Background
Complementary medicine (CM) or complementary therapies refer to ‘a group of diverse medical and healthcare systems, practices and products that are not generally considered part of conventional medicine’ [
1]. In this paper, the terms “complementary medicine”, “complementary therapies” and “complementary and alternative medicine” are used synonymously. Boundaries within CM and between the CM domain and that of the dominant system are not always clearly defined or fixed [
2]. Women with breast cancer (BC) are the most likely group to use CM out of all cancer patients [
3] with CM use reportedly as high as 75% [
4]. Patients with breast cancer using CM are mostly younger and more highly educated than non-CM users in the majority of studies. Some studies have also shown that women with breast cancer using CM had higher income than those who did not [
3]. An association between CM use and more advanced breast cancer at diagnosis has also been found [
5].
Weight gain is common after a breast cancer diagnosis and may increase the risk of disease recurrence and all-cause mortality, increase the burden of chronic disease from obesity-related disorders such as cardiovascular disease and diabetes, and have a significantly negative impact on quality of life [
6]. Weight gain after a BC diagnosis is thought to be multifactorial and related to the use of systemic treatment as well as changes in lifestyle [
6,
7]. There is emerging evidence for the use of some CM to assist weight loss in the general population. However, little is known about the use of CM for weight loss amongst women with BC, making it important to understand patterns and drivers of use of CM amongst women with BC.
The aim of this national survey was to describe the use of CM for weight management after BC in Australian women.
Discussion
In our survey, we found high rates of CM use for any condition, but lower rates of use for weight management, with limited perceived effectiveness of the therapies that had been tried. Women in our survey cited barriers to use of CM for weight management after BC including lack of research for effectiveness. However, CM was seen to be advantageous in improving general wellbeing, providing relaxation, and being non-pharmacological. Three quarters of women would consider a CM if there was evidence for effectiveness (particularly, acupuncture/acupressure, relaxation techniques, yoga, supplements, and meditation).
Almost three quarters of women in our sample had used a CM in the preceding 12 months. This is consistent with evidence from a recent systematic review reporting prevalence of up to 87% in Australia [
3]. CM users in our sample cited reasons for use such as improving general physical wellbeing, reducing stress/improving psychological wellbeing and treating conditions unrelated to cancer. Similarly, in another survey, BC survivors use CMs to “help healing, to promote emotional health, and to cure cancer” [
3]. The most recent survey conducted in Australia on CM use in BC survivors reported women believed that CMs improved their wellbeing, boosted their immune system, reduced side effects of treatments, reduced symptoms of cancer, treated the cancer, and prevented recurrence [
13]. Cancer patients mostly report using CM in an adjunctive manner, e.g. to improve overall general health and wellbeing [
14] or to minimize adverse effects from conventional treatment and to prevent further illness [
15]. Collectively, these data suggest that women with BC seek a range of therapeutic options to optimize all aspects of their health and wellbeing in a holistic manner, particularly to improve psychological wellbeing.
In our sample, the most commonly used CMs for any reason were nutraceutical supplements, massage, meditation and yoga which is consistent with what is reported in the literature [
3]. Some studies specifically reported whole medical systems such as naturopathic or traditional Chinese medicine most commonly used by BC patients [
16,
17]. Of interest, although nutraceutical supplements were the most commonly used therapy, about half of women perceived their effectiveness to be neutral. The therapies with the highest perceived effectiveness included massage, acupuncture/acupressure, relaxation techniques and yoga.
A smaller proportion (31%) of women had used CM for weight management. In non-cancer populations, studies suggest that up to 70% of people with obesity use CM [
18,
19] particularly if they are female [
18]. People with metabolic syndrome are also higher users of CM [
19] compared to people without metabolic syndrome. However, it is unclear if the high use of CM in people without obesity indicates use specifically for weight management, or if CM are used for other reasons [
18,
19]. We could not find any literature describing the prevalence of use of CM for weight management in BC survivors. The therapies were mostly perceived as neutral in terms of effectiveness, with the exception of yoga and meditation, which greater than 40% of our sample thought were effective treatments.
One of the most commonly cited barriers to using CM in our study was the perceived lack of evidence for effectiveness. Similarly, in a qualitative study, the most common reason given for deciding not to use CM amongst cancer survivors was a lack of meaningful information regarding safety and efficacy [
15]. However, around three quarters of women in our sample indicated that they would try a CM to assist with weight management should there be sufficient evidence demonstrating effectiveness. The most commonly cited CM that would be chosen in this situation was acupuncture/acupressure, with around half of women willing to trial these modalities, followed by relaxation techniques, yoga, supplements, and meditation. Indeed, acupuncture shows promise in the treatment of obesity and overweight in general populations. A recent meta-analysis reported that acupuncture, in particular auricular acupuncture and electro-acupuncture, was more efficacious than sham acupuncture for reducing BMI (MD − 0.47 kg/m
2) as well as body fat mass (MD − 0.66 kg), waist circumference (MD − 2.02 cm) and hip circumference (MD − 2.74 cm) but not for reducing body weight overall [
20]. Mechanistic studies have suggested multiple responses to acupuncture including appetite suppression [
21,
22], modulation of leptin and ghrelin [
23‐
25] and improved insulin sensitivity [
26‐
31]. Further, acupuncture may alleviate co-morbid anxiety symptoms in people with obesity [
23,
32,
33]. Given that acupuncture is a relatively safe treatment [
34‐
36] and may have additional benefits in women with BC including relief of chemotherapy-induced peripheral neuropathy [
37], aromatase-inhibitor induced arthralgia [
38,
39], menopausal symptoms [
40] and lymphoedema [
41], it may represent a useful adjunctive therapy that can assist women in managing a number of bothersome symptoms and manage weight. To the best of our knowledge, there are no studies examining the effectiveness of acupuncture for weight loss in women with BC, and such research appears warranted.
Women in our sample were also willing to trial meditation, yoga and nutritional supplements for weight management. In non-BC populations, limited evidence suggests that mindfulness meditation may help people improve eating behaviours (such as reducing the amount of emotional eating), increase physical activity, and reduce anxiety and stress [
42‐
47] while two pilot studies using mindfulness-based techniques for weight management in women with BC have reported promising findings for weight loss and eating behaviors [
48,
49]. Again in non-BC populations, yoga may be effective for reduction of BMI compared with usual care (SMD -0.99) [
50], while a pilot trial in women with BC reported a reduction in waist circumference of 3.1 cm and improvements in quality of life [
51]. A range of nutraceutical supplements may have modest effects on weight [
52‐
55]. Given the interest in using these complementary modalities to assist weight loss, and the potential for additional benefits such as for mental health, further clinical research into the effectiveness and efficacy of these low risk mind-body interventions as an adjunct to lifestyle interventions is required.
This survey has some strengths and limitations. We achieved a higher than expected response rate from the BCNA Review and Survey Group, which is typically 10% (email communication with BCNA Review and Survey Group,3 Oct 2017). We were also able to recruit across Australia, with the percentage of respondents from each Australian State and Territory in our study being similar national averages on BC incidence sourced from the Australian Institute of Health and Welfare cancer data [
56]. However, the majority of women from the BCNA Review and Survey Group did not respond, and the demographics of this group are also unclear. Also, the total numbers of women who used CM for weight management were small. These factors limit the validity of our findings.
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