SOURCE: King's College London, news release, Nov. 30, 2015
THURSDAY, Dec. 10, 2015 (HealthDay News) -- Breast cancer patients with depression may have a much higher risk of death than those without the mental illness, a new study suggests.
"Low mood and depression are understandable reactions to a breast cancer diagnosis. Clinicians generally know to look out for this, but these findings emphasize the need to ask patients with cancer about their mood and for women to know it's OK to ask for help," Elizabeth Davies, of the division of health and social care research and cancer studies at King's College London, said in a school news release.
"It is important women feel they can talk about these feelings and do not feel guilty about difficulty coping or depression, which can be a natural response to cancer diagnosis," she added.
Although this study found a link between depression and breast cancer survival, it's important to note that the research can't prove cause-and-effect.
For the study, researchers reviewed the medical records of more than 77,000 women who were diagnosed with breast cancer between 2000 and 2009. The study followed the participants' health until the end of 2010.
More than 420 of the women had a history of depression before learning they had breast cancer. More than 530 were diagnosed with depression after their cancer diagnosis.
Women with new depression had a 45 percent higher risk of death from all causes than other patients, the study found.
The link between newly diagnosed depression and increased risk of death remained even after the researchers accounted for factors such as older age, cancer stage, other illnesses and socioeconomic status.
Women with a history of depression before their cancer diagnosis also had a higher risk of death. Five years after the cancer diagnosis, 55 percent of these women were still alive, compared with 75 percent of those never diagnosed with depression, the study showed.
Depression-associated behaviors such as a less healthy lifestyle, chronic stress and being less likely to receive or comply with treatment could account for some of the increased risk of death among patients with depression, according to the researchers.
"Greater social support or psychological interventions for women with breast cancer could help to reduce the negative effects amongst those most at risk of depression," Davies said.
The study was published recently in the journal Psycho-Oncology.
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