Team highlights long-term impact of socioeconomic inequalities on quality of life for women after breast cancer

When it comes to health, inequalities can be seen at every level for women with breast cancer: prevention, screening, diagnosis, treatment, and survival. But what about their quality of life?

A team from the University of Geneva (UNIGE), the University Hospitals of Geneva (HUG), Inserm, and Gustave Roussy has tracked nearly 6,000 women diagnosed with breast cancer over a 2-year period, showing that socioeconomic status has a major and lasting impact on their quality of life, despite identical medical treatment. These results from the CANTO study, published in the Journal of Clinical Oncology, call for socioeconomic factors to be taken into greater account in support programs for women with breast cancer.

Social and economic determinants (such as income and educational levels) impact how individuals cope with illness and are one of the main causes of inequalities in health. In cancer care, socioeconomic inequalities are present throughout the continuum of care, from prevention to diagnosis, treatment, and survival.

"However, the extent of socioeconomic inequalities in the quality of life of women diagnosed with breast cancer and how these change during treatment was not known," explains José Sandoval, an oncologist at the HUG Department of Oncology and a researcher in the Departments of Medicine and Community Health and Medicine at the UNIGE Faculty of Medicine, first author of this study. "We sought to quantify the inequalities in quality of life for these women, both at the time of diagnosis and in the following two years."

Nearly 6,000 women monitored over two years

The 5,900 women who took part in this study were treated in France for early breast cancer, a common form of cancer from which more than 80% of women recover.

"Many of the women received heavy treatment in the first year following their diagnosis—including surgery followed by chemotherapy— followed by endocrine therapy in the second year. We followed them over two years to capture changes in quality of life over the medium term," explains Gwenn Menvielle, research director at Inserm and at Gustave Roussy, who led this research.

The research team examined areas of quality of life—general tiredness, psychological state, sexual health, and side effects—according to a number of socioeconomic indicators: level of education, household income, and perceived financial situation. Combining these elements produces a score where 0 indicates no inequalities.

Inequalities are increasing rapidly

At diagnosis, the inequalities in quality of life between the two socioeconomic extremes are notable, with a score of 6,7. The score increases to 11 during treatment, then remains at 10 two years after diagnosis, a higher score than at that time.

"If we expected a certain degree of inequality at the start of the disease, the fact that these inequalities increase rapidly and persist for so long is a surprise," mentions José Sandoval. "The impact on quality of life is much more pronounced for women with fewer resources, irrespective of the biological characteristics of their cancer, their age or the treatment they have received."

Why? The answers are to be found not in the treatment, which is similar for all women, but probably in all the elements of support around medical management.

"Having the time, money, and access to information to take care of oneself, find support resources, and better manage the physical and psychological side-effects of the disease will probably be easier for women of high socioeconomic status than for, say, a single mother on a low income with no carer for her children," points out José Sandoval. "These factors influence the disease and its consequences on patients' physical and psychological health."

Taking better account of inequalities

Equal access to health care is not synonymous with the absence of inequality. The socioeconomic context can have a major impact on health status in the same way as biological characteristics.

"When we talk about precision oncology, we need to consider the whole person, including their social dimension," add the authors. "Our data concerns women treated in France, a country with equal health care access. In countries without a universal health care system, these inequalities are likely to be even more pronounced."