Abstract
Background: Nocebo effects can adversely affect the experience of physical symptoms, such as pain and itch. Nocebo effects on itch and pain have shown to be induced by conditioning with thermal heat stimuli and reduced by counterconditioning. However, open-label counterconditioning, in which participants are informed about the placebo content of the treatment, has not been investigated, while this can be highly relevant for clinical practice. Furthermore, (open-label) conditioning and counterconditioning has not been investigated for pain modalities relevant to musculoskeletal disorders, such as pressure pain. Methods: In a randomized controlled trial, we investigated in 110 healthy female participants whether nocebo effects on pressure pain combined with open-label verbal suggestions can be (1) induced via conditioning and (2) reduced via counterconditioning. Participants were allocated to either a nocebo- or sham-conditioning group. Next, the nocebo group was allocated to either counterconditioning, extinction or continued nocebo conditioning; sham conditioning was followed by placebo conditioning. Results: Nocebo effects were significantly larger after nocebo conditioning than sham conditioning (d = 1.27). Subsequently, a larger reduction of the nocebo effect was found after counterconditioning than after extinction (d = 1.02) and continued nocebo conditioning (d = 1.66), with effects similar to placebo conditioning (following sham conditioning). Conclusions: These results show that (counter)conditioning combined with open-label suggestions can modulate nocebo effects on pressure pain, which provides promise in designing learning-based treatments to reduce nocebo effects in patients with chronic pain disorders, particularly for musculoskeletal disorders. Significance: Few studies have investigated the efficacy counterconditioning to reduce nocebo effects. Whereas typically deceptive procedures are used, these are not ethically appropriate for use in clinical practice. The current study demonstrates that open-label counterconditioning in a pain modality relevant for many chronic pain conditions may be a promising new strategy for reducing nocebo effects in a non-deceptive and ethical manner, which provides promise in designing learning-based treatments to reduce nocebo effects in patients with chronic pain disorders.
| Original language | English |
|---|---|
| Pages (from-to) | 831-847 |
| Number of pages | 17 |
| Journal | European Journal of Pain (United Kingdom) |
| Volume | 27 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - Aug 2023 |
| Externally published | Yes |
Bibliographical note
Funding Information:The authors thank Matthew Howard from King's College London for lending their handpiece to use with our pressure pain device for the purposes of this study. Also, the authors thank Elio Sjak-Shie and the technical support team of Leiden University (SOLO) for their support with the pressure pain device during this study. Furthermore, the authors like to thank Wouter Weeda (Leiden University) for his statistical advice. The authors also thank all student assistants involved in data collection.
Funding Information:
This study was funded by a VICI grant from the Netherlands Organization for Scientific Research (NWO; grant number 45316004), awarded to A.W.M. Evers. The pressure pain device used in this study was borrowed from Karolinska Institute, Sweden, and the handpiece for applying pressure pain was borrowed from King's College London, UK.
Publisher Copyright:
© 2023 The Authors. European Journal of Pain published by John Wiley & Sons Ltd on behalf of European Pain Federation - EFIC ®.