Placebo response strong with asthma
Reuters Health
Thursday, June 28, 2007
NEW YORK (Reuters Health) - Findings from a new study indicate that asthma patients often exhibit a placebo response -- that is, they show an improvement in their condition even when they just think they are being treated.
Interestingly, the patients not only report an improvement in their disease, but objective tests indicate a benefit as well, according to the report in the Journal of Allergy and Clinical Immunology.
Previous reviews have suggested that placebo benefits are restricted to subjective responses, like pain, the authors explain, but are ineffective for objective physiological outcomes.
Dr. Margaret E. Kemeny from the University of California, San Francisco, and colleagues investigated whether there was a placebo response in objective measures of lung function in 55 patients with asthma.
The results of the methacholine challenge test, which gauges how well a particular drug opens constricted airways, showed that placebo did, in fact, seem to improve lung function. However, the benefit was even greater when the patients were given salmeterol, a real drug used to treat asthma.
Placebo responders were significantly younger than nonresponders, the results indicate, but otherwise the groups did not differ on demographic and psychological characteristics.
Kemeny and colleagues conclude: "The placebo response in patients with asthma is important in understanding the limitations of clinical research studies and in maximizing safe and effective therapies. This article confirms the existence of a strong placebo response in an objective and clinically relevant measure of disease activity."
SOURCE: Journal of Allergy and Clinical Immunology, June 2007.
Reuters Health