In this study, we determined the prevalence of PSP in 176 individuals with current DSM-IV
BDD. To our knowledge, this is the largest and most broadly ascertained sample of individuals with BDD to have been studied. Because the current sample was ascertained from a wide variety of sources and because one third was not currently receiving mental health treatment, these results may be broadly generalizable. Of BDD subjects in this study, 44.9% had lifetime PSP and 36.9% had current PSP. The prevalence of PSP found in this study is slightly higher than that found in previous samples of BDD subjects (27–33%) [7
] and is notably higher than the prevalence found in subjects with OCD (8.9%, lifetime; 7.8%, current) [25
], in college students (2.7–3.8%) [1
] or in dermatology patients (2%) [26
]. The high prevalence of PSP in individuals with BDD and its association with disability due to BDD suggest that clinicians should carefully screen BDD patients for skin picking.
BDD patients may have obvious and noticeable skin defects due to their picking, especially if they pick their skin for hours in a day and use sharp implements such as needles or knives [7
]. Although the results of the picking may produce an appearance problem that exceeds an “imagined or [a] slight defect in appearance” which DSM-IV
], these patients still qualify for the diagnosis of BDD because, when they do not pick, their skin appears relatively normal. Many skin pickers use makeup to camouflage minimal skin lesions or more obvious skin lesions that may result from picking. The finding that skin pickers were somewhat (but not significantly) less likely than nonpickers to have minimal or actual skin defects may reflect the use of camouflaging with makeup by the skin-picking group.
Clinicians should be aware that the purpose of picking in BDD is to improve the skin’s appearance, not to intentionally self-mutilate. However, this behavior is typically characterized by very strong urges that are difficult to resist or control, and it may consume hours in a day [7
]. The resulting skin damage may be assumed to reflect intentional self-mutilation, even though it does not. In more severe cases, patients presenting with PSP should receive a thorough physical examination by an internist to assess for possible medical complications (e.g., infection).
This study suggests that PSP is common in individuals with BDD. In addition, we found that trichotillomania, a grooming disorder that shares phenomenological similarities with PSP [6
], was more common in BDD subjects with PSP. This elevated rate of co-occurrence of trichotillomania in a subset of individuals with BDD may support some shared underlying neurobiological correlates and genetic factors [27
]. In fact, one previous study found significantly higher rates of “grooming disorders” (pathological nail biting, PSP, trichotillomania or impulse control disorder not otherwise specified), as well as BDD, in first-degree relatives of OCD probands than in first-degree relatives of control subjects, suggesting that BDD may be related to grooming disorders, as well as to OCD [27
Subjects with BDD and PSP were not more severely ill or functionally impaired (contrary to our hypothesis) than BDD subjects without skin picking, except that the skin-picking group was more likely to be receiving disability payments for BDD. Both groups of BDD subjects had very poor overall functioning, and the presence of PSP had little effect on these measures. Once PSP has been identified as a symptom of BDD, it is important to focus on it during treatment, especially because we found that patients who pick their skin consider skin picking their most problematic BDD behavior.
Our results suggest that individuals with BDD who pick their skin are as likely as those who do not pick their skin to respond to SRIs as well [28
]. This study examined improvement in overall BDD, not skin picking per se, however; in addition, treatment response was determined retrospectively, which may be subject to error. Given that SRIs have demonstrated some promise in the treatment of PSP unrelated to BDD [1
], future studies will need to prospectively examine the response of PSP in BDD patients to SRIs. Studies are also needed to determine whether psychotherapy — and what type of therapy — is efficacious for PSP when it is a symptom of BDD. Based on clinical experience, it is recommended that PSP be treated with habit reversal — the behavioral treatment of choice for trichotillomania [29
]. This differs from treatment recommendations for other BDD symptoms (with the possible exception of hair pulling) for which other cognitive and behavioral techniques are recommended. This study also demonstrates that many BDD patients with PSP instead seek and receive a variety of treatments from dermatologists. Although such treatment appears to rarely be effective in reducing overall BDD symptoms [30
], future studies are needed to prospectively examine outcome with dermatological interventions. Clinical experience suggests that dermatologic treatment is not effective for PSP but may be necessary when patients damage their skin, especially when this behavior causes infection or requires sutures [5
This study has a number of limitations. One limitation is that it is unclear how generalizable our results are to individuals with BDD in the community. Nonetheless, our sample is broader than those in previous BDD studies in that the study inclusion/exclusion criteria were very broad and a substantial proportion of participants were not currently receiving psychiatric treatment. One major limitation of the current study is that data on the severity of PSP were not collected. Future studies should include specific measures assessing PSP in subjects with BDD. Other limitations are that treatment was examined retrospectively and that multiple analyses were performed without statistical corrections. The strengths of the study include the fact that subjects were well characterized, the sample was fairly large and both self-report and interviewer-administered measures with strong psychometric properties and established norms were used.
In conclusion, these results suggest that PSP is common in individuals with BDD. Additional research on this topic is needed, including studies that further elucidate the phenomenological features of PSP as a symptom of BDD, as well as the functional relationship between BDD obsessions and skin picking (e.g., whether skin picking reduces anxiety caused by BDD obsessions) [31
]. Also needed are larger prevalence studies, larger studies of clinical correlates of PSP in BDD and studies examining the effectiveness of mental health treatments and nonmental health (e.g., dermatologic) treatment for this distressing and problematic behavior.