Complementary and Alternative Medicine Part 1

Definitions

The term alternative medicine encompasses a spectrum of approaches to medical conditions not routinely used by conventional practitioners. Historically, the term has been associated with negative conceptions about medical practices that did not conform to accepted standards of care. The term complementary medicine has since evolved to describe a more positive, symbiotic relationship between unconventional medicine and conventional medicine. The field of complementary and alternative medicine (CAM) now encompasses a multitude of different approaches and beliefs that are generally linked by their emphasis on so-called natural modalities of healing and wellness. More and more, the term integrative medicine is being used, suggesting that CAM should be integrated into conventional care. This topic describes modalities that are complementary to conventional medicine in the United States; in other countries, many of these modalities are part of mainstream medical practice.

Classification

Patient demand, media attention, and the growth of an approximately $40 billion industry1 have stimulated leaders in governmental agencies and academic medicine to recognize and categorize CAM and to direct research initiatives on the subject. Although there is currently no universally accepted classification of CAM modalities, the National Center for Complementary and Alternative Medicine (NCCAM) has grouped CAM practices into five domains [see Table 1]. It should be recognized that these categories are not mutually exclusive. Certain practices will overlap (e.g., qigong is considered an energy therapy but is part of Chinese medicine, which is an alternative medical system). Also, as evidence emerges regarding mechanisms of action, safety, and efficacy, certain modalities will naturally move beyond the CAM label and become part of mainstream medicine.

Use of CAM

Prevalence and demographics

The widespread use of CAM by the public has been well documented. In 2002, about 62% of adults in the United States reported using at least one form of alternative medicine within the previous year.1 It has been estimated that 75% of people in the United States have used at least one CAM therapy over their life-time.1 Public-opinion surveys have suggested similar overall patterns of use in European countries, although the popularity of specific CAM modalities varies greatly from country to country.2 Patients across all demographic groups use alternative medicine. However, some surveys have noted that predictors of CAM use may include female gender, white race (as opposed to African-American or Hispanic), higher socioeconomic status, and higher levels of education.3,4 Many CAM users have chronic, non-life-threatening medical conditions,3,5 and they may have an interest in spirituality.6 A number of diagnosis-based surveys suggested exceptionally high usage of alternative medicine in patients with cancer,7 HIV infection,8 fibromyalgia,9 and inflammatory bowel disease.10

Public perception

The alternative-medicine movement has clearly been a public-driven process that has spanned decades. It was initially thought that this movement was primarily the result of dissatisfaction with conventional medicine.11 Subsequent studies have shown that this is not the case6,12 and that patients continue to see their conventional health care practitioners while using CAM therapies; however, about 27% of CAM users believe that conventional medicine will not help their health care problem.1 Two disturbing observations are that most patients do not disclose their use of alternative therapies to their physicians and that such patients are never asked about CAM use by their physicians.13 Furthermore, many patients feel no need to communicate their CAM use to their physicians because they believe that their physicians would be unable to understand and incorporate that information into their treatment plan.12,14 On the other hand, current data suggest that about one quarter of patients who use CAM do so on the advice of a conventional medical professional.1

A number of other factors have stimulated public use of alternative medical therapies. The fact that many CAM modalities emphasize natural forms of healing seems to form the fundamental basis for its use. Many patients desire a more holistic approach to their medical care.6 They may feel that conventional medicine focuses excessively on suppression of symptoms (e.g., pharmacologic lowering of elevated blood pressure) rather than addressing the root cause of symptoms. They believe that so-called natural products are better and safer than synthetic medications. In many cases, they may turn to alternative medical practices to get relief from chronic conditions that have not responded to conventional symptomatic therapy. Additionally, media hype, direct-to-consumer advertising, and the wide-spread availability of information over the Internet have all played a role in the popularity of CAM and have served to expand the public’s health care choices. Of concern to many physicians is that these choices are frequently based on insufficient basic science or clinical evidence.

Table 1 NIH/NCCAM Classification of Complementary and Alternative Medicine Practices

Category	Examples
Alternative medical systems	Ayurveda (traditional Indian medicine), traditional Chinese medicine, homeopathy
Mind-body interventions	Biofeedback, hypnosis, meditation, prayer
Biologic-based therapies	Dietary therapy, herbal medicine, megavitamins, shark cartilage
Manipulative and body-based methods	Chiropractic, massage therapy, craniosacral therapy
Energy therapies	Therapeutic touch, qigong, bioelectric field manipulation, reiki

NIH/NCCAM—National Institutes of Health/National Center for Complementary and Alternative Medicine

Research Concerns

Scientific issues

One of the defining characteristics of alternative medicine is the paucity of definitive evidence supporting mechanism of action, efficacy, and safety. Although a number of clinical trials on CAM have been published, the overall quality of those trials is quite poor, primarily because of inadequate sample size, randomization, and blinding.15,16 Additionally, publication bias may be common in the international literature. Critical reviews of published studies on CAM therapies from a number of countries have shown that the studies almost universally report positive findings pertaining to CAM. This suggests that studies reporting negative findings may never make it to press.17,18

There are a number of barriers to the proper evaluation of CAM studies. First, the establishment of adequate control groups is frequently very difficult. Studies on acupuncture, for example, have attempted to incorporate a placebo control by stimulating nonacupuncture points, stimulating actual points unrelated to the treated condition, or applying pressure instead of inserting needles. Some critics argue that so-called sham acupuncture is an inadequate placebo that does not preserve subject blinding. Proponents of acupuncture may argue that such control methods are still potentially therapeutic because of their possible positive effect on the flow of subtle energy through the body. Similar pitfalls are inherent in mind-body research. In the study of personal prayer, of prayer groups, or of intercessory prayer that occurs in the presence of the patient, the intervention group can be compared with those who do not partake in organized prayer. Such a design clearly does not lend itself to adequate blinding. Additionally, any positive results could reflect aspects of prayer that are unrelated to its spiritual qualities (e.g., relaxation), making definitive conclusions difficult.

Another major problem with interpreting CAM research stems from inconsistencies in the intervention groups. Drawing meaningful conclusions from herbal-medication studies is difficult because extracts are not standardized. For example, although positive effects have been seen in a number of published clinical trials with the plant genus Echinacea for treatment of upper respiratory tract infections, definitive conclusions cannot be drawn because of variation in the species of plant studied, the part of the plant utilized (root, leaf, or flower), and extraction methods.19 In addition, the manufacturing processes within and between companies vary widely, so that the concentration of active product in an over-the-counter preparation is rarely known.

Lack of standardization is also a flaw in acupuncture research. Many different types of acupuncture are practiced around the world, and each type may utilize a completely different set of points for the same condition. Even among providers who practice the same type of acupuncture, variation in point selection is common because approaches differ on the basis of the patient’s history and physical examination and on the acupuncturist’s personal style. This individualization of therapy is alluring to patients, but the unwillingness of practitioners to agree on what constitutes acceptable technique challenges conventional study methodology. CAM practitioners often criticize the typical scientific model that employs randomized clinical trials because in clinical practice, there are multiple interventions, such as mind-body and herbal treatments, that occur simultaneously. Thus, any research in the area may have to be multidimensional.

Financial issues

Unlike conventional pharmaceutical and medical-device research, large-scale studies in CAM derive their funding almost exclusively from government sources. Modalities such as prayer, acupuncture, and massage therapy are not lucrative enough endeavors to support large, privately funded trials. Dietary supplements, such as herbs, may have a significant profit potential, but the incentive for research is weakened by the fact that herbs, like other natural substances, cannot be patented. In addition, the rules and regulations under which foods and natural products are regulated differ from those for pharmaceuticals, which must meet stringent standards of efficacy and safety.

In an effort to boost CAM research, the United States Government set up NCCAM (http://nccam.nih.gov), under the National Institutes of Health (NIH). With an annual working budget of about $120 million, NCCAM has funded a number of individual projects, as well as specialty centers around the country [see Table 2].

Specific CAM Modalities

Alternative medical systems

Traditional Chinese Medicine

Acupuncture Acupuncture has been used for centuries as a component of traditional Chinese medicine (TCM). It involves the insertion of thin needles into specific points on the skin to facilitate the movement of energy (qi). Chinese medicine posits that qi (pronounced chee) flows along distinct channels (called meridians) in the body and that balanced circulation of qi is a prerequisite for good health. A block in the flow of qi can result in either a deficiency or an excess of qi along a meridian; those imbalances can be corrected by accurate needle placement (or pressure, in the case of acupressure) at specific points on the body. Acupuncture practitioners often enhance the effect of the needles by electrical stimulation; manual manipulation (e.g., twirling); or moxibus-tion, which involves burning mugwort (Artemisia vulgaris) on the acupuncture point or the end of the needle. Practitioners of TCM frequently combine acupuncture with other modalities, including herbal remedies, to achieve the desired physiologic response. Each treatment is individualized on the basis of the patient’s history and physical examination, including pulse and tongue examinations. Many types of acupuncture are practiced today; a few examples are traditional Chinese acupuncture, five-elements acupuncture, and auricular acupuncture.

To date, no clear physical mechanism of action has emerged to explain the potential therapeutic response to acupuncture. Changes in blood flow and biologic mediators (e.g., hormones, neurotransmitters, and endorphins) have been shown to occur with needle manipulation.20-23 There are numerous published clinical studies on acupuncture treatment for a variety of ailments. Most are small in size and have methodologic flaws that make consensus difficult. Nevertheless, in 1997, an NIH consensus panel concluded that there is clear evidence to support the use of acupuncture for postoperative, chemotherapy-induced, and probably pregnancy-associated nausea and vomiting.23 Although the data are less compelling, evidence also suggests a positive effect of acupuncture on idiopathic headache,24 fibromyalgia,25,26 and os-teoarthritis of the knee.27 Current evidence does not support its use for smoking cessation,28 asthma,29 or low back pain.30

If done correctly, acupuncture is quite safe.31 Rare case reports of serious adverse events, including skin infections, hepatitis, pneumothorax, and cardiac tamponade, seem to stem from inadequate sterilization of needles and practitioner negligence.

Table 2 Government-Funded Specialty Centers for Research into Complementary and Alternative Medicine

Specialty	Center and Location
Acupuncture—addiction	Minneapolis Medical Research Foundation, Minneapolis; New England School of Acupuncture, Watertown, Massachusetts
Acupuncture— neuroimaging	Massachusetts General Hospital, Charlestown
Aging and women’s health	Columbia University, New York
Antioxidants	Oregon State University, Corvallis
Arthritis	University of Maryland, Baltimore
Botanical treatment of age-related diseases	Purdue University, West Lafayette, Indiana
Botanical dietary supplements for women’s health	University of Illinois, Chicago
Botanical dietary supplements	UCLA, Los Angeles
Cancer	Johns Hopkins University, Baltimore
Cancer and hyperbaric oxygen	University of Pennsylvania, Philadelphia
Cardiovascular diseases	University of Michigan, Ann Arbor
Cardiovascular disease and aging in African Americans	Maharishi University of Management, Fairfield, Iowa
Chiropractic	Palmer Center for Chiropractic Research, Davenport, Iowa
Craniofacial disorders	Kaiser Foundation Hospitals, Portland, Oregon
Frontier medicine (biofield science)	University of Arizona, Tucson
Frontier medicine (therapeutic touch)	University of Connecticut, Farmington
Neurodegenerative diseases	Emory University School of Medicine, Atlanta
Neurologic disorders	Oregon Health Sciences University, Portland
Pediatrics	University of Arizona Health Sciences Center, Tucson
Phytomedicine	University of Arizona, Tucson
Phytonutrient and phytochemical studies	University of Missouri, Columbia

To prevent transmission of infection, most practitioners now use disposable needles. Minor side effects, including insertion-site pain or bleeding, fatigue, and vasovagal syncope, are probably more common.34

Homeopathy

Homeopathy is one of the most controversial modalities in CAM, primarily because of its theoretical implausibility. The roots of homeopathy trace back to the 1700s, when it was first described by Samuel Hahnemann. Homeopathic principles revolve around two basic tenets: the law of similars and the principle of serial dilutions. According to the law of similars, substances that cause symptoms in healthy people can cure those same symptoms in people who are sick. A number of examples of this principle exist in conventional medicine. Digoxin is used to treat the same arrhythmias that it is capable of inducing. Similarly, methylphenidate, which is a stimulant, has been used to treat attention-deficit/hyperactivity disorder.35

The principle of serial dilutions (or the minute dose) is another controversial aspect of homeopathy. According to this principle, medications can have a biologic effect even if diluted to levels at which the original substance is undetectable (a so-called homeopathic dose).

A homeopath’s approach to patients differs from that of the conventional physician. Homeopaths concentrate almost exclusively on subjective symptoms and sensations. They choose medications on the basis of the patient’s symptomatology, rather than on the objective medical diagnosis. This results in the use of a wide array of different medications for any one conventionally diagnosed condition.These provings are matched to a patient’s symptoms to determine the therapeutic regimen. Patients are typically followed closely so that the homeopath can titrate dosing schedules.

Meta-analyses of a number of trials of homeopathic remedies have suggested an effect superior to placebo.36,37 However, many studies and reviews on specific medications have shown negative or inconclusive results.37-39 Given the conflicting clinical data and the lack of evidence regarding mechanism of action, it is difficult to support the general use of homeopathy until more high-quality research is available.

Because homeopathic remedies typically contain little or no detectable active ingredients, serious side effects are rare. Homeopathic preparations are generally marketed as over-the-counter remedies and are usually exempt from government requirements for finished product testing or expiration dating. In the United States, the Food and Drug Administration requires that all homeopathic remedies list the indications for their use, the ingredients, instructions for safe use, and dilutions. Dilutions in a ratio of 1:10 are labeled with an X, and dilutions in a ratio of 1:100 are labeled with a C. For example, a 3X product has been diluted 1:10 three times; a 3C product has been diluted 1:100 three times. It should also be noted that these remedies are not restricted to the 10% alcohol limit of conventional drugs.40

Mind-body interventions

The relationship between psychological stress and physical health has been studied extensively over the past 30 years. Despite positive results from some trials, interventions designed to alter the stress response have not become part of mainstream medical practice. The reluctance of physicians to incorporate mind-body strategies into their therapeutic armamentarium likely stems from their unfamiliarity with such interventions; time constraints; and the lack of a clear mechanistic pathway to disease. Furthermore, many physicians may feel that these therapies need to be patient driven rather than physician driven, because they require significant changes in self-care.

Figure 1 Possible mechanism of mind-body interventions. (CRF— corticotropin-releasing factor)

The proposed theory of mind-body medicine stems from work done in the early 1900s. The fight-or-flight response was described as physiologic preparation for combating or fleeing an external threat.41 Stimulation of the hypothalamus and increased sympathetic nervous system activity lead to neurohormonal stimulation and increases in blood pressure, heart rate, respiratory rate, and muscle tension. This response has historically been protective, ensuring survival in the face of physical danger. In today’s society, however, we are continually faced with innumerable stressors that can elicit the fight-or-flight response, yet fighting or running away is inappropriate or impossible. The body is primed for action but can take none. This chronic physiologic stimulation is thought to increase the likelihood of disease. Furthermore, the development of a chronic disease may stimulate the response through a feedback mechanism, potentially worsening the condition. The effect of the chronic fight-or-flight response on immunosuppression and cytokine and hormone production needs greater elucidation.

Mind-body interventions can elicit a relaxation response that may prevent or aid in the treatment of a number of medical ail-ments42 [see Figure 1]. A number of modalities can be used for this purpose. Many people have incorporated yoga, meditation, or self-hypnosis into their daily self-care regimen. Several clinical studies have suggested that there are positive results from mind-body modalities for many conditions [see Table 3]. As with other CAM interventions, however, limitations in study methodology and sample size, as well as lack of an adequate control, make definitive conclusions difficult.

The mind-body category also encompasses techniques for which a mechanism is not even remotely understood. No physical explanation for distant healing modalities—such as intercessory prayer, spiritual healing, and mental healing—is currently accepted, despite some evidence for positive treatment effects.43 No harmful effects are seen when most mind-body interventions are used as an adjunct to conventional care. However, there is concern that patients might choose exclusive use of one or more of these methods in lieu of appropriate diagnosis and therapy.

Biologic-based therapies

Biologic therapy is the most popular of all fields of CAM. Its popularity stems from its similarity to the process of using conventional medications. Some people consider biologics to be a possible quick fix for their ailments, without the need for physician visits or potentially harmful prescription medications. Others turn to biologics in the hope of preventing potentially serious diseases through the use of so-called natural substances.

Dietary supplements, including herbal and nonherbal products, make up the preponderance of medications in this category. The supplement industry has become a billion-dollar business, largely as a result of the loosening of federal regulations. The Dietary Supplement Health and Education Act (DSHEA) of 1994 expanded the definition of dietary supplements to include vitamins, amino acids, herbs, and other botanicals. Furthermore, under DSHEA, supplements no longer require premarket testing for safety and efficacy. Supplements are assumed to be safe unless proved otherwise by the FDA. Given the number and variety of products currently available, the FDA’s ability to effectively regulate all products after they have been marketed is limited. An example of the regulatory process was the banning of products containing ephedra. The FDA first expressed concern over the herb in 1997, when it proposed limitations on its use. The General Accounting Office viewed these limitations as inappropriate, because of insufficient evidence proving harm. It took 7 years (and a few high-profile deaths) for the FDA to be able to effect a ban on ephedra.44 Although most dietary supplements are well tolerated and are associated with few adverse effects, the potential for harm from the lack of regulation can be seen from examples of misidentification of plant species,45 contamination with heavy metals, and addition of pharmaceutical agents.46,47

Overall, there is only limited evidence supporting the use of most dietary supplements. Most clinical trials have been small, nonrandomized, or unblinded. In general, physicians and patients should view herbs as medications. Physicians should advise patients to be wary of products for which grandiose claims are made, because misleading advertising is common.48 The potential for significant toxicity and drug interactions does exist.

The list of currently used supplements is immense, and this topic can touch on only the most popular [see Tables 4 through 6]. More comprehensive resources for dietary supplements (and other CAM modalities) are now available [see Table 7].