Alternative Medicine
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Alternative medicine is
an integral part of the healthcare of many
Australians. Approximately half of our population use at least one
non-medically prescribed alternative medicine each year, and about
20% of Australians visit an alternative medicine
practitioner.1 The estimated annual
expenditure is over $900 million.1 There are probably many
reasons for this widespread use of alternative medicine; one that has
been suggested is a growing dissatisfaction with orthodox
medicine.2 That alternative medicine
is of increasing relevance to orthodox medicine is illustrated by the
finding that almost two-thirds of United States medical schools have
courses on alternative or complementary medicine.3
Despite the demand for alternative medicine, there is a paucity of rigorous evidence about its effectiveness; there are few studies, and those that exist are often inconclusive. For instance, a meta-analysis of placebo-controlled trials of homoeopathy found "insufficient evidence that homoeopathy is clearly efficacious for any single condition", but, interestingly, that homoeopathy may be better than placebo for seasonal allergies and postoperative ileus.4 On balance, it must also be acknowledged that there are many gaps in the evidence about the effectiveness of orthodox medicine; however, orthodox medical practitioners are increasingly committed to evidence-based practice.5 A major challenge for evidence-based orthodox medicine is the availability of high quality clinical studies to form its evidence. For alternative medicine, there is a similar, if not greater, challenge that is demonstrated in this issue of the Journal. Liu and Douglas reviewed published reports (in English and Chinese) on the use of Chinese herbal medicines for acute respiratory infections (ARI);6 Bowler et al studied the efficacy of Buteyko breathing techniques (BBT) in the management of asthma.7 Both articles highlight the difficulties in designing and implementing clinical research for interventions outside of the double-blind randomised controlled trial (RCT) of conventional drug therapy. In the systematic review of Chinese herbal medicines for ARI by Liu and Douglas, we learn of 27 studies that evaluated these products using RCT or controlled clinical trial methods.6 Although it is clear that scientists are trying to establish the efficacy of alternative therapies using widely accepted methods, the quality of the studies was insufficiently rigorous to allow conclusions to be drawn about the efficacy of herbal medicines. Specific problems with the reports included inadequate information about randomisation, and doubts about the quality of outcome data and statistical analysis. Liu and Douglas did identify one preparation, Shuang Huang Lian, as a promising remedy worthy of further study. The reviewers identify approaches that may lead to more rigorous evaluation of this form of alternative medicine. The evaluation of BBT by Bowler et al was designed to overcome many of the limitations in clinical methodology that occurred in the trials of Chinese herbal medicines.6 Buteyko breathing techniques are based on the premise that the pathophysiology in asthma is due to hypocapnia as a result of hyperventilation.7 Participants are taught a series of exercises that purport to correct hyperventilation and hypocapnia. As well as comparing BBT with placebo breathing and relaxation exercises for managing asthma, Bowler et al addressed the question of mechanism of action by testing directly whether BBT corrected hyperventilation and hypocapnia. They found no benefit of BBT compared with placebo breathing and relaxation techniques on objective measures of asthma, such as forced expiratory volume in one second, peak expiratory flow, and exacerbations, despite the study having adequate power to detect an important difference. However, there were important changes in other outcomes, including a significant reduction in the self-reported use of short-acting bronchodilators and trends for reduction in the self-reported use of inhaled steroids and for improved quality of life. The dilemma of having inconsistent results is made more complex by the potential of bias associated with the unanticipated failure of matching for telephone contacts when some of the BBT subjects were contacted frequently to ensure compliance with BBT. This co-intervention could bias the results, especially for self-reported outcomes, by creating an expectation of greater benefit from BBT. An additional observation of the study was that BBT did not correct hypocapnia, although it was associated with a reduction in minute ventilation. Consequently, it remains unclear whether hypocapnia and hyperventilation are important contributors to the pathophysiology of asthma, or merely a consequence of asthma itself. Overall, the study showed no improvement in the clinical severity of asthma in the BBT group, but there was a significant reduction in the use of beta2-agonists. These data indicate that some patients can cope with less medication and suffer no loss of control of their asthma. If this is the case generally, then many patients are taking unnecessary medication, leading to increases in adverse effects and expenses for these drugs. Medical practitioners should review regularly the asthma therapy of their patients and consider dosage reductions (back-titration).8 Both the above studies reinforce the need to improve the quality and quantity of evidence that is used to guide healthcare practice. This applies equally to both alternative and orthodox therapies. The increasing recognition of this need has prompted greater emphasis on clinical epidemiology in undergraduate and postgraduate education. The Cochrane Collaboration is an example of an organised approach to the production and dissemination of high quality evidence. It has an Airways Group, which produces systematic reviews of therapy in respiratory disease and includes alternative therapies in its scope.9 As demonstrated by the studies of Liu and Douglas and Bowler et al, particular problems in trials of alternative therapy include adequate blinding and the use of an appropriate placebo. Nonetheless, these are crucial elements to obtaining valid results. They require ingenious solutions, as demonstrated recently by the report of a "placebo" acupuncture needle.10 Essential in the evaluation of any healthcare intervention is the detection of adverse effects. Compared to the substantial regulation and surveillance of orthodox medicine, the relative lack of regulation for alternative medicine may suggest that it is without adverse effects. That this is not the case was most recently illustrated by reports in the New England Journal of Medicine on the direct, indirect and potential harm from alternative medicines, summarised in an accompanying editorial.11 The risks included delay in the use of scientifically validated therapy, and contamination of traditional or herbal medicines with oestrogenically active chemicals, digitalis, heavy metals and a neurologically active solvent. The need for attention to the safety of alternative medicines has been recognised in Australia.12 In summary, alternative therapies should be approached in the same way as some parts of orthodox medicine are evaluated now and how most, if not all, will be assessed in the future. That is, if shown to be effective and safe, they should be part of the range of interventions available to patients. Ineffective or unsafe therapies should be abandoned, and unproven interventions should be evaluated in high quality clinical trials. As proposed in the New England Journal of Medicine editorial,11 it may be time to stop using the terms "orthodox" and "alternative" and to classify health interventions into whether or not they have been shown to do more good than harm in scientifically valid studies -- an evidence-based approach to healthcare.
Michael J Hensley
Professor of Medicine, University of Newcastle, Newcastle, NSW and Director of Respiratory Medicine, John Hunter Hospital, Newcastle, NSW
Peter G Gibson
©MJA 1998 | |||
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