General Hospital Psychiatry xxx (2014) xxx–xxx

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Excoriation (skin picking) disorder in Israeli University students: prevalence and associated mental health correlates☆ Vera Leibovici, M.D. a,⁎, Sari Murad, M.D. a, Rena Cooper-Kazaz, M.D. b, Tamar Tetro, M.D. a, Nancy J Keuthen, Ph.D. c, Noa Hadayer, M.D. a, Tali Czarnowicki, M.D. a, Brian L. Odlaug, M.P.H. d a

Department of Dermatology Hadassah Hebrew University Medical Center, Jerusalem, Israel Clalit Health Services of Talbia Psychiatric Clinic, Jerusalem, Israel Department of Psychiatry, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA d Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark b c

a r t i c l e

i n f o

Article history: Received 14 April 2014 Revised 19 July 2014 Accepted 22 July 2014 Available online xxxx Keywords: Skin picking disorder Prevalence University students Comorbidity Health correlates

a b s t r a c t Objective: The purpose of the study was to examine the prevalence of excoriation (skin picking) disorder (SPD) and associated physical and mental health correlates in a sample of Israeli university students. Methods: Five thousand Israeli students were given questionnaires screening for SPD, depression, obsessive– compulsive disorder, body dysmorphic disorder and disruptive, impulse control and conduct disorders. A total of 2176 participants (43.6%) responded and were included in the analysis. Mean age was 25.1±4.8 (range 17–60) years, and 64.3% were female. Results: The proportion of students who were screened positive for SPD was 3.03%, with a nearly equal gender distribution (3.0% in females and 3.1% in males). There was a trend toward significantly higher rates of psychiatric problems such as generalized anxiety, compulsive sexual behavior and eating disorders in these students. Within the group of students screening positive for SPD, alcohol intake was higher in male students, while female students perceived themselves as less attractive. No association was found between depression and SPD. A high prevalence rate of skin picking was found within first-degree family members of the participants screening positive for SPD. Conclusions: Clinicians and public health officials within university settings should screen for SPD as it is common and associated with psychosocial dysfunction. © 2014 Elsevier Inc. All rights reserved.

1. Introduction Excoriation (skin picking) disorder (SPD), also referred to as pathological skin picking, dermatillomania or neurotic excoriation, has been recently introduced to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as an obsessive– compulsive related disorder. DSM-5 defines SPD as recurrent skin picking resulting in skin lesions. The individual must have made an attempt to decrease or stop the skin picking and the skin picking must cause clinically significant distress or impairment in important areas

☆ Disclosures: Dr. Vera Leibovici, Dr. Sari Murad, Dr. Rena Kazaz-Cooper, Dr. Tamar Tetro, Dr. Noa Hadayer and Dr. Tali Czarnowicki have nothing to disclose. Dr. Nancy Keuthen has received funding from the Trichotillomania Learning Center and is on the scientific advisory boards of the Trichotillomania Learning Center and the International Obsessive Compulsive Disorders Foundation. She is a stock shareholder of Pfizer Inc., Merck & Co. Inc., and Johnson & Johnson, and receives royalties from New Harbinger. Brian Odlaug has received a research grant from the Trichotillomania Learning Center, is a consult for Lundbeck Pharmaceuticals, and has received honoraria and royalties from Oxford University Press. ⁎ Corresponding author. E-mail address: [email protected] (V. Leibovici).

of functioning. The behavior cannot be attributed to substance intake or any other mental disorders. In adult populations, the prevalence of SPD ranges between 1.25% and 5.4% [1]. SPD among university students has been studied by various researchers throughout the world. In 2012, Odlaug et al. [2] surveyed 1916 American university students and found a prevalence of 4.2%. In the same year, Siddiqui et al. [3] reported a prevalence rate of SPD as high as 9% among 210 Pakistani students, while Calikusu et al. [4] discovered only 2.0% of 245 Turkish students to have SPD. In 2002, Bohne et al. [5] studied 133 German students and reported a prevalence of 4.6%, and finally, in 2000, Keuthen et al. [6] studied 105 American college students and reported that 3.8% presented with SPD. No studies to date, however, have examined the prevalence of SPD in an Israeli population which may differ culturally and ethnically from those in previous studies. Several studies have noted that psychosocial dysfunction is often present with SPD. In their study of American university students, for example, Odlaug et al. [2] found an association between SPD and affective disorders, anxiety, eating disorders, substance use and impulse control disorders. Male students with SPD had a higher body mass index (BMI) and perceived themselves as less attractive, while female students were more depressed. Tucker et al. [7] and

http://dx.doi.org/10.1016/j.genhosppsych.2014.07.008 0163-8343/© 2014 Elsevier Inc. All rights reserved.

Please cite this article as: Leibovici V., et al, Excoriation (skin picking) disorder in Israeli University students: prevalence and associated mental health correlates, Gen Hosp Psychiatry (2014), http://dx.doi.org/10.1016/j.genhosppsych.2014.07.008

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V. Leibovici et al. / General Hospital Psychiatry xxx (2014) xxx–xxx

Stein et al. [8] illustrated the great impact anxiety has on SPD in the general population. Anxiety causing distress can precipitate skin picking, and patients often report finding relief from this anxiety by picking their skin. The same authors also reported that individuals with SPD can have extensive problems in their family and social lives as well as at work. Individuals with SPD tended to avoid going out in public and were absent from work or school on a daily or weekly basis. One third of individuals reported difficulties studying [7]. The aim of our study was to evaluate the prevalence of SPD in Israeli university students and its association with sociodemographic variables, health correlates and psychiatric comorbidities. We hypothesized that SPD would be more common in females and students with SPD would have more psychosocial dysfunction when compared to students not screening positive for SPD.

During the period 2012–2013, questionnaires were distributed by the authors of the study to 5000 university students from the various faculties of the Hebrew University, Jerusalem, Israel, including medicine, pharmacy, nursing, law and sciences. The study protocol and consent process were approved by the Hadassah Medical Center's ethics committee for clinical trials. The survey was anonymous and students voluntarily consented to the survey by reading the introductory page and partaking in the study. Students were given a coffee shop gift card for participation in the study.

depressive symptoms [12]. Body dysmorphic disorder symptoms were assessed used the questionnaire described by Koran et al. [13]. The first two questions deal with the preoccupation of the participant with perceived defects in physical appearance not observable to others. Another two questions examine clinical distress or impairment in work, school or other areas of functioning, such as social interaction. Preoccupation with weight or body fat, better explained by eating disorder, was also addressed. The Minnesota Impulsive Disorders Interview, in a self-report version [14], was used to assess buying disorder, kleptomania, trichotillomania, intermittent explosive disorder, pyromania, gambling disorder, compulsive sexual behavior and compulsive exercise. Participants were asked whether they drink alcoholic beverages; if so, they were queried on how many drinks they had per week. Twelve drinks or more per week in women and 15 drinks or more in men were considered positive for problematic alcohol use. Respondents were asked about their use of recreational or illicit substances. Participants were asked about previous diagnosis of psychiatric conditions and about past or current dermatological diseases. If acne was endorsed, participants were asked to identify the body site(s) of pimples that they manipulate (face, chest or back, or other parts of the body). We also asked about first-degree family history of skin picking with the question: “Do you have a first-degree family member (e.g., parent, child or sibling) suffering from skin picking (as described in the introductory page)”; however, no direct interviews with family members were conducted. Hebrew versions of these questionnaires were used (either previous translations or translations by the authors of this study). Forward and back translations were conducted for all questionnaires before use.

2.2. Assessment

2.3. Statistical analysis

Sociodemographic data collected included age, gender and marital status. Measures of general health included BMI and perceived attractiveness by self and others. BMI was calculated based on selfreported height and weight. Perceived attractiveness by self and others was assessed with a single self-rated question (“On a scale of 1–10, how would you classify your attractiveness to yourself and others?”) as used by Odlaug and colleagues [2]. Response scores ranged from 1 to 10 (1 being least attractive and 10 being most attractive). SPD was assessed using the skin picking questionnaire from the Stanford University randomized telephonic study of the prevalence of compulsive buying, Internet addiction and pathologic skin picking. Methodology of this study is described by Koran and colleagues [9] in their paper on compulsive buying. Thirteen questions assessed SPD phenomenology requiring yes/no responses. Among these were items assessing the presence of noticeable skin damage, whether picking was attributable to an inflammation or itch from a medical condition, the presence of distress due to skin picking, whether there was missed work or school due to skin picking, or important events or social time was cancelled or avoided. The questionnaire also assessed sense of tension or nervousness building up before or while attempting to resist picking the skin and repeated attempts to resist or stop picking. Picking secondary to substance abuse or psychiatric issues were not directly queried. Parallel to the research criteria for SPD previously used by Keuthen et al. [10], participants were required to endorse lifetime picking resulting in skin damage with picking not attributable to an inflammation or itch from a medical condition. In addition, they had to endorse significant distress attributable to skin picking, missed work or school due to skin picking, or cancelled or avoided important events or social time due to skin picking. Non-SPD participants were those who did not meet the criteria for SPD. Obsessive–compulsive disorder (OCD) symptoms were assessed using the Obsessive Compulsive Inventory developed by Foa and colleagues [11]). The Beck Depression Inventory was used to assess

Students who did not complete the SPD questionnaire were excluded from the sample analysis. Mean values for independent samples were compared using t tests. Categorical variables were compared using a Fisher test for 2×2 tables. Chi-square statistics are also presented. All tests were two tailed and a p-value of less than .05 was considered significant.

2. Materials and methods 2.1. Survey description

3. Results Of the 5000 students who were given questionnaires, 2196 (43.9%) completed the survey. Due to incomplete responses to the questions pertaining to SPD, 20 subjects were additionally excluded, leaving a final sample of 2176 (43.5%) participants. Mean age of the participants was 25.1±4.8 (range 17–60) years. A total of 203 (9.3%) participants were above the age of 30. The proportion of the male participants was 64.3%, and 425 (19.5%) were married. A significantly higher prevalence of SPD was reported for the firstdegree family members of those participants screening positive vs. those screening negative for SPD (pb.001) (Table 3). 3.1. SPD vs. non-SPD between group comparisons The overall prevalence of students screening positive for SPD was 3.03% (n=66); 3.0% (n=42) in females and 3.1% (n= 24) in males. No statistically significant differences were noted between students screening positive or negative for SPD in terms of age (p=.55), gender (p= .89) or marital status (p= .63) (Table 1). BMI (p=.65) and attractiveness to others (p= .79) were not significantly different between participants screening positive and negative for SPD; however, females screening positive for SPD perceived themselves as being less attractive (p= .04) (Table 2). The prevalence of self-reported psychiatric and dermatologic disorders was similar between groups. A trend toward significance was found in the rate of compulsive sexual behavior between

Please cite this article as: Leibovici V., et al, Excoriation (skin picking) disorder in Israeli University students: prevalence and associated mental health correlates, Gen Hosp Psychiatry (2014), http://dx.doi.org/10.1016/j.genhosppsych.2014.07.008

V. Leibovici et al. / General Hospital Psychiatry xxx (2014) xxx–xxx Table 1 Demographics of university students screening positive or negative for SPD Variable

SPD (n=66)

Age, mean (±SD) 24.74 (4.95) [18–47] [range] Gender, 24 (36.36) n (%male) Marital status, 55 (83.33) n (%) Single Married 11 (16.67)

No-SPD (n=2110) 25.10 (4.79) [17–60] 752 (35.64)

Statistics

Table 3 Clinical correlates of students screening positive and negative for SPD p-Value

χ2=0.01

.89

χ2=0.35

.63

1688 (80)

422 (20)

groups with higher rates in students screening positive for SPD (p= .057) (Table 3). Generalized anxiety trended toward significance, again with higher rates in students with SPD (p=.092). Eating disorders also trended to significance in students with SPD (p=.07) (Table 3). Surprisingly, no significant differences were noted between groups in the self-reported rates of OCD and OCD-related disorders, such as trichotillomania (p= 1) and body dysmorphic disorder (p= 1) (Table 3). Concerning dermatological diseases, three diseases were selfreported by the students: acne, eczema and psoriasis. We found no significant differences in the occurrence of these three dermatological conditions between the two groups (p= .3, p= .68 and p= .59, respectively) (Table 3). 3.2. Within-group SPD analyses When comparing psychiatric disorders among participants screening positive for SPD, we found a significantly higher alcohol intake among male vs. female students (pb.001).There were no other significant differences in psychiatric comorbidity between male and female students in terms of depression, eating disorder, substance intake, OCD and OCD-related disorders (trichotillomania and body dysmorphic disorder), addictive disorders (gambling), disruptive, impulsive–control and conduct disorders (intermittent explosive disorder, pyromania and kleptomania) (Table 4). 4. Discussion Our study revealed a 3.03% prevalence of Israeli university students screening positively for SPD. This is within the range of other university student samples (2.0%–9%) [2–6] and similar to that of the general population (1.3%–5.4%) [1]. Although there was a wide age range for participants (18-–60 years), the mean age was approximately 25 and only 9.3% were over the age of 30. Thus, the majority of our sample was composed of young adults. We also found similar prevalence rates of males and females screening positively for SPD. This finding is in agreement with that of Tucker et al. [7] but in contrast to that found by Odlaug and colleagues Table 2 Health indices grouped by SPD

BMI (kg/m2) Male Female Perceived attractiveness Attractiveness of self Male Female Attractiveness to others Male Female

SPD (n=66)

No-SPD (n=2110)

Statistics

p-Value

23.00±1.49 20.60±7.03

23.17±4.95 21.80±4.68

t=0.45 t=1.03

.65 .30

7.50±1.69 6.83±1.64

7.37±1.62 7.35±1.60

t=0.39 t=2.04

.69 .04

7.67±1.78 7.76±1.65

7.75±1.57 7.88±1.61

t=0.26 t=0.48

.79 .62

All values are mean±SD. t=two-sample t-test. In the p-value, bold font is for statistical significant value.

Self-reported diagnosis

t=0.58 .55

t=two-sample t test. χ2=Pearson's chi-square.

Variable

3

SPD No-SPD Statistics (n=66) (n=2110)

Depression 1.52% 1.99% Generalized anxiety 3.03% 0.71% Eating disorder 3.03% 0.62% OCD 19.05% 23.54% Obsessive–compulsive-related disorders Body dysmorphic disorder 0% 0.63% Trichotillomania 0% 0.76% Substance-related and addictive disorders Alcohol intake 25.76% 20.76% Substance use 4.69% 2.87% Gambling 0% 0.19% Excessive shopping 3.03% 0.81% Compulsive sexual behavior 3.03 0.52% Disruptive, impulse–control and conduct disorder Intermittent explosive disorder 1.52% 0.81% Pyromania 0% 0.05% Kleptomania 1.52% 0.10% Dermatological disorders Acne 18.18% 9.81% Eczema 3.03% 2.56% Psoriasis 1.52% 1.33% Family members with SPD 22.95% 6.23%

p-Values

χ2=0.07 χ2=4.44 χ2=5.45 χ2=0.46

1 .09 .07 .58

χ2=0.37 χ2=0.50

1 1

χ2=0.96 χ2=0.71 χ2=0.12 χ2=3.65 χ2=6.75

.43 1

χ2=0.39 χ2=0.00 χ2=6.57

.42 1 .11

χ2=4.95 χ2=0.05 χ2=0.01 χ2=26.51

.3 .68 .59 2.85×10−5

.11 .05

χ2=Pearson's chi-square. In the p-value, bold font is for statistical significant value.

[2] (who found a higher prevalence in female students) and Calikusu et al. [4] (who reported a higher prevalence in male students). While SPD may be more common in females, these conflicting results illustrate that SPD may not be as female dominant as previously thought. Since females tend to present for treatment more often than men for these disorders, an anonymous survey such as this may illuminate a fairly substantial unmet male population in need of treatment. Our students, screening positive for SPD, presented with a higher (but not statistically significant) level of anxiety, which is known to worsen SPD [7,8]. Interestingly in our study, depression was not more prevalent among participants screening positive for SPD, as was found by Odlaug et al. [2]). This might be explained by the fact that most of our participants were young adults, and the risk of major depression increases after the age of 29 [15]. We also found an increased alcohol Table 4 Clinical correlates of students screening positive for SPD grouped by gender Self-reported diagnosis

Women (n=42)

Men (n=24)

Depression 7.14% 4.17% Generalized anxiety 78.57% 70.83% Eating disorder 2.38% 4.17% OCD 14.29% 28.57% Obsessive–compulsive-related disorders Body dysmorphic disorder “0” “0” Trichotillomania “0” “0” Substance-related and addictive disorders Alcohol intake 14.29% 45.83% Substance use 4.88% 4.35% Gambling “0” “0” Excessive shopping 4.76% “0” Compulsive sexual behavior 4.76% “0” Disruptive, impulse–control and conduct disorder Intermittent explosive disorder “0” 4.27% Pyromania “0” “0” Kleptomania 2.38% 0% Dermatological diseases Acne 23.81% 8.33% Eczema 2.38% 4.17% Psoriasis 2.38% “0” Family members with SPD 23.08% 22.73%

Statistics

p-Values

χ2=0.23 χ2=0.49 χ2=0.16 χ2=1.23

1 .55 1 .40

χ2 indeterminate χ2indeterminate

1 1

χ2=7.94 χ2=0.00 χ2 indeterminate χ2=1.17 χ2=1.17

.01 1 1 .53 .53

χ2=1.77 χ2indeterminate χ2=0.58

.36 1 1

χ2=2.45 χ2=0.16 χ2=0.58 χ2=0.00

.18 1 1 1

χ2=Pearson's chi-square. In the p-value, bold font is for statistical significant value.

Please cite this article as: Leibovici V., et al, Excoriation (skin picking) disorder in Israeli University students: prevalence and associated mental health correlates, Gen Hosp Psychiatry (2014), http://dx.doi.org/10.1016/j.genhosppsych.2014.07.008

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V. Leibovici et al. / General Hospital Psychiatry xxx (2014) xxx–xxx

intake among males screening positively for SPD compared to females. This is consistent with the findings of both Grant et al. [16] and Lochner et al. [17], who related SPD to addictive behaviors. An association between SPD and body dysmorphic disorder [18,19] and that between SPD and trichotillomania [20], as well as SPD and OCD [21,22], have been reported by several authors. To our surprise, none of our Israeli students screening positively for SPD endorsed either of these two OCD-related disorders, or OCD. This may be explained by the fact that our participants were not formally assessed by a psychiatrist. The fact that the first-degree family members of the participants screening positive for SP behavior were more affected by SPD than those of the students screening negative for SP behavior supports the proposed genetic etiology of SPD. In a study of 60 SPD patients conducted by Odlaug and Grant [1], 28.3% of subjects reported having a first-degree family member with SPD. Further, Neziroglu et al. [23] studied 40 SPD patients and found that 43% had a first-degree relative with SPD. Monzani et al.'s [24] twin study found that genetic factors accounted for 40% of skin picking by non-shared environmental factors of British twins. Our findings document the need for elevated awareness among Israeli and world health care providers, as well as university administrators, to the fact that SPD is a relatively common disorder among university students. Furthermore, it is associated with mental distress (higher alcohol consumption, potentially higher levels of anxiety, sexual compulsive behaviors, diminished self-perception of attractiveness) that should be addressed. 5. Limitations The major limitation was that the survey consisted only of selfreport measures and rating scales. The study could have benefited from a full psychiatric assessment of all participants diagnosed with SPD, though the anonymity of participants did not allow this. This might explain why no Israeli students endorsing criteria consistent for SPD presented with trichotillomania, body dysmorphic disorder or OCD. Furthermore, lack of formal psychiatric assessments also made us unable to make a differential diagnosis between skin picking and other psychiatric disorders, such as body dysmorphic disorder. Another limitation involves the use of translated and retranslated questionnaires for assessment. The authors of this study intend to validate these questionnaires in Hebrew in the near future. Acknowledgments The authors would like to thank Dr. Lorrin M. Koran for generously sharing questionnaires and for providing helpful suggestions in the planning of the study.

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Please cite this article as: Leibovici V., et al, Excoriation (skin picking) disorder in Israeli University students: prevalence and associated mental health correlates, Gen Hosp Psychiatry (2014), http://dx.doi.org/10.1016/j.genhosppsych.2014.07.008