Can pill placebo augment cognitive-behavior therapy for panic disorder?

Toshi A Furukawa¹ , Norio Watanabe¹ , Ichiro M Omori¹ and Rachel Churchill²

¹Department of Psychiatry and Cognitive-Behavioral Medicine, Nagoya City University Graduate School of Medical Sciences, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan

²Section of Evidence-Based Mental Health, Health Services Research Department, Institute of Psychiatry, King's College London, University of London, UK

author email corresponding author email

BMC Psychiatry 2007, 7:73doi:10.1186/1471-244X-7-73


Published:	20 December 2007

Abstract

Background

In a number of drug and psychotherapy comparative trials, psychotherapy-placebo combination has been assumed to represent psychotherapy. Whether psychotherapy plus pill placebo is the same as psychotherapy alone is an empirical question which however has to date never been examined systematically.

Methods

We conducted a systematic review and meta-analysis of randomised controlled trials (RCTs) that directly compared cognitive-behavior therapy (CBT) alone against CBT plus pill placebo in the treatment of panic disorder.

Results

Extensive literature search was able to identify three relevant RCTs. At the end of the acute phase treatment, patients who received CBT plus placebo had 26% (95%CI: 2 to 55%) increased chances of responding than those who received CBT alone. At follow-up the difference was no longer statistically significant (22%, 95%CI: -10% to 64%).

Conclusion

The act of taking a pill placebo may enhance the placebo effect already contained in the effective psychotherapeutic intervention during the acute phase treatment. Theoretically this is an argument against the recently claimed null hypothesis of placebo effect in general and clinically it may point to some further room for enhancing the psychotherapeutic approach for panic disorder.