To our knowledge, our study is the first randomized controlled trial with adequate statistical power which has been used to measure the impact of MQ in patients with cancer. The findings provide evidence for the impact of MQ on QOL, fatigue, mood status and inflammation in patients with cancer, major issues for cancer patients.
Our major findings were that scores on total QOL and all domains (PWB, SWB/family well-being, EWB and FWB) measured by the FACT-G were significantly improved in participants who completed the Qigong intervention at 10-week follow-up compared with the usual care control group. These results are consistent with the study of Tsang et al. [21
] of MQ in elderly patients with chronic illness. It is sometimes the case that interventions may lead to improvements in outcomes that, while statistically significant, may not be clinically relevant and important. This does not appear to be the case in this study, where individuals in the MQ intervention scored an average of 8.23 points higher on the FACT-G measure of QOL than individuals in the usual care control group at 10-week follow-up. A 5- to 10-point difference on the FACT-G is considered to represent both a clinically and a socially important difference in QOL and functioning in cancer patients [22
Another significant finding from this study was the positive effects of MQ on inflammation as measured by the CRP. While the precise mechanism through which MQ is able to decrease inflammation is unclear, one possible pathway is through MQ’s effect on the immune system. A number of studies have indicated that MQ leads to improved immune function [23
]. These findings indicate a need for further research on the impact of MQ on biological changes, such as immune function, cytokines and inflammation, in order to more fully understand these effects.
In this study, patients in the MQ intervention group experienced significantly less CRF than those in the usual care control group. A change of >3 points on the FACT-F measure of CRF is considered to represent a clinically important change in fatigue in a cancer population [25
]; patients in the MQ intervention group reported a 6.34-point change in CRF as measured by that scale. Thus, the reduction in CRF reported was clinically as well as statistically significant. Results are consistent with other research which has found that MQ can lead to improvements in CRF [26
] and to research that has linked mindfulness-based stress reduction [27
], relaxation breathing exercises [26
] and yoga [28
] to reduction of CRF in a range of cancer populations. Physical exercise is also often recommended by cancer care professionals as a method of minimizing CRF and improving QOL. However, recent randomized controlled trials have reported that fatigue and QOL were not improved with physical exercise [29
]. The current study finding indicates that management of CRF and QOL may be more effective if improvements in psychological and emotional functioning are targeted as well as physical functioning, as in the case of the MQ intervention. More research may be necessary to clarify the relationship between CRF, QOL, MQ and physical exercise.
Moreover, participation in the MQ intervention led to better total mood status among cancer patients, specifically reduced tension, anxiety and depression and increased vigor. This is supported by previous research which found an effect of MQ on mood in elderly patients with chronic illness [21
], although another study found no impact of Qigong on mood in patients with cancer [31
]. There may be differences in the delivery of Qigong which account for these divergent results, emphasizing the need for very clear descriptions of intervention content in evaluation studies.
Finally, no adverse effects of MQ were reported by the cancer patients in this trial, which is reassuring. Safety of MQ practice for cancer patients is also supported by previous literature [32
Although these results are positive and promising, there are some limitations to the study and methodological approach that should be taken into account when interpreting the results. First, inclusion of a control group receiving usual care means that the significant results may have been due to the additional attention received rather than the intervention. A usual care control group was chosen rather than a placebo sham group due to the early stage of this research. If a difference was detected between the groups, a subsequent larger study was planned to control for the effect of attention, and indeed this is now in the planning stage.
Secondly, contrary to recommendations for drug trials, neither the participants nor the instructors were blind to condition. Due to the nature of the intervention, it was not possible to make use of a blinding protocol. As such, it is possible that the benefits reported from the MQ intervention were due to experimental bias and confounding factors (e.g. extra care versus non-extra care), participants’ expectancy (placebo effects) and social interactions. To reduce the likelihood that patients who knew they were in the intervention arm of the study would provide socially desirable responses, a third independent person distributed and collected the pre and post intervention questionnaires and carried out all data entry.
In this study, the completion rate was relatively low (76%) compared with other similar studies (85%) [30
]. Some studies that reported a low dropout rate (15%) recruited early-stage breast cancer patients [33
], while studies that have reported a high dropout rate (35%) have recruited cancer patients with all stages of disease [34
], similar to the current study. Dropout rate may be more dependent on the health status of participants than on other factors.
Participation in this study was voluntary and that may have created a potential selection bias, with those patients interested in Qigong participating and those with no interest in Qigong declining. This may limit the generalizability of the findings but does not invalidate the results for this sample.
Moreover, this study investigated the short-term benefits of the MQ intervention but not the longer term. It may be worthwhile to investigate whether the benefit is sustained in the long term with participants who continue to practice MQ at home.
Despite these limitations, the findings of this study are positive and provide evidence that MQ is safe and effective in improving QOL, fatigue, mood status and reducing symptoms, side-effects and inflammation in cancer patients. Further studies examining long-term benefits of MQ, including a potential association between improvement in QOL and survival rate, may provide additional information that may assist patients with cancer and clinicians in providing optimal comprehensive cancer care.