Potential use of salivary TNF-α as a vaccine-induced pain biomarker in people with cerebral palsy and communication disorders

Abstract

[eng] BackgroundPain in people with cerebral palsy (CP) has been classically underestimated and poorlytreated, particularly in individuals with impaired communication skills.ObjectiveTo analyze changes in different salivary metabolites and pain behavior scales after a painfulprocedure in adults with CP and adults with typical development.MethodsSalivary levels of sTNF-α, sIgA, Cortisol, FRAP, ADA and Alpha Amylase, as well as 3observational pain scales (Wong-Baker, Non-Communicating Adults Pain Checklist andFacial Action Coding System) were assessed before and after an intramuscular injection in30 Individuals with CP and 30 healthy controls. Video recording of face expression was performedduring the procedure for offline analysis.ResultsPain in subjects with CP was higher than in healthy controls after the intramuscular injectionas displayed by observational scales. sTNF-α experienced a significant post-stimulusincrease in both groups and that increase shows a tendency to correlate with the observationalscales scores. Other biomarkers classically associated with stress (cortisol, AlphaAmylase) remain stable.ConclusionsTNF-α might be a promising pain indicator. Further research using controlled painful stimuliof greater intensity and pain self-reports, would be necessary to better understand its use asa pain biomarker.