Body dysmorphic disorder (BDD) is an impairing and relatively common disorder that has high comorbidity with certain Axis I disorders. However, the longitudinal associations between BDD and comorbid disorders have not previously been examined. Such information may shed light on the nature of BDD’s relationship to putative “near-neighbor” disorders, such as major depression, obsessive–compulsive disorder (OCD), and social phobia. This study examined time-varying associations between BDD and these comorbid disorders in 161 participants over 1–3 years of follow-up in the first prospective longitudinal study of the course of BDD. We found that BDD had significant longitudinal associations with major depression – that is, change in the status of BDD and major depression was closely linked in time, with improvement in major depression predicting BDD remission, and, conversely, improvement in BDD predicting depression remission. We also found that improvement in OCD predicted BDD remission, but that BDD improvement did not predict OCD remission. No significant longitudinal associations were found for BDD and social phobia (although the results for analyses of OCD and social phobia were less numerically stable). These findings suggest (but do not prove) that BDD may be etiologically linked to major depression and OCD, i.e., that BDD may be a member of both the putative OCD spectrum and the affective spectrum. However, BDD does not appear to simply be a symptom of these comorbid disorders, as BDD symptoms persisted in a sizable proportion of subjects who remitted from these comorbid disorders. Additional studies are needed to elucidate the nature of BDD’s relationship to commonly co-occurring disorders, as this issue has important theoretical and clinical implications.
Body dysmorphic disorder is a relatively common somatoform disorder, affecting an estimated 0.7–1.1% of the United States population (Bienvenu et al., 2000 and Otto et al., 2001). BDD is also a severe disorder, with studies finding high rates of suicidal ideation and suicide attempts, marked impairment in social and academic/occupational functioning, and very poor quality of life (Phillips, 2001). However, BDD has been systematically studied for little more than a decade, and little is known about the nature of its relationship to putative “near-neighbor” disorders, such as major depression, obsessive–compulsive disorder (OCD), and social phobia.
Cross-sectional studies have generally found high comorbidity between BDD and these disorders, although findings have varied somewhat across studies. Most studies have found that major depression is the most common comorbid disorder in patients with BDD, with lifetime prevalence ranging from 36% of 50 subjects (Veale et al., 1996) to 76% of 293 subjects (Gunstad and Phillips, 2003). In the largest study (n = 293), major depression was more than twice as common as any other Axis I disorder ( Gunstad and Phillips, 2003). Conversely, although findings have varied, some studies have found a high prevalence of BDD among patients with major depression, especially the atypical subtype. Two studies both found that 14% of patients with atypical major depression had comorbid BDD ( Nierenberg et al., 2002 and Phillips et al., 1996), and another study found a rate of 42% ( Perugi et al., 1998). Based on BDD’s high comorbidity with depression, and its response to antidepressants (SRIs specifically), BDD has been hypothesized to be related to affective disorders ( Phillips et al., 1995). However, BDD and depression have also been noted to have important differences, suggesting that BDD is not simply a symptom of depression ( Phillips, 1999). For example, BDD is characterized by prominent obsessions and compulsive behaviors, and it appears to respond to SRIs but not to non-SRI antidepressants ( Hollander et al., 1999, Hollander et al., 1994 and Phillips, 2001). In addition, clinical observations suggest that depressive symptoms in BDD patients often appear to be “secondary” to the distress and demoralization that BDD often causes. However, BDD’s relationship to depression has not been investigated and remains unclear.
