Psychiatry Research 281 (2019) 112518 Contents lists available at ScienceDirect Psychiatry Research journal homepage: www.elsevier.com/locate/psychres Obsessive–compulsive or addiction? Categorical diagnostic analysis of excoriation disorder compared to obsessive-compulsive disorder and T gambling disorder ⁎ Elen Cristina Batista Oliveirraa, , Chelsea L. Fitzpatrickb, Hyoun S. Kimb, Daniel Carr Ribeiro Gulassaa, Roberta Souza Amarala, Nicoli de Mattos Cristianaa, Ana Yaemi Hayashiuchia, Daniel S. McGrathb, Hermano Tavaresa a Programa Ambulatorial de Transtornos do Impulso (PRO-AMITI), Instituto de Psiquiatria (IPq), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Rua Artur de Azevedo, 145, Cerqueira Cesar, CEP: 05404-010, Sao Paulo, SP, Brazil b Department of Psychology, University of Calgary, Calgary, Alberta, Canada ARTICLE INFO ABSTRACT Keywords: Excoriation disorder (ED) is currently classified in the 5th edition of the Diagnostic and Statistical Manual of Excoriation disorder Mental Disorders’ Obsessive–compulsive and Related Disorders section (OCRD). However, there remain debates Skin picking disorder regarding whether ED is related to obsessive–compulsive disorder (OCD) or whether it is better conceptualized – Obsessive compulsive as a behavioral addiction. The present research compared the diagnostic overlap and psychiatric comorbidities Impulse control disorders of 121 individuals seeking treatment for ED (n = 40), OCD (n = 41) and gambling disorder (GD) (n = 40). ED Gambling disorder was more likely to overlap with OCD (n = 14) than GD (n = 3). Compared to OCD, ED had similar frequencies of Comorbidity – DSM-5 other body focused repetitive behaviors (BFRBs), but higher frequency of addictive behaviors (Odds Ratio OR = 11.82). In comparison to GD, ED had similar frequencies of addictive behaviors, but higher frequency of BFRBs (OR=19.67). The results support the recent classification of ED as an OCRD. However, ED presents an association with behavioral addictions that suggests a mixed impulsive-compulsive nature. A limitation of the present research was the use of a non-validated semi-structured clinical interview to diagnose impulse control disorders. Future research should examine other characteristics (e.g., epidemiology, neurobiology, genetics, treatment response) to further investigate whether ED should remain classified as an OCRD. 1. Introduction et al., 2006; Wilhelm et al., 1999). There is considerable variation in the prevalence of ED which Excoriation disorder (ED) was first reported in 1875 by British ranges from 1.4% to 5.4% (Stein et al., 2010; Keuthen et al., 2010; Teng dermatologist Erasmus Wilson (1875), who named it “Neurotic Ex- et al., 2002). Furthermore, females account for 60–80% of ED cases, coriation.” Presently, ED's nomenclatures include “skin picking”, “skin with onset occurring in adolescence. Specifically, the onset of ED tends picking disorder”, “pathological skin picking” and “self-inflicted skin to be 12.4 years old in clinical samples (Siddiqui et al., 2012; Calikusu picking” (Grant and Stein, 2014; Odlaug and Grant, 2010). The term et al., 2012; Leibovici et al., 2014; Keuthen et al., 2000) and 15 years excoriation disorder was first proposed in the fifth edition of Diagnostic old in the general community (Wilhelm et al., 1999; Teng et al., 2002). and Statistical Manual of Mental Disorders (DSM-5) (American Psy- ED frequently co-occurs with other psychiatric disorders, including chiatric Association, 2013) and is now the most commonly used term. elevated rates of suicidality (Odlaug and Grant, 2010; Wilhelm et al., ED is characterized by repetitive and excessive behaviors such as 1999). For example, Odlaug and Grant (2010) found that 15% of ED scratching, squeezing, and picking on healthy skin, which may result in patients had experienced involuntary psychiatric hospitalization and significant lesions, skin damage and psychological distress 11.5% had previously attempted suicide. Furthermore, in a clinical (Snorrason et al., 2012). Individuals with ED often exhibit an un- sample of 33 ED patients, the most common comorbid disorder was controllable urge to scar the skin and failure to control these repetitive obsessive–compulsive disorder (OCD, 52%), followed by alcohol abuse/ behaviors (Grant and Odlaug, 2009; Stein et al., 2010; Chamberlain addiction (39%) and body dimorphic disorder (BDD, 32%) ⁎ Corresponding author. E-mail address: [email protected] (E.C.B. Oliveirra). https://doi.org/10.1016/j.psychres.2019.112518 Received 29 December 2018; Received in revised form 4 August 2019; Accepted 10 August 2019 Available online 05 September 2019 0165-1781/ © 2019 Published by Elsevier B.V. E.C.B. Oliveirra, et al. Psychiatry Research 281 (2019) 112518 (Wilhelm et al., 1999). These patterns of comorbidity were also found the behavior and elevated levels of impulsivity (Odlaug and Grant, in a sample of University students (Leibovici et al., 2014). Comorbid 2010; Oliveira et al., 2015). Lastly, ED and addictions appear to show anxiety and mood disorders are also frequent in ED, specifically, social similar treatment response, including both psychological (such as 12- phobia, generalized anxiety disorder, and major depressive disorder step programs) and pharmacological treatments, such as naltrexone and (Machado et al., 2018). topiramate (Grant et al., 2010). Yet, to our knowledge, no study to date has directly compared ED to 1.1. Obsessive–compulsive or addiction? The classification issue of OCRDs. The goal of the present study was to address this empirical gap excoriation disorder by comparing ED with two clinical paradigms of OCRD and BAs, OCD and GD, respectively, to assess whether ED is more related to OCRDs or ED as a psychiatric diagnosis was first mentioned in DSM-IV as “skin BAs. To this end, we assessed the diagnostic overlap and patterns of picking” and placed within the Impulse Control Disorders (ICDs) not comorbidity in ED, OCD, and GD. Patterns of comorbidity may provide otherwise classified section, however, without any specific diagnostic more insight into the classification of ED as psychiatric disorders that criteria (APA, 1994). The ICD section also included disorders such as share related phenomenological features and are more likely to co- intermittent explosive disorder, kleptomania, pyromania, pathological occur (Abramowitz and Jacoby, 2015). Indeed, if ED is an OCRD, it gambling, and trichotillomania. In a revised version of the fourth edi- should overlap with OCD to a greater extent than with GD, including in tion of the DSM (DSM-IV-TR), ICDs were defined as disorders char- psychiatric comorbidities. Additionally, both ED and OCD should have acterized the failures to resist impulses, which may result in personal or a greater association with other BFRBs compared to people with GD. interpersonal harms (APA, 2000). In other words, individuals experi- Conversely, if ED shares underlying similarities to BAs, then it would be ence tension or increasing arousal before committing the impulsive act, expected to overlap with GD, as well as with other addictive disorders followed by pleasure, gratification, or relief from the urge when en- and share similar psychiatric comorbidity profiles with addictions. The gaging in ICDs. present research directly tested this empirical assertion. The fifth and latest edition the DSM-5 (APA, 2013), brought a ra- dical change of the ICD section. First, the section on ICDs was relabeled 2. Methodology as Disruptive, Impulse-Control and Conduct Disorders. Skin picking disorder was renamed to ED and gained specific diagnostic criteria. 2.1. Participants Importantly for the present research, ED (along with trichotillomania) was moved to the obsessive–compulsive related disorders (OCRD) Participants were recruited from the Instituto de Psiquiatria, under the subgroup of body-focused repetitive behaviors (BFRB). Sec- Hospital das Clinicas, Faculdade de Medicina, Universidade de Sao ondly, pathological gambling was renamed to gambling disorder (GD) Paulo (HCFMUSP) from 2014 to 2017. Eligible patients (i.e., meeting and moved to the Substance-related and Addictive Disorders section, diagnostic criteria for one of three target disorders according to the becoming the first behavioral addiction formally recognized. The re- DSM-5) seeking treatment were invited to participate. In our study, two maining disorders previously classified as ICDs remained in the new individuals were excluded because of illiteracy, one patient was acutely section with the addition of oppositional defiant disorder, conduct psychotic, two had comorbidities with dermatological lesions and one disorder and antisocial personality disorder. These changes were made patient's primary concern was not ED despite their self-inflicted skin with the goal of providing a more precise and narrow scope of im- legions in the ED sample. For the GD sample: 78 individuals dropped pulsive disorders, characterized by behaviors that violate the rights of out, one did not sign the informed consent, one was acutely psychotic, others and conflict with societal norms (APA, 2013). one patient did not understand the research protocol due to language Despite the merit of building a less heterogeneous group of dis- barriers and one patient did not meet criteria for GD. Finally, 18 in- orders, the reconfiguration of the DSM-5 classification system was not dividuals in the OCD sample did not finish the protocol and one patient without controversy. While the reclassification of GD as an addiction