Parameters of asthma and manipulation study questioned.

To the Editor: I read the article by Susan E. Bockenhauer, DO, et al, “Quantifiable effects of osteopathic manipulative techniques on patients with chronic asthma” (J Am Osteopath Assoc. 2002;102:371-375), with interest and concern. Although I commend the authors for attempting to investigate a potential link between manipulation and asthma, I must say that the article and the study itself are severely flawed. Let me start with the study’s selection process. Only ten patients participated in the study—including smokers and nonsmokers—an extremely small population sample. Further, all of the participants were female. There was wide variability in the severity of asthma among the patients, yet no mention of pulmonary function testing and the criteria used to determine how these patients were selected. Measurements of the thoracic wall were done with a tape measure, which is difficult to duplicate and fraught with potential error. No significant difference in peak flow rates was apparent; in fact, peak flow rates after the manipulative procedure were worse. In addition, the concept that thoracic excursion has anything to do with the severity of (or relief from) asthma is a concept that is not based in science. The authors admit that the slight improvement in symptoms after manipulative procedures was not statistically significant. Finally, the standard measure of pulmonary function in asthma is obtained via spirometry. Unfortunately, spirometry was not used during this study. To produce a credible study that investigates a potential link between asthma and manipulation, the manipulative techniques used need to be standardized, the definition of the asthmatic patient must be stated, a sample size that provides sufficient representation must be used, and better methods of providing placebo therapy need to be devised. In addition, spirometric testing needs to be included with a measure of response to bronchodilator therapy. Until such studies can show any benefit, we should not delude ourselves into thinking that manipulative therapy has a beneficial role in asthma.