Sensing Your Body: Interoceptive Awareness and Medically Unexplained Symptoms

According to contemporary theories of medically unexplained symptoms (MUS), alterations in interoception play a major role in symptom development and maintenance. Nevertheless, the mechanisms underlying this relationship remains unclear. To address this unresolved issue, we investigated whether individuals with varying degrees of MUS differ in different facets of interoceptive awareness as assessed with the Multidimensional Assessment of Interoceptive Awareness (MAIA) questionnaire. In study 1, 486 individuals were screened with an online version of the Screening for Somatoform Disorders (SOMS-2). Individuals with a SOMS index below 5 (low reporter, n=32) and above 20 (high reporter, n=32) were invited to fill in the MAIA. High symptom reporter had lower scores on the Not-Distracting, Not-Worrying, and Trusting subscales, and higher scores on the Emotional Awareness subscale (Cohen´s d=.70–1.16). In study 2, individuals with DSM-IV somatoform disorder (SFD; n=25) were compared to individuals with major depressive disorder (MDD; n=24) and healthy controls (HC; n=25). The SFD and MDD groups had lower scores on the Not-Distracting, Attention Regulation, Self-Regulation, and Trusting subscales than HC. The MDD group had lower scores than the SFD and HC groups on the Body Listening subscale (partial eta-squared=.18-.26). No differences with regard to Noticing of bodily sensations were found. Groups with subclinical SFD, SFD and MDD do not differ from healthy individuals in terms of actual body perception, whereas cognitive facets of interoception, such as distraction or self-regulation are differentially affected. This highlights the necessity of including specifically targeted mindfulness-based interventions