The effect of hypnosis on pain and peripheral blood flow in sickle-cell disease: a pilot study

Abstract

Background

Vaso-occlusive pain crises (VOCs) are the “hallmark” of sickle-cell disease (SCD) and can lead to sympathetic nervous system dysfunction. Increased sympathetic nervous system activation during VOCs and/or pain can result in vasoconstriction, which may increase the risk for subsequent VOCs and pain. Hypnosis is a neuromodulatory intervention that may attenuate vascular and pain responsiveness. Due to the lack of laboratory-controlled pain studies in patients with SCD and healthy controls, the specific effects of hypnosis on acute pain-associated vascular responses are unknown. The current study assessed the effects of hypnosis on peripheral blood flow, pain threshold, tolerance, and intensity in adults with and without SCD.

Subjects and methods

Fourteen patients with SCD and 14 healthy controls were included. Participants underwent three laboratory pain tasks before and during a 30-minute hypnosis session. Peripheral blood flow, pain threshold, tolerance, and intensity before and during hypnosis were examined.

Results

A single 30-minute hypnosis session decreased pain intensity by a moderate amount in patients with SCD. Pain threshold and tolerance increased following hypnosis in the control group, but not in patients with SCD. Patients with SCD exhibited lower baseline peripheral blood flow and a greater increase in blood flow following hypnosis than controls.

Conclusion

Given that peripheral vasoconstriction plays a role in the development of VOC, current findings provide support for further laboratory and clinical investigations of the effects of cognitive–behavioral neuromodulatory interventions on pain responses and peripheral vascular flow in patients with SCD. Current results suggest that hypnosis may increase peripheral vasodilation during both the anticipation and experience of pain in patients with SCD. These findings indicate a need for further examination of the effects of hypnosis on pain and vascular responses utilizing a randomized controlled trial design. Further evidence may help determine unique effects of hypnosis and potential benefits of integrating cognitive–behavioral neuromodulatory interventions into SCD treatment.

Keywords:

• sickle-cell disease
• pain
• hypnosis
• blood

Acknowledgments

This research was supported by the National Heart, Lung, and Blood Institute (1U54HL117718 to TDC and LKZ).

Author contributions

RRB was the primary author of manuscript and conducted statistical analyses and interpretation of data. SRM was the secondary author of the manuscript, interpreted data, and provided expertise regarding sickle-cell disease. SE was the lead developer of the hypnosis protocol and conducted the hypnosis procedure with participants. KL assisted with development of laboratory assessment and conducted laboratory assessments with participants. TDC provided expertise regarding clinical aspects of sickle-cell disease. LKZ assisted with development of the overall study protocol and provided clinical expertise regarding the use of hypnosis for pain. JCT provided expertise on laboratory pain assessment and was the lead developer of the laboratory pain protocol. All authors contributed toward data analysis, drafting and revising the paper and agree to be accountable for all aspects of the work.

Disclosure

The abstract of this paper was presented at the 2016 American Society of Hematology meeting as a poster with interim findings. The authors report no conflicts of interest in this work.