Ankie Roedelof^1,2, Danielle Jacobs¹, Nicole van Bezouw¹, Martine DeMilliano¹, Claudia Simon^1,2, Machteld Marcelis^1,2, 

1 GGzE Eindhoven
2 Department of Psychiatry and Neuropsychology, MHENS, Maastricht University

Keywords 
psychotic experiences, eating disorders, experience sampling method. 

Rationale 
Body image disturbance and inner anorexic voices occur in anorexia nervosa as well as in bulimia nervosa. There is some evidence that in a subgroup of patients these experiences are respectively (subclinical) delusional and hallucinatory in nature. This study examines the transdiagnostic role of psychotic features in patients with eating disorder.

Objective 
We examined i) whether patients with eating disorders have increased levels of ‘general’ (not eating disorder related) (sub)clinical psychotic experiences compared to controls, ii) whether body image disturbance and anorexic voice reach psychotic levels, and ii) whether ‘general’ (sub)clinical psychotic experiences or (sub)clinical body image delusion / hallucinatory anorexic voice are associated with negative affect (NA) and sleeping behavior? 

Design 
A cross-sectional observational experience sampling study (ESM) with 50 female individuals with eating disorders (anorexia nervosa & bulimia nervosa, age 15-25) and 50 healthy controls was conducted. Data were analysed with multilevel-regression analyses.

Results 
The preliminary results (on N=14 patients, N=16 controls; data collection is still ongoing) show that patients with eating disorders have significant more ‘general’ psychotic experiences than controls. In patients, (sub)clinical body image delusional (but not (sub)clinical hallucinatory voice) experiences, were more frequently observed than in controls. NA in patients was positively associated with ‘general’ delusional and hallucinatory experiences (the latter not significant). In patients, quality of sleep and awakening during the night were significantly worse than in controls and associated with ‘general’ (sub)clinical delusional (but not hallucinatory) experiences. No associations were present between the (sub)clinical psychotic core-symptoms of eating disorder and NA or sleep.

Conclusions
Patients with eating disorders may have higher than average vulnerability for (subclinical) psychosis associated with affect and sleep, suggesting that a transdiagnostic approach in eating disorder may benefit from further research.

References
Konstantakopoulos, G., et al. (2012), Espeset, J.E.M.S., et al. (2011). Pugh, M., et al. (2016). Abdou, t.a., et al. (2018).