Clinical characteristics and medical complications of pathologic skin picking

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General Hospital Psychiatry 30 (2008) 61 – 66

Clinical characteristics and medical complications of pathologic skin picking Brian L. Odlaug, B.A., Jon E. Grant, J.D., M.D., M.P.H.⁎ Department of Psychiatry, University of Minnesota School of Medicine, Minneapolis, MN 55454, USA Received 25 June 2007; accepted 30 July 2007

Abstract Objective: This study sought to detail the phenomenology and medical consequences of pathologic skin picking (PSP). Method: Sixty subjects (11.7% males) with PSP (mean±S.D.=33.7±11.6 years) were assessed. Subjects seen in a pharmacological study as well as those from an ongoing outpatient longitudinal study comprised this sample. Subjects were assessed for current and lifetime psychiatric comorbidity (using the Structured Clinical Interview for DSM-IV Axis I Disorders), clinical severity (using the Clinical Global Impression — Severity scale) and psychosocial interference due to picking (using the Sheehan Disability Scale). Clinical characteristic data, including time spent picking per day, sites picked and medical complications directly resulting from skin picking behavior, as well as family history, were also obtained. Results: The mean age (±S.D.) of onset for PSP was 12.3±9.6 years. The face was the most common area picked. Subjects reported picking a mean of 107.6 min each day. Scarring, ulcerations and infections were common. Few had ever sought psychiatric treatment for their behavior. Current comorbid Axis I psychiatric conditions were found in 38.3% of the sample. Trichotillomania (36.7%), compulsive nail biting (26.7%), depressive disorder (16.7%) and obsessive–compulsive disorder (15%) were the most common current comorbid conditions. Conclusion: PSP appears to be time consuming and frequently associated with medical complications. Research is needed to optimize patient care for individuals with this behavior. © 2008 Elsevier Inc. All rights reserved. Keywords: Pathologic skin picking; Neurotic excoriation; Psychogenic excoriation

1. Introduction Pathologic skin picking (PSP), also referred to as neurotic excoriation or psychogenic excoriation, is a condition characterized by repetitive or compulsive picking of skin to the point of causing tissue damage. Individuals suffering from PSP report significant distress and psychosocial impairment, including occupational and marital difficulties [1–3]. Prevalence rates of PSP in the general population are unknown, but studies have found that the behavior occurs in 4% of college students [4], 2% of dermatology patients [5,6], 11.8% of adolescent psychiatric inpatients [7] and 44.9% of individuals with body dysmorphic disorder (BDD) [8]. Recent studies have also detailed the relationship between PSP and obsessive–compulsive disorder (OCD), finding ⁎ Corresponding author. Tel.: +1 612 273 9736; fax: +1 612 273 9779. E-mail address: [email protected] (J.E. Grant). 0163-8343/$ – see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.genhosppsych.2007.07.009

elevated rates of PSP in patients with OCD and their firstdegree relatives [9,10]. The majority of individuals seeking treatment for PSP are female [11]. Although PSP generally has its onset in adolescence, it may occur at any age [4,12,13]. In fact, the onset of PSP often begins with a dermatological condition such as acne, eczema or psoriasis [14]. The picking behavior may result in significant tissue damage and scarring, sometimes even warranting surgery [12], and, in rare cases, can be life threatening [15]. Individuals with PSP rarely seek dermatological or psychiatric treatment due to embarrassment [14] or the mistaken belief that their condition is untreatable [16]. In a study of 31 patients with PSP, only 14 (45%) had ever sought treatment and only 6 of the 31 had ever received dermatological treatment despite the infections and “deep craters” their picking behavior often resulted in [14]. Research on PSP has been limited by small sample sizes, with little attention given to the medical consequences of

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picking behavior. Because there have been few systematic studies of a series of rigorously diagnosed individuals with PSP, the present study's purpose was to construct a detailed demographic, phenomenological and medical picture of individuals meeting proposed criteria for PSP. An understanding of the characteristics and medical problems of individuals suffering from this behavior may have clinical importance. Clinicians not only need to recognize the emotional and psychosocial impact of picking to provide appropriate mental health care but also need to be aware of possible medical sequelae of picking so that appropriate interventions may be made. 2. Methods 2.1. Subjects Sixty male and female outpatients, aged 17–63 years, were recruited from a completed pharmacological treatment study for PSP [16] and from an ongoing outpatient study examining the longitudinal course of impulse control disorders. Subjects for the pharmacological treatment study (n=31) were recruited through newspaper advertising and by posting flyers around the Minneapolis/Saint Paul metro area. The outpatient study sample (n=29) was recruited through flyers placed in a psychiatry clinic or physician referral. No individuals refused to participate in either study. Subjects were included in this database if they met the general inclusion criteria, that is, if they (a) have a primary diagnosis of current (past 12 months) PSP, (b) are 17 years or older and (c) could 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. All subjects had a current primary diagnosis of PSP defined by the following criteria (note: Criteria c and d have been added to previously proposed criteria [17] to reflect the criteria of trichotillomania and to limit more mild forms of picking from being pathologized): (a) recurrent skin picking resulting in noticeable tissue damage; (b) preoccupation with impulses or urges to pick skin, which is experienced as intrusive; (c) feelings of tension, anxiety or agitation immediately prior to picking; (d) feelings of pleasure, relief or satisfaction while picking; (e) the picking is not accounted for by another medical or mental disorder (e.g., cocaine or amphetamine use disorders, scabies); and (f) the individual suffers significant distress or social or occupational impairment. All research procedures were approved by the Institutional Review Board of the University of Minnesota, and all research subjects provided written informed consent prior to treatment. 2.2. Assessments 2.2.1. Clinical characteristics All subjects underwent a semistructured interview to assess clinical characteristics of the behavior. 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 (i.e., proxy picking) and whether the picking resulted in medical complications. All clinical interviews were conducted by the same clinician (J.E.G.) to ensure rating consistency and were done in an outpatient setting. 2.2.2. Severity of PSP Severity of picking was assessed using the Clinical Global Impression (CGI) — Severity scale [18]. The CGI consists of a seven-item Likert scale used to assess severity in clinical symptoms. Although not tested specifically in PSP, the CGI has demonstrated excellent reliability and validity in a wide range of psychiatric disorders. The Severity scale of the CGI ranges from 1 (not ill at all) to 7 (among the most extremely ill). In order to assess the overall psychosocial interference due to picking, we included the Sheehan Disability Scale (SDS) [19], a three-question self-report measure. The three questions examine the degree to which picking interferes with work/school, social life and family life/home responsibilities. Each item uses an 11-point Likert scale with scores ranging from 0 (no impairment) to 10 (extreme impairment). Greater impairment is therefore defined by higher scores, with total scores ranging from 0 to 30. The SDS was used in only those subjects who consented to the pharmacological treatment study (n=31) [16]. 2.2.3. Comorbid psychiatric disorders Each subject underwent the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) [20], which was administered by one clinician (J.E.G.), to assess current and lifetime comorbid disorders, and SCID-compatible modules were used to examine current and lifetime rates of impulse control disorders (pathologic gambling, trichotillomania, kleptomania, pyromania, intermittent explosive disorder, compulsive buying and compulsive sexual behavior). 2.2.4. Family history Each subject underwent a semistructured interview using the SCID-I and SCID-compatible modules [20] to examine psychiatric disorders, including impulse control disorders, PSP and hair pulling, in first-degree relatives. All psychiatric disorders that were included for the subject were also included in this interview. No relatives were interviewed directly for this study. 3. Results 3.1. Demographics Sixty consecutive subjects [n=7 (11.7%) males] with current PSP were studied. At the time of presentation, the age of the 60 subjects ranged from 17 to 63 years (mean±S.D.=33.7±11.6). The sample included 55 (91.7%)

B.L. Odlaug, J.E. Grant / General Hospital Psychiatry 30 (2008) 61–66 Table 1 Clinical characteristics, family history and psychiatric comorbidity of 60 individuals with PSP Characteristic

Value

Age of onset (years), mean (±S.D.) Time spent picking per day (min), mean (±S.D.) [range] Percentage of total picking time that was conscious, mean (±S.D.) [range] Triggers to picking, n (%) Feel Sight Boredom/Downtime Stress Mood Tired Sites picked, n (%) Head/Face Legs/Feet Arms Torso Hands/Fingers Number of sites picked, mean (±S.D.) [range] No. of places picked, n (%) 1 2 3 4 N4 Items used to pick skin Fingernails Tweezers Knives/Pins/Other objects Picks other people's skin, n (%) Previously sought treatment for picking, n (%) Therapy Medication CGI severity, mean (±S.D.) SDS (n=31), mean (±S.D.) [range] At least one first-degree family member with: PSP, n (%) Trichotillomania, n (%) Subjects with at least one first-degree family member with either trichotillomania or PSP, n (%)

12.3 (9.6) 107.6 (108.7) [20–480] 78.1 (27.0) [10–100]

33 (55.0) 16 (26.7) 15 (25.0) 12 (20.0) 5 (8.3) 3 (5.0) 36 (60.0) 20 (33.3) 18 (30.0) 14 (23.3) 13 (21.7) 2.28 (1.21) [1–7]

19 (31.7) 18 (30.0) 15 (25.0) 3 (5.0) 5 (8.3) 59 (98.3) 17 (28.3) 8 (13.3) 7 (11.7)

11 (18.3) 8 (13.3) 4.7 (0.9) 12.1 (6.3) [0–28]

17 (28.3) 6 (10.0) 22 (36.7)

Caucasians, 3 (5.0%) Asian Americans and 2 (3.3%) African Americans. Of the 60 subjects with PSP, 13 (21.7%) were high school graduates, 10 (16.6%) had some college or trade school education, 28 (46.7%) were college graduates and 9 (15.0) had pursued education beyond college. Thirty-two (53.3%) were single, 25 (41.7%) were married and 3 (5.0%) were divorced or separated. 3.2. Clinical characteristics The clinical characteristics are presented in Table 1. The reported mean age (±S.D.) of onset of PSP was 12.3±9.6

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years (range=3–49). Individuals picked with full awareness of their behavior the majority of time (78.1%), and clear triggers, such as the sight or feel of the skin, usually precipitated the picking. The face was the area most commonly picked, and face picking resulted in significant distress and embarrassment because of the difficulty hiding the tissue damage. The majority of subjects (68.8%) picked from more than one area and often reported that they would switch areas in order to allow an area to heal. Subjects were generally quite ill. Subjects reported picking a mean (±S.D.) of 107.6±108.7 min each day, with some subjects spending 6–8 h each day. Mean (±S.D.) CGI scores (4.7±0.9) denote marked severity of illness. The level of social and occupational dysfunction (as reflected in the SDS scores), however, was only mild in severity (12.1±6.3). 3.3. Comorbidity Table 2 summarizes comorbidity results for Axis I disorders. Twenty-three (38.3%) subjects reported symptoms consistent with a current Axis I disorder, and 34 (56.7%) reported at least one lifetime Axis I disorder. Although trichotillomania was the most common current and lifetime comorbid disorder (36.7% and 38.3%, respectively), comorbidity with other impulse control disorders was infrequent (1.6% current and 3.3% lifetime). Comorbid OCD was fairly common (15.0% current and 16.7% lifetime), but a similar disorder, BDD, was uncommon in this sample (5.0% current and 5.0% lifetime). 3.4. Family history Twenty-four subjects (40.0%) had at least one first-degree relative with a psychiatric disorder. The most common were the following: 17 (28.3%) reported having at least one firstdegree relative with picking behavior, 12 (20.0%) reported at

Table 2 Current and lifetime psychiatric comorbidity of 60 individuals with PSP Comorbid disorders

Current, n (%)

Lifetime, n (%)

Major depressive disorder Depressive disorder NOS Any bipolar spectrum disorder Social phobia OCD Any substance use disorder Attention-deficit/ hyperactivity disorder Any somatoform disorder (except BDD) BDD Any impulse control disorder (except trichotillomania) Trichotillomania Compulsive nail biting Any eating disorder Any psychotic disorder Any current comorbid disorder

9 (15.0) 1 (1.6) 4 (6.7) 2 (3.3) 9 (15.0) 1 (1.6) 4 (6.7)

19 (31.7) 1 (1.6) 4 (6.7) 2 (3.3) 10 (16.7) 2 (3.3) 4 (6.7)

0

0

3 (5.0) 1 (1.6)

3 (5.0) 2 (3.3)

22 (36.7) 16 (26.7) 1 (1.6) 0 23 (38.3)

23 (38.3) 19 (31.7) 2 (3.3) 0 34 (56.7)

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least one relative with a substance use disorder and 11 (18.3%) reported a relative suffering from depression. 3.5. Medical consequences Table 3 presents the medical consequences of PSP. All subjects had noticeable excoriations, and 17 (28.3%) had more severe ulcerations, at the initial visit. Scarring from previous picking was noted in 27 (45.0%) subjects. Scarring and ulcerations ultimately led 7 (25.9%) of those with scarring to undergo laser therapy or dermabrasion for cosmetic reasons. Although the majority of subjects used their fingernails to pick, 17 (28.3%) used tweezers and 8 (13.3%) used knives or pins to pick. None of the subjects who used these utensils sterilized them prior to use. Infections from picking were not uncommon. In fact, 35% of subjects had experienced an infection that required oral, topical or intravenous antibiotics. In the most severe cases, two subjects required skin grafting due to their inability to stop picking. Both cases of skin grafting required multiple grafts because the subjects could not stop picking the area of the graft. 4. Discussion To our knowledge, this is the first study to examine the clinical characteristics and medical complications of a large sample of individuals suffering from PSP. This is also a fairly broad sample of individuals with this disorder (our study had very broad inclusion/exclusion criteria), which may increase the generalizability of the results. The results demonstrate that PSP is a pathologic behavior that is time consuming, causes significant distress and often leads to serious medical complications. PSP is currently classified in DSM-IV-TR as an “impulse control disorder not otherwise specified” [21]. Although there exists some controversy regarding the most precise categorization of this behavior, this study's comorbidity data

Table 3 Medical consequences of PSP Medical consequence

n (%)

Linear erosions/excoriations from picking noticeable on examination Ulcerations from picking noticeable on examination Notable scarring due to tissue damage from picking Underwent laser therapy or dermabrasion for scarring a Required oral or topical antibiotic treatment due to infection from picking Required intravenous antibiotic treatment due to bacteremia/septicemia from picking Required skin grafts due to tissue damage from picking

60 (100)

a

Of the 27 subjects who had scarring

17 (28.3) 27 (45.0) 7 (25.9) 18 (30.0) 3 (5.0) 2 (3.0)

support a possible link between PSP and trichotillomania and compulsive nail biting but not other impulse control disorders such as pathologic gambling or kleptomania. Rates of trichotillomania in this study (38.3% lifetime and 36.7% current) are notably higher than rates found in the general population (1.0–2.5%) [22,23]. Similarly, nail biting was common in this study (current rate of 26.7% and lifetime rate of 31.7%), with rates much higher than the 6.4% current prevalence rate found in one study of college students [24]. Although PSP has clear similarities to trichotillomania and nail biting [11], its relationship to other obsessive– compulsive spectrum disorders remains unclear. Studies of OCD have consistently found elevated rates of comorbid PSP among subjects with OCD [25–29], and there has been evidence of a possible genetic link between PSP and subgroups of OCD [9,10,30]. This study found that rates of OCD were seven to eight times greater in PSP than in the population at large (2–3%) [31,32], further supporting a link between these disorders. The relationship of PSP to BDD (a disorder with phenomenological links to OCD) appears more complicated. A previous study found that almost one half (44.9%) of BDD subjects engage in skinpicking behavior at some point in their lives [8]. Rates of BDD in this sample of PSP subjects, however, were only 5% for both current and lifetime comorbidity. This raises questions of whether picking behavior may be a symptom of multiple disorders and whether different neurobiological and genetic underpinning may all give rise to the symptom of repetitive picking. This study found that medical complications are frequent in individuals with PSP. Approximately one third of subjects required antibiotic treatment due to their picking. This finding suggests that clinicians should carefully screen for picking behavior as patients are unlikely to volunteer the information without being asked. In addition, when picking is acknowledged, clinicians must perform physical examinations of their patients to assess the extent and severity of picking. Infections often go unnoticed and untreated when the picking is not restricted to the face. When picking is severe, appropriate referrals and collaboration with medical internists may be warranted. One health concern with these subjects, however, is that the longitudinal course of PSP remains unknown. Therefore, there is the possibility that those who have not yet caused ulcerations or needed antibiotic treatment may require such treatment in the future. In fact, many of the subjects reported that their picking behavior had initially been less frequent but that the intensity and frequency of their behavior had increased over time. In such a small sample, however, a thorough understanding of the course of PSP is not possible. These findings emphasize the importance of studying the course of PSP in order to optimize prevention and treatment strategies. This study suffers from several limitations. First, this sample was composed only of individuals seeking treatment

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(either therapy or medication). The extent to which these results generalize to the larger population of people with PSP warrants future study. Future studies using a control group of patients with a range of psychiatric disorders would be useful in determining if comorbid psychiatric illness is more prevalent in the PSP population. Second, the medical information was gathered retrospectively with no corroboration from medical records. Therefore, this information may suffer from possible recall bias and underestimation of medical complications. Third, although subjects were asked extensively about family history, no interviews were conducted with family members and no control groups were used. Nonetheless, the inclusion/exclusion criteria of the study were fairly broad (inclusion of those who did or did not meet criteria for treatment studies) and used both selfreport and interviewer-administered measures with strong psychometric properties. Large phenomenological studies are needed to elucidate the clinical characteristics, course and medical complications of PSP. As promising advances have been made in the treatment of PSP [16,33,34], early detection and intervention are imperative. Just as research has provided greater information on the neurobiology and treatment of other psychiatric disorders, neuroimaging, genetics and clinical trials will be needed to identify the pathophysiology of, and treatment for, this behavior. Acknowledgments This research was supported in part by a Career Development Award (K23 MH069754-01A1) to Dr. Grant and by NIDA (R01 DA019039). Part of this research sample was also supported by an unrestricted educational grant from GlaxoSmithKline to Dr. Grant. Dr. Grant received no honorarium and does not have any other financial interest in GlaxoSmithKline. References [1] Swedo SE, Rapoport J. Annotation: trichotillomania. J Clin Psychol 1991;32:401–9. [2] Arnold LM, Auchenbach MB, McElroy SL. Psychogenic excoriation: clinical features, proposed diagnostic criteria, epidemiology and approaches to treatment. CNS Drugs 2001;15(5):351–9. [3] Flessner CA, Woods DW. Phenomenological characteristics, social problems, and the economic impact associated with chronic skin picking. Behav Modif 2006;30:944–63. [4] Keuthen NJ, Deckersbach T, Wilhelm S, et al. Repetitive skin picking in a student population and comparison with a sample of self-injurious skin pickers. Psychosomatics 2000;41(3):210–5. [5] Griesemer RD. Emotionally triggered disease in a dermatologic practice. Psychiatr Ann 1978;8:407–12. [6] Gupta MA, Gupta AK, Haberman HF. The self-inflicted dermatoses: a critical review. Gen Hosp Psychiatry 1987;9:45–52. [7] Grant JE, Williams KA, Potenza MN. Impulse control disorders in adolescent psychiatric inpatients: co-occurring disorders and sex differences. J Clin Psychiatry 2007;68(10):1584–92.

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