Co-Occurrence of Avoidant Personality Disorder and Child Sexual Abuse Predicts Poor Outcome in Long-Standing Eating Disorder KariAnne R. Vrabel, Asle Hoffart, and Øyvind Rø Modum Bad Psychiatric Center Egil W. Martinsen Aker University Hospital and University of Oslo Jan H. Rosenvinge University of Tromsø Few consistent predictive factors for eating disorder have been identified across studies. In the current 5-year prospective study, the objective was to examine whether (a) personality disorder and child sexual abuse predict the course of severity of eating disorder symptoms after inpatient treatment and (b) how the predictors interact. A total of 74 patients with long-standing eating disorder and mean age of 30 years were assessed at the beginning and end of inpatient therapy and at 1-, 2-, and 5-year follow-up. A mixed model was used to examine the predictors. Avoidant personality disorder and child sexual abuse interacted in predicting high levels of eating disorder over a long-term course. These results suggest that eating disorder, avoidant personality disorder, and sequelae after child sexual abuse are potential targets for treatment that need further investigation. Keywords: eating disorder, personality disorder, child sexual abuse, mediators, moderators Eating disorder (ED) ranks among the 10 leading causes of disability among young women (Mathers, Vos, Stevenson, & Begg, 2000) and anorexia nervosa (AN) has the highest mortality rate of all mental disorders (Millar et al., 2005; Zipfel, Lowe, Reas, Deter, & Herzog, 2000). Factors predicting treatment outcome and course in ED have been sought mainly in three specific areas: individual, environmental, and therapeutic. So far, few predictive factors have been replicated across studies. Several studies have evaluated the effects of personality disorder (PD) on the course and outcome of ED. Obsessive-compulsive PD traits have been found to be a poor prognostic feature among anorexic patients (Lilenfeld, Wonderlich, Riso, Crosby, & Mitchell, 2006; Stein- hausen, 2002), whereas histrionic PD indicated a favorable out- come (Steinhausen, 2002). Avoidant PD is one of the most prev- alent PDs in the ED literature (Rosenvinge, Martinussen, & Ostensen, 2000). The Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM–IV; American Psychiatric Association, 1994) reported that the prevalence of avoidant PD was between 0.5% and 1.0% in the general population. However, across ED diagnoses, this increases from 16% to 27%, making it one of the most common PD diagnoses in the ED population (Sansone, Levitt, & Sansone, 2005). Herzog’s longitudinal studies on treatment-seeking anorexics and bulimics found no evidence that PD predicts either longitudinal outcome (Herzog et al., 1999) or ED relapse (Keel, Dorer, Franko, Jackson, & Herzog, 2005). However, a reanalysis of the same sample revealed that avoidant- insecure scores showed consistent associations with poor function- ing and outcome, including failure to show ED improvement, poor global functioning after five years, and high treatment utilization after five years (Thompson-Brenner et al., 2008). Despite the high prevalence of avoidant PD, there is still limited understanding of the specific impact of avoidant PD in patients with ED on the medium- to long-term course of ED. In our study, we have used borderline, obsessive-compulsive, and avoidant PD as predictors in the analyses. Very few studies have examined whether having experienced child sexual abuse (CSA) could predict a poor outcome in ED, despite clinical experience indicating that this may be the case. One study found that a history of sexual abuse and exposure to other violent acts is related to poor early response to treatment of ED, as well as to greater dropout and relapse rates (Rodriguez, Perez, & Garcia, 2005). However, as Rodriguez et al. (2005) pointed out, there is a need to evaluate the long-term impact of such a history and whether CSA may predict treatment outcome in ED. There may be a high prevalence of CSA among individuals seeking inpatient treatment for AN (Carter, Bewell, Blackmore, & Woodside, 2006), and a history of CSA can be associated with more severe psychiatric disturbance overall and a higher rate of dropout for patients of the binge–purge subtype (Carter et al., 2006). In summary, there are reasons to hypothesize that CSA among ED patients may predict a poor treatment outcome and a nonfavorable course of treatment. The contribution of CSA and PD may affect ED outcome and course in several ways. First, CSA could moderate the effects of PD on the ED course (moderator model). For instance, avoidant KariAnne R. Vrabel, Asle Hoffart, and Øyvind Rø, Research Institute, Modum Bad Psychiatric Center, Vikersund, Norway; Egil W. Martinsen, Clinic for Mental Health, Aker University Hospital, Oslo, Norway, and Insti- tute of Psychiatry, University of Oslo, Oslo, Norway; Jan H. Rosenvinge, Department of Psychology, University of Tromsø, Tromsø, Norway. This research was supported by the Norwegian Women’s Public Health Association and the Legacy of Haldis and Josef Andresen. Correspondence concerning this article should be addressed to KariAnne R. Vrabel, Research Institute, Modum Bad Psychiatric Center, N-3370 Vikersund, Norway. E-mail: karianne.vrabel@modum-bad.no Journal of Abnormal Psychology © 2010 American Psychological Association 2010, Vol. 119, No. 3, 623– 629 0021-843X/10/$12.00 DOI: 10.1037/a0019857 623 This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.