The main feature of body dysmorphic disorder (BDD) is impairing preoccupation with a physical defect that appears slight to others. Previously, its delusional and nondelusional variants were sorted in two separate categories, but owing to new data suggesting that there are more similitudes than differences between them, DSM-5 now classifies both as levels of insight of the same disorder.

To enunciate the similarities and differences between the two variants of BDD.

To better understand the features and comorbidity of BDD, so as to improve its management and treatment.

Taking DSM-5 and DSM-IV-TR as a reference, we have made a bibliographic search in MEDLINE (PubMed), reviewing articles no older than 5 years that fit into the following keywords: body dysmorphic disorder, delusions, comorbidity, DSM-IV, DSM-5.

Both the delusional and nondelusional form presented many similarities in different validators, which include family and personal history, pathophysiology, core symptoms, comorbidity, course and response to pharmacotherapy.

The new classification of delusional and nondelusional forms of BDD as levels of insight of the same disorder, which places them closer to the obsessive-compulsive spectrum than to the psychotic one, not only improves treatment options, but also reinforces the theory that delusions are not exclusive of psychotic disorders, setting a precedent for the understanding and classification of other disorders with delusional/nondelusional symptoms.

The authors have not supplied their declaration of competing interest.