Background & Aims

The placebo response is an integral part of the response to any analgesic treatment [1]. It is well documented that the communication and interaction between therapists and patients about the treatment could elicited expectations for benefit and improve treatment outcomes [2,3]. However, this knowledge has not yet translated into clinical practice, probably because virtually all evidence arises from experimental studies, or from clinical studies which their results are not informative to the adoption of this approach into routine clinical care. The aim of the current study was to assess the effects of positive information regarding the analgesic efficacy of the treatment on pain intensity after first request of analgesia following c-section.

Methods

Women undergoing c-section at Carmel Medical Centre were recruited and assigned into the “Regular Communication” or “Enhanced Communication” study arms. During the first 24 hours after the c-section, at first request of analgesic, participants reported their pain level on a Visual Analogue Scale (VAS) twice, at baseline and one hour following the administration of Metamizole. Participants assigned to the “enhanced communication” received positive information regarding the efficacy of the treatment, while in the “regular communication” study arm, no such information was provided. A repeated measures ANOVA with 2 time points and 2 study arms (regular or enhanced communication) was conducted to assess main effects and interactions on pain intensity.

Results

Out of 99 eligible women, a total of 80 women completed the study, with 38 women allocated to the regular communication study arm and 42 to the enhanced communication arm. A repeated measures ANOVA revealed a significant main effect of time, F(1,78) = 261.907, p<0.001, η²=0.771 but not group F (1,78) = 0.82, p=0.775. In addition, a significant interaction between time and group was found F(1,78) =22.142 p<0.001, η²=0.221.

Conclusions

The information provided by nurses regarding the efficacy of the analgesic given following c-section impacts treatment outcomes. The current study results provide direct ecological evidence for the additive value of positive information about analgesic treatment efficacy after c-section. We hope that this and other similar studies will assist in translating the powerful placebo effects into routine clinical care.

References

[1] Enck, P., Bingel, U., Schedlowski, M., & Rief, W. (2013). The placebo response in medicine: minimize, maximize or personalize? Nature Reviews. Drug Discovery, 12(3), 191–204. doi:10.1038/NRD3923

[2] Benedetti, F., Carlino, E., & Piedimonte, A. (2016). Increasing uncertainty in CNS clinical trials: the role of placebo, nocebo, and Hawthorne effects. In The Lancet Neurology (Vol. 15, Issue 7, pp. 736–747). Lancet Publishing Group. doi:10.1016/S1474-4422(16)00066-1

[3] Pollo, A., Amanzio, M., Arslanian, A., Casadio, C., Maggi, G., & Benedetti, F. (2001). Response expectancies in placebo analgesia and their clinical relevance. Pain, 93(1), 77–84. doi:10.1016/S0304-3959(01)00296-2

Presenting Author

Vered Cohen

Poster Authors

Vered Cohen

RN BA

The Cheryl Spencer Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel

Lead Author

Mariana Agostinho

Master

The Cheryl Spencer Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel

Lead Author

Roi Treister

The Cheryl Spencer Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel

Lead Author

Topics

  • Assessment and Diagnosis