Abstract
Background. Due to the limitations and side effects of conventional cancer treatment, especially in relation to quality of life (QOL), patients are increasingly utilizing complementary and alternative medicine (CAM) to supplement health-related outcomes. However, evidence for the safety and efficacy of such treatments is lacking. The purpose of the current review was to investigate evidence for the role of one CAM, medical Qigong (MQ), in supportive care. Methods. The literature was searched for reported effects of MQ in improving QOL, immune function, and survival in cancer patients. Results. Although many studies possessed methodological limitations and small sample sizes, encouraging evidence was found for the effects of MQ on these health-related outcomes. More robust evidence in the form of randomized controlled trials with larger sample sizes also reflected positive results for the role of MQ in improving QOL, mood and fatigue parameters, and reducing inflammation. Conclusion. Given such encouraging results, further research is recommended in methodologically sound approaches to further delineate the action of MQ. These findings support the utilization of MQ by cancer patients and the place for such programs in comprehensive cancer care.
Introduction
Despite improvements in the treatment of cancer over the past 50 years, there are considerable limitations in conventional care. 1 The disease itself and standard treatment are associated with significant physical, psychological and emotional stress, side effects, and toxicity. 2 Specifically, cancer has been shown to deleteriously impact on individuals’ quality of life (QOL) through emotional distress and side effects of treatment.3,4
Due to the limitations of, and negative outcomes resulting from, conventional cancer therapy, patients are increasingly turning to complementary and alternative medicine (CAM) to supplement their care. In Australia, it has been reported that 65% of cancer patients engage in CAM use. 5 Despite the high prevalence of CAM use, data are lacking about the safety and efficacy of such treatment methods.
One form of CAM frequently used by cancer patients is medical Qigong (MQ). MQ is a form of mind–body traditional Chinese medicine that has a history of more than 5000 years. 6 MQ practice involves a combination of coordinated gentle exercise and relaxation through meditation and breathing. The theory behind MQ involves facilitating a free flow and balance of energy to combat blockages in this energy flow thought to contribute to discomfort and illness. Western models of medicine can account for the operation of MQ in terms of the “relaxation response” and psychoneuroimmunology mechanisms.7,8 It is purported that MQ is able to achieve reduced emotional and physical tension and improved immune function through its ability to stimulate homeostasis of the sympathetic and parasympathetic nervous systems through hypothalamic action.
Many positive health-related impacts from the use of MQ have been reported in the literature, including decreased heart rate, 9 decreased blood pressure, 10 lowered lipid levels, 11 decreased levels of circulating stress homes, 12 and improved immune function.12,13
Despite its use in the context of supportive cancer care, there is little evidence of the systematic evaluation of its safety, efficacy, and role. Such evidence is important to optimize patients’ health-related outcomes and guide doctor–patient communication and recommendations in relation to participation in MQ therapy. The aim of the current article was to review the literature in order to examine the reported effects of MQ on QOL, immune function, and survival in cancer patients. The analysis was divided into 2 parts—evidence of the role of MQ in improving QOL and evidence supporting the place of MQ in improving immune function and survival.
Methods
A literature search of electronic databases was conducted up to September 2010. Databases searched included PubMed (any date), MEDLINE (from 1950), ProQuest (from 1950), ScienceDirect (from 1950), Cochrane Library (from 1991), CINAHL (from 1982), EMBASE (all years), PsycInfo (from 1806), and the Qigong and Energy Medicine Database (www.qigonginstitute.org). All databases were searched using the search terms “Qigong” and “Cancer.” We also searched reference lists of selected articles and reviews. An additional 20 articles, collected from personal communication (Chinese abstracts translated into English by the Qigong Institute), were also reviewed.
For the purpose of this literature review, the published articles exploring the effect of Qigong treatment on cancer outcomes were categorized into the following areas: quality of life, immune function, and survival rate.
Study Selection
Published articles, including abstracts from conference papers, that reported original data from a randomized controlled trial (RCT) or controlled clinical trial of a Qigong intervention for cancer patients were eligible. Inclusion criteria were being published in English or having been translated into English and having at least 10 human subjects, including an evaluation of QOL including emotional well-being, functional well-being, physical well-being, and social well-being or including a measure of immune function, inflammation, and/or survival.
Results
The searches identified 295 potentially relevant articles, of which 213 duplicated articles were excluded. Of the 82 full articles, 8 articles met the eligibility criteria and were reviewed (Figure 1). An additional 2 articles found in reference lists were reviewed. Of these 10 articles, 4 articles measured both subjective and objective outcomes.
Four studies measured both subjective and objective outcome.
Effect of Medical Qigong on QOL
Of the 6 studies included within this category, 3 were RCTs and 3 had a quasi-experimental pre-/postintervention design. All studies recruited participants from hospitals or cancer centers. Five studies failed to meet the statistical power required to detect differences in the QOL of cancer patients.
Sample sizes varied from 18 to 211. Four studies had small samples (≤67).14-17 Only 1 study included more than 200 participants. 18 Three studies recruited patients from a homogeneous group, women with breast cancer, 17 advanced gastric cancer, 15 and advanced liver cancer, 16 whereas 3 studies included patients suffering from heterogeneous cancers.14,18,19 Two studies failed to provide sufficient detail regarding the stage of disease of the participants.17,18 Five studies described the style, practice time, and duration of their Qigong intervention programs,14-17,19 but 1 study failed to describe the details of the Qigong intervention program. 18
Chen et al 20 reviewed 21 clinical studies on the effect of Qigong on cancer patients. Of these studies, 8 measured and reported improvements in subjective symptoms related to QOL such as pain levels, appetite, sleep, diarrhea, and bowel movement and energy as a secondary outcome measurement. Five of the 8 studies, however, neither described the tool used to measure physical symptoms and side effects nor provided any statistical data. Two studies21,22 reported improvements in appetite, diarrhea, bowel movement, and sleep as a percentage of improvement without reporting the significance level of this improvement. Thus, it is difficult to interpret the study findings. Nevertheless, as Chen et al 20 argued in his review, these studies support the need for further research to explore these effects using more methodologically rigorous designs.
More recent Qigong studies have used more robust designs.14,16,19 Studies in this category are shown in Table 1. In 2002, Wang and Ye 18 investigated the therapeutic effects of Qigong on psychological symptoms during the rehabilitation of cancer patients in China. They recruited 104 patients from a Qigong rehabilitation unit as an intervention group and 107 patients from another cancer clinic as the control. Thus, sample bias may have affected the results. Anxiety, depression, and personality were measured in both groups with the Eysenck Personality Questionnaire and Zung’s Self-Evaluation Anxiety and Depression Scale at baseline and at 3 months post-Qigong intervention. The investigators reported that Qigong was significantly related to a reduction in the symptoms of anxiety and depression (P < .01). This was the first study designed to measure the effect of Qigong on the QOL of cancer patients in China, as most of the previous studies were designed to measure biological and physiological outcomes.
Studies Conducted Since 2000 Assessing the Impact of Qigong on QOL
Abbreviations: QOL, quality of life; RCT, randomized controlled trial; CCT, controlled clinical trial; NS, not significant; FACT-G, Functional Assessment of Cancer Therapy–General; FACT-T, Functional Assessment of Cancer Therapy–Therapy; MOS SF-36, Medical Outcome Study, Short Form-36; SCL-90-R, Symptom Checklist 90–Revised; CRP, C-reactive protein.
Another attempt to measure the QOL of cancer patients subject to Qigong intervention was conducted with advanced gastric patients. In 2003, Hong 15 studied the effects of Qigong on the side effects of chemotherapy in advanced stomach cancer patients in Korea. Twenty-four patients were nonrandomly divided into 2 groups: group 1 (n = 12) received Qigong with chemotherapy and group 2 (n = 12) chemotherapy only. The main study outcome, fatigue, was measured by the Piper Fatigue Scale, the difficulties of daily activity by a subscale of the Medical Outcome Study, Short Form-36 (SF-36), and nausea and vomiting by self-report on a scale ranging from 0 to 5. Study results showed that compared with the control group, the Qigong intervention reduced fatigue (P < .001), difficulty in carrying out daily activity (P < .001), and also nausea and vomiting (P < .005). Unfortunately, the nonrandom allocation of subjects may have biased the results. Although this study used validated instruments to measure fatigue and physical function, major limitations of the study were the nonrandomized design and small sample size.
An RCT in 2004 investigated the effects of Qigong on survival as the primary outcome, with QOL as the secondary outcome. Lam 16 investigated the effect of Guolin Qigong combined with transcatheter arterial chemoembolization (TOCE) on the survival rate and QOL of patients with unresectable hepatocellular carcinoma in Hong Kong. Fifty-eight patients were randomized into 2 groups receiving Qigong combined with TOCE (n = 29) or TOCE only (n = 29). The Qigong intervention consisted of a 2-hour session conducted twice weekly for 6 weeks in class and for 24 weeks at home for 3.5 to 5 hours daily. QOL was measured with SF-36 and the Functional Assessment of Cancer Therapy–General (FACT-G). The differences between the intervention and the control groups were not significant for QOL. This study suggests that Guo Lin Qigong is not effective in improving the QOL of advanced cancer patients. 16
This was the first study with an RCT design that attempted to evaluate the effect of Qigong on QOL. While validated measures were used to assess QOL (the FACT-G and SF-36), the author failed to calculate the sample size required to ensure detection of group differences in QOL. However, the study supports the view that Qigong is, in general, safe and tolerable to patients with an advanced stage of cancer.
In Taiwan, Lee et al 17 conducted a clinical trial in 2006 to examine the effects of Qigong on symptoms of distress and psychological distress in breast cancer patients who underwent chemotherapy. A quasi-experimental design was employed. The intervention group (n = 32) participated in the Chan-Chuang Qigong for 21 days plus chemotherapy, whereas the control group (n = 30) received chemotherapy only. Symptoms were measured with the McCorkle and Young Symptom Distress Scale, and psychological distress was measured with the Symptoms Checklist 90–Revised (SCR-900-R). The results showed significant group differences (P < .05) in pain, numbness, heartburn, and dizziness over the 3 weeks of therapy. The authors concluded that Qigong therapy may decrease symptom distress in breast cancer patients who were being treated with chemotherapy. However, while there was a trend for greater improvement in the intervention versus control group, the group difference in psychological distress was not statistically significant.
The weakness of this study was that the intervention was not long term. Furthermore, the nonrandom allocation of subjects may have biased the results. Nonetheless, this study does suggest that a short-term (21 days) Qigong intervention might be effective in relieving the physical distress of breast cancer patients who are undergoing chemotherapy treatment.
In a pilot study with 18 patients, Oh et al 14 conducted a preliminary investigation into the feasibility of using Qigong to improve QOL. Eight heterogeneous cancer patients were randomized to undertake MQ once or twice a week for 8 weeks, with 10 patients randomized to the control group. After the 8 weeks, the intervention group reported improved QOL and reduced symptoms of side effects of cancer treatment. However, due to the small sample size of the study, these results did not reach significance.
In a larger RCT in 2009, Oh et al 19 again compared QOL, fatigue, and mood in 162 heterogeneous cancer patients, 79 randomized to receive Qigong twice a week for 10 weeks and 83 randomized to the control group. Regression analyses found significant improvements in QOL and significant reductions in fatigue and mood disturbance in the intervention group when compared with the control. Such results suggest MQ can improve important health-related outcomes in cancer patients. The limitations of the study include the fact that as the control group was only given usual care, the extra attention given to the intervention group was not controlled for. Furthermore, neither participants nor instructors were blind to the treatment condition and the completion rate was quite low.
Effect of Medical Qigong on Immune Function and Survival
Chen and Yeung 20 also reviewed 13 studies that had been presented at Qigong conferences and which assessed physiological changes after Qigong therapies. Most of these studies showed improvements in survival time, immune function, physical strength, and reduced tumor size in patients who practiced Qigong. However, the design of all these studies was weak and this precludes any conclusion regarding the impact of Qigong on medical outcomes. Three abstracts available in an English translation and 3 published in an English medical journal and 1 thesis are reviewed here. Summaries of these publications and 2 further studies are shown in Table 2.
Impact of Qigong on Immune Function and Survival Rate of Cancer Patients
Abbreviations: RCT, randomized controlled trial; CCT, controlled clinical trial; NS, not significant; WBC, white blood cell; RBC, red blood cell; CRP, C-reactive protein.
In 1988, Luo and Tong 23 conducted an RCT of the effect of Qigong on malignant tumors. Eighty patients with various malignant tumors participated in the study. The authors randomly assigned cancer patients to 3 groups and compared the red blood cell count (RBC), white blood cell count (WBC), and level of serum hemoglobin and platelets and the T lymphocyte conversion rate before and after 60 days of Qigong practice. Group I received Qigong only (n = 30), group II received chemotherapy only (n = 25), and group III received Qigong plus chemotherapy (n = 25). The authors reported that group I had a significant rise in WBC, RBC, and serum hemoglobin (P < .01) and T-lymphocyte conversion rate (P < .05) after treatment whereas Group II had significant lowering (P < .01) of all outcomes. Group III had significant elevation of serum hemoglobin, RBC, and platelet count (P < .01), but the WBC count and T-lymphocyte conversion rate (P > .05) remained unchanged. The T-lymphocyte conversion rate of group II was not reported. This study reported the difference pre- and posttreatment within groups but did not report the between-groups results. This was one of the earlier RCTs examining the effect of Qigong on immune function and as such served a useful purpose. However, it had weaknesses in its data analysis and report. Furthermore, while this study did report the short-term effect of chemotherapy on suppression of immune function it did not discuss the possible effects of chemotherapy, which may contribute to survival.
In 1993, Wang et al 24 randomly assigned various cancer patients into 2 groups: one receiving Qigong plus chemotherapy (n = 32) and the other receiving chemotherapy only (n = 30). The patients who practiced Qigong plus chemotherapy experienced improved health with a stable WBC count. The 29 patients who received Qigong plus chemotherapy (n = 32) completed chemotherapy and showed reduced medical symptoms. Patients in the chemotherapy-only group experienced declining health and a lower WBC count. Only 18 patients completed the chemotherapy; 12 patients stopped chemotherapy due to severe side effects. This article reported a comparison of WBC without reporting the appropriate statistics. It also did not use a validated instrument to measure health status and side effects resulting from chemotherapy to compare between groups. Although this study shows some evidence of the effect of Qigong on chemotherapy patients, the poor data analysis precludes firm conclusions.
A study by Fu et al 25 randomized 186 patients with gastric cardiac adenocarcinoma postsurgery into 4 groups: no further treatment (n = 48), chemotherapy (n = 42), herbal treatment only (n = 46), and herbal treatment plus Qigong (n = 50). They measured the survival rate in years 1, 3, and 5. The results were as follows: surgery only, 80.1%, 37.5%, 20.8%; chemo, 85.7%, 45.2%, 25.1%; herbal, 84.5%, 43.5%, 26.2%; Qigong plus herbal, 86%, 64%, 34%, respectively. As the results show, Qigong plus herbal medicine treatment survival rates were higher than those in the other groups. This study reported descriptive data without appropriate statistical data analysis comparing the groups.
In 2004, Lam 16 investigated the effects of Qigong on survival as the primary outcome. This study investigated the effect of Guolin Qigong combined with transcatheter arterial chemoembolization (TOCE) on the survival rate of patients with unresectable hepatocellular carcinoma. Differences in the survival rate between the intervention and the control groups were not significant. This study suggests that Guo Lin Qigong is not effective in improving survival of advanced cancer patients. 16 However, this study failed to meet the sample size requirements to detect differences in survival. A future study with an adequate sample size is needed to confirm the effect of Qigong on the survival of cancer patients.
A study of Yeh et al in Taiwan, 26 was based on a clinical trial that examined the effects of Qigong on complete blood counts in breast cancer patients who underwent chemotherapy. This study reported the between-groups statistical differences. A quasi-experimental design was employed. The intervention group (n = 32) participated in Chan-Chuang Qigong plus chemotherapy for 21 days, whereas the control group (n = 30) received chemotherapy only. Blood test results revealed group differences in white blood cells (P < .001), platelets (P < .001), and hemoglobin (P < .001), over the 3 weeks of therapy. The result was similar to an earlier study. 24 This result suggests that Qigong therapy may decrease leukopenia in breast cancer patients treated with chemotherapy. 26 However, this study had a bias with nonrandom allocation of subjects into the intervention. A replication with a bigger sample size and appropriate RCT would be required to confirm the results.
In the pilot study conducted by Oh et al, 14 the role of Qigong in inflammation of cancer patients was also explored. Eight heterogeneous cancer patients were randomized to undertake MQ once or twice a week for 8 weeks, with 10 patients randomized to the control group. After the 8 weeks of intervention, the treatment group recorded reduced levels of the inflammation biomarker C-reactive protein. However, statistical significance was not reached due to the limited sample size.
In a subsequent larger RCT, Oh et al 19 explored the inflammatory biomarker levels in 79 heterogeneous patients randomized to receive Qigong twice a week for 10 weeks and 83 patients within the control group. Regression analyses found significant reductions in inflammation in the intervention group compared with the control suggesting a role for Qigong in reducing inflammation, although the implications of this for survival are unclear.
Discussion
Effect of Medical Qigong on QOL
Overall, all the studies identified had significant methodological flaws. Of the 6 clinical trials with a control group, 3 were RCTs.14,16,19 However, 2 of these studies did not have the statistical power required to detect differences in the QOL of cancer patients.14,16 Furthermore, while 3 studies did report the dropout rate, the other 3 failed to do so.15,17,18 In terms of QOL outcome measures, all studies used self-report questionnaires as their main outcome measures. Due to the nature of the interventions, proper blinding of participants was not possible. However, all studies reported the method of statistical data analysis they used.
Evidence on the impact of Qigong on the symptoms of cancer patients, including anxiety, depression, personality, fatigue, and symptoms of distress, was mixed (see Table 1). Furthermore, 1 RCT with a Qigong intervention on advanced liver cancer patients failed to detect any improvement in their QOL. 16 However, this RCT reported that there were no adverse effects on cancer patients who completed the Qigong intervention. Although finding no statistically significant results, the pilot study RCT conducted by Oh et al 14 indicated the potential for Qigong to improve QOL and reduce inflammation and the side effects of cancer treatment. A subsequent RCT with a larger sample size showed that indeed MQ was able to improve patients’ overall QOL and mood status as well as reduce treatment side effects and inflammation levels. 19 Thus, the evidence regarding the effectiveness of the reviewed Qigong interventions on overall QOL and psychological symptoms is inconclusive. All studies have suggested that interventions using Qigong with cancer patients are feasible and safe. The RCT conducted with a sufficiently large sample size showed encouraging results regarding the role of MQ in supportive cancer care. Further research is needed to clarify whether Qigong interventions enhance QOL for patients with cancer. Future studies need to use an RCT design and to recruit larger numbers of participants in order to meet the requirements of statistical power and to offset loss of follow-up.
Effect of Medical Qigong on Inflammation and Survival
Of the 7 studies included, 5 were RCTs and 2 had a quasi-experimental pre-/postintervention design. All studies recruited participants from hospitals and recruited patients from single institutions. Five study samples were small (≤80) while one had 186 participants and the other 162.19,25 Three studies recruited patients from homogeneous groups: women with breast cancer, 26 people suffering from gastric cardiac adenocarcinoma, 25 and people with advanced liver cancer. 16 The other 4 studies included patients suffering from various cancer diagnoses.14,19,23,24 Four studies failed to provide sufficient detail regarding the stage of disease of participants. Four studies described the style, practice time, and duration of the Qigong intervention program,14,16,19,26 but the other 3 studies failed to describe in detail the Qigong intervention program.
Of the 7 clinical trials with a control group, 5 were RCTs.14,16,19,23,24 In terms of outcome measures, 5 studies used blood tests to measure WBC, RBC, hemoglobin, CRP, and the T-lymphocyte conversion rate. Two studies involved clinical observation to measure survival rate as the main outcome measure.16,25 Three studies reported the dropout rate.14,16,19
Evidence of the impact of Qigong on the immune function of cancer patients was emerging but consistent. Two RCTs23,24 and 1 controlled clinical trial 26 measuring WBC demonstrated an effect of Qigong on immune function. Chen et al 20 also reported that 6 observation studies improved the level of T lymphocytes and NK cells after Qigong practices.
Furthermore, 1 study of a Qigong intervention delivered to adenocarcinoma patients reported improvement of survival rate, 25 while another study with advanced liver cancer patients did not. 16 However, the study that reported an improvement in survival did not report the statistical significance of differences between the groups.
In conclusion, while 6 studies have reported a positive impact of Qigong on physiological outcomes such as immune function, survival rate, and leukopenia, most studies had significant methodological weaknesses such as limited sample size, inadequate data analysis, and lack of randomization. The RCT conducted by Oh et al 19 provided the most robust evidence for the role of Qigong in reducing inflammation. Further studies with better research designs and analysis methods are needed.
Footnotes
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
The authors received no financial support for the research, authorship, and/or publication of this article.