W-27: Placebo Response Reduction Training in Chronic Low Back Pain: Comparison to Other Published Studies on Chronic Low Back Pain
Poster Presenter
Nathalie Erpelding
Associate Director, Research & Development
Analgesic Solutions United States
Objectives
To compare the placebo response in a randomized controlled trial that implemented a placebo response reduction training program to other published chronic low back pain (CLBP) studies.
Method
A systematic review was performed to identify double-blind randomized placebo-controlled parallel trials of systemic pharmacological treatments in subjects with CLBP of at least 3 months duration and a minimum of 4 weeks of treatment duration.
Results
A total of 610 studies were identified through the systematic review. Thirty-two articles met all criteria and were included in the review. We examined the percent of patients with a clinically relevant reduction in pain (=30%). Our results show that the trial implementing the placebo response reduction training had the smallest percentage of patients in the placebo group with a clinically relevant reduction in pain (i.e., 19.1%) compared to similar studies (mean =36.6%). That study also had half the variability in change in pain scores (standard deviation = 0.88) of the placebo group compared to the average variability in change in pain scores in the other trials (standard deviation = 1.65).
Conclusion
Placebo responses decrease the assay sensitivity of clinical trials, thus increasing sample size requirements and risk of trial failure. Several studies suggest that psychoeducational interventions to neutralize expectations of patients and research staff can reduce the placebo response in clinical trials. Based on our results, the study implementing placebo response reduction training showed a reduced clinically relevant placebo response. Our results also suggest that the placebo response reduction training may reduce variability in placebo response, thus decreasing the need for larger sample sizes. Due to the observational nature of this comparison, and the numerous differences between the clinical trials included in this systematic review, it is impossible to conclude that the lower placebo response seen in our study was due to the training alone. Nonetheless, the successful reduction of the placebo response seen in the trial suggests further investigation is warranted into the use of psychoeducational interventions to neutralize patient and staff expectations and lower placebo responses in clinical trials.
