Salivary biomarkers in pain assessment: an integrative review

Objective: To identify the main salivary biomarkers described and the techniques used for saliva sample collection in studies related to pain assessment in patients undergoing painful procedures or experiencing painful diseases Methods: An integrative literature review was conducted via bibliographic searches in the Virtual Health Library (VHL), MEDLINE/PubMed, CINAHL, and EMBASE databases for the period from 2009 to 2019; data were collected in October and November 2019. The DeCs health descriptors and the Medical Subject Headings (MeSH) were used to answer the guiding question: "Which salivary biomarkers are used in pain assessment and how are they employed?" A descriptive analysis of the articles was performed; data were collected and recorded in a spreadsheet developed for the present study. Results: Of the 126 published articles identified, 22 articles were included for analysis. The articles were mainly regarding adults undergoing painful procedures or patients experiencing painful diseases. The main salivary biomarkers evaluated were alpha-amylase and cortisol, and the main saliva collection techniques were Salivette (R) and passive collection. Conclusion: The studies indicated that objective pain measurement is a challenge. The main salivary biomarkers evaluated were cortisol and alpha-amylase, and the main technique employed for saliva sample collection was Salivette (R). The dosage of salivary molecules is emerging for use as a complement in pain assessment in patients of different ages undergoing painful procedures or experiencing painful diseases.