CAM Use in Asia-Pacific

May 1, 2011

Applied Clinical Trials Supplements

Supplements-05-01-2011, Volume 0, Issue 0

Use of complementary and alternative medicine among adult cancer patients.

Proper history taking is one of the first things that is taught to doctors in medical school. This includes medications that the patient is taking concurrently. With the growing interest in the use of complementary and alternative medicine globally, doctors should be more aware of its effects and interactions with the body and with other medicines as well.



The US National Center for Complementary and Alternative Medicine (NCCAM) defines complementary and alternative medicine (CAM) as a "group of diverse medical and healthcare systems, practices, and products that are not generally considered part of conventional medicine."1 Complementary medicine is utilized in concert with conventional medicine, whereas alternative medicine is used as a replacement for conventional medicine.

Traditional medicine, as defined by the World Health Organization (WHO), "is the sum total of knowledge, skills, and practices based on the theories, beliefs, and experiences indigenous to different cultures, that are used to maintain health, as well as to prevent, diagnose, improve, or treat physical and mental illnesses."2 When other populations use the traditional medicine of other cultures, this is now termed as complementary and alternative medicine.

It is widely known that some of the more popular traditional medicines originated from Asia, such as Indian Ayurveda and Traditional Chinese Medicine (see Traditional Asian Medicine sidebar). Thus, it is commonly presumed that CAM is more widely practiced in this region than in the West. WHO estimates that in some Asian and African countries, 80% of the population actually depends on traditional medicine as their primary healthcare. The exact prevalence rates of CAM use for most of the countries in Asia are unknown as there are very few well conducted population-based studies.

Traditional Asian Medicine

In more developed countries, WHO estimates that 70% to 80% of the population have used some form of CAM. A national population-based survey conducted in Australia in 2005, revealed that 69% of those surveyed used at least one form of CAM, while 44% visited a CAM practitioner.3 A survey in 2007 in the United States, found that 38% of adults, and 12% of children are using some form of CAM.4 Among cancer patients, CAM use is increasing in popularity, from 34% in 19905 to 55% in 2002.6

This article examines CAM use among cancer patients in selected countries in Asia, and doctor's attitudes and knowledge about it. However, it is difficult to assess and compare CAM usage and prevalence across studies as there are differences in what constitutes CAM, the study population and methodology of the studies used, and the types of CAM reimbursed by insurance companies. It must be remembered also that what constitutes CAM is often culturally dependent. Ayurveda medicine in India for example, is often regarded as orthodox medicine. Traditional Chinese Medicine has been around for thousands of years, with a theoretical and practical approach to management of disease, albeit different from that of the Western framework.

CAM use in the general population

In general, CAM use, especially Traditional Chinese Medicine (TCM), is more accepted by Asian governments. In China, TCM has its own medical schools, hospitals, and research institutes, as well as its own department in the Ministry of Public Health.7 Since 1996, TCM use in Taiwan has been reimbursable by the National Health Insurance (NHI). Thus people are free to choose between conventional Western style medicine and Traditional Chinese Medicine,8 although NHI only reimburses TCM in certain forms. In Singapore, the TCM Practitioner Act was passed in November 2000. It requires TCM practitioners to be registered with the TCM Practitioners Board. The Board, aside from registering TCM practitioners, also regulates the professional conduct and ethics of TCM practitioners, while accrediting TCM courses and schools.9 Korea has Oriental medical schools that teach Oriental medicine (as opposed to Western medicine). Students go through a six-year medical program and need to pass a national licensing exam before practicing.10

In Asia, CAM use in the general population ranges from 50% to 76%.8,11-14 Females consistently are more likely to use it. The significance of age, marital status, educational level, financial capacity, and tumor site differed among countries; could be due to the sample population surveyed and study methodology used.

In Japan, the most common therapies used were massage; vitamins; health food, including dietary supplements; acupressure; and kampo (see Traditional Japanese Medicine sidebar).11,13 This is similar to the Koreans, where the five most common types of CAM therapies used were dietary supplements, Korean Oriental Medicine, non-processed and non-prescribed herbs, animal extracts, and diet-based therapies. In multiracial, multiethnic Singapore, the Chinese were the most frequent users with TCM the most widely used.12 Among the vast array of available traditional Chinese medicine, the majority of patients in Taiwan (86%) use Chinese herbal remedies.7 Only 11% use acupuncture, and 3% use traumatology manipulative therapies. TCM use among the Chinese is not surprising, as it has been around for more than 2,000 years and is deeply ingrained in their culture. One of the exceptions is Hong Kong, where only 4% prefer to use TCM for their medical problems.15 During British colonial rule, Western medicine dominated the healthcare system, while TCM use was left outside the mainstream. It wasn't until the hand over of the city's sovereignty in 1997 that it was formally recognized. In 1999, the Chinese Medical Council of Hong Kong was established to act as a regulator and ensure the professional standard of TCM practitioners.

Traditional Japanese Medicine

Despite high TCM use, more patients still visited Western medicine clinics than TCM clinics for their illnesses.8 Patients more frequently use CAM for maintenance of health rather than for treatment of illness, which is usually musculoskeletal in nature.

It is noteworthy that patients usually do not inform their physician about their CAM use.11-13 Patients might find it hard to tell their doctor for fear of a negative reaction and disapproval of its use.

CAM use in cancer patients

Prevalence and profile of patients using CAM. CAM use among cancer patients ranges from 45% to 98%. Among leukemic patients in India, prevalence of CAM use is about 57%.16 A study done at the Ambulatory Treatment Unit of the National Cancer Center Singapore revealed that 56% of patients were currently using CAM, while 44% had used CAM prior to their cancer diagnosis.17 Factors found to be positively associated with CAM use were race (Chinese), education level (secondary level and below), and prior CAM use. Tumor type, gender, and economic status were factors not found to be associated with CAM use.

A nationwide survey in Japan in 2002 showed the prevalence of CAM use among cancer patients to be 45%, and approximately 26% in non-cancer patients. They were usually female, less than 61 years old, had a higher education, had previously received chemotherapy, were dissatisfied with conventional treatments, and were attending palliative care units (as opposed to cancer centers and related hospitals). This profile is similar to that in Western countries. Patients with lung, breast, or hepatobiliary cancers also used CAM more frequently.18

Prevalence of CAM use among cancer patients in South Korea range from 50% to 78%.19,20 Patient profile revealed them to be younger and more educated.19 Patients who also initiated complementary therapy tend to be female, of younger age (≤60 years old), with a higher household income, with private insurance, and with a diagnosis of stomach or liver cancer.20

A study done in Taiwan in 1995 showed the prevalence of CAM use in a cancer clinical trial referral unit to be 64%.21 As TCM use in the general population has generally increased by 29% annually, this figure may be higher in present times.8 This is borne out by Yang et coll. who, in May 2008, reported that 98% of cancer patients receiving outpatient chemotherapy also used CAM.8,22 This figure is very similar to a study among breast cancer patients in Shanghai, China, wherein 97% of patients reported CAM use after diagnosis.23 Females and patients less than 70 years old tended to use CAM more frequently than males. Religious affiliation and educational level were also shown not to be significant factors.21

Among leukemic patients in a tertiary care hospital in north India, more than half admitted to using CAM. Males used them more often than females, and across all age groups, although adults aged 36 and above more frequently. Patients from rural communities also used CAM more often, compared to urbanites, who more often used conventional therapy alone. Rural patients also tended to be illiterate, or educated till primary level, compared to urban patients who have tertiary level education.16

Types of CAM used. Asian cancer patients more often use food supplements, herbs, or medicinal plants/mushrooms instead of physical therapies such as yoga and acupuncture.

Based on NCCAM categories, the Singaporean study excluded energy therapies, mind-body interventions, and manipulation and body-based methods. The most commonly used CAM were food supplements (59%), TCM (48.5%), special diet such as organic fruit and vegetables (40.5%), and vitamins (39.6%). Among food supplements, bird's nest and essence of chicken were consumed most often. Herbs prescribed by licensed Chinese physicians were used by 53.6% of patients taking TCM. The rest consumed lingzhi (15.4%), and Chinese proprietary medicines (7.5%) in finished dosage forms such as pills and capsules.17

A vast majority of those surveyed in Japan relied on CAM products (96%) rather than on non-medical therapies. Of these, more than 60% took certain types of mushrooms, thought to be an interferon inducer or immunomodulator. Only 7% of patients used Chinese herbs. Non-medical therapies such as qigong, moxibustion, and acupressure were used by slightly less than 4% of patients.18

In Korea, medicinal mushrooms were also used most frequently, being used by 67% of patients. This was followed by herbs (54%), vegetable diets (51%), and ginseng (46%). However, if we go into specifics, extracts of Korean red ginseng was used most often; followed by Phellinus linteus, a medicinal mushroom; vegetable green juice; and Ulmus davidiana, a medicinal tree. Physical therapy such as moxibustion, heat therapy, and massage were used about 10% of the time.19

In an earlier study in Taiwan, Ling chi (lingzhi)—with or without herbs—are used about 60% of the time, followed by any combination of pills plus powdered prescription, pharmaceutical concoctions (bottled in vials), and Ling chi (lingzhi)—with or without herbs—in 25% of patients.21 Patients were only able to describe the physical form of treatment received which accounts for the vagueness of the medicine used. What was noteworthy was that only 10% of patients got their prescription from a qualified Chinese medical practitioner, with 30% of all prescriptions obtained from licensed sellers of Chinese herbs. In a later study, biologically-based therapies were used more than 75% of the time, among which grapeseed and ginseng featured prominently.22 However, there was also a significant proportion who did not know the name of the herbs they were taking.

In the Shanghai, China study among breast cancer patients, supplements were the most common type of CAM consumed followed by Chinese herbal medicine (CHM) and physical walking. Supplement and CHM users tend to have higher income, with menopausal symptoms, and a history of prior Tamoxifen use. Patients with chemotherapy or radiotherapy and cancer metastasis engaged in more physical activity.23

In India, it is not surprising that Ayurveda is used most commonly.16

Reason for CAM use and perceived effectiveness. Asian patients in general tend to use CAM more for augmentation or maintenance of health than for treatment of the cancer itself.

Singaporean cancer patients' main reason for taking CAM was to boost immunity (53.7%), and for general health (16.7%). On the other hand, the two most common reasons for not taking CAM was fear of interference with chemotherapy (24.4%) and that oncologists were against CAM use (22.2%). Other reasons cited were: lack of advice regarding CAM use from oncologist (7.4%), patients only wanted to take medications prescribed by their oncologists during anticancer treatment (5.7%), and financial difficulties affording CAM (4%). Still, 74% of the patients surveyed felt that CAM was effective for the purpose they were using it, while 23% felt unsure about is effectiveness.17

Among Japanese patients, 24% of CAM users felt that it had positive effects, such as tumor shrinkage, tumor growth inhibition, pain relief, lesser side effects from chemotherapy, and generally feeling better. Sixty-nine percent of the patients however were unclear about the beneficial effects of CAM; more than 60% had no adverse effects, while only about 5% felt some form of adverse effect. It should be noted however that among CAM users, the prevalence of patients treated with concomitant conventional therapy is 62%.18

The following, in order, are the main reasons why Korean patients use CAM: nutritional support, strengthen the body, boost immunity, increase appetite, and anti-cancer effect. More than half of patients felt no benefit from using CAM. Of those who had positive effects, 13% had positive emotional or psychological comfort, 8% had an increase in physical strength, and 6% just generally felt that CAM was effective. Similar to Japan, about 5% of patients felt adverse effects from using CAM. Thus, majority of patients are still willing to continue with it. 19

TCM use is popular in China, and is deeply ingrained in their culture. Patients use TCM for a variety of reasons, one of which is to avoid or decrease the adverse effects of conventional therapy. There is a perception that chemotherapy damages the vital essence—"the root of a person, so that you lose the basic energy to fight the disease." There is a conception also that Western therapy consists of standard products and dosages for all patients, which contrasts with TCM, where the assessment and prescription is tailored to the individual, thus maximizing beneficial effects, reducing adverse events, and neutralizing potential toxicity. TCM is perceived to be safe, cheap, controls symptoms well and has long-term effects in recovery.24

Patients hope for a miracle cure with CAM treatment among Indian leukemic patients. Adverse drug reactions with conventional treatment were also a factor. However, the majority were dissatisfied with CAM, as it was considered expensive, time consuming, and difficult to follow.16

Patient-doctor interaction. Despite the high use of CAM among cancer patients, patients are generally still unwilling to inform their doctors about CAM use. Doctors on their part are also unaware of its use among their patients.

The majority of Western-trained oncologists in the region have been asked about CAM therapies by their patients, and the practice is neither to encourage nor discourage its use. It is still the belief that CAM is ineffective against cancer, with the lack of reliable evidence being the main reason. Most also feel that there is drug interaction between anticancer drugs and CAM products.25,26

More than 50% of Singaporean and Korean cancer patients who use CAM informed their oncologist of CAM use.17, 26 This is in contrast to Japan and India where the majority of patients do not even consult their doctor about CAM use.16,18 A common reason for not informing their physician was because the physicians themselves never asked them about it. Since CAM is perceived to be effective, patients were also afraid that their doctor might discourage its use.

Future directions

Education. Medical students themselves feel ill equipped to deal with CAM for their future practice.27,28 There is a fear that patient's trust will be compromised if they are unable to discuss this properly. Most express some knowledge about CAM or TCM, and perceive it to be more efficacious than Western medicine in the management of pain, viral infections, cancer, or chemotherapy-related symptoms such as nausea and vomiting. However, it is generally believed to be lacking in scientific evidence leading to hesitancy in its use. With the extensive selection of CAM available, the majority express limited knowledge for most of these options. Thus, there is interest in learning more so that they are able to talk about this with their patients in the future.

Impact on clinical trials. A lot of research on CAM focus on symptomatology or as a supportive therapy. Acupuncture is well known to help selected patients with cancer pain. However, oncologists' concerns for lack of scientific evidence is not unfounded as there is a lack of large-scale, randomized clinical trials comparing CAM with conventional chemotherapy in treating cancer.29 It is also a well-known fact that there are herb-drug interactions, one of the most famous being St. John's wort reducing the effectiveness of warfarin. St. John's wort taken with imatinib may reduce imatinib's clinical efficacy. Salicylate herbs such as white willow and wintergreen can also potentially increase methotrexate blood levels and toxicity. However, with the extensive list of herbs and chemotherapy drugs available, more studies need to be done on this matter. In the meantime, it is a good idea to keep in mind when designing clinical trials on conventional therapy to ask patients about the use of CAM, as this may have an inadvertent impact on the drug's adverse event profile, be it positive or negative.

Charmaine Bautista,*MD, is Medical Director Oncology Asia-Pacific at i3, 89 Science Park Drive, #03-03 The Rutherford Science Park One, Singapore, e-mail: Thomas Moehler, MD, PhD, Head Therapeutic Area Oncology (International) and Richard Joubert, PhD, Medical Research Scientist both at i3, Taunusstrasse 9, D-65189 Wiesbaden, Germany.

*To whom all correspondence should be addressed.


1. National Center for Complementary and Alternative Medicine (NCAM),

2. World Health Organization, "Factsheet on Traditional Medicine,"

3. C. C. Xue, A. L. Zhang, V. Lin, C. Da Costa, and D. F. Story, "Complementary and Alternative Medicine Use in Australia: A National Population-Based Survey," Journal of Alternative and Complementary Medicine, 13 (6), 643-650 (2007).

4. P. M. Barnes, B. Bloom, and R. Nahin, "Complementary and Alternative Medicine Use among Adults and Children: United States, 2007," CDC National Health Statistics Report #12, (December 10, 2008).

5. D. M. Eisenberg, R. B. Davis, S. L. Ettner, S. Appel, S. Wilkey, M. Von Rompay, and R. C. Kessler, "Trends in Alternative Medicine Use in the United States, 1990-1997: Results of a Follow Up National Survey," Journal of the American Medical Association, 280 (18), 1569-75 (1998).

6. S. H. Saydah and M. S. Eberhardt, "Use of Complementary and Alternative Medicine Among Adults with Chronic Diseases: United States 2002," Journal of Alternative and Complementary Medicine, 12 (8) 805-812 (2006).

7. T. Hesketh and W. X. Zhu, "Traditional Chinese Medicine: One Country Two Systems," British Medical Journal, 315 (7100), 115-117 (1997).

8 F. P. Chen, T. J. Chen, Y. Y. Kung, Y. C. Chen, L. F. Chou, F. J. Chen, and S. J. Hwang, "Use Frequency of Traditional Chinese Medicine in Taiwan," BMC Health Services Research, 7 (26) (2007).

9. Ministry of Health of Singapore,

10. S. I. Lee, Y. H. Khang, M. S. Lee, and W. Kang, "Knowledge of, Attitudes Toward, and Experience of Complementary and Alternative Medicine in Western Medicine—and Oriental Medicine-Trained Physicians in Korea," American Journal of Public Health, 92 (12) 1,994-2,000 (2002).

11. H. Yamashita, H. Tsukayama, and C. Sugishita, "Popularity of Complementary and Alternative Medicine in Japan: A Telephone Survey," Complementary Therapies in Medicine, 10 (2) 84-93 (2002).

12. M. K. Lim, P. Sadarangani, H. L. Chan, and J. Y. Heng, "Complementary and Alternative Medicine Use in Multiracial Singapore," Complementary Therapies in Medicine, 13 (1) 16-24 (2005).

13. S. Hori, I. Mihaylov, and J. C. Vasconcelos, "Patterns of Complementary and Alternative Medicine Use Amongst Outpatients in Tokyo, Japan," BMC Complementary and Alternative Medicine, 8 (14) (2008).

14. S. M. Ock, J. Y. Choi, Y. S. Cha, J. Lee, M. S. Chun, C. H. Huh, S. Y. Lee, and S. J. Lee, "The Use of Complementary and Alternative Medicine in a General Population in South Korea: Results from a National Survey in 2006," Journal of Korean Medical Science, 24 (1) 1-6 (2009).

15. V. Chung, E. Wong, J. Woo, S. V. Lo, and S. Griffiths, "Use of Traditional Chinese Medicine in the Hong Kong Special Administrative Region of China," Journal of Alternative and Complementary Medicine, 13 (3) 361-368 (2007).

16. M. Gupta, N. Shafiq, S. Kumari, and P. Pandhi, "Patterns and Perceptions of CAM Among Leukaemia Patients Visiting Hematology Clinic of a North Indian Tertiary Care Hospital," Pharmacoepidemiol Drug Safety, 11 (8) 671-676 (2002).

17. V. Shih, J. Y. L. Chiang, and A. Chan, "Complementary and Alternative Medicine (CAM) Usage in Singaporean Adult Cancer Patients," Annals of Oncology, 20 (4), 752-757, (2009).

18. I. Hyodo, N. Amano, K. Eguchi, M. Narabayashi, J. Imanishi, M. Hirai, T. Nakano, and S. Takashima, "Nationwide Survey on Complementary and Alternative Medicine in Cancer Patients in Japan," Journal of Clinical Oncology, 23 (12) 2,645-2,654 (2005).

19. M. J. Kim, S. D. Lee, D. R. Kim, Y. H. Kong, W. S. Sohn, S. S. Ki, J. Kim Y. C. Kim, C. J. Han, J. O. Lee, H. S. Nam, Y. H. Park, C. H. Kim, K. H. Yi, Y. Y. Lee, and S.H. Jeong, "Use of Complementary and Alternative Medicine Among Korean Cancer Patients," The Korean Journal of Internal Medicine, 19 (4) 250-256 (2004).

20. S. G. Kim, E. C. Park, J.H. Park, M. I. Hahm, J. H. Lim, and K. S. Choi, "Initiation and Discontinuation of Complementary Therapy Among Cancer Patients," Journal of Clinical Oncology, 25 (33) 5,267-5,274 (2007).

21. J. M. Liu, H. C. Chu, Y. H. Chin, Y. M. Chen, R. K. Hsiek, T. J. Chiou, and J. Whang-Peng, "Cross Sectional Study of Use of Alternative Medicines in Chinese Cancer Patients," Japanese Journal of Clinical Oncology, 27 (1) 37-41 (1997).

22. C. Yang, L. Y. Chien, and C. J. Tai, "Use of CAM Among Patients with Cancer Receiving Outpatient Chemotherapy in Taiwan," Journal of Alternative and Complementary Medicine, 14 (4) 413-416 (2008).

23. Z. Chen, K. Gu, Y. Zhneg, W. Zheng, W. Lu, and X. O. Shu, "The Use of Complementary and Alternative Medicine Among Chinese Women with Breast Cancer," Journal of Alternative and Complementary Medicine, 14 (8) 1049-55 (2008).

24. W. Xu, A. D. Towers, P. Li, and J. P. Collet, "Traditional Chinese Medicine in Cancer Care: Perspectives and Experiences of Patients and Professionals in China," European Journal of Cancer Care, 15 (4) 397-403 (2006).

25. I. Hyodo, K. Eguchi, T. Nishina, H. Endo, M. Tanimizu, I. Mikami, S. Takashima, and J. Imanishi, "Perceptions and Attitudes of Clinical Oncologists on Complementary and Alternative Medicine—a Nationwide Survey in Japan," Cancer 97 (11) 2,861-2,868 (2003).

26. D. Y. Kim Do, B. S. Kim, K. H. Lee, M. A. Lee, Y. S. Hong, S. W. Shin, andS. N. Lee, "Discrepant Views of Korean Medical Oncologists and Cancer Patients on Complementary and Alternative Medicine," Breast Cancer Research and Treatment, 40 (2) 87-92 (2008).

27. A. S. Yeo, J. C. H. Yeo, C. Yeo, C. H. Lee, L. F. Lim, and T. L. Lee, "Perceptions of Complementary and Alternative Medicine Amongst Medical Students in Singapore—a Survey," Acupuncture in Medicine, 23 (1) 19-26 (2005).

28. W. C. W. Wong, A. Lee, S. Y. S. Wong, S.C. Wu, and N. Robinson, "Strengths, Weaknesses, and Development of Traditional Chinese Medicine in the Health System of Hong Kong: Through the Eyes of Future Western Doctors," Journal of Alternative and Complementary Medicine, 12 (2) 185-189 (2006).

29. A. Munshi, L. H. Ni, and M.S. Tiwana, "Complementary and Alternative Medicine in Present Day Oncology Care: Promises and Pitfalls," Japanese Journal of Clinical Oncology, 38 (8) 512-520 (2008).

Related Content:

Trial Design