ARTICLE IN PRESS Respiratory Medicine (2004) 98, 687–696 EVIDENCE-BASED REVIEW An overview of two Cochrane systematic reviews of complementary treatments for chronic asthma: acupuncture and homeopathy$ R.W. McCarneya,*, T.J. Lassersonb, K. Lindec, B. Brinkhausd aDepartment of Psychological Medicine, Imperial College, Room 4.06, Paterson Centre, 20 South Wharf Road, London W2 1PD, UK bCochrane Airways Group, Public Health Sciences, St George’s Hospital Medical School, London, UK cDepartment of Internal Medicine II, Centre for Complementary Medicine Research, Technical University Munich, Munich, Germany dInstitut fur Sozialmedizin and Epidemiologie, Charite´, Berlin, Germany KEYWORDS Summary Background: Acupuncture and homeopathy are commonly used comple- Systematic reviews; mentary treatments for chronic asthma. This review summarizes two recently Asthma; updated Cochrane systematic reviews that assess the safety and efficacy of Acupuncture; homeopathy or acupuncture in individuals with chronic stable asthma. Inclusion criteria: Only randomized-controlled trials were considered for inclu- Homeopathy sion. Statistical aggregation of the data was undertaken where possible. Search strategy: Searches for both reviews were done with the assistance of the Cochrane Airways Group, and through electronic alerts. Results: Acupuncture: 11 studies with 324 participants met the inclusion criteria. Trial reporting was poor, and the trial quality was deemed inadequate to generalize the findings. There was variation in the type of active and sham acupunctures, the outcomes assessed and the time points measured. The points used in the sham arm of some studies are used for the treatment of asthma according to traditional Chinese medicine. Two studies used individualized treatment strategies, and one study used a combination strategy of formula acupuncture with the addition of individualized points. No statistically significant or clinically relevant effects were found for acupuncture compared with sham acupuncture. When data from two small studies were pooled, no difference in lung function was observed (post-treatment FEV1): standardized mean difference 0.12, 95% confidence interval À0.31 to 0.55). Conclusion: Acupuncture: There is not enough evidence to recommend the use of acupuncture in the treatment of asthma. Further research needs to be undertaken, and this should take into account the different types of acupuncture practiced. Results: Homeopathy: Six trials with a total of 556 people were included in the $The following Cochrane reviews have been cited in this evidence-based review: McCarney RW, Brinkhaus B, Lasserson TJ, Linde K. Acupuncture for chronic asthma. The Cochrane Library, Issue 3, 2004; and McCarney RW, Linde K, Lassersson TJ. Homeopathy for chronic asthma. The Cochrane Library, Issue 3, 2004. Copyright Cochrane Library, reproduced with permission. *Corresponding author. Tel.: þ 44-20-7886-7697; fax: þ 44-20-7886-1995. E-mail address: [email protected] (R.W. McCarney). 0954-6111/$ - see front matter & 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.rmed.2004.05.005 ARTICLE IN PRESS 688 R.W. McCarney et al. review. These trials were all placebo-controlled and double-blind, but were of variable quality. Standardized treatments in these trials are unlikely to represent common homeopathic practice where treatment tends to be individualized. The results of the studies are conflicting in terms of effects on lung function. There has been only a limited attempt to measure a ‘‘package of care’’ effect (i.e. the effect of the medication as well as the consultation, which is considered a vital part of individualized homeopathic practice). Conclusion: Homeopathy: There is not enough evidence to reliably assess the possible role of homeopathy in the treatment of asthma. Further studies could assess whether individuals respond to a ‘‘package of care’’ rather than the homeopathic intervention alone. & 2004 Elsevier Ltd. All rights reserved. Background bodily function.7 Other methods of stimulation have been used, such as the use of pressure Bronchial asthma is a major health problem and is (acupressure) and, more recently, the use of lasers. associated with significant morbidity. The reported One important but under-researched aspect of prevalence of asthma in children ranges from treatment is the subjective element of this com- 1.6%–35% in different countries, whereas the plex therapy. It is difficult to remove acupuncture prevalence of asthma symptoms in adults ranges treatment from its context, and this has not been from 4.1%–32% in Europe.1 Although the symptoms addressed in existing research. can be controlled by drug treatment in most patients, effective low-risk, non-drug strategies would provide a valuable adjunctive or alternative treatment in asthma management. Homeopathy There is much interest in complementary and alternative medicine (CAM), and its use is growing Homeopathy is one of the most widespread and at a significant rate.2 The term CAM covers a large controversial forms of complementary or alterna- number of therapies, sometimes with no apparent tive medicine. Surveys among general practitioners connection, as they can often have diverse origins, and chest physicians suggest that a significant theories, and appearances. There are no hard and proportion might seek additional advice from 8,9 fast definitions of what exactly constitutes CAM, homeopaths. but a good practical definition is ‘‘interventions Homeopathy is based on the principle of ‘‘like neither taught widely in medical schools nor curing like’’ (similia similibus curentur): a prepara- generally available in hospitals’’.3 Although the tion that would cause certain symptoms is used to use of CAM can be the result of dissatisfaction with cure those symptoms. Homeopathic remedies are conventional treatment,4 it can also be an expres- prepared as ‘‘potencies’’, with several consecutive sion of taking personal responsibility in dealing with dilutions with vigorous shaking (succussion) be- chronic illness.5 Two common types of CAM used by tween each dilution step. The molecules contained people with asthma are homeopathy and acupunc- in a homeopathic remedy are diluted beyond ture. In one survey, 9% of responders had used Avogadro’s number. This has led some investigators homeopathy and 5% had used acupuncture in the to question whether homeopathic therapy could 10 previous year.6 have any effect over placebo. However, propo- nents of homeopathy claim that the remedies act through biophysical pathways, and all include the idea of some form of information transfer from the Acupuncture diluted substance to the diluting agent.11–14 At least four basic types of homeopathy are Acupuncture is a form of therapy derived from differentiated in this review. For chronic diseases traditional Chinese medicine, which involves the such as asthma, the ‘‘classical’’ homeopathic stimulation of points on the body with the use of approach is probably most widespread. In classical needles for therapeutic or preventative purposes. homeopathy, the choice of the remedy is deter- As the use of acupuncture has become more mined by the individual symptoms of each patient. prevalent in the West, these theories have been As a consequence, different asthma patients might developed to fit in with a Western understanding of receive very different remedies, fitting their ARTICLE IN PRESS Two cochrane systematic reviews of complementary treatments for chronic asthma 689 individual symptom patterns. Classical homeopathy effects model and relative risk was calculated. For involves detailed and intense history taking, which continuous data (e.g. lung function), we used a might give rise to significant non-specific ‘‘package fixed-effects model and weighted mean difference of care’’ effects. ‘‘Clinical’’ homeopathy, by con- was calculated. Continuous data measured on trast, uses the same remedy in patients presenting different metrics (e.g. % predicted and L/min) with a relatively homogeneous pathology or con- were pooled using a standardized mean difference stellation of symptoms. (SMD). Two reviewers assessed concealment of In some conditions (e.g. atopic asthma), a randomization, blinding of patients and evaluators, diluted causative agent (e.g. potentized pollen) and likelihood of selection bias after randomization may be used. This is called ‘‘isopathy’’. The use of (whether intention-to-treat analysis was carried fixed combinations of several homeopathic reme- out). We stratified the data on the basis of age dies (so-called ‘‘complex’’ remedies or ‘‘complex (adults vs children). Data from parallel and cross- homeopathy’’) for one or a limited number of over studies were separated. conditions is popular among general practitioners or ‘‘beginners’’ of homeopathy, and is particularly widespread in Europe, especially Germany and The acupuncture review France. The objective of this overview is to summarize Method two recently published Cochrane reviews.15,16 In these reviews, we evaluated the evidence for the For the acupuncture review, we searched the efficacy of acupuncture and (separately) homeop- Asthma and Wheez* register of the Cochrane athy for the treatment of patients with stable Airways Group and the Alternative Medicine Elec- chronic asthma. These reviews15,16 can be referred tronic Database from the British Library, in August to for more detailed information. We have detailed 2003, for all trials including the following words: the methodology common to both reviews, and acupuncture OR acupressure