Tuesday November 18 2008
Counselling can “double a woman’s chances of surviving breast cancer” according to the Daily Mail today. The newspaper claimed that regular sessions with psychologists also cut the chances of the cancer returning, and affected the length of time it took for the disease to reoccur.
This story comes from a study of 227 women who had surgery for breast cancer. Along with normal care, half of these women also received group counselling sessions with a psychologist every two weeks. These sessions targeted various issues including stress, lifestyle, and adherence to cancer treatment .
After an average of 11 years participants were followed-up and their survival rates were calculated. Although the study found that the rate at which women died was halved in the counselling group, the way survival rates are calculated means is not the same as the proportion of women who survived being doubled, as the newspaper reports might suggest. However, it does mean that women from the intervention group survived longer on average than those in the control group.
The study highlights the importance of appropriate support for women with breast cancer.
Where did the story come from?
Dr Barbara Andersen and colleagues from Ohio State University conducted this research. It was published in the peer-reviewed medical journal, Cancer.
The study was funded by the National Institute of Mental Health, National Cancer Institute, American Cancer Society, Longaberger Company-American Cancer Society, US Army Medical Research Acquisition Activity, Ohio State University Comprehensive Cancer Center, and the Walther Cancer Institute.
What kind of scientific study was this?
This was a randomised controlled trial looking at the effects of psychological intervention on survival in women with breast cancer.
The researchers enrolled 227 women aged between 20 and 85 years who had undergone surgery for breast cancer which did not appear to have spread. Women who had certain mental health or medical diagnoses were not eligible to participate.
Participants were interviewed at the start of the study to assess their psychological well being, health and health-related behaviours. After this, women were randomly assigned into two groups. One group received a psychological intervention, while the other ‘control’ group did not.
The way in which the women were randomised aimed to balance characteristics that might affect survival, such as the size of their tumours and whether the cancer had spread to their lymph nodes.
Psychologists provided the psychological intervention, which consisted of four months of weekly group sessions (8-12 women per session), followed by monthly sessions for eight months. The sessions aimed to reduce distress, improve quality of life and mood, improve heath related behaviours and to improve the women’s adherence to their cancer treatment and follow-up programme.
Researchers reassessed all the women’s psychological well being, health and health-related behaviours at four and 12 months into the study, then every six months up to year five, and annually thereafter.
Researchers also asked the women to report any use of antidepressants or anti-anxiety medications, or counselling outside of the intervention. There were no differences between the groups in these factors.
All women had physical examinations every three months for two years and every six months after this. They also had mammograms annually. Any signs or symptoms that suggested a possible recurrence of breast cancer were investigated with laboratory tests, radiologic studies, and biopsies as appropriate.
The researchers recorded any recurrence of breast cancer (either within the breast or in another area), and any deaths from breast cancer or any other cause among participants during follow-up.
They then compared these outcomes (recurrence, death from breast cancer, or death from any cause) in women who received the psychological intervention with outcomes in those who did not receive the intervention.
The researchers adjusted for factors that might affect the outcomes in their analyses, including factors that indicate disease prognosis (such as tumour size), and type of cancer treatment received. They also adjusted for factors that were found to differ between the groups at the start of the study, which were the participant’s “performance status” (a measure of how well they are functioning), and their level of negative mood.
What were the results of the study?
The researchers followed the women for an average (median) of 11 years. In this period about a third of the women experienced a recurrence of their cancer. This broke down into 29 women in the group receiving the psychological intervention and 33 women in the control group that did not receive the intervention.
The researchers also found that;
- On average, recurrences in the intervention group took about 2.8 years to occur (median time to recurrence), compared to 2.2 years in the control group.
- A total of 44 women died from breast cancer during follow-up, 19 women in the psychological intervention group (17%) and 25 women in the control group (22%).
- Among the women who died of breast cancer, the average survival was 6.1 years for those in the intervention group and 4.8 years in the control group.
- The total number of deaths (regardless of cause) was 57. This broke down into 24 women in the psychological intervention group (21%) and 33 women in the control group (27%).
- Average overall survival was 6 years in the psychological intervention group and 5 years in the control group.
When researchers compared the rate at which recurrences, deaths from breast cancer, and deaths from any cause occurred, they found that the psychological intervention roughly halved the rate of occurrence of these outcomes.
What interpretations did the researchers draw from these results?
The researchers concluded that their psychological intervention could increase survival.
What does the NHS Knowledge Service make of this study?
There are a number of points to consider when interpreting this study:
- The measure used to assess death looked at the rate at which women died, and it should not be interpreted as meaning that the proportion of women who died in the intervention group was halved. This can be seen by the fact that 21% in the intervention group died compared with 27% in the control group. The same applies to the rate of recurrence and death from breast cancer.
- The psychological intervention used a number of techniques, and included components aimed at improving health behaviours and adherence to treatment, as well as reducing stress. It is not possible to tell exactly which components might be having an effect, or whether the combination of components is needed to have an effect.
- The study was relatively small, so replication of these findings in a larger study will be necessary to increase confidence in these results.
- The proportion of women over 69 years of age enrolled in the control group was double that in the intervention group (8% versus 4%). Although the analysis was designed to adjust for this difference, the fact that women in the control group were older to begin with could have biased results in favour of the psychological intervention.
- The study was in women with cancer that appeared to be confined to their breast and the local area and had not spread. Therefore their results may not be representative of what would be seen in women with more advanced breast cancer.
The study indicates that interventions using several components to target psychological wellbeing, lifestyle and adherence to treatment might be capable of improving survival in women with breast cancer. The findings highlight the importance of appropriate support for women with breast cancer.
Sir Muir Gray adds...
This is very interesting, and very important.