Autism Spectrum symptoms in a population of extremely undernourished patients with Anorexia Nervosa: a pilot study

Objectives Symptoms of Autism Spectrum Disorder (ASD) are overrepresented among individuals with Anorexia Nervosa (AN). We aimed to study the prevalence of ASD symptoms in extremely undernourished inpatients with AN and focus on potential cognitive and nutritional correlates. Methods We recruited prospectively all extremely undernourished patients with AN admitted to the Nutritional Care Unit of Paul Brousse Hospital over four months. ASD traits and AN psychopathology were assessed by administering the Autism Quotient (AQ) and the Eating Disorder Inventory-2 (EDI-2). Neuropsychological and bio-nutritional data were also collected. Results Among 33 participants aged 25.5 ± 9.3 (91 % females, BMI: 12.1 ± 1.4), 12 % scored above the clinical cut-off on the AQ. Independently of age and BMI, EDI-2 scores were significantly correlated with AQ-total scores (r = 0.62; p < 0.01), higher levels of cognitive rigidity (r = 0.61; p < 0.001) and sensory sensitivity alterations (r = 0.69; p < 0.01). In the cross-sectional model, the AQ-communication domain, and the GSQ-hyposensitivity scale were significant predictors (p < 0.5) of the variance in EDI-2 scores. Negative beliefs and cognitive confidence were associated with lower levels of Transthyretin (p < 0.02). Conclusions ASD traits presented high prevalence in extremely undernourished patients with AN. Despite the impact that malnutrition can have on cognitive functioning, most of these traits appear to be independent of BMI but associated with the severity of eating psychopathology; only Transthyretin was associated with dysfunctional metacognitions. These preliminary results suggest that ASD symptoms might co-occur in severe AN and require specific therapeutic interventions.