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Reiki as nursing care to people in mental suffering : an integrative review

e20200458 http://dx.doi.org/10.1590/0034-7167-2020-0458 8 of ABSTRACT Objective: To analyze the scientific evidences of the use of Reiki as a care strategy to people in mental suffering. Methods: Integrative review in the databases PubMed, Scielo, Web of Science, and BVS. The study included articles in English, Portuguese, and Spanish, with no time restriction, which answer to the guiding question that was created in accordance to the PICo strategy: “What are the scientific evidences on the use of Reiki as a care strategy to people in mental suffering?” Gray literature was not considered. Results: Ten articles made up the final sample. The use of the Reiki therapy had benefits as a strategy to care for stress, anxiety, depressive symptoms, pain relief, and quality of life improvements, whether the therapy was used isolated or to complement other treatments. Conclusion: The development of the competence of nurses and other health professionals in the use of Reiki can contribute to improve the quality standards of care. Descriptors: Mental Suffering; Holistic Therapy; Therapeutic Touch; Nursing Care; Review.


INTRODUCTION
Mental disorders affect at least 450 million people around the world, and is responsible, in the Americas, for one third of the total number of psychic disabilities that prevent work (1)(2) .
Mental disorders are social phenomena, seen by many according to the culture of each era. However, despite advances, it is still not possible to reach a consensual definition of mental health problems, which, depending on the theoretical references adopted, can also me called mental disorders, mental suffering, and mental suffering (3) . For this integrative review, we chose to use the term "pessoas em sofrimento psíquico" (people in mental suffering), since these terms are in line to the postulates of the mental health policy established in Brazil (4) .
Mental suffering is a health problem with a high index of morbidity in contemporary society, and is considered to be an important public health issue (5) .
In Brazil, studies found a prevalence varying from 20% to 56% of adults in mental suffering, including mood disorders, somatic symptom disorder, alcohol abuse, and anxiety (6) . The latter, in particular, is considered to be epidemic, with a prevalence of 9.3%; this number means that the country is the first, considering South America, in psychic disabilities caused by this disorder (2) .
People in mental suffering present high levels of functional disability, with impairment in daily activities, work, and social relations (7) . The disability associated to psychic sufferings leads to social and economic impairments, reverberating in the way in which health care services are organized (8) . Despite the fact that many countries have changed their mental health policies, there is more demand than supply of services, and there is a high percentage of adults and children, especially in native/indigenous populations, with severe mental disorders that go untreated (2) .
Psychic suffering may be associated to clinical comorbidities such as metabolic, cardiovascular, or endocrine disorders, cancer and HIV/AIDS (9)(10)(11) , leading to repercussions in health care, family, health managers, and user rehabilitation (12) .
The traditional model of treatment to these health problems is focused on the prescription of psychiatric drugs and psychotherapies (13) . However, it is necessary to search for other health care options that are effective for people in mental suffering, minimizing the collateral effects and attending to the needs of this group of clients.
An alternative to the traditional model focused on the use of psychiatric drugs are Complementary and Integrative Practices (PICs), implemented in Brazil by the National Policy of Complementary and Integrative Practices (PNPIC) (14) . The PICs are resources that have been increasingly used, since they promote humane care, focused on the client, in addition to aiding in the process of health recovery, respecting and giving support to the preexisting therapeutic care (15) .
Among the PICs offered in the scope of health care, we can highlight Reiki as a therapeutic practice that uses the laying on of hands to channel vital energy, seeking to promote the energetic balance that is necessary to physical and mental wellbeing (16) .
Some researches point out that the Reiki therapy can contribute in the care to people in mental suffering, diminishing the levels of anxiety and depression (17) , relaxation and stress management (18) , as well as reducing burnout (19) . Its use brings new possibilities to care in a simple, safe, and non-invasive manner, since it is considered to be a low-risk intervention that is used among the many professionals who work in the hospital sectors and in Primary Care (20)(21) .
Among the professions in the field of health, nursing is defined as the profession of direct, effective, and holistic care. As a result, the therapeutic touch offers the possibility of changing day to day care even more, that is, of transforming the experience of the patient through an embracing, pleasant, and unique experience, developing a therapeutic relationship through the creation of bonds and confidence (22) .
Thus, Reiki presents itself to nurses as a specialized practice of care, regulated in Brazil according to a Decree from the National Council of Nursing (COFEN) 581/2018 (23) .
Previous studies (24)(25) have reviewed literature in order to verify how Reiki contributed in the many settings of care. Nevertheless, the sources researched still have few publications that studied this practice as a therapy in the care of people in mental suffering. Finding more about the use of this therapy to this end, nurses will be able to give it scientific support, using it in their daily practices.

OBJECTIVE
To analyze scientific evidences of the use of Reiki as a care strategy to people in mental suffering.

METHODS
This is an integrative review following the model proposed by Whittemore and Knafl: 1) identification of the team or question of the integrative review; 2) sampling or literature search; 3) evaluation and categorization of the studies included in the integrative review; 4) data analysis; and 5) summary of the knowledge shown in the articles analyzed, or presentation of the integrative review (26) .
To elaborate the research question, an adaptation of the PICO strategy (Patient, Intervention, Comparison, and Outcomes) was used, since not all elements of the strategy apply to the choice of the question of this review (27) . In this integrative review, the third and fourth elements were substituted by "context", and then the strategy PICo (Problem/Population, Interest and Context) was employed.
As a result, the guiding question of the review was elaborated considering: (P) -person in mental suffering; (I) -use of Reiki; and (Co) -use of Reiki as a strategy of care. Finally, the following guiding question was defined: "What are the scientific evidences about the use of Reiki as a health care strategy to the person in mental suffering?".
A literature search was carried out through the databases PubMed, SciELO, Web of Science, and BVS, in October 2019, regardless of year of publication and using the language filters for Portuguese, English, and Spanish. Only articles whose full text was available were considered. The research used indexed descriptors, namely "Mental Disorders", "Holistic Therapies", and "Therapeutic Touch", with the aid of the boolean operators AND and OR. The same search strategy was used in all databases "Mental Disorders"AND ("Therapeutic Touch" OR "Holistic Therapies").
Inclusion criteria included original articles, in Portuguese, English, and Spanish, which highlighted Reiki as a health care strategy for people undergoing psychic suffering, according to the guiding question of the research. The criteria of exclusion adopted included: theses, dissertations, books or book chapters, editorials, newspaper articles, integrative or systematic reviews, case studies, experience reports of articles describing experiments that did not involve human beings. Other details are in Figure 1.
qualitative studies, weak evidence; Level VI -Evidences derived from a single descriptive or qualitative study; Level VII -Opinion of authorities or report from specialist committees. In the fifth stage, regarding the interpretation of results, the following were extracted from the articles: target-population, instrument used to evaluate mental suffering, type of mental suffering, protocol for the use of Reiki, and therapies used in association with Reiki as a research outcome.

RESULTS
The final sample was made up by ten studies, published from 2004 to 2017 (Chart 1). The articles selected came from four countries: the United States (6), the United Kingdom (2), Brazil (1), and Italy (1).
It stands out that all articles presented, as their target population, adults with some degree of psychic suffering. Although the author of an article (37) selected a sample with "healthy" participants, after the scale was applied, most of them were found to have an anxiety score.
Regarding the instruments to measure the effects of the Reiki technique in the participants of the study, the most common ones were: Spielberg Anxiety Inventory (33,35) , Visual Analog Scales (VAS) for Pain and Anxiety (31,35) , Perceived Stress Scale (PSS) ( 32,40) , Depression, Anxiety, and Stress Scale (DASS), Pittsburgh Quality of Sleep Index (PSQI), Illness Symptoms Questionnaire, Activation Deactivation Adjective Check List (AD-ACL), Reiki-Blinding and Expectation Questionnaire and Illness Symptoms Questionnaire (ISQ) (37)(38) .
Concerning the protocol to carry out Reiki, only one study used the self-application of the technique (32) . The other employed Reiki sessions with therapists graduated in its several levels and adequately certified. The length of the sessions varied from 10 minutes to one hour and a half. The most common interval between sessions was one week, and the mean number of sessions was six.
For the third stage, study categorization, a validated instrument (29) was used to verify the following variables: year, authors, database and country in which the research was carried out, level of evidence, objective, outcomes, and main conclusion of the studies.
The evaluation of the studies included in the review was the fourth stage of the study and was carried out according to the level of evidence proposed by Fineout-Overholt et al. (30) , which establishes six categories: Level I -Evidences from systematic reviews or meta-analyses of relevant clinical essays; Level II -Evidences derived from at least one control and well-designed randomized clinical trial, moderate evidence; Level III -Well designed nonrandomized clinical trials; Level IV -Well designed cohort studies and case studies; Level V -Systematic review of descriptive and

DISCUSSION
From the ten articles analyzed, the United States of America (USA) has the highest number of publications, followed by United Kingdom, Italy, and Brazil. The predominance of NorthAmericans is justified by their growing interest in complementary and alternative medicine (CAM), which encourages researches in this field, especially after the creation of the National Center of Complementary and Alternative Medicine (NCCAM) (41) . In Brazil, although Reiki is part of the list of Complementary and Integrative Practices, integrated to the Single Health System (16) and its wide acceptance in the national setting, there are still few researches about this therapy.
After the articles were reviewed, a great preoccupation can be seen in the scientific community with regard to the criteria adopted by researchers to evaluate the effect/efficacy of the Reiki therapy in the several settings of care in different populations. These weaknesses or methodological biases include: method, sample size, sampling criteria, diversified use of evaluation instruments and protocols to apply the Reiki technique (24,31,33) . Regarding their methodological approach, all articles used quantitative data to measure the effect of the Reiki therapy. However, six publications added qualitative data in their studies (31)(32)(33)(35)(36)39) .
In the scientific field, there is no consensus with regard to the best research method for the analysis of energetic therapies, with some authors questioning the way in which studies measure the efficacy of the laying on of hands, not considering the individual experience of participants, and the use of random analysis models that are the same ones applied to drugs, considered to be the "golden-standard" in medical research (24) .
In this review, a study presented, as a limitation, the fact that they did not evaluate the motivation of the participant in seeking the Reiki therapy (34) ; other researchers suggest qualitative researches or mixed methods to better understand the experience of the Reiki therapy from the perspective of the participants in the research (24,33,35) and its benefits (39) . However, other works recommended the use of controlled and randomized studies to confirm the efficacy of this practice (32,37) .
Regarding their population, all studies use the Reiki therapy in adults, which can be confirmed in the researches carried out in the databases for this review.
In the works selected, there is an evident diversity of instruments used to evaluate the results, considering wellbeing, quality of life, pain, depression, and anxiety. Despite the reliability and validity of these instruments, the results found presented differences that may be related to the conformance of these instruments to the object of the research, thus leading to a methodological bias (24) .
As a result, it can be inferred that, when working with subjective variables such as the ones described above, it is necessary to conceive differently the health/disease processes and the theoretical/technical means to care for people under mental suffering.
The lack of standardization of the protocols used to apply the Reiki intervention was evident in the studies included in this review. This heterogeneity is related to the type, frequency, duration of the practice, and experience level of the professional (42) . Two studies used, as a methodological approach, the clinical trial and the methodological rigor during the application of Reiki. However, practitioners used Reiki techniques and symbols intuitively, to attend to the individual needs of each participant (37)(38) .
The level of experience of the therapist may be a methodological bias, since the effectiveness of the technique of laying on hands may be related to it (24) . However, the self-application of Reiki by nurses who have received 21 days of training in the technique was capable of diminishing levels of stress related to work (32) .
The diversity in the protocols can be explained by the several teaching methods used by Reiki masters. The complexity in the research of this therapy is evident, with authors that suggest more creative approaches, such as the use of bioelectrography before and after treatment sessions to measure the results of the energetic work (33) , as well as individual treatments that consider the subjectivities and needs of the patient (24) .
The Reiki therapy, as a strategy of care to the person under psychic suffering, showed benefits in dealing with stress, anxiety, and depression, be it in the occupational context, where it improved the mood of university students with anxiety and/or depression (37)(38) , be it in the occupational scope, in which nurses that adopted Reiki as a self-care tool showed reduction in the levels of work-related stress (32) .
In the case of chronic diseases, with a strong load of mental suffering, related to invasive procedures, the prolonged use of medication, the stigma and the feeling of being finite, the use of the therapy contributes to manage the pain, the stress, as well as anxiety and depression (43)(44) . A study has shown that the use of Reiki in association to music helped diminishing these disorders in people with HIV (35) .
Furthermore, this technique is considered to be relaxing and has no side effects, offering wellbeing, pain relief, improving in the quality of sleep and diminishing anxiety in patients who undergo chemotherapy (31,36) . Therefore, Reiki reestablishes adequate energetic levels for a balance between mind, body, and emotions, and is seen as a non-pharmacological nursing care strategy (45) .
According to Watson's nursing theory, the spiritual dimension is part of the transpersonal care model (46) . The constructs established by this theoretical milestone reflect the relations between nurse and patient, which are permeated by: presence, personal development, acceptance of the unknown, and trust. This model also states that hope can transform both the nurse and the person cared for. These ideas are reinforced by energetic therapies one of which is Reiki, which seek to give a stronger feeling of spiritual consciousness to the parties involved (47) .
The complexity and the subjectivity of the factors involved in the care of people who undergo psychic suffering demand the actions of an interdisciplinary team in many levels of attention, and nurses, as part of said team, can contribute with technical knowledge and abilities inherent to their education, in addition to further therapeutic practices that can be added to daily care, such as Reiki.
In this context, Reiki was found to be a promising tool when inserted in the practice of the interdisciplinary team through professionals introduced and certified in the practice (39) . As a result, it can be understood as a therapeutic resource, which is still seldom used by psychiatric nursing, but whose clinical involvement is expanding (33) .
Furthermore, through the analysis of scientific evidences about the use of Reiki, it can be understood as an innovative technology of care, which is of low cost and can be used by nurses and other professionals that promote mental health, with previous training, in situations of mental suffering. This is because the energy that flows through the hands of the practitioner can harmonize the individual according to their needs and, as a result, can promote physical, mental, and emotional balance, improving their quality of life.

Study limitations
The limitations of this study include the small number of studies found in the searches in databases. This may be due to the number of databases chosen for the research, their language, and the exclusion of gray literature. As an attempt to reduce the effect of this limitation, the search strategy used broad terms and did not restrict studies with regard to the year of publication, seeking to reach a higher number of results. However, the scarcity of works on the theme may also be attributed to the fact that these complementary and integrative practices to mental health care are a novelty. 8 of Reiki as nursing care to people in mental suffering: an integrative review Santos CMR, Crispim MO, Silva TTM, Souza RCR, Frazão CMFQ, Frazão IS.

Contributions to the fields of Nursing, Health or Public Policy
This research can contribute to give substance to proposals of action in mental health care in the field of Nursing, through the publication and summary of scientific evidences for the use of complementary and integrative practices, among which Reiki. Thus, it can empower nurses and multiprofessional teams; seek holistic and humane attention; and attend to the uniqueness of people under mental suffering, in accordance to the prescriptions of the Brazilian Psychiatric Reform.
Consequently, the collection, analysis, and integration of the findings within a global meaning may encourage the creation of Unique Therapeutic Projects and the development of new researches that involve nursing care and multidisciplinary teams, based on non-pharmacological strategies to treat mental disorders in the multiple settings of health care.

CONCLUSIONS
Through the results of the articles analyzed, this study shows that Reiki, as a practice applied to the relief of pain and psychic suffering by nurses or by other members of the multidisciplinary team of health care contributes for the improvement of quality standards in assistance, since it humanizes the care provided.
It was noteworthy that scientific evidences are still scarce in the databases analyzed with regard to the use of Reiki for people in mental suffering, but their number is growing. Therefore, future researches must be carried out to enhance the production of knowledge about this technique, as an instrument of care in mental health.
Additionally, the results have shown that the use of the Reiki therapy presented benefits for people under psychic suffering, such as reducing stress, anxiety, depression symptoms, and physical pain. Both in isolation and when together with another type of treatment, this therapy has also been used for relaxation, aiding in the improvement of quality of life.
However, questions have been raised with regard to the scientific evidences found about the methodologies used to evaluate the efficacy of energetic therapies. Some authors recommended qualitative or mixed-method evaluative studies, believing that quantitative researches do not reveal subtle changes in vibration.