Discussion
The present study has been designed to shed light on the effect of PRE as an alternative therapeutic method to reduce pain and investigate its positive impact on the quality of life (QoL) and AD status in patients with BC receiving AI. Pain was significantly reduced within the study group and between groups in pain sub-scores. Musculoskeletal pain is a serious problem, which could be seen by up to 50% of patients with BC receiving AI.28 Laroche et al. suggested that pain was a mostly psychological problem rather than being affected by genetic and biological factors.29 Presant et al. reported that therapeutic management and patient’s educational background were also significant factors for pain relief.28 Our findings broadly support the work of other studies in this area linking to improve pain scores with PRE.
Pharmacological approaches have been identified as primary effective options to cope with AI-related pain in literature. At the same time, other complementary medicine strategies like acupuncture, nutritional supplementation, relaxing techniques and physical exercises are suggested as secondary options.30 Some exercise methods were previously used to reduce pain and related emotional problems with limited success in AI users. Among these, aerobic exercise, resistance exercise or methods combining physical exercise with other methods seem to be efficacious techniques to cope with pain in the literature.31-34The present study showed that, although the pain scores of the study group were higher than the control group before the intervention, it decreased even more after PRE. This shows us that they use the relaxation technique effectively to cope with pain. Improvements in the pain scores of the PRE group corroborate the literature findings.
Yoga and Tai-Chi are reported to be relaxation techniques, which are recommended to improve wellbeing and reduce pain in patients with BC receiving AI.23,35 PRE aims to relax most of the muscles in the form of a ‘contract and relax’ method, which is distinct from Tai-Chi and Yoga. PRE was performed as an exercise method to achieve muscle relaxation in the present study. Integrative therapies are recommended to reduce adverse effects of treatments, although more substantial evidence is needed to achieve a consensus for wider use.36,37 PRE should be considered as an integrative therapeutic method to reduce pain in patients with BC receiving AI.
The present study did not find a significant difference in QoL and ES outcomes with the implementation of PRE. There is no consensus in the literature on the positive effect of exercises for QOL and ES in patients with BC. Some of the literature studies suggest exercise to improve QoL and ES in patients with BC receiving AI.38-40 In particular, the aerobic and resistance training seem to be effective in improving QoL and ES in AI-receiving patients with BC.33,34 On the other hand, Cadmus et al. showed that exercise did not affect QoL in either recently diagnosed or post-treatment in patients with BC.41 Therefore, QoL and ES seem to need more substantial evidence among treatments of patients with BC.
The randomized design and a high rate of technical compliance of the patients with the scheduled exercise program constitute the power of this study. Furthermore, the high rate of (81%) adherence of the patients to the program was satisfactory during the present study. In contrast, the small sample size of the groups and short (one-day-long) supervision program in a week are its limitations. Moreover, lack of long-term follow up of participants could be considered as the absence of compliance of this study.
Conclusions
This study indicate that supervised and home-based PRE is efficient in reducing the pain sub-scores (PS and PPE) of patients with BC receiving AI. PRE has no positive effect on QoL and AD scores. Further studies are needed to reach a consensus to recommend PRE as one of the primary and long-term treatment options for reducing AI-related pain in patients with BC. Long-term follow-up procedures may be important for future studies to ensure patient compliance with complementary therapies.