRP levels in colorectal cancer patients. The associations between inflammatory markers and depressive symptoms were not significant after adjusting for childhood trauma. LIMITATIONS: Small sample size.
CONCLUSIONS: Raised inflammatory mediator levels may be risk factors for depressive symptoms in colorectal cancer patients and thus worth considering as a potential therapeutic target. These pilot data support recent findings demonstrating long-term effects of childhood adversity on adult health.