In a study of nearly 400 breast cancer survivors who had been disease-free for an average of nine years, 42 percent cited stress as one of the main causes of their breast cancer. This was many more than the 27 percent of the women who felt genetics was involved, the 26 percent who attributed a role to environmental factors, 24 percent who blamed hormones and 16 percent who thought diet was a contributing factor; the scientific evidence supporting these factors as potential causes of breast cancer is far stronger than that for stress.
Sixty percent of the women also felt that a positive attitude helped them keep the breast cancer from returning, followed by diet (50 percent), healthy lifestyle (40 percent), exercise (40 percent), stress reduction (28 percent), prayer (26 percent), complementary therapies (11 percent), luck (4 percent) and tamoxifen (4 percent).
The conviction that stress caused cancer or that a positive attitude has kept their breast cancer from recurring may give women a sense of control over the disease, say Donna E. Stewart, MD, and her associates at University Health Network and the University of Toronto. This belief can be beneficial when it helps women switch to a low-fat diet or exercise more, but can backfire in a feeling of "personal failure" if the disease returns.
The study will be published in the March issue of Psycho-Oncology.
They found that the women who believed their cancer was caused by stress were more likely to use complementary therapies and anti-depressants and were less likely to smoke, suggesting that women's beliefs about their disease may be "associated with specific health behaviors used to combat the illness," the researchers say.
They mailed questionnaires to 500 women who had been disease-free for at least 2 years. The questionnaires were returned by 378 of the women. Of those, 322 answered the question on what they thought caused their disease, and 330 answered the question on what kept it from returning.
The questionnaire also asked the women what advice they would give another woman who was recently diagnosed with breast cancer. More than half (52 percent), said they would tell the woman to have hope, have courage and be positive. And 58 percent said they would take more control of their treatment if they had to relive the experience.
The researchers recommend that health care professionals talk to women about their beliefs. The patient's "views may assist in understanding how she perceives her condition, in encouraging lifestyle changes, and in framing disease management in meaningful ways that give a greater sense of personal control," said Stewart, who is professor and chair of women's health.
