HONOLULU – Women whose depression improved during a 1-year treatment trial for metastatic breast cancer survived a median 2 years longer than women whose depression worsened, according to a long-term follow-up study.
"Our main finding is that the course of depression over the initial year of the study can be used to predict survival up to 14 years later," Dr. David Spiegel said at the annual meeting of the American Psychiatric Association.
Therefore, screen patients with breast cancer for depression. Also, do not dismiss depressive symptoms as merely a normal component of a cancer diagnosis or treatment, he said. Another clinical implication is that psychotherapy intervention can make a significant positive difference. "There are ways of facing and living with this disease that may help patients to live longer as well as better.
"This is a tremendous opportunity for psychiatry to be a part of the mission that is now mandated at cancer centers – to help cancer patients live better with their illness," said Dr. Spiegel, director of the center on stress and health at Stanford (Calif.) University.
One-quarter of cancer patients meet the criteria for depression, Dr. Spiegel said. "The more serious your medical illness, the more likely you are to be depressed. It’s 3% of the general population, 6% of outpatients, and 12% of medical inpatients – 1 out of 9 is depressed. But we often overlook the diagnosis; we misattribute the sadness to the prognosis of the disease; the disinterest in eating to the side effects of chemotherapy; the sleep disturbance to the worry about the illness.
"All of these can be signs of depression," he said.
Therefore, more awareness of an association between depression and a cancer prognosis is warranted. "Somehow people get the idea that if you have depression, it can worsen your prognosis with heart disease. But they have a much more difficult time understanding that ... depression is just as lethal a comorbid factor with cancer," Dr. Spiegel said.
Dr. David Spiegel
He and his associates found median survival was 53.6 months for women whose baseline scores on the Center for Epidemiologic Studies–Depression Scale (CES-D) decreased over a period of 12 months, compared with a median 25.1-month survival for women whose CES-D scores increased. This 28.5-month difference in median survival was statistically significant.
The cohort included 101 women of 125 randomized to supportive-expressive group therapy or a control group with education materials who completed the CES-D scale at baseline and at three assessment points during the year (J. Clin. Oncol. 2011;29:413-20).
Only improvement in depression ratings, not treatment vs. no treatment, was associated with longer survival in this secondary analysis of the original study (Cancer 2007;110:1130-8).
Depression was an independent, long-term predictor of mortality. The researchers controlled for all the usual prognostic variables, including estrogen receptor and progesterone receptor status, disease-free interval, and age at diagnosis.
There is other evidence that psychotherapy can significantly reduce depressive symptoms in patients with advanced cancer, said Dr. Spiegel. For example, a Cochrane database analysis showed such a benefit in patients with incurable cancer who received supportive psychotherapy, cognitive-behavioral therapy, or problem-solving psychotherapy (Cochrane Database Syst. Rev. 2008;CD005537).
Dr. Spiegel said the psychotherapy in his study reduced patients’ tendency to suppress emotion. "So this outcome is not about distress; it’s about their management of distress. This, it turned out, mediated the reduction in depression and anxiety.
"We encourage people to face their fears of dying and death. We call it ‘detoxifying dying,’ " Dr. Spiegel said. Patients learn to face death, to reorder priorities, and to communicate better with families and physicians.
More support for an association between less depression and better outcomes for cancer patients emerged from a study of 107 patients with metastatic non–small cell lung cancer (N. Engl. J. Med. 2010:363:733-42). Fewer patients who received early palliative therapy reported depressive symptoms, 16%, vs. 38% of patients assigned to standard care. In addition, the early palliative care group had a longer median survival (11.6 months vs. 8.9 months). Both differences were statistically significant.
However, there is still no consensus in the literature about psychosocial intervention and cancer survival. Seven randomized trials now show a survival benefit, and six show no difference, Dr. Spiegel said. "The results are not random; I’m glad to say that no studies show that psychotherapy kills patients."
Although further research is warranted, Dr. Spiegel said, "it is now reasonable to raise the possibility that treating depression and other psychiatric aspects of cancer may not only help people live better, but may help them live longer."