Complementary and alternative medicines (CAM) in the management of asthma: an examination of the evidence.

Although individuals are using Complementary and Alternative Medical (CAM) therapies to help manage their asthma, there is no clear direction in the current guidelines for the use of CAM in asthma. This literature review undertakes to determine the current science regarding the use of CAM in asthma management. Electronic literature searched all EBM Reviews, Medline, OVID full text, and PubMed and National Complementary and Alternative Medication databases for Randomised Controlled Trials (RCT) published in English between 1997 and 2002 with keywords "asthma" and "complementary medicine" or "complementary therapy" or "alternative medicine" or "alternative therapy." Abstracts (N=197) were reviewed for inclusion in the review and duplicates discarded (N=65). Abstracts of non-RCT studies, review articles, and surveys were also discarded (N=66). Abstracts discussing environmental control measures and pharmaceutical alternatives to steroid therapy were discarded (N=9). The 15 final studies were grouped within three categories: mind-body and relaxation, manual therapies, and diet and reviewed for statistical and clinical significance, suggesting some CAM therapies have shown minimally significant improvements in asthma quality of life (breathing exercises) or pulmonary function (relaxation) and immune function (relaxation and acupuncture) in select asthma populations. Although CAM therapy is being used in the management of asthma, these 15 studies show a tendency to little or no significant difference between placebo or sham therapy. This may be due, in part, to the enhanced placebo effect of sham therapies used as control and the small size of most studies. Although the changes in the immune function seen in two studies are provocative, these changes did not translate to changes in lung function. More research is needed to assist in determining the efficacy of CAM therapies in asthma management.