Depression Care for People with Cancer program is highly effective in improving depression and quality of life (QoL) in depressed patients with cancer, but there is no evidence for a significant effect on survival according to long-term data on deaths of all causes in the SMaRT Oncology-2 and 3 trials. The investigators led by Professor Michael Sharpe of the Psychological Medicine Research, University of Oxford Department of Psychiatry, Warneford Hospital, Oxford, UK, published their results in Lancet Psychiatry on March 12, 2018.

In a linked comment, Alex Mitchell of the University Hospitals of Leicester, University of Leicester, Leicester, UK explained that patients with depression have a higher incidence of specific cancers and have a worse prognosis in observational studies in comparison to cancer patients without depression.

Depression as comorbidity has been associated with worse survival in cancer patients. However, it was not known if treating depression improves survival. In the SMaRT Oncology-2 trial among patients with good prognosis cancers and SMaRT Oncology-3 trial among patients with lung cancer, the study team previously found that a depression treatment program was effective in reducing comorbid major depression. In the latest analysis, they aimed to identify whether their treatment program also had an effect on survival.

Both trials were conducted in three cancer centers and their associated clinics in Scotland. The cancer patients with major depression in outpatient setting were randomly assigned in a 1:1 ratio to Depression Care for People with Cancer program or usual care, with stratification and minimization by age, primary cancer, and sex. The study team obtained long-term data on deaths of all causes censored at July 31, 2015, and analyzed survival as a trial outcome. They estimated unadjusted hazard ratios (HRs) for each trial using Cox regression, and pooled the log HRs in a fixed-effects meta-analysis.

In total, 642 participants were recruited: 500 patients in the SMaRT Oncology-2 trial and 142 patients in the SMaRT Oncology-3 trial. The study patients were followed up for a median of 5 years and 1 year, respectively. Within the study period, 27% of SMaRT Oncology-2 patients and 80% of SMaRT Oncology-3 patients died.

The investigators found no significant effect of Depression Care for People with Cancer program on survival in the total follow-up period for either SMaRT Oncology-2 (HR 1.02, p = 0.93) or SMaRT Oncology-3 (HR 0.82, p = 0.28). Pooled HR was 0.92 (p = 0.51).

The authors concluded that despite the absence of an effect on survival, the management of depression remains important for its beneficial effect on QoL.