Somatic symptom distress is not related to cardioceptive accuracy

(Cardiac) interoception was long considered a key mechanism behind symptom perception in persistent somatic symptoms (PSS). In this study, we aimed to extend earlier findings to clarify this potential interoceptive mechanisms of PSS. A cross-sectional sample of 251 participants (23.1% with self-reported functional somatic syndrome) completed a laboratory study with two cardioceptive accuracy tasks (Schandry task and a new cardiac signal detection task) and multiple questionnaires. Somatic symptom distress and associated constructs were assessed with the PHQ-15, as well as with a novel multidimensional questionnaire measure (HiTOP-SF1) derived from the somatoform spectrum of the Hierarchical Taxonomy of Psychopathology (HiTOP). Correlations (frequentist and Bayesian) and structural equation modelling (SEM) helped further investigate the interplay between these variables. There were no significant correlations between measures of interoception and somatic symptom distress. Self-report and behavioral cardioceptive accuracy measures did not correlate significantly. No significant covariances emerged between diagnostic tools and cardioceptive accuracy; Bayesian analyses supported the lack of association between interoception and symptom perception. Cardiac interoception (specifically cardioceptive accuracy) unlikely represents a key mechanism in PSS etiology. We recommend investigating other factors in PSS.