25 February 2020
New study findings suggest that weight gain after breast cancer is a greater problem than previously thought. The first national survey on weight after breast cancer in Australia, published in BMC Cancer (opens in a new window) journal, found close to two-thirds (63.7%) of women reported weight gain at an average of nine kilograms after a breast cancer diagnosis, and overall nearly one-in-five women (17%) added more than 20 kilograms.
Researchers from NICM Health Research Institute, Western Sydney University and ICON Cancer Centre, Sydney Adventist Hospital, Wahroonga, surveyed 309 women with breast cancer living in Australia using an anonymous, self-administered online cross-sectional survey between November 2017 and January 2018. The national sample consisted mainly of members from Breast Cancer Network Australia (BCNA).
The majority of women surveyed (77%) reported gaining weight within the first 12-18 months after diagnosis, which could be the ideal 'window of opportunity' to provide additional support for weight management among women with breast cancer says Dr Ee, lead author, general practitioner and senior research fellow at NICM Health Research Institute, Western Sydney University.
“As well as significant weight gain, we also found high levels of concern about weight among our survey participants. Timing may be the key in helping women to manage weight after a diagnosis of breast cancer,” said Dr Ee.
"Cancer services and general practitioners play an important role in having early conversations with women, and referring them to a team of qualified healthcare professionals such as dieticians and exercise physiologists with experience in cancer,” she said
The survey also found:
- The proportion of women who were overweight or obese increased from 48% at time of diagnosis to 67% at the time of the survey, with the proportion of women who were obese almost doubling from 17% to 32%.
- The majority (69%) of women gained weight in excess of the rates reported in age-matched controls without breast cancer – an additional 2.42 kilograms over five years.
Professor John Boyages AM, co-author and radiation oncologist at Icon Cancer Centre says that all women should be prescribed exercise after being diagnosed with breast cancer, according to the Clinical Oncology Society of Australia (COSA) guidelines.(opens in a new window)
“As doctors we really need to actively think about weight, nutrition and exercise and advise about possible interventions,” said Professor Boyages.
“Breast cancer is the most common cancer in women worldwide and in Australia, and weight gain is common after breast cancer treatment. Many patients assume they will lose weight. Weight gain adds to self-esteem problems, increases the risk of heart disease and other cancers and several reports suggest it may affect prognosis and also increases the risk of arm swelling (lymphoedema). Prescribing a healthy lifestyle is just as important as prescribing tablets.”
Dr Ee further says that after diagnosis of breast cancer, many women experience fatigue, which can be a barrier to staying active, and studies show exercise is an effective treatment for fatigue. However, for this to be feasible and sustainable, she says supervision by an experienced exercise physiologist is invaluable.
BCNA CEO Kirsten Pilatti says many studies highlight the importance of specialists such as exercise physiologists and nutritionists for breast cancer treatment plans, however they are often an unfunded component of follow-up care.
“For many breast cancer survivors, the cost of accessing the expertise of these specialists puts them beyond their reach. We want a system that helps women and men diagnosed with breast cancer to come out and be able to move on with their life, not be crushed by the experience,” said Ms Pilatti.
The researchers will next analyse the survey data to investigate reasons why women are gaining weight after breast cancer, with several risk factors reported in other studies, including the type of treatment that women receive, and whether or not they were menopausal before diagnosis and treatment.
The paper, Weight before and after a diagnosis of breast cancer or ductal carcinoma in situ: a national Australian survey, is available online (https://doi.org/10.1186/s12885-020-6566-4) (opens in a new window) in the Journal BMC Cancer.
- Breast cancer is the most common cancer in women worldwide and in Australia.
- There were over 2 million new cases of breast cancer (BC) globally in 2018, with this figure expected to rise to over 3 million by 2040, by which time Australia expects to diagnose more than 25,000 new cases annually.
- Obesity is a known risk factor for BC, particularly for postmenopausal women. Obesity at diagnosis is associated with worse BC survival and all-cause mortality rates and may increase the risk of cancer recurrence by 30–40%.
- Furthermore, weight gain is common after BC diagnosis, and may increase the risk of disease recurrence and mortality and have a negative impact on quality of life.
- The study was supported by NICM Health Research Institute and Western Sydney University.
- DOI: 10.1186/s12885-020-6566-4 (opens in a new window)
- Study methods and limitations: see paper.
- Keywords: breast cancer, DCIS, overweight, obesity, weight gain, Australian women, national survey, prevalence