Women who receive hormonal therapy for breast cancer are at increased risk of developing chronic conditions later in life, according to new research published in the Medical Journal of Australia.
Researchers from Flinders University and the University of South Australia found that rates of depression, osteoporosis, diabetes, cardiovascular conditions, chronic pain and gastric disorders were higher among breast cancer survivors who had received hormonal cancer treatment than among those without breast cancer.
Hormonal therapy, also known as endocrine therapy, is currently used to reduce the risk of cancer recurrence for 70% of breast cancers in Australia.
It is typically administered after surgery or a course of chemotherapy, and/or radiation.
“Knowing that hormonal therapy may predispose women to developing chronic illnesses gives us the chance to develop effective, long-term models of care for these patients,” says Flinders University Professor and co-researcher of the study, Bogda Koczwara.
“Developing the strategies and tools to manage co-existing chronic conditions after breast cancer should now be an essential part of every patient’s overall treatment plan.”
The study compared the health of two groups of women over a ten-year period, the first group comprising women who were receiving hormonal therapy for breast cancer and the second group comprising women of a similar age who did not have breast cancer.
The emergence of chronic disease and the frequency with which it developed was mapped in both groups.
“Our study clearly found that chronic illnesses developed more frequently in women with breast cancer than in those without breast cancer,” Professor Koczwara says.
“We also found that the risk for developing chronic illnesses among women with breast cancer was greatest during their first year of hormonal therapy.
“Some of this risk may be attributable to hormonal therapy, and some of it may be the effect of the cancer itself or its earlier treatment.
“Hormonal therapy is still a very important treatment option for women with hormone responsive cancer, but we need to manage its subsequent impact on long-term health in a more informed and impactful way,” says Professor Koczwara.
The study was the first of its kind in Australia to comprehensively examine the relationship between breast cancer treatment and the development of successive chronic disease using the analysis of prescribing patterns.
“The good news is that most women diagnosed with breast cancer in Australia can be cured and we now have a way of using routine data to monitor the risk of chronic disease after cancer,” Professor Koczwara says.
“The next step is to prevent these conditions from developing through healthy lifestyle habits, exercise, diet and other strategies.”
Professor Koczwara is supported by the National Breast Cancer Foundation and is located at the Flinders Centre for Innovation in Cancer.
Her co-researchers on this study include Huah Shin Ng, David Roder, Theo Niyonsenga and Agnes Vitry from the University of South Australia.
The full findings of the study can now be read in the published paper: Ng HS, Koczwara B, Roder DM, Niyonsenga T and Vitry AI. ‘Comorbidities in Australian women with hormone-dependent breast cancer: a population-based analysis’, Medical Journal of Australia, 15 January 2018, vol. 208, no. 1, pp 24-28, doi: 10.5694/mja17.00006.