Pathways to orthorexia nervosa: a case series discussion.

BACKGROUND: Orthorexia nervosa (ON) has gained increasing interest in the last 2 decades. Although a consensus on the diagnostic boundaries of ON has not yet been reached, there is some evidence for an overlap with eating disorders, obsessive-compulsive disorder, and psychotic disorder. Most of the knowledge about ON has emerged from studies of non-clinical and at-risk populations and is focused on differential diagnosis; therefore, further clinical studies are needed to better outline the ON phenomenon in a real-life setting. OBJECTIVE: This case series aims at describing clinical cases that developed symptoms suggestive of ON after being diagnosed with a prior psychiatric disorder and then discussing them in light of possible clinical pathways. METHODS: Four women consecutively admitted to an outpatient unit for the treatment of eating disorders were diagnosed with ON through a clinical interview, according to Dunn and Bratman's criteria and self-administered questionnaire assessment (ORTO-15), and were considered to be eligible for this case series study. Psychiatric anamnestic data were collected retrospectively. RESULTS: The anamnesis revealed that all patients were previously diagnosed with a psychiatric disorder (i.e. obsessive-compulsive disorder, bulimia nervosa, illness anxiety disorder, and psychotic disorder) before developing ON. CONCLUSION: Past literature focused on differential diagnosis between ON and other psychiatric disorders. This is the first description of clinical cases in a real-life setting that started with different psychiatric disorders and later developed symptoms suggestive of ON. These cases have generated a new research question on the possibility that different psychiatric disorders may associate with a later onset of ON. LEVEL OF EVIDENCE: Level V, descriptive study.