The course of depressive symptoms and mortality in older patients with cancer.

Objective: The Geriatric Depression Scale (GDS-15), a self-report questionnaire, emphasizes the psychological dimension of depression. We aimed to investigate whether GDS-15 scores were associated with mortality in older patients with cancer and describe the course of individual symptoms on the GDS-15.

Methods: An observational, multicenter, prospective study of 288 patients 70 years or older with cancer followed over 24 months. The patients were assessed with the GDS-15 at inclusion, and after four and 12 months. An extended Cox regression model assessed the association between time-dependent GDS-15 scores and mortality.

Results: After adjusting for cancer-related prognostic factors, a one-point increase in GDS-15 sum score increased risk of death by 12%. GDS-15 mean score increased during the first four months of the study, as did odds for the presence of the GDS-15 symptoms 'feel you have more problems with memory than most', 'not feel full of energy', and 'think that most people are better off than you'. The most prevalent and persistent GDS-15 symptom was 'prefer to stay at home, rather than going out and doing new things', and 'not to be in good spirits most of the time' was the least prevalent.

Conclusions: More severe depressive symptoms, as measured by the GDS-15, were associated with higher mortality in older patients with cancer. The importance of emotional distress and how to alleviate it should be investigated further in these patients.