Childhood-onset pathologic skin picking: clinical characteristics and psychiatric comorbidity

Comprehensive Psychiatry 48 (2007) 388 – 393 www.elsevier.com/locate/comppsych

Childhood-onset pathologic skin picking: clinical characteristics and psychiatric comorbidity Brian L. Odlaug, Jon E. Grant4 Department of Psychiatry, University of Minnesota School of Medicine, Minneapolis, MN 55454, USA

Abstract There has been little research examining clinical correlates of childhood-onset pathologic skin picking in a sample of individuals with a primary diagnosis of pathologic skin picking. Using a sample of 40 consecutive subjects with current pathologic skin picking, we compared subjects with childhood-onset (before 10 years of age) pathologic skin picking to those with later onset on a variety of clinical measures. Symptom severity was examined by assessing time spent picking per day, intensity and frequency of thoughts and urges to pick, and social and occupational functioning. Of the 40 subjects, 19 (47.5%) reported onset of skin picking before 10 years of age. Subjects with childhoodonset had significantly longer durations of illness before receiving treatment and were more likely to pick unconsciously. Symptom severity, comorbidity, and social functioning did not differ between groups. These preliminary results suggest that although onset before 10 years of age is fairly common among people with pathologic skin picking, individuals developing this behavior earlier in life have similar clinical characteristics as those with later onset but may be less likely to seek treatment. D 2007 Elsevier Inc. All rights reserved.

1. Introduction Pathologic skin picking, also known as neurotic excoriation, compulsive skin picking, psychogenic excoriation, and dermatillomania, is clinically defined as the repetitive or compulsive picking of skin to the point of causing tissue damage. Pathologic skin picking is associated with recurrent infections, social isolation, shame and embarrassment [1], and impaired functioning [2]. Although prevalence in the general population is unknown, pathologic skin picking has estimated rates of 4% in college students [3] and 2% in dermatology clinic patients [4,5]. Pathologic skin picking appears to occur frequently in adolescent psychiatric settings (11.8% of inpatients) and often goes unrecognized [6]. Pathologic skin picking appears to have phenomenological and possibly biologic similarities to trichotillomania [7]. Research on this related disorder has found that age of onset may be associated with unique clinical features [8]. For example, childhood-onset trichotillomania often does not continue into adolescence [9], has been described often as self-limited [10], may be a more benign form of the disorder [11], usually lacks a sense of tension or relief often endorsed

by older patients, and is associated with fewer comorbid conditions [12]. Furthermore, gender distribution seems to be approximately equal in childhood onset trichotillomania [10,13], whereas adult clinical samples have demonstrated a higher female predominance [14]. A recent study found that the mean age of onset for pathologic skin picking is 12 years [15]. Previous studies investigating the clinical characteristics of pathologic skin picking, however, have failed to examine how age of onset may be associated with unique clinical characteristics of the disorder [8,16]. The goal of this study was to assess how subjects with childhood-onset pathologic skin picking (before 10 years of age) differed from subjects who had onset of pathologic skin picking at a later age. As the first study to examine age of onset in pathologic skin picking, we hypothesized that individuals with childhood-onset pathologic skin picking, like those with childhood-onset trichotillomania, would have a less severe form of the disorder and less comorbid conditions. 2. Methods 2.1. Subjects

This study was supported in part by an unrestricted educational grant from GlaxoSmithKline to Dr Grant. 4 Corresponding author. Tel.: +1 612 273 9736; fax: +1 612 273 9779. E-mail address: [email protected] (J.E. Grant). 0010-440X/$ – see front matter D 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.comppsych.2007.03.007

Forty male and female outpatients, 17 to 65 years of age, were recruited from a completed pharmacologic treatment study for pathologic skin picking [17] or from an ongoing

B.L. Odlaug, J.E. Grant / Comprehensive Psychiatry 48 (2007) 388 – 393

outpatient study examining the longitudinal course of impulse control disorders. Those subjects who did not meet criteria for one of the pharmacological studies were included in the outpatient study. All subjects who contacted us for treatment were therefore included in this database if they meet the general inclusion criteria: (1) primary diagnosis of current (past 12 months) pathologic skin picking; (2) 17 years or older; and (3) can be interviewed in person. The only exclusion criterion was the presence of an organic mental disorder or inability to understand and consent to the study. The institutional review board of the University of Minnesota approved the studies and the consent statements. All study participants provided voluntary written informed consent. All subjects had a current primary diagnosis of pathologic skin picking defined by the following criteria: (1) recurrent skin picking resulting in noticeable tissue damage; (2) preoccupation with impulses or urges to pick skin which is experienced as intrusive; (3) feelings of tension, anxiety, or agitation immediately before picking; (4) feelings of pleasure, relief, or satisfaction while picking; (5) the picking is not accounted for by another medical or mental disorder (eg, cocaine or amphetamine use disorders, scabies); and (6) the individual suffers significant distress or social or occupational impairment [2,16]. bAge of onsetQ was defined as the age at which picking behavior began even if it did not meet full criteria at that time. Because a precise clinical definition of bchildhood onsetQ is still in question, we chose onset before 10 years of age as the definition of childhood onset. 2.2. Assessments 2.2.1. Clinical characteristics All subjects underwent a semistructured interview to assess clinical characteristics of the disorder. Clinical questions assessed time spent picking per day, what percentage of the time spent picking was conscious, triggers to picking, sites of the body picked, whether the subject picked anyone else’s skin (ie, proxy picking), and whether the picking resulted in the need for antibiotic treatment. 2.2.2. Severity of pathologic skin picking Severity of picking was assessed using the Clinical Global Impression (CGI) severity scale [18]. The CGI consists of a reliable and valid 7-item Likert scale used to assess severity in clinical symptoms. The CGI severity scale ranges from 1 (bnot ill at allQ) to 7 (bamong the most extremely illQ). The Yale Brown Obsessive Compulsive Scale Modified for Neurotic Excoriation (NE-YBOCS) was also used to assess symptom severity [19,20]. The NE-YBOCS is a modification of the Yale Brown Obsessive Compulsive Scale, a reliable and valid, clinician-administered scale for obsessive compulsive disorder. This modified measure is a 10-item scale that rates picking symptoms during the last

389

7 days on a severity scale from 0 to 4 for each item (total scores range from 0 to 40 with higher scores reflecting greater illness severity). The first 5 items of the NEYBOCS examine picking urges and thoughts (time occupied with urges/thoughts, interference and distress due to urges/thoughts, resistance against and control over urges/thoughts), and items 6 to 10 examine picking behavior (time spent picking; interference and distress due to picking, ability to resist and control picking behavior). This modification of the Y-BOCS has previously been used in treatment studies of pathologic skin picking and shown good psychometric properties [19,20]. The NE-YBOCS was used in only a subset of the subjects (n = 25). In order to assess the overall psychosocial interference due to picking, the Sheehan Disability Scale (SDS) [21], a 3-question, self-report measure, was included. The 3 questions examine the degree to which picking interferes with work/school, social life, and family life/home responsibilities. Like the NE-YBOCS, the SDS was used in only a subset of the subjects (n = 25). 2.2.3. Treatment history Subjects were asked about their history of both pharmacologic and psychosocial treatments. Subjects were asked whether they sought the treatments for the symptoms of pathological skin or for some other psychiatric issue. The percentage of subjects seeking treatment was recorded. 2.2.4. Comorbid psychiatric disorders One interviewer evaluated each subject with the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I Disorders (SCID-I) [22] to assess current and lifetime comorbid disorders, and SCID-compatible modules were used to examine current and lifetime rates of impulse control disorders (pathological gambling, trichotillomania, kleptomania, pyromania, intermittent explosive disorder, compulsive buying, and compulsive sexual behavior) [23]. 2.2.5. Family history Each subject underwent a semistructured interview to examine psychiatric disorders, including impulse control disorders, pathologic skin picking and compulsive nail biting, in first-degree relatives. No relatives were interviewed. 2.2.6. Statistical analysis Subjects grouped by age of onset (childhood-onset [before 10 years of age] vs later onset) were compared on measures of sociodemographics, clinical features, clinical severity including impairment, lifetime and current rates of comorbid disorders, and family history. Between-group differences were tested using Pearson v 2, Fisher exact, t (2-tailed), or Mann-Whitney U tests. Because we performed multiple comparisons, we used an adjusted a level of P b .01; we did not adjust the a level to reflect all statistical

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B.L. Odlaug, J.E. Grant / Comprehensive Psychiatry 48 (2007) 388 – 393

comparisons because this is the first study of this topic and is therefore exploratory. 3. Results 3.1. Demographics Forty consecutive subjects (mean F SD age = 34.8 F 12.21 years; [range, 17-63]) meeting criteria for pathologic skin picking were included. Individuals with childhoodonset pathologic skin picking did not differ significantly from those with later onset on demographic variables (Table 1). The childhood onset group was 7 years younger, however, at the time of presentation. 3.2. Clinical characteristics and severity Although there were no statistical differences between groups on most clinical variables (Table 2), there was a statistical trend for subjects with childhood-onset pathologic skin picking to be less likely to pick with conscious awareness of their behavior (60.5% conscious picking in the childhood-onset group compared to 79.8% in the later-onset group) (t test = 2.086; P = .045). The remainder of the time, they were not aware of their picking until they started to bleed or someone mentioned it to them (Table 2). Seeking treatment specifically for skin picking differed between groups. Those with childhood-onset pathologic skin picking were, on a trend level, less likely to have previously sought medication treatment for neurotic excoriation (v 2 = 4.021; df = 1; P = .035). However, only 4 subjects actively sought treatment in the past. Although all 4 obtained medication treatment, one also received hypnosis, and another, habit reversal counseling. In addition, there

was a trend toward significance in assessing triggers to pick with 16 (84.2%) of the childhood-onset subjects endorsing the bfeel of the skinQ as a trigger compared to 12 (57.1%) of the later onset population (v 2 = 3.480; df = 1; P = .062). The time between pathologic skin picking symptom onset and seeking treatment differed, on a trend level, between groups. In childhood-onset pathologic skin picking, subjects reported onset of picking behavior at 5.6 years of age but did not seek treatment until 31.3 years of age, a lag time of 25.7 years. In comparison, subjects with later-onset pathologic skin picking reported behavior onset at 20.3 years of age but presented for treatment at 38.0 years of age, a difference of 17.7 years (t = 2.22; df = 38 P = .033). 3.3. Comorbidity and family history Current comorbid psychiatric illness was common in the overall sample (42.5%) but less prevalent in the childhoodonset population (31.6% compared to 52.4% for the later onset) (Table 2). The most common co-occurring disorder among those with childhood-onset pathologic skin picking was a mood disorder (22.5%). Family history data, although not significantly different between groups, showed that 55.6% of childhood-onset subjects reported having at least 1 first-degree family member with a grooming disorder (trichotillomania, pathologic skin picking, compulsive nail biting). Of the lateronset group, 52.4% endorsed the same finding (v 2 = 0.039c; df = 1; P = .843). 4. Discussion To our knowledge, this is the first study to examine how age of onset is associated with the clinical character-

Table 1 Demographics of subjects with childhood-onset (before 10 years of age) compared with later-onset pathologic skin picking Childhood onset (n = 19) Age at symptom onset Mean (F SD) (y) Age at presentation Mean (F SD) (y) range Sex (n [%]) Female Male Ethnicity (n [%]) White African American Asian American Others Marital status (n [%]) Single Married Widowed/separated/divorced Education (n [%]) High school grad or less Some College College grad or more

Later onset (n = 21)

Statistic

df

P b .001

5.6 (2.2)

20.3 (11.6)

0.568t

21.6

31.3 (9.8) 21-51

38.0 (13.5) 17-63

1.79t

38

.081

1

.451

N/A

.098

17 (89.5) 2 (10.5)

17 (81.0) 4 (19.0)

0.568c

16 (84.2) 1 (5.3) 1 (5.3) 1 (5.3)

21 (100)

11 (57.9) 7 (36.8) 1 (5.3)

7 (33.3) 13 (61.9) 1 (4.8)

2.595c

2

.273

3 (15.8) 4 (21.1) 12 (63.8)

6 (28.6) 4 (19.0) 11 (52.4)

0.837

N/A

.402

f

For statistic column: t, t test; c = v 2; f, Fisher exact test (2-sided) compared white vs nonwhite for statistical test.; z, Mann-Whitney test.

B.L. Odlaug, J.E. Grant / Comprehensive Psychiatry 48 (2007) 388 – 393

391

Table 2 Clinical characteristics of subjects with childhood-onset (before 10 years of age) compared with later-onset pathologic skin picking Childhood onset (n = 19)a Time spent picking per day (min) Mean (FSD), range 90.3 (103.6), 20-480 Percentage of total picking time that was conscious Mean (FSD), range 60.5 (33.1), 10-100 Triggers to pick (n [%]) Look of skin 3 (15.8) Feel of skin 16 (84.2) Mood 7 (36.8) Sites picked (n [%]) Face 8 (42.1) Hands/arms/feet/legs 18 (94.7) Torso 5 (26.3) Picks someone else’s skin n (%) 2 (10.5) Has needed antibiotic treatment for excoriations (n [%]) 3 (15.8) CGI severity Mean (FSD) 4.47 (.772) NE-YBOCS, total score Mean (FSD), range 18.7 (6.4), 11-30 SDS Mean (FSD), range 10.6 (6.7), 1-21 Previous treatment specifically sought for picking behavior (n [%]) Medication 0 (0) Therapy 0 (0) Previous treatment sought for psychiatric disorders (not picking) (n [%]) Medication 11 (57.9) Therapy 1 (5.3) Comorbid current disorders (n (%)) Any mood disorder 2 (10.5) Any anxiety disorder 0 (0) Any somatoform disorder 1 (5.3) Any substance use disorder 0 (0) Trichotillomania 1 (5.3) Any impulse control disorder (other than trichotillomania) 2 (10.5) Any comorbid current disorder 6 (31.6) Comorbid lifetime disorders (n [%]) Any mood disorder 3 (15.8) Any anxiety disorder 0 (0) Any somatoform disorder 1 (5.3) Any substance use disorder 0 (0) Trichotillomania 1 (5.3) Any impulse control disorder (other than trichotillomania) 2 (10.5) Any comorbid lifetime disorder 7 (36.8) At least 1 first-degree family member with a grooming disorder n (%) 10 (55.6)

Later onset (n = 21)a

Statistic

df

P

96.0 (95.9), 30-480

.755z

N/A

.450

79.8 (23.3), 30-100

2.086t

32.2

.045

5 (23.8) 12 (57.1) 7 (33.3)

f 3.480c 0.054c

N/A 1 1

.698 .062 .816

14 (66.7) 16 (76.2) 8 (38.1)

2.431c f 0.631c

1 N/A 1

.119 .186 .427

F F

N/A N/A

3 (14.3) 4 (19.0)

1.0 1.0

4.81 (.928)

1.236t

38

.224

20.4 (6.0), 10-34

0.653t

23

.520

13.5 (5.4), 5-28

1.209t

22

.240

4.021c 1.905c

1 1

.035 .168

12 (57.1) 5 (23.8)

0.002c F

1 N/A

.962 .186

7 0 3 1 3 1 11

(33.3) (0) (14.3) (4.8) (14.3) (4.8) (52.4)

f f f f f f 1.766c

N/A N/A N/A N/A N/A N/A 1

.133 1.0 .607 .607 .596 1.0 .184

9 1 3 1 3 1 13

(42.9) (4.8) (14.3) (4.8) (14.3) (4.8) (61.9)

3.480c f f f f f 2.506c

1 N/A N/A N/A N/A N/A 1

.062 1.0 .607 1.0 .607 .596 .113

11 (52.4)

0.039c

1

4 (19.04) 2 (9.52)

.843

N/A, not applicable. a Only 11 childhood- and 14 later-onset subjects completed the NE-YBOCS and SDS.

istics of pathologic skin picking. In our sample of 40 subjects with pathologic skin picking, 47.5% had onset before 10 years of age. This is higher than rates reported in samples of trichotillomania subjects where approximately 35% report onset before this age [24] or in obsessive compulsive disorder (OCD) where 1 study found 14% of subjects had onset before 10 years of age [25]. Although general sociodemographic and clinical characteristics between childhood- and later-onset pathologic skin picking were largely similar, those with childhood onset were less

likely to pick with full conscious awareness of their behavior, were more likely to wait considerable time before seeking any treatment, and were less likely to seek medication treatment. Unlike studies of trichotillomania [11], childhood-onset pathologic skin picking was not associated with a more benign form of illness or less comorbidity than later onset. In addition, although not an epidemiological study, the findings of a greater female preponderance in both childhood-onset and later-onset pathologic skin picking

392

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also appears to differ from previous findings in trichotillomania [9]. These findings are also inconsistent with findings of childhood-onset OCD, where research suggests that childhood onset is associated with a slight male predominance [26] and elevated rates of comorbid tic, anxiety, mood, and disruptive disorders [25-29]. These differences may suggest that childhood-onset pathologic skin picking has distinct neurobiologic underpinnings and may be a childhood disorder distinct from both trichotillomania and OCD. One alternative explanation for the high rates of females in both the childhood- and later-onset groups of pathologic skin pickers in this study is that attractive hands and skin may be more bexpectedQ from females and therefore make them more likely to seek treatment when they have damaged their skin. Whether similar percentages of males of all ages who pick exist undetected in the community is therefore still a possibility. Unlike many other psychiatric disorders that have a more severe form of illness associated with earlier onset [30,31], subjects in this study with childhood-onset illness did not report significantly greater social or occupational impairment at a later age. One reason for this finding is that those subjects who had dealt with the skin picking longer may have learned to cope with the disorder and possibly avoid situations in which impairment may be evident. Alternatively, it is possible that both groups had ample time to learn to cope with their behavior. Awareness of picking was significantly less in the childhood-onset subjects, although awareness of picking and automatic picking are not mutually exclusive (a phenomenological finding similar to that seen in trichotillomania) [24]; this difference in motivation to pick may have important clinical implications. Awareness of picking and the interplay between bhabitQ and motivation is a complex clinical and biologic phenomenon [32], and many individuals with pathologic skin picking begin picking unaware of the behavior and become more aware of it as time progresses. Although research has not examined whether certain treatments may preferentially work on those with more or less conscious awareness of their behavior, one might imagine that antiobsessional agents and behavioral therapies may work preferentially on those subjects with later-onset picking as they appear to have greater awareness of their picking. In addition, parents of children who manifest this behavior may need to increase their child’s awareness of their behavior if they wish to help the child better control their picking behavior. The finding that subjects with childhood-onset pathologic skin picking waited, on average, 25 years before seeking treatment is clinically important and yet not easily explained. One hypothesis is that the behavior is not particularly distressing, and therefore, individuals with the behavior have little interest in seeking treatment. Subjects in this study, however, reported significant distress associated with the behavior dating back to childhood. A second hypothesis is that these subjects suffered due to lack of

knowledge about their behavior and its treatment. Pathologic skin picking is not yet recognized by the American Psychiatric Association as a psychiatric disorder, and many subjects told us that they did not know this behavior was a psychiatric illness or that treatment was available. Because the lack of awareness of pathologic skin picking may have been more pronounced years ago, this may have resulted in a more poorly managed form of the illness in those with childhood-onset pathologic skin picking. More than half of the subjects (52.5%) reported at least 1 first-degree family member with at least 1 grooming disorder. No control group was examined, but it seems very unlikely that such high rates would be found for relatives of nonaffected individuals. These rates of familial grooming disorders may lend further support for the genetic basis of pathologic grooming behaviors in some individuals [33-36]. Because of the small sample size surveyed for this project, a larger compilation of individuals with pathologic skin picking and their families would need to be obtained to validate this hypothesis. Although this study is the first to assess age of onset in pathologic skin picking, it still suffers from several limitations. First, this is a retrospective study with childhood onset determined later in life and thereby suffers from possible recall bias. Future research should explore age of onset using a longitudinal design. Second, this study included people who were seeking treatment for pathologic skin picking. Therefore, it is unclear how generalizable our results are to individuals with pathologic skin picking in the community. Third, this study involves a small sample size, and any conclusions based on this sample must therefore be made cautiously. Fourth, bchildhood onsetQ continues to be an ill-defined term. Studies of obsessive-compulsive spectrum disorders demonstrate that varying ages (eg, before 10, 12, or 16 years) have been used to define bearly onset,Q and whether there are advantages in examining childhood vs adolescent onset in skin picking still await examination. Finally, our findings concerning family history were not a result of direct interviews of family members, and there was no control group for comparison. Our results may therefore either over- or underestimate the number of first-degree relatives with grooming disorders. In summary, the age of onset in individuals with pathologic skin picking appears to be associated with certain distinct clinical features. Recognition of picking behavior by parents of young children may be helpful in the overall treatment of the illness at a young age. This study also illustrates the lifelong severity of pathologic skin picking, regardless of age of onset. Clinicians need to screen and educate their patients about pathologic skin picking and possible treatment options [17,19,20,37-39]. References [1] Swedo SE, Rapoport J. Annotation: trichotillomania. J Clin Psychol 1991;32:401 - 9.

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