This cross-sectional study of self-reported activities in the fields of physical activity, eating habits, and use of CAM was conducted in a population of patients with early breast cancer (survivors) that may be considered representative for patients with early breast cancer in Eastern Switzerland. Compliance with completion of the questionnaire was high and understanding of the questions was supported by attending specialist breast nurses. Around half of all patients indicated activities, interest in getting more information about the fields and declared willingness to present on an extra occasion. For physical activity, we explored whether patients expressing interest in more activity are really ready to engage actively. All interested patients were offered a free voucher for training with personal instruction by a certified physiotherapist. Interestingly, nearly half of these patients declined this offer despite declaring interest in the questionnaire. Furthermore, only 4% of the vouchers were eventually used. This pattern is not unusual with psychological research reporting that less than half of lifestyle intentions are successfully realised leaving a considerable ‘intention-behaviour gap’ . Besides this, we think that the surprisingly low rate questions the nature of the training offered or the strength of the actual interest and indicated willingness. Many patients who accepted the voucher reported to be physically active already. This may explain in part the low response rate. The rate of declared physical activity was above what had been expected  although a direct comparison is limited by the cut off for physical activity used in our study (“at least 60 min/week” and not 150 min/week as recommended to have an impact on disease recurrence ). This may also be reflected by a median body mass index of 24.5 kg/m2 what is lower than reported in other studies conducted in the field of exercise interventions in Western patients with early breast cancer [20, 22]. This possibly reflects a rather healthy life style in many Swiss patients, at least those presenting in our centre. This view is supported by a fairly high life expectancy in Swiss women (84.6 years at birth) and our findings that 87% of all participants reported to pay special attention to eating habits, a rate which is above reported rates in other Western countries such as the United States . Furthermore, a strong predictor for reporting healthy eating was physical activity. Consistent with other data, we did not find a correlation of physical activity or attention to eating habits with participants’ vital signs, body composition, smoking habits or breast cancer characteristics (data not shown) . These findings suggest that activities are rather determined by what is believed to be beneficial by certain patient groups than by the actual risk for recurrence arising from tumour stage and biology.
Nearly half of the participants reported engaging in one or the other field of CAM. Higher education, physical activity and younger age were the strongest predictors of CAM. This rate is similar to that reported in the literature [25, 26]. Though most CAM activities reported in our survey can be considered safe, the high rate of complementary therapies suggests that asking patients specifically about the use of such approaches is probably reasonable to ensure safety, especially when combined with conventional therapies. In the case of CAM, there was a remarkable association of the use and willingness to present on another occasion for special counselling, possibly reflecting the strongest health-belief of the fields studied here. It remains uncertain whether such interest may lead to active participation in institutional programs.
Interestingly, nearly all patients indicated to have changed their life after breast cancer diagnosis. Most reported positive effects like finding it easier to look after themselves or to have reduced stress.
The strengths of our study include the prospective design, the use of prospectively defined research questions and hypotheses allowing for robust sample size calculation, the completeness of data and information on non-compliance minimizing selection bias. The studied cohort also underwent external validation by comparison with data obtained from the cancer registry.
Limitations of this questionnaire-based survey include the possibility of answers intended to please (in contrast to entirely anonymous questioning or objective measures) and of inaccurate answers e.g. with self-reported activities where only the options none, once per week or more than once per week were offered. The validity of a 30 minute cut-off can also be questioned especially as 150 minutes of moderate intensity, physical activity is considered the level needed to be associated with a lower recurrence risk [21, 27]. Furthermore in some cases the boundary of what is to be considered CAM seems arbitrary (e.g. intake of vitamins or teas) and may not have been interpreted in the same way by all patients.