452 An Intrinsic Pathway in the Brain Underlying the Relationship Between Pain Catastrophizing and Chronic Pain in Temporomandibular Disorders

Abstract

OBJECTIVES/GOALS: Pain Catastrophizing is a negative coping mechanism involving rumination, magnification, and helplessness and is associated with worse chronic pain. The neurobiological mechanisms underlying this relationship are poorly understood. We aim to examine the intrinsic activity of a functional pathway in patients with chronic orofacial pain. METHODS/STUDY POPULATION: This is the second phase of a parent study examining genetics, placebos, and the brain in temporomandibular disorders (TMD). We intend to recruit 120 of the original 398 TMD patients for this phase. Participants completed the Graded Chronic Pain Scale to assess TMD pain intensity and disability and the Pain Catastrophizing Scale. Behaviorally, pain catastrophizing scores and pain intensity and disability will be analyzed using structural equation modeling. Resting-state functional magnetic resonance imaging will be used to record intrinsic brain activity. The functional connectivity between the posterior cingulate, anterior insula, and periaqueductal grey will be assessed as a causal pathway relating pain catastrophizing to pain intensity and disability. Mediation analyses will be used to test causality. RESULTS/ANTICIPATED RESULTS: We anticipate that greater engagement in catastrophic thinking about pain increases the functional connectivity strength between the posterior cingulate, anterior insula, and periaqueductal grey, which ultimately leads to heightened perception of pain intensity and disability. Therefore, we expect to see increased functional connectivity in those with high pain catastrophizing levels as compared to those with low pain catastrophizing levels, and that this pathway will mediate the relationship between pain catastrophizing and pain intensity and disability. Further, we predict that helplessness will most strongly correlate with the change in functional connectivity as compared to rumination and magnification. Results will be presented in full at the conference. DISCUSSION/SIGNIFICANCE: Understanding how pain catastrophizing can influence chronic pain pathways will not only promote a more integrative approach to chronic pain management but will also help identify the mechanisms by which pain itself develops and persists in the particularly vulnerable pain population of TMD.