Interoceptive impairments in early-stage anorexia nervosa: exploring the impact of childhood trauma and heart rate variability

Background: Anorexia nervosa, restricting subtype (AN-R), is a severe psychiatric disorder, with abnormal interoception, autonomic nervous system disturbances, and increased exposure to childhood traumatic experiences (CTEs), frequently observed as correlates. This is the first study exploring the impact of CTEs and heart rate variability (HRV; i.e., an index reflecting parasympathetic arousal) on interoceptive accuracy (IA; i.e., the ability to track changes in bodily signals) in AN. Methods: Twenty-five patients with AN-R within a year of onset and 25 matched healthy controls were recruited. IA was assessed through the heart beat detection task. HRV was measured before and after the task. Participants also completed the Childhood Trauma Questionnaire. We performed a to detect significant differences between groups in HRV reactivity and IA, and a linear regression to test the effect of factors of interest on IA. Results: Patients with AN-R displayed significantly increased HRV reactivity and decreased IA compared to HCs. They also reported significantly more CTEs. Furthermore, childhood emotional neglect significantly predicts IA impairments. Conclusions: Although the pathway linking emotional neglect to abnormal interoception in AN-R remains to be clarified, an embodiment-informed framework may show promise in the treatment of individuals with eating disorders who experienced childhood maltreatment.