Interoceptive Sensibility Mediates the Relationship Between Pain Severity and Emotional Distress

Pain and emotion are strongly related, yet the mechanisms mediating their relationship remain unclear. Interoception, the representation and regulation of internal bodily sensations, has been implicated in pain-related and emotional processes. Altered interoception has been demonstrated in chronic pain (CP) and mental health conditions. This preregistered study examined whether interoceptive sensibility, the self-reported multi-dimensional tendency to monitor bodily sensations, mediated the bi-directional relationship between pain severity and emotional distress. Adults with mixed-etiology CP (n=203) and pain free controls (PFC; n=170) recruited from the community, and treatment-seeking patients with chronic orofacial pain (COFP; n=89) recruited from a clinic completed self-report measures of pain intensity, pain interference, emotional distress (depression, anxiety, anger) and interoceptive sensibility, specifically the Multidimensional Assessment of Interoceptive Awareness (version 2) and Body Perception Questionnaire. Compared to PFC, both CP groups reported greater pain intensity, pain interference, and emotional distress, together with a differential interoceptive profile reflecting greater noticing and perceiving of their bodily sensations, while being more worried and having less trust in these sensations (p-values<0.001). These interoceptive dimensions did not correlate with pain intensity, yet correlated differentially between groups with emotional distress and pain interference: not-worrying in CP and COFP (remotional=-0.40 and -0.64; rpain=-0.26 and -0.41), noticing in COFP (remotional=0.43; rpain=0.39), and trusting in CP (remotional=-0.42; rpain=-0.30). Partial mediation of the pain interference-emotional distress relationship was demonstrated by these interoceptive dimensions in these groups. Findings support a mechanistic role for interoception in linking the functional burden of CP with emotional distress, offering clinically relevant targets for interventions.