Background & Aims

Childhood adversity (CA) is robustly associated with persistent pain in adulthood. However, the physiological relationship between CA and persistent pain is unclear. CA and persistent pain are both associated with neural and immune reactivity in adulthood; therefore, we aimed to clarify whether immune reactivity is associated with provoked differences in nociceptive function in adults with a history of CA.

Methods

96 healthy adults with a history of CA ranging from mild to severe CA, underwent psychophysical testing before and after in vivo neural provocation (high-frequency electrical stimulation) and then, separately, in vivo immune provocation (influenza vaccine administration). The neural and immune provocations were performed on the same day, separated by ±90 minutes. Proxies for vulnerability to persistent pain were surface area of secondary skin hypersensitivity after neural provocation, and change in conditioned pain modulation (test stimulus: pressure pain threshold; conditioning stimulus: cold water immersion) after immune provocation. Immune reactivity was assessed by IL-6 and TNF-? expression after in vitro lipopolysaccharide provocation of whole blood.

Results

96 full datasets have been collected, and cytokine assays will be run in early 2024, in time for complete results to be presented at the World Congress. We hypothesise that levels of IL-6 and TNF-? after in vitro immune provocation will be positively associated with the area of secondary skin hypersensitivity after in vivo neural provocation, and negatively associated with a change in conditioned pain modulation after in vivo immune provocation.

Conclusions

Characterising immune reactivity to both neural and immune provocations within the same individual stands to improve insight into the complex neuro-immune contributions to risk of persistent pain in people with a history of CA.

References

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Presenting Author

Gillian J Bedwell

Poster Authors

Gillian J Bedwell, MSc

University of Cape Town

Lead Author

E-mail

Mark Hutchinson

University of Adelaide

Lead Author

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Romy Parker

University of Cape Town

Lead Author

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Peter Kamerman

University of the Witwatersrand

Lead Author

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Victoria Madden

University of Cape Town

Lead Author

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Topics

  • Mechanisms: Psychosocial and Biopsychosocial