Benefits of Qigong as an integrative and complementary practice for health: a systematic review

Objective: to analyze, in the literature, evidence about the benefits of the integrative and complementary practice of Qigong with regard to the health of adults and the elderly. Method: a systematic review by searching for studies in the PubMed, CINAHL, LILACS, EMBASE and Cochrane Library databases. Randomized and non-randomized clinical trials were included; in Portuguese, English and Spanish; from 2008 to 2018. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses strategy was adopted, as well as the recommendation of the Cochrane Collaboration for assessing the risk of bias in the clinical trials analyzed. Results: 28 studies were selected that indicated the benefit of the practice to the target audience, which can be used for numerous health conditions, such as: cancer; fibromyalgia; Parkinson’s disease; Chronic Obstructive Pulmonary Disease; Burnout; stress; social isolation; chronic low back pain; cervical pain; buzz; osteoarthritis; fatigue; depression; and cardiovascular diseases. However, there was a great risk of bias in terms of the blinding of the research studies. Conclusion: the practice of Qigong produces positive results on health, mainly in the medium and long term. This study contributes to the advancement in the use of integrative and complementary practices in nursing, since it brings together the scientific production in the area from the best research results available.

fact that PICs have their demand increased, as well as their insertion in the SUS, points to the beginning of a movement in Brazil in the search for qualifying the form of health care offered to the population, which is gradually more comprehensive, resolutive, and universal (1) .
Qigong is a TCM PIC that meets this perspective of health care. And, as already discussed, it is a practice with a high level of recognition for its positive health results. During the process, there is an improvement in the transport of energy and blood through the established body-mind relationship, which influences the blood, the essence, body fluids, and the mind, essential to the human being. In this way, it is possible to adjust and harmonize the flows of Qi and the Yin-Yang of the body, therefore promoting health (6) .
A study in the area has progressively explored the results of this therapy in different target audiences, for example, people with advanced age and others with chronic health conditions that are not susceptible to transmission, in order to understand its influence in terms of health (6) . However, more evaluations, from studies with recognized methods, are necessary with regard to the physiology involved in the results of therapy, so that it is possible to develop what is known in the area regarding its relationship with the health of practitioners, a reason that encouraged the development of the present study.
Practices that develop both physical and mental conditions and Quality of Life (QoL), such as the PICs, are the foundation for the search for quality nursing care, carried out during the sharing of knowledge between professionals and users of health. In this sense, there is an appreciation of their active participation in this process (2) .
The fact that nurses use PICs is related to a humanizing movement for the integration of care, which covers its dissemination, as well as the act of making them legitimate in this context. Although the literature presents solid evidence, there is little use of these practices by professionals in the area and patients (1)(2) .
Therefore, in order to build a scientific contribution, in addition to optimizing the action of nursing in both care and health production, research that explores the results of the PICs, such as Qigong, with a focus on those related to nursing, are essential. That said, the objective of this systematic review was to analyze, in the literature, evidence about the benefits of the integrative and complementary practice of Qigong with regard to the health of adults and the elderly.

Method
The literature Systematic Review (SR) method makes it possible to gather, analyze, and synthesize scientific productions regarding a certain clinical issue, so that it is possible to understand, discuss, and establish clinical actions based on evidence (7) .
The methodological trajectory followed was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), through its checklist of items and flow chart for the development of a SR (8)(9) .
In order to construct the research question of this  The following were adopted as inclusion criteria: The exclusion criteria adopted were the following: not selecting research studies related to medical Qigong (external); which did not discuss assessing the effects of Qigong or did not present a correct definition of it; and which presented only clinical trial protocols, without obtaining results.
The search was carried out concomitantly in November 2018, through the five databases mentioned.
When crossing the descriptors, 334 articles were found. In order to manage the research studies, the Rayyan QCRI ® and EndNote Web ® software were used.
The same programs were used to export, organize, and filter studies with respect to duplication in the databases.
The studies were pre-selected when reading titles and abstracts and, finally, they were selected for this review through complete reading in order to include them in the sample. Pre-selection was also carried out by reading the title and summary and, finally, selecting the studies for the final review by reading them in full for inclusion in the sample. were carried out, so that it was possible to classify them according to the evidence hierarchy (11) .
The critical evaluation of the studies was carried out based on the recommendation of the Cochrane Collaboration (12) for assessing the risk of clinical trial bias. It is a tool that allows for the assessment of several types of bias found in clinical trials, being organized into seven domains, with three categories each, namely: high risk of bias, low risk of bias, and uncertain risk of bias. Such an instrument was chosen because it was necessary to analyze the level of the research methodology found in the SR, so that the results from the scientific evidence in the literature were reliable.

Results
28 studies were selected that were compatible with the inclusion criteria adopted for this SR, and studies were not added from the review of the references of this selected sample, as shown in Figure  Regarding the main authorship of the articles, 13 (46.4%) were physicians, eight (28.6%) were nurses, two (7.1%) were psychologists, two (7.1%) were occupational therapists, one (3.6%) was a pharmacist, one (3.6%) was a physical educator, and one (3.6%) was a physical therapist.
It was also noted that 15 (53.6%) of the studies were carried out in China, five (17.9%) in Germany, three (10.7%) in the United States, two (7.1%) in Sweden, two (7.1%) in Korea, and one (3.6%) in Thailand. Figure 3, presents the description of the studies analyzed in the SR.

Study
Year Title

E1
2016 Exploratory outcome assessment of Qigong/Tai Chi Easy on breast cancer survivor (13) .

E5 2015
Qigong versus exercise therapy for chronic low back pain in adults: a randomized controlled non-inferiority trial (17) .

E6
2012 Therapeutic Effects of Qigong in Patients with COPD: a Randomized Controlled Trial (18) .

E7 2009
Effects of Qigong in patients with burnout: a randomized controlled trial (19) .

E8 2011
Functional and Psychosocial Effects of Health Qigong in Patients with COPD: a Randomized Controlled Trial (20) .

E9 2016 Effects of Qigong Exercise on Biomarkers and Mental and Physical Health in Adults With at Least One Risk Factor for
Coronary Artery Disease (21) .
Effects of a Brief Qigong-based Stress Reduction Program (BQSRP) in a distressed Korean population: a randomized trial (22) .

E11 2013
Psycho-physical and neurophysiological effects of qigong on depressed elders with chronic illness (23) .

A Randomized Controlled Trial of Qigong Exercise on Fatigue Symptoms, Functioning, and Telomerase Activity in Persons
with Chronic Fatigue or Chronic Fatigue Syndrome (25) .

E14 2011
Tai chi Qigong improves lung functions and activity tolerance in COPD clients: a single blind, randomized controlled trial (26) .

E15
2011 Qigong Versus Exercise Versus No Therapy for Patients With Chronic Neck Pain: a randomized controlled trial (27) .

E16
2010 Qigong for the treatment of tinnitus: a prospective randomized controlled study (28) .

E17 2009
Qigong and exercise therapy for elderly patients with chronic neck pain (QIBANE): a randomized controlled study (29) .

E18 2009
Tai Chi Qigong for the quality of life of patients with knee osteoarthritis: a pilot, randomized, waiting list controlled trial (30) .

E20
2017 Qigong/tai chi for sleep and fatigue in prostate cancer patients undergoing radiotherapy: a randomized controlled trial (32) .

E21
2015 The Effects of a 6-Month Tai Chi Qigong Training Program on Temporomandibular, Cervical, and Shoulder Joint Mobility and Sleep Problems in Nasopharyngeal Cancer Survivors (33) .

2016
A randomized controlled trial of qigong on fatigue and sleep quality for non-Hodgkin's lymphoma patients undergoing chemotherapy (34) .

E23
2013 The sustaining effects of Tai chi Qigong on physiological health for COPD patients: a randomized controlled trial (35) .

E24 2017
Effects of tai chi qigong on psychosocial well-being among hidden elderly, using elderly neighborhood volunteer approach: a pilot randomized controlled trial (36) .

E25 2017
A nurse facilitated mind-body interactive exercise (Chan-Chuang qigong) improves the health status of non-Hodgkin lymphoma patients receiving chemotherapy: Randomised controlled trial (37) .

E26 2017
The efficacy of Guolin-Qigong on the body-mind health of Chinese women with breast cancer: a randomized controlled trial (38) .

E27
2018 Effects of Qigong practice in office workers with chronic non-specific low back pain: a randomized control trial (39) .

E28 2014
Effect of qigong training on fatigue in haemodialysis patients: a non-randomized controlled trial (40) . All the articles submitted for analysis were published in English, and 21 of them were in different journals with a predominance (n = 24) of medical journals. Only one was not randomized, although all were evaluated with level of evidence of II, considered strong, according to the theoretical framework adopted (11) .
The works were critically evaluated, according to However, the salivary cortisol indexes did not change (22) .
E11 (23) , study of Qigong (12 weeks) in depressed elderly people with chronic diseases (n = 38) and with a mean age of 80 years old, revealed that the intervention group showed a significant reduction in the depressive symptoms (p < 0.025), improved self-efficacy (p = 0.050), improved self-concept of physical well-being (p < 0.025), and increased physical strength (p = 0.034). In addition, a lower level of salivary cortisol (p < 0.008) was found in the referred group (23) . that 82% of the participants reported that they would continue the exercises, while nine reported that they extended their friendship circle, which indicates that the majority liked to practice Tai Chi/Qigong (36) .
The third thematic category referred to the analgesic effects related to the practice of Qigong, in which five studies were analyzed (E4, E5, E15, E17 and E27). E4 (16) , conducted with elderly people with low back pain (n = 176) with a mean age of 72 years old, showed no statistically significant distinctions in the groups regarding changes in the degree of low back pain during the survey (Qigong x Yoga, p = 0.18, and Qigong x Control, p = 0.12). However, there was satisfaction with the Qigong therapy (7.9) and Yoga (7.8) and greater chances of recommending it to other individuals (16) .
E15 (27) revealed that Qigong (6 months to conventional exercises (27) . As for E17 (29) , conducted with elderly people presenting chronic pain in the cervical region (n = 93) with a mean age of 75 years old, regarding pain, lack of capacity, and QoL, no significant distinctions were identified when comparing the Qigong (3 months) and control (p = 0.099) groups, as well as those with conventional exercise practices (p = 0.699) (29) .
As for E20 (32) , which evaluated men with prostate cancer (n = 50) undergoing radiotherapy treatment with a mean age of 64 years old, it was noted that the group that practiced Qigong during the treatment described longer nights of sleep (p = 0.05) when compared to the control groups and to those who performed milder activities; however, at the end of radiotherapy, this no longer occurred (32) .
On the other hand, E21 (33) , involving people there is a considerable practice period (34) . In this sense, E25 (37) , conducted with patients affected by the same disease (n = 96) with a mean age of 60 years old and submitted to the first cycle of chemotherapy treatment, also revealed an important improvement in the level of fatigue (p < 0.001) for the intervention group, in addition to white blood cells (p < 0.001), hemoglobin (p = 0.002), and sleep quality (p < 0.001) (37) .
In addition, E2 (38) , conducted with participants rehabilitating from breast cancer (n = 158) with a mean age of 50 years old, there were benefits for emotional (p < 0.01) and specific (p < 0.01) wellbeing with regard to QoL submitted to evaluation and comparison with the control group for Qigong (24 weeks).
There were benefits regarding anxiety (p < 0.01) for the intervention group. The control group had benefits for depression (p < 0.05). However, no significant distinction was identified between them. Both groups showed immunity benefits; however, in the Qigong one, it was more developed in the degrees of tumoral necrosis-alpha (TNF-a) (p < 0.05) compared to the control group (38) .
E6 (18) , conducted with patients with Chronic Obstructive Pulmonary Disease (COPD) (n = 118) with a mean age of 62 years old, revealed that, even without being related to the stage of the disease, both the group that practiced Qigong conventional pulmonary rehabilitation activities improved with respect to the 6-minute walk test and QoL scores when compared to the control group. More precisely, those who practiced Qigong improved in decreasing acute exacerbation of COPD stage I, as well as the related complications, in addition to maintaining the stability of the TNF-a factor level for people with COPD stage II (18) .
As for E7 (19) , conducted with participants with Burnout (n = 68) with a mean age of 44 years old, the results did not obtain statistically relevant distinctions in relation to the groups considered (12 weeks), since both had benefits in reducing the degrees of Burnout, fatigue, anxiety, and depression through Qigong (19) .
Still with COPD participants (n = 52) with a mean age of 73 years, E8 (20) showed evidence for the development of functional capacity and QoL in all of its subscales in the group that practiced Qigong, while the other group showed signs of worsening QoL in four (general health, mental health, fatigue, and emotional) (20) .
Regarding E14 (26) , conducted with individuals with COPD (n = 206) with a mean age of 73 years old, improvements similar to other studies were found in the Qigong group (3 months) with regard to vital capacity (p = 0.002), forced expiratory volume in 1 second (p < 0.001), and exacerbation rate (p = 0.006).
This was not evidenced in the conventional exercise group. Worsening of lung function was noted for the control group (26) .
Therapy was also assessed in E16 (28) , conducted with individuals with tinnitus (n = 71) with a mean age of 45 years old, revealing that Qigong (5 weeks) improved tinnitus (p < 0.0001). Also, it is possible to consider that the intervention is potentially beneficial for the treatment of this condition given the great satisfaction of people with the therapy, as well as the stability of its effects (3 months) (28) . In E18 (30) , conducted with people affected by symptomatic osteoarthritis with radiological changes in the knee joint (n = 44), with a mean age of 69 years old, the therapy showed statistically significant benefits for QoL in relation to the control group (p = 0.010), as well as in the 6-minute walk test (p = 0.005) (30) .
Individuals with Fibromyalgia Syndrome (FMS) (n = 57), with a mean age of 69 years old, were also studied in E19 (31) , with an important decrease in pain (p < 0.0001), in addition to less inconvenience reported due to the condition (p < 0.0001) and better ability to keep it under control (p < 0.01) with therapy. Similarly, the group with people who practiced Qigong (7 weeks) reported a significant decrease in anxiety in relation to the control group (p < 0.01), in addition to a benefit in relation to QoL (p < 0.01) (31) .
Still regarding COPD, E23 (35) , conducted with 206 participants with a mean age of 73 years old, showed an important development of exercise capacity (6 months) (p < 0.001), as well as a significant increase in the mean walking distance (+ 17%). A benefit for pulmonary functions was also identified (p < 0.001), as well as an improvement in the mean forced expiratory volume in 1 s (+ 11%) (35) .
Finally, E28 (40) , conducted with patients undergoing hemodialysis (n = 172) with a mean age of 57 years old, revealed that, for the intervention group (6 months), fatigue was lower after 8 weeks of practice, with a significant decrease compared to the control group (p = 0.005). In addition, the research identified the benefit of Qigong for this audience in terms of strengthening muscles, developing psychological function, and reducing stress (40) .

Discussion
The Several research studies on the subject also indicated improvements in breathing, circulation, relaxation, and functions related to cognition due to the practice of Qigong, similarly to the findings of this study (41)(42)(43) . There was also evidence capable of positively associating the practice with the management of risk factors related to cardiovascular diseases, that is, Qigong is relevant to promote health and prevent illnesses for adults and for the elderly. that adrenocorticotrophic (ACTH) by the hypophysis (47)(48) .
As for analgesic effects, pain was one of the important outcomes investigated by the studies, with the literature showing that the therapy can enhance the level of tolerance and perception of pain, especially in adults. In this way, a relevant endogenous release of pain control is related to the practice of Qigong in the studies (49)(50) . The effects of Qigong with regard to the pituitary-hypothalamus-adrenal axis, play an important role in the pathophysiology of fibromyalgia (49,51) , which makes it relevant to the recommendation and employment in the search for rehabilitating adults and the elderly.
As for Parkinson's disease, studies in the area are in line with the results presented in this SR, proving that regular exercise practice, as proposed by Qigong, is beneficial for the rehabilitation of these patients, as it brings physical benefits, as well as a reduced chance that elderly people will suffer falls (52) .
With regard to the effects on oncology, a prospective longitudinal research has shown that it is even possible to consider the practice, inserted in the lifestyle, as protective with regard to the reduction of deaths due to neoplasms, by stimulating the immune system and controlling the inflammatory response related to the disease (53) .
It is also noted, in the research considered, an increase in the duration and intensity of the positive results of Qigong, proportional to the quantity practiced. This, therefore, needs to be considered to recommend engaging in research studies that aim to investigate the results of this practice for health. Therefore, an intervention protocol of at least four weeks is recommended, based on the results found in this SR.
Qigong is based on the development of selfknowledge, making its practitioner active and capable of preventing and curing diseases throughout life. Thus, Qigong is shown as a mind-body exercise modality that can be easily practiced by adults and very beneficial in the long term, as shown in the results of this study.
Through the critical evaluation conducted, it was possible to verify a high risk of bias in the research blinding domains, since this was impossible, and there was a probability of influencing the evaluation of the results, which lacked adequate control or, therefore, a clear description of the protocol and analysis (54) .
It is recommended to carry out new randomized clinical trials with a high level of methodology focusing on this research subject. In addition, in order to assess the practice of Qigong, longitudinal research studies involving healthy people are necessary to compose the baseline.

Conclusion
It is possible to understand the physiological results from the practice of Qigong through the scientific evidence identified and submitted to evaluation, which makes this study of great contribution, since it brings a synthesis of the production regarding the use of an integrative and complementary practice in health, based on the most relevant scientific findings available.
The SR revealed the beneficial application of Qigong in the promotion, prevention, and rehabilitation of diseases and physiological disorders in adults and