Received 22 April 2015, revised 19 January 2016

Transcription

1 Indian Journal of Traditional Knowledge Vol. 15(3), July 2016, pp Traditional knowledge on benefits of yoga practice verified in modern scientific literature: An overview of journals indexed in Integrative and Complementary Medicine Zorica Popović 1 *& Predrag Nikić 2 1 Institute for Biological Research, University of Belgrade, BulevardespotaStefana 142, Belgrade, Republic of Serbia; 2 Faculty of Commerce and Banking, University Alpha, Palmira Toljatija 3, Belgrade, Republic of Serbia zorica.popovic@ibiss.bg.ac.rs Received 22 April 2015, revised 19 January 2016 A total of 195 papers regarding yoga, published from 2001 to 2014 in from 24 journals indexed in Integrative and Complementary medicine, were extracted from the science citation index (SCI). The most productive journals were: Evidence-Based Complementary and Alternative Medicine, Journal of Alternative and Complementary Medicine, Alternative Therapies in Health and Medicine, Complementary Therapies in Medicine and BMC Complementary and Alternative Medicine, in which the cumulative number of papers on this subject constantly increased. The authors from US attained the dominant position regarding research on yoga practice and theory, followed by Indian, Australian, German and authors from UK. Most of research was conducted by the authors from the same country, less were the result of international collaboration. In total number of papers, reviews accounted with 38 titles, and original research with 157. The greatest interest was in publishing results of clinical experiments, particularly RTC studies (randomized controlled trials). Abstract analysis showed a variety of experimental designs, duration of research, subject categories, yoga techniques and reliability of conclusions derived. This paper gives an insight of current status of yoga research within the subject area Integrative and Complementary Medicine, showing the significant number of RTC studies and a great number of pilot and prospective studies with tendency to be expanded to RTC trials. All presented results indicate scientific recognition of yoga as a complementary medicinal practice and its incorporation in integrative medicinal approaches. Keywords: Integrative and complementary medicine, Yoga, Abstract analysis, Bibliometry IPC Int. Cl. 8 : A01D 23/03, A01D 11/17, A61B 5/00, A61B 17/42, A62, A62B Yoga is a comprehensive mind-body discipline comprising a wide variety of mental, spiritual and physical practices in order to achieve inner harmony, mental and physical health and consequently a union of the human individual with the universal and transcendent Existence 1. Approximately between the 8 th century BC, yoga occurs in the Upanishads and in the Bhagavad-gita 2. At the beginning of the new era, i.e., the 2 nd century, mature concept of yoga is being presented in the section Quotes about Yoga in Patanjali 3. The period around 7 th century is related to the recent Upanishads, Asparsha, Dhyana, Hatha and Kundalini yoga. Holistic system of yoga, its various methods and techniques (kriya, bandha, mudra, asana, pranayama, prathyahara, dharana, dhyana) implemented to achieve the higher states of consciousness, purpose of meaning and freedom, *Corresponding author consequently improved the psycho-physical state of practitioners. Most of authors agree that the primary goal of yoga practice is spiritual development, and positive effects to human health are considered as additional benefit Recognition of yoga as a therapeutic method in modern medicine has started along with the pioneering scientific research on yoga by Swami Kuvalayananda ( ) who published first experimental research on physiological effect of asanas, pranayama and meditation in western biomedical terms 11. Popularization of yoga as a powerful technique for preserving and improving the health continued through the great influence of Indian teachers, Tirumalai Krishnamacharaya ( ), BK SIyengar ( ) and TKV Desikachar (1938-), who emphasized the potential benefits of yoga, compatible with biomedical science Incorporation of yoga in modern medicinal practice is

2 POPOVIĆ & NIKIĆ: TRADITION OF YOGA AS COMPLEMENTARY MEDICINE 379 clearly summarized in the comprehensive review given by Khalsa 15, which describes first steps of systematic medical application of yoga in India in 1918 and 1920 s, followed by establishment of yogic clinics such as the Swami Vivekananda Yoga Research Institute and other similar institutions. International acceptance of this trend resulted in formation of yoga therapy centers, integration of yoga in hospital programs, professional trainings of staff for yoga therapy, Associations of Yoga Therapists (International, American, European, etc.). Publication of professional and scientific literature has made knowledge in this field widely available. Recent bibliometric analysis of available databases demonstrated continuous increase of published randomized controlled yoga trials over the long time period ( ) 16. By searching a number of databases (Scopus, Medline/PubMed, Google Scholar, Proquest, Web of Science) for publications regarding yoga during the period , we found a large number of titles (4004 documents related to the search term yoga ) published in numerous journals (159), with the increasing trend of scientific interest in this area ( : 631, : 1258, : 2006 ). Among a variety of journals and subject areas generating interest in publication titles regarding yoga practice and theory, the largest number of titles (49.9%) was published in journals indexed for subject area Medicine: Complementary and Alternative Medicine(CAM) (Web of Science Thomson Reuters classification). The purpose of our study was to extract research (original research, reviews and short communications) regarding yoga from journals indexed in subject area Integrative and Complementary Medicine (I & C Medicine) and evaluate the position and research trends of this indigenous health promoting and healing practice at the beginning of the 21 st century. Materials and methods The material includes published between January 1, 2001 and December 31, 2014 in scientific journals indexed in the subject area Integrative and Complementary Medicine (Thomson Reuters), i.e., 24 journals accessed through the portal of the Serbian Library Consortium for Coordinated Acquisition (KoBSON), hosted by the Center for Scientific Information at the National Library of Serbia. All searches were conducted using the keyword yoga and were limited to original, reviews and short communications. Authors of this study are scientists experienced in bio-medicinal and humanities and social sciences, at the same time oriented to research within the area of yoga through International Society for Multidisciplinary Yoga Research and International Yoga Academy. Every abstract was carefully read in order to secure that one of the main topics is related to yoga practice or theory. In total, 195 were analyzed. All of them had titles and abstracts in English. Document information including titles, years of publications, source journal, number of authors and their origin country for each article were downloaded. Additional coding for each article was performed for type of article (Original research article or Review, since Short communications were not detected), type of study (Experimental or Theoretic), area of research (Medicinal study, Bibliometric study, Sociology & economy study), sampling strategy (Randomized Controlled Study, Pilot Study, Prospective study, other), subject population (health status/disease treated). Considering that the conclusions on the effect of treatment in many original research were descriptive, we decided to apply a numerological valorization according to 0-5 scale, where 0 means that there was not statistical evaluation of obtained data (it was concluded that treatment may be helpful, evidence is not clear, may have benefit ), 1 means that treatment has no statistically significant effects, 2 means small positive effects, 3 means moderate changes in measured outcomes, 4 is for beneficial effects in specific clinical outcomes, 5 means that yoga treatment was effective intervention for specific medical condition. When we came to reviews, it was clear that the authors have already excluded of questionable methodological approach, and mostly considered RTC, so we classified their conclusions on 1-3 scale, where1 means small positive change, 2 moderate benefits and 3 effective method. Microsoft Excel 2010 was used for creating a unifying database and Statistica 8.0 program (StatSoftinc. 2007) for running descriptive analyses. Results Based on described search method, a total of 195 were identified among the journals indexed in I&C Medicine subject area. In the studied 14 yrs period, the number of on yoga in I&C Medicine increased from 0 (1) in 2001 (2002) to 51

3 380 INDIAN J TRADIT KNOWLE, VOL 15, NO. 3, JULY 2016 (2014), and can be graphically plotted through the curve of exponential growth (Fig. 1). The top 4 journals published more than 50% of these, as presented in Fig. 2. The journal, Evidence-Based Complementary and Alternative Medicine published the largest number of yoga related (48, 20.5% of the total), followed by Journal of Alternative and Complementary Medicine (46, 23.6%), Alternative Therapies in Health and Medicine (27, 13.8%), Complementary Therapies in Medicine (24, 12.3%) and BMC Complementary and Alternative Medicine Fig.1 Number of related to yoga from 2001 to 2014 in journals indexed in I&C Medicine, exponential and linear fitting (19, 9.7%). Journals, Holistic Nursing Practice and Explore and The Journal of Science and Healing had more or less constant (small) number of regarding yoga from year to year (10 and 8, respectively). Other five journals (Integrative Cancer Therapies, Forschende Komplementarmedizin, Chinese Journal of Alternative Medicine, African Journal of Traditional, Complementary and Alternative Medicine, Alternative Medicine Review) sporadically published such, once or twice during the investigated period. The authors from United States were the most productive (53.3%), followed by authors from India (11.8%), Australia (7.2%), Germany (6.7%) and United Kingdom (3.6%). Three came from Brazil, China and Turkey, and each country participated in whole publication sum with 1.6%. Authors from other countries published two (Iran, New Zealand, Slovenia, Sweden, Taiwan) or one article (Iceland, Italy, Japan, Netherlands, Pakistan, Russian Federation, Singapore, South Korea, Thailand). The great majority of studies have been conducted as the project from single country (88.7%), and much lesser number was the result of international collaboration, 9.2% from two countries and 2.1% from three countries. Fig.2 Dynamics of publication related to yoga in 12 journals from 2001 to 2014.

4 POPOVIĆ & NIKIĆ: TRADITION OF YOGA AS COMPLEMENTARY MEDICINE 381 The largest number of studies was from the area of Medicine (135), e.g. randomized controlled trials, prospective and pilot studies. Number of publications classified by article type, study type, area of research, and experimental design (only of medicinal studies) are presented in Table 1. By analyzing reviews, we found that authors processed different number of studies related to subject, depending on number and availability of from particular area. Thus, number of studies analyzed in reviews ranged from 10 to 152, two reviews were aimed at comparing concepts, and one was narrative review. After analysis of original research, we found different concepts in experimental design regarding subject groups (Table 2). Based on different criteria, 11 subject groups of participants could be recognized, and the largest number of report results obtained from participants with certain health problems (66.5%). Also, different styles of yoga were applied in order to study their effectiveness, 11 in total (Table 3, the last five listed in table are not recognized as official styles by International Yoga Federation), while the largest number of present results obtained with non-specified yoga styles (73.8%). Yoga classes were performed for varying durations, usually from 8 weeks, through 3-6 months, to 2 yrs. Few studies report effects of long time yoga practice, 10 and 11 yrs, respectively. Usually, there were 1-2 yoga classes weekly, and they were carried out as group or home/individual classes. Table 2 Number of presenting various subject groups that underwent investigation (by different criteria: health status, age, sex, profession). Criteria Subject group No of ailment/medicinal participants/individuals 53 condition medicinal condition + female 25 gender medicinal condition + male 5 gender health status healthy 19 individuals/volunteers age group children 6 age group adolescent 4 age group students 1 age group senior population 10 profession yoga instructors + 9 practitioners profession employees 3 profession professional musicians 1 Table 1 Number of publications classified by article type, study type, area of research and experimental design (only studies in Medicine). Type of article No (%) Type of study No(%) Area of research No(%) Experimental design Original research article 157 (80.5%) Experimental 144 (91.7%) Medicinal study 135 (93.75%) RTC Pilot study Prospective study Case study Cross-sectional analysis Quasi-experimental study Parallel-groups design Waiting-list CT Sociology & economy 6 (4.17%) Methodology of research 2 (1.39%) Bibliometric study 1(0.7%) Theoretic 13(8.3%) Theoretic 10 (71.4%) Sociology & economy 2 (14.3%) Methodology of research 1 (7.14%) - - Review 38 (19.5%) Theoretic 38 (100%) Systematic review 36 (94.7%) Meta-analysis Narrative review Conceptual synthesis Sociology & economy 1(2.6%) Methodology of research 1(2.6%) - - Percentage is recalculated as following: for type of study in regard to type or article; for area of research in regard to type of study. No

5 382 INDIAN J TRADIT KNOWLE, VOL 15, NO. 3, JULY 2016 The largest number of studies investigated effects of yoga to breast cancer and other types of cancer (14 + 3). Other studies showed effects of yoga on chronic low back pain (12), hypertension and blood pressure (10), stress related symptoms and diagnoses (10), depression and anxiety (9), musculoskeletal conditions (6), type II diabetes (6), menopause (6), osteoarthritis (5) and addiction to alcohol, drugs and smoking (5). Smaller number of studies demonstrated effects of yoga to chronic obstructive pulmonary disease (3), cardiovascular disease risk (3), asthma (2), pain (2), restless leg syndrome (2), energy expenditure (2), heart rate response (2), multiple sclerosis (2), and hormonal status (2). A number of various ailments/conditions (35) were studied in a single article, which makes that total list of how tested medical conditions respond to yoga include 54 different items (the number obtained is a summation of abovementioned medical conditions examined in more than one article and those that have been studied only in a single article). In addition, 8 presented results of the effect of yoga on psychological or physiological outcomes (cognitive functioning, strength, well-being, interpersonal relationships, etc.) in subjects where a medical condition was not specified. When considering the effectiveness of the treatment applied, we come to great diversity in the Table 3 Number of presenting investigations on different styles of yoga (only yoga indicates that style or procedure is not specified) Yoga style Application method No of Yoga Yoga classes 112 Yoga Yoga classes + additional 10 treatment Yoga Particular yoga postures 5 Yoga Yoga breathing and/or 4 relaxation Hatha yoga Hatha yoga classes 16 Hatha yoga Particular hatha yoga 1 postures Hatha yoga Hatha yoga classes + 2 additional treatment 3 or more yoga Hatha, Iyengar, Tibetan, 4 styles Raja yoga classes Iyengar yoga Yoga classes 14 Chair yoga Yoga classes 3 Bikram yoga Yoga classes 1 Kripalu yoga Yoga classes 1 Viniyoga Yoga classes 1 Laughter yoga Yoga classes 1 interpretation of results, ranging from the generic, sometimes speculative conclusions, to clearly evidenced and defined proposals about the usage of yoga for specific medical conditions. These observations are presented in Table 4, where 0-5 numerical scale is given for better insight in research outcomes and clearer presentation of results. Most ended with conclusions ranging from moderate positive changes to benefits for specific clinical outcomes (59, 43.7%), and certain number of stated with clinically meaningful results (23, 17.04%). Small, but statistically significant positive effect was the result of 16 studies (11.85%). Articles with no statistically significant differences between yoga treatment and control group were rare (9, 6.67%), but those with speculative and unclear conclusions were found (28, 20.74%). Following the same principle, we analyzed 38 reviews. Authors concluded that yoga therapy applied for particular medical conditions showed its efficiency through small positive changes (13), moderate benefits (20) or was evaluated as an effective method (5) (Table 5). Discussion Research related to yoga as complementary and/or alternative intervention to medicine gained increased Table 4 Effectiveness of treatment applied based on conclusions given by authors (original research, medicinal studies, 135 in total). Numerical valorization of effectiveness Number or Percentage (%) : no statistical evaluation of obtained data; 1: no statistically significant effects; 2: small positive effects; 3: moderate changes in measured outcomes; 4: beneficial effects in specific clinical outcomes; 5: effective for specific medical condition. Table 5 Conclusions given by authors on effectiveness of treatment applied (reviews, 38 in total). Numerical valorization of effectiveness Number or Percentage (%) small positive change; 2 moderate benefits; 3 effective methodsb m

6 POPOVIĆ & NIKIĆ: TRADITION OF YOGA AS COMPLEMENTARY MEDICINE 383 attention in the 21 st century simultaneously with increasing interest for other CAM methodologies and their incorporation into the concept of integrative medicine. In the 195 studies related to yoga, published in journals indexed in I&C Medicine over the first 14 yrs of the 21 st century, we found a great variety of medical conditions treated, different methodologies were applied; also, results on effectiveness of yoga therapy were widely ranged from non-effective to significantly effective in treating the particular medical condition. A large number of ailments were treated with yoga therapy in analyzed in this study. In all, the response of 54 different medical conditions was recorded and several studies reported psychological and physiological outcomes of yoga therapy in healthy subjects. Results of this review related to limitations of the large number of studies, such as small study populations, lack of randomization, lack of control group, and short intervention duration, are similar to that presented by authors of previous reviews. Minimal investment and simplicity of implementation make the application of yoga therapy readily-available in every medical center; due to this most authors evaluated it as a feasible and acceptable intervention. On the other hand, no study recorded adverse or side effects of yoga therapy. In fact, general authors comments highlighted the safeness of yoga treatment. In many cases, it was an acceptable alternative to exercise in cases when physical activity was not suitable 17. It is well known that practicing asanas brings the body to a better level of functioning, by stretching and strengthening different parts of the body, massaging and bringing fresh blood to the internal organs while rejuvenating the nervous system and lubricating the joints, muscles and ligaments 18. Overall, functional response of the body is a psycho physiological response 15,19 and consists of a generalized reduction in both cognitive and somatic arousal, measurable through the modified activity of the hypothalamic and the autonomic nervous system functioning 20. Most authors noted in the introductory section of their that yoga consists of 8limbs, according to Patanjali s original interpretation from second century BC 21. However, medical/therapeutic aspect was investigated by applying one of them (asanas), possibly two (asanas+ breathing or meditation), rarely three (asanas+breathing+meditation). The positive impact of yoga on health has been known for a long time; it has been recommended for practice in the ancient Hindu texts (Upanishads or Vedanta) ( BC). However, it is necessary to undergo thorough investigation and evaluation before gaining a place in modern medical literature and in order for it to become medically valorized. The beginning of this process was launched in 1980s, when Dean Ornish, MD, a medical researcher taught by Swami Satchidananda, linked hatha yoga to healthy lifestyle and heart health, setting up hatha yoga as a purely physical system of health exercises without any religious or spiritual determinants 22. Although a large list of was discussed in this review, literature that was not included here indicates that physical postures have been the dominant part of yoga tradition that has been practiced and used for therapeutic purposes. However, considering that the majority of authors refer to other aspects of yoga tradition, some of them include it as lifestyle (yama, nyama), meditation, breathing, it may be concluded that, after a century of medicalisation, yoga refers back to its comprehensive approach. Yoga means unity, remaining balanced when perceiving dualities; yoga offers its own methods for connecting to the unit. Bearing in mind that yoga is a kind of ability that creates a balance between the physical, emotional and cognitive abilities 23, the concept of yoga can also be perceived as a form of intelligence 24. Increasing interest in yoga therapy is revealed in emerging trend in publications on the subject. With regard to implementation of yoga therapy, this interest results in opening more educational associations for yoga therapists/energotherapists all over the world. Yoga therapeutic method relies on thousands of years of philosophy and practice of deriving a healthy lifestyle that includes people returning to human values, purpose and context 25.It has a comprehensive system of diagnostics, understanding and dissolving the problems in human health (Table 6). Based on results presented here and expected interest for usage of more than one yoga method (asanas) with the purpose of prevention, diagnosis and treatment, i.e., for maintaining health, we assume that scientific research in this area will further increase. This is particularly evident from the conclusions of reviewed that the effects of yoga practice were much broader than the framework of conducted studies. This study revealed the emerging trend in publication of regarding yoga and the most productive journals. Among the several types of trials, quantitatively the studies are dominated by clinical trials. Our work has provided

7 384 INDIAN J TRADIT KNOWLE, VOL 15, NO. 3, JULY 2016 Table 6 Comparison of two approaches: yoga therapy and modern medicine Approach Yoga therapy/energotherapy Modern medicine Cause of the disease (Etiological factor) Klesha Endogenous: disposition, heritage, gender, age; Exogenous: physical, chemical, biological, sociological Mechanism of disease Disorder in prana (energy) flow Pathophysiological processes on cellular level Manifestation of the disease Manifestation on the physical level signs and symptoms of the disorder Manifestation on the affected organ and throughout the body systemic and local symptoms of disease Diagnostic Auxiliary methods: diagnostic by pulse, tongue, eye, energy diagnostic Disease history, clinical examination, radiography, laboratory analyses Therapy Integrative approach Partial approach the evidence of scientific recognition of yoga as a complementary medical practice. More evidencebased and rational therapies based on yoga practice increase the need to develop suitable standardization for particular therapies. It is clear that at the beginning of the 21 st century, by crossing the threshold from traditional spiritual discipline to modern medical treatment and enriched with scholarly evidence, yoga gets scientific justification as a useful practice for maintaining health 26. It is one of the very few traditional disciplines that has gone through this exam and gained confirmation. It seems that yoga has come full circle by providing the techniques for living a meaningful and purposeful life, which are important both from a medical and spiritual point of view. Moreover, through aspirations of health benefits, yoga has focused the individual on the spiritual aspect of existence. Acknowledgement This work was supported by the Ministry of Education, Science and Technological Development, Serbia. References 1 Aurobindo S, The Synthesis of Yoga, 5 th edn, (Pondicherry, India: Sri Aurobindo Ashram Publication Department), Geden DA, The philosophy of Upanishads, (Cosimo), Iyengar BKS, Light on Yoga: The Definitive Guide to Yoga Practice, (Londo, UK: HarperCollins Publishers), King R, Orientalism and Religion: Postcolonial theory, Indian and The Mystic East, (New York, Routledge), Khalsa SB, Yoga as a therapeutic intervention, Principles Pract Stress Manage, 3 (2007) McCall T, Yoga as Medicine: The Yogic Prescriptions for Health and Healing, (Bantam Book, New York), Hart J, An overview of clinical applications of therapeutic yoga, Altern Comple Ther, 14(1) (2008) Anand BK, Yoga and medical sciences, Indian J Physiol Pharmacol, 35 (1999) Feuerstein G,The yoga tradition: its history, literature, philosophy, and practice, (Hohm Press, Prescott, Ariz), Sharma KD, Yoga and naturopathy: The true science of healing, Indian J Tradit Knowle, 1(1) (2002) Tiwari S, Highlights of Scientific Yoga Research Trend in Kaivalyadhama Yoga Institute, Lonavla, India, Int Yoga J Sense, 2(1)(2012) Newcombe S, The development of modern yoga: A survey of the field, Religion Compass, 3(6) (1999) De Michelis E, A preliminary survey of modern yoga studies, Asian Medicine: Tradition and Modernity, 3(1) (2008) Singlenton M & Byrne J, Yoga in the modern world: Contemporary perspectives, (London and New York, Routledge), Khalsa SBS, Yoga as a therapeutic intervention: A bibliometric analysis of published research studies, Indian J Physiol Pharmacol, 48(3)(2004) Cramer H, Lauche R & Dobos G, Characteristics of randomized controlled trials of yoga: a bibliometric analysis, BMC Comple Alter Med, 14(1) (2014) Ross A & Thomass S, The health benefits of yoga and exercise: A review of comparison studies, J Altern Comple Med, 16(1) (2010) Li AW & Golsmith CA, The effects of yoga on anxiety and stress, Altern Med Rev, 17(1) (2012) Malhotra V, Singh S, Singh KP, Sharma SB, Madhu SV, Gupta P & Tandon OP, Effects of yoga asanas and pranayama in non-insulin dependent diabetes mellitus, Indian J Tradit Knowle, 3(2) (2004) Kumar K, A study on the impact on stress and anxiety trough Yoga nidra, Indian J Tradit Knowle, 7(3) (2008) Bonura KB, The psychological benefits of yoga practice for older adults: evidence and guidelines, Int J Yoga Therapy, 21 (2011) Singlenton M, Yoga body: The origin of modern posture practice, (Oxford University Press), Krishnan S, Personality development through yoga practices, Indian J Tradit Knowle, 5(4) (2006) Nikić P, Concept of the Yoga Intelligence, Int Yoga J Sense, 1(1) (2011) BrayantE, The Yoga Sutras of Patanjali: A New edn, Translation and Commentary, (New York, USA: North Point Press), Woodyard C, Exploring the therapeutic effects of yoga and its ability to increase the quality of life, Int J Yoga, 42(2) (2011) 49.