- Endocrine Biomarkers of Pain in Non-Communicative Patients: A Study Protocol

Non-verbal patients (e.g., stroke patients, persons with profound autism, or intellectual disability) may be unable to communicate their pain. Pain is known to affect hormones such as catecholamines, and cytokines. This neurophysiological response may be utilised as a pain biomarker in non-verbal patients. Thirty-eight non-verbal patients, with autism and intellectual disability living in care homes, participates with electrocardiogram, blood tests for catecholamines and monocyte chemoattractant protein-1 (MCP-1), interleukin-1 receptor antagonist (IL-1RA), interleukin-8 (IL- 8), transforming growth factor-beta 1 (TGFβ1), and interleukin-17 (IL-17), and continuous heart rate (HR) measures. We identify situations that result in increased HR, which may be an indicator of pain, and modify the care procedures to alleviate any potential pain. We measure pain-related biomarkers in blood before the change in care. Then again 2 and 4 weeks after the changes in procedures have been implemented. We hypothesise that a change in care procedures to reduce the occurrence of painful situations (as identified by increased HR) will lead to lower levels of pain- related cytokines and catecholamines in blood. Such findings will contribute to the field of neuroendocrinology by exploring the potential use of biomarkers of pain in non-communicative patient care. This study has the potential to advance the understanding of neuroendocrine correlates to pain in non-verbal individuals. This knowledge may help to reduce the number of painful episodes in non-communicative patients' everyday lives and improve their quality of care.