The body image disturbance at the heart of anorexia nervosa is a false perception akin to the perceptual disorders found in schizophrenia.
The body image disturbance at the heart of anorexia nervosa is a false perception akin to the perceptual disorders found in schizophrenia. Additional psychotic features associated with eating disorders-usually transient-have been attributed to the effects of starvation and electrolyte imbalance.
Eating disorders and psychotic disorders are both characterized by distorted thoughts, overvalued ideas, depersonalization and derealization phenomena, and delusions. Moreover, auditory hallucinations, considered to be the hallmark of psychosis, can also occur in anorexia nervosa.
A basic mistrust of others-a trait that often leads to social isolation, poor therapeutic alliance, and poor treatment adherence-is common to both eating disorders and psychotic disorders. That said, family and people close to the patient have added insights otherwise not known to the clinician.
Psychotic features associated with eating disorders-usually transient-have been attributed to the effects of starvation and electrolyte imbalance.
Comorbidity between eating disorders and psychotic illness is seen more commonly in care services for psychotic disorders than in treatment programs for eating disorders, despite the fact that the self-starvation associated with some types of eating disorder can often result in psychotic symptoms. It is possible, therefore, that the treatment of psychosis (ie, with antipsychotic medication) may, in part, be responsible.
Antipsychotic doses should be kept as low as possible. Remember that positive symptoms of psychosis, which are targeted by antipsychotic medications, need not always be totally eliminated for patients to enjoy a good quality of life. The treatment target should be function, not symptoms. Attempts to eliminate all psychotic symptoms can induce anorexia nervosa, which is in many ways more dangerous than the original problem, with higher mortality than any other psychiatric disorder.
Antipsychotics are sometimes used off label for eating disorders. The reason is because clinicians find it difficult to distinguish the firm belief that one is fat (when that is clearly not the case) from a delusion.
Despite several potential explanations for the co-occurrence of eating disorders, it is possible that eating disorders and psychotic disorders are different phenotypic expressions of a similar genetic predisposition.
For more on this topic, see Eating Disorders and Psychosis, on which this slideshow is based.