پرخاشگری کلامی در مقابل پرخاشگری فیزیکی در اختلال انفجاری متناوب

Intermittent Explosive Disorder (IED) is the only adult psychiatric diagnosis for which pathological aggression is primary. DSM-IV criteria focused on physical aggression, but Diagnostic and Statistical Manual of Mental Disorders (DSM-5) allows for an IED diagnosis in the presence of frequent verbal aggression with or without concurrent physical aggression. It remains unclear how individuals with verbal aggression differ from those with physical aggression with respect to cognitive–affective deficits and psychosocial functioning. The current study compared individuals who met IED criteria with either frequent verbal aggression without physical aggression (IED-V), physical aggression without frequent verbal aggression (IED-P), or both frequent verbal aggression and physical aggression (IED-B) as well as a non-aggressive personality-disordered (PD) comparison group using behavioral and self-report measures of aggression, anger, impulsivity, and affective lability, and psychosocial impairment. Results indicate all IED groups showed increased anger/aggression, psychosocial impairment, and affective lability relative to the PD group. The IED-B group showed greater trait anger, anger dyscontrol, and aggression compared to the IED-V and IED-P groups. Overall, the IED-V and IED-P groups reported comparable deficits and impairment. These results support the inclusion of verbal aggression within the IED criteria and suggest a more severe profile for individuals who engage in both frequent verbal arguments and repeated physical aggression.

Although aggression is a recognized global health concern (Krug et al., 2002), and most aggression is affective in nature (Averill, 1983), there exists only one psychiatric diagnosis for which affective aggression is the core symptom: Intermittent Explosive Disorder (IED). According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), IED is defined as the failure to resist aggressive impulses that result in repeated acts of verbal and/or physical aggression ( American Psychiatric Association, 2013). The inclusion of verbal aggression represents a major change over previous iterations of IED in the DSM. IED is both common, with lifetime prevalence rates of 5.4–7.3% (Kessler et al., 2005, Kessler et al., 2006, Coccaro et al., 2005 and Ortega et al., 2008), and highly impairing. IED is associated with substantial distress, health problems, troubled relationships, occupational difficulty, and legal or financial problems (McElroy et al., 1998 and McCloskey et al., 2010). Individuals with IED are rated as lower in overall psychosocial functioning than healthy volunteers or psychiatric controls (McCloskey et al., 2006 and McCloskey et al., 2008a). In addition, IED has been associated with several cognitive–affective deficits, including poor impulse control and affect dysregulation. Individuals with IED report increased impulsivity on self-report measures, but do not appear more impulsive on validated laboratory tasks of impulsivity (Coccaro et al., 1998 and Best et al., 2002). An argument could be made that the heterogeneity of “impulsivity” across measures (Evenden, 1999 and Whiteside and Lynam, 2003) is likely to be responsible for this inconsistency. However, the relationship between IED and general impulsivity has been ephemeral even within the same measure (e.g., Barratt Impulsivity Scale (BIS)) (Coccaro et al., 1998 and Best et al., 2002). This suggests that IED may not be wholly characterized as a problem of impulse control and that the aggressive outbursts may be more related to other constructs, such as emotion regulation. Individuals with IED have difficulty regulating their behavior under periods of extreme stress or intense emotion, particularly anger (Davidson et al., 2000 and Siever, 2008). This difficulty regulating emotion does not appear to be limited to anger; IED is significantly associated with deficits in overall affect regulation relative to both healthy volunteers and other psychiatric populations (Coccaro et al., 1998, McCloskey et al., 2006 and McCloskey et al., 2008b). Despite marked cognitive–affective deficits and psychosocial impairment, empirical research on IED has been limited. This is partially due to a lack of congruence in defining the disorder. Prior to DSM-5, an IED diagnosis was limited to individuals who reported physical aggression. This may be related to the fact that physical aggression is often considered more severe than verbal aggression (e.g., Salari and Baldwin, 2002). However, studies showed that individuals with frequent verbal aggression (i.e., two or more times a week for a month or more) reported similar levels of anger, aggression, and impairment comparable to their IED counterparts, most of whom had high levels of both verbal and physical aggression (McCloskey et al., 2006, Coccaro, 2011 and Coccaro, 2012). These findings have, in part, led to the inclusion of verbal aggression in DSM-5 IED. However, there has been limited research comparing “pure” verbal and physical sub-types of IED. McCloskey et al. (2008a) found no differences between an IED group with both physical and verbal aggression and a verbally aggressive group on measures of trait aggression, trait anger, and clinical impairment, with both groups showing more aggression, anger, and impairment than a psychiatric control group. However, no study to date has directly compared individuals with pathological physical (but not verbal) aggression to those with pathological levels of verbal (but not physical) aggression. Understanding how these aggressive groups differ in terms of cognitive–affective functioning and psychosocial impairment will provide important insight into the homogeneity of the IED diagnosis (Coccaro and Kavoussi, 1997 and Coccaro et al., 1998). The current study examined areas of increased cognitive–affective deficits and psychosocial impairment in three distinct groups of individuals with IED: (1) individuals meeting for IED verbal aggression (i.e., verbal outbursts, such as heated arguments, yelling and cursing, occurring on average at least twice a week for 3 months or more; IED based on only verbal aggression (IED-V) group), (2) individuals meeting IED physical aggression criteria (i.e. either three assaults on people, animals, or property with damage/injury over a 12 month period or an average of two assaults on people, animals or property without injury/damage a week for 3 months; IED based on only physical aggression (IED-P) group), (3) individuals met both physical and verbal IED criteria; IED based on both verbal and physical aggression (IED-B) group. The three IED variants were compared to each other as well as to a psychiatric control group consisting of individuals diagnosed with a personality disorder, including personality disorder not otherwise specified, who did not meet any of the DSM-5 IED aggression criteria (personality-disordered (PD) group). All participants were assessed for the severity of deficits in anger, anger dyscontrol, and aggression using a multi-method approach that included behavioral, questionnaire, and clinical interview measures. Putative associated constructs of affective lability, impulsivity, and psychosocial functioning were also assessed. It was predicted that IED-V participants would report less physical aggression than the other IED groups, whereas IED-P participants would report less verbal aggression than the other IED groups. No other differences were expected among IED groups on measures of anger, anger dyscontrol, and aggression. Further, it was expected that all IED groups would show higher levels of anger, anger dyscontrol, and aggression relative to the PD control group. Lastly, it was predicted that all IED groups would show decreased psychosocial functioning and increased levels of affect lability and impulsivity compared to the PD control group, but not differ from each other on these constructs.

Analyses were conducted two-tailed at the 0.05 level of significance. For measures comprised of multiple scales, MANOVA analyses were first used to examine multivariate effects of diagnostic status and gender as well as gender⁎group interactions. Subsequent univariate analyses were performed to examine the main effect of diagnostic group, gender, and gender⁎group interactions. For significant group main effects resulting from ANOVA analyses, post-hoc mean comparisons were done using Tukey׳s HSD test (p<0.05). For significant interactions, simple effects analyses were performed. For significant χ2 analyses, single degree of freedom χ2 analyses were performed post-hoc to determine significant differences of proportions between groups. Effect sizes are provided using partial eta squared (ήp2) for analyses of variance. For ήp2, 0.01, 0.06 and 0.14 are considered small, medium and large effect sizes ( Cohen, 1988). It should be noted that 38 subjects either did not complete the TAP (n=27) or did not believe the deception (n=11). Thus, for analyses using the TAP, there are a total of 264 participants (34 IED-V, 57 IED-P, 96 IED-B, and 77 PD).