شیوع قربانی شدن زورگویی در میان بیماران روان پریشی اپیزود اول و کنترلهای غیرعاطفی

Abstract Background Despite increasing evidence suggesting that childhood maltreatment is significantly associated with psychosis, the specific role of bullying in the onset of psychotic disorders is still unclear. This study aimed to examine whether bullying was more prevalent amongst individuals presenting to services for the first time with a psychotic disorder than in unaffected community controls. Methods Data on exposure to bullying, psychotic symptoms, cannabis use and history of conduct disorder were collected cross-sectionally from 222 first-presentation psychosis cases and 215 geographically-matched controls. Bullying victimisation was assessed retrospectively as part of the Brief Life Events schedule. Logistic regression was used to examine associations between exposure to bullying and case–control status, while controlling for potential confounders.

1. Introduction In attempting to better understand the aetiology of psychosis, a substantial body of research has focused on the role of psychosocial factors. A quantitative review and meta-analysis of the available empirical literature indicated that exposure to childhood adverse experiences is strongly associated with increased risk for psychosis (Varese et al., 2012). Indeed, large-scale general population studies indicate that exposure to maltreatment in childhood (such as sexual, physical and emotional abuse, and neglect) increases the risk of experiencing psychotic symptoms in adolescence as well as full-blown psychotic disorders in adulthood (Read et al., 2005, Morgan and Fisher, 2007 and Schafer and Fisher, 2011). However, the specific role of bullying in the later development of psychotic disorder is still unclear (Van Dam et al., 2012). A recent survey conducted in the UK reported that approximately 25% of children had been bullied by peers during their school years (Radford et al., in press), suggesting that bullying is a common form of early victimisation. Being a victim of bullying has been associated with a wide range of mental health problems in adolescence (Arseneault et al., 2010) as well as sub-clinical psychotic symptoms (Lataster et al., 2006, Campbell and Morrison, 2007, Kelleher et al., 2008, Nishida et al., 2008, Schreier et al., 2009, Arseneault et al., 2011, Mackie et al., 2011, Fisher et al., 2012, Kelleher et al., 2013 and Mackie et al., 2013). One general population study has also reported that there is a higher prevalence of bullying victimisation in adults considered to meet criteria for probable psychosis when compared to those without such symptoms (Bebbington et al., 2004). A study of adolescent psychiatric inpatients found that victims of bullying had psychotic disorders two to three times more often than the bullies or bully-victims, but the association was not significant (Luukkonen et al., 2010). Sourander et al. (2007) studied predictive associations between bullying victimisation at age 8 years and psychiatric disorders in early adulthood. They also found no significant association between being a pure victim of bullying and psychotic disorder in adulthood. Therefore, further investigation of the association between bullying victimisation and psychotic disorder is warranted. None of the studies to date has explored the association between bullying victimisation and first clinical presentation for psychotic disorders in comparison to a control group. Neither have potential modifiers been investigated. For instance, gender (Fisher et al., 2009) and cannabis use (Houston et al., 2011 and Mackie et al., 2013) have been shown to modify associations between other forms of childhood adversity and psychosis, and children who have been bullied are also at risk of engaging in anti-social behaviours (Liang et al., 2007). Additionally, given the strong associations found between bullying victimisation and depression (Hawker and Boulton, 2000), it also seems important to explore whether similar associations will hold for both schizophrenia-spectrum and affective psychosis diagnoses. Therefore, the aim of our study was to extend the literature on the association between bullying victimisation and psychosis by focusing on clinically-relevant psychotic disorders and exploring a range of possible modifiers. First, we examined whether a history of bullying victimisation was more prevalent amongst individuals presenting to mental health services for the first time with a psychotic disorder than unaffected community controls. Second, we explored the association between bullying and psychosis by gender, conduct disorder, diagnosis and cannabis use.

3. Results 3.1. Sample characteristics A total of 222 people with psychosis and 215 controls provided information on exposure to bullying. There were no significant differences between psychosis cases and controls with versus without bullying data in terms of demographic characteristics (results, not shown, are available from the authors). The psychosis cases comprised 129 (58.11%) diagnosed with schizophrenia-spectrum disorders and 45 (20.27%) with affective psychosis. Sociodemographic data by case and control status is presented in Table 1. There was no significant difference between psychosis cases and unaffected controls in terms of age and gender, but controls were more likely to have at least GCSE-level qualifications than cases and be from a White British or White Other ethnic background. Sociodemographic characteristics were therefore controlled for in the subsequent analysis.