Body dysmorphic disorder (BDD) has both psychotic and nonpsychotic variants, which are classified as separate disorders in DSM-IV (delusional disorder and a somatoform disorder). Despite their separate classification, available evidence indicates that BDD's delusional and nondelusional forms have many similarities (although the delusional variant appears more severe), suggesting that they may actually be the same disorder, characterized by a spectrum of insight. And contrary to what might be expected, BDD's delusional form, although classified as a psychotic disorder, appears to respond to serotonin-reuptake inhibitors alone. These and other data suggest that a dimensional view of psychosis (in particular, delusions) in these disorders may be more accurate than DSM's current categorical view. A dimensional model might also facilitate more consistent and accurate classification of other disorders that are likely characterized by a spectrum of insight, such as obsessive compulsive disorder, hypochondriasis, and anorexia nervosa. Further research is needed to better understand these classification issues, which likely have treatment implications.
Body dysmorphic disorder (BDD) inhabits a place in the psychiatric landscape where psychotic and nonpsychotic disorders meet. This disorder has both psychotic and nonpsychotic variants, which are classified as separate disorders in DSM: its nonpsychotic variant as a somatoform disorder, and its delusional variant as a psychotic disorder—a type of delusional disorder, somatic type (American Psychiatric Association, 1994). These two disorders may be double-coded, however; that is, delusional individuals may be diagnosed with both BDD and delusional disorder. While double coding is awkward, and has the drawback of diagnosing the same symptoms as two different disorders, it also reflects the possibility that BDD's delusional and nondelusional variants actually constitute the same disorder rather than being distinct.
Research on BDD, a distressing or impairing preoccupation with an imagined or slight defect in appearance, is still in its early stages. Nonetheless, this disorder's psychotic features have been of interest and the focus of research. As discussed below, BDD's delusional and nondelusional forms appear to have many similarities, raising the question of whether these forms of BDD, although classified separately in DSM-IV, may actually be the same disorder, characterized by a spectrum of insight. And contrary to what might be expected, BDD's delusional form, although classified as a psychotic disorder, appears to respond to serotonin-reuptake inhibitors (SRIs) alone. These intriguing data may shed light on psychosis in other nonschizophrenic disorders, such as anorexia nervosa and obsessive compulsive disorder (OCD), about which little is known.
In this paper I will discuss the psychotic symptoms that commonly occur in BDD, similarities and differences between BDD's delusional and nondelusional variants, and their treatment response. I will then discuss a dimensional view of psychosis as an alternative to the current categorical view, as well as DSM-IV's inconsistent classification of BDD and other nonschizophrenic disorders that have psychotic features (delusions being the primary form of psychosis in these disorders). Finally, I will consider some of the research needed to better understand these understudied classification issues, which likely have treatment implications.
