Preliminary evidence on the link between metacognitive symptoms and altered autonomic activity in Anorexia Nervosa

Abstract

Background: We aimed at investigating the relationship among self-report psychological symptoms, metacognitions, and autonomic measures in Anorexia Nervosa (AN). Methods: In a preliminary study 13 patients with AN and 13 healthy controls (HCs) participated in single-session protocol, during which Heart Rate (HR) and Skin Conductance Level (SCL) were recorded at rest, as representative measures of autonomic activation. Self-report questionnaires assessing eating disorder symptoms, state- and trait-anxiety, obsessive-compulsive symptoms and metacognitions were also administered. In a second pilot study, the same psychological measures were collected on 11 patients with AN and 12 HCs, but Heart Rate Variability (HRV) was extracted from HR, as a more adequate index of sympathetic/parasympathetic balance. Student’s t-tests for independent groups (patients vs HCs) were used to compare all of the variables and correlations were performed to test the presence of possible associations between psychological and physiological measures. Findings: Beyond the symptomatology characterising anorexic disorder, in both studies patients with AN reported more maladaptive metacognitions than HCs. As regards autonomic variables, we found a significant sympathetic hypoactivation (study 1) or even parasympathetic prevalence (study 2) in patients, which could not be ascribed to reduced BMI. Remarkably, significant correlations linked patients’ reduced sympathetic/increased parasympathetic activity to dysfunctional metacognitive dimensions. Discussion: These preliminary findings disclose a potential link between altered metacognition and altered autonomic activity, which can be capitalized in the treatment phase, by simultaneously rebalancing both levels. The concurrent use of metacognitive therapies and psychophysiological self-regulation protocols (e.g., through biofeedback procedures) could strategically strengthen the intervention efficacy.