Schizophrenia, Substance Abuse, and Violent Crime

Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, England.
JAMA The Journal of the American Medical Association (Impact Factor: 35.29). 06/2009; 301(19):2016-23. DOI: 10.1001/jama.2009.675
Source: PubMed


Persons with schizophrenia are thought to be at increased risk of committing violent crime 4 to 6 times the level of general population individuals without this disorder. However, risk estimates vary substantially across studies, and considerable uncertainty exists as to what mediates this elevated risk. Despite this uncertainty, current guidelines recommend that violence risk assessment should be conducted for all patients with schizophrenia.
To determine the risk of violent crime among patients diagnosed as having schizophrenia and the role of substance abuse in mediating this risk.
Longitudinal designs were used to link data from nationwide Swedish registers of hospital admissions and criminal convictions in 1973-2006. Risk of violent crime in patients after diagnosis of schizophrenia (n = 8003) was compared with that among general population controls (n = 80 025). Potential confounders (age, sex, income, and marital and immigrant status) and mediators (substance abuse comorbidity) were measured at baseline. To study familial confounding, we also investigated risk of violence among unaffected siblings (n = 8123) of patients with schizophrenia. Information on treatment was not available.
Violent crime (any criminal conviction for homicide, assault, robbery, arson, any sexual offense, illegal threats, or intimidation).
In patients with schizophrenia, 1054 (13.2%) had at least 1 violent offense compared with 4276 (5.3%) of general population controls (adjusted odds ratio [OR], 2.0; 95% confidence interval [CI], 1.8-2.2). The risk was mostly confined to patients with substance abuse comorbidity (of whom 27.6% committed an offense), yielding an increased risk of violent crime among such patients (adjusted OR, 4.4; 95% CI, 3.9-5.0), whereas the risk increase was small in schizophrenia patients without substance abuse comorbidity (8.5% of whom had at least 1 violent offense; adjusted OR, 1.2; 95% CI, 1.1-1.4; P<.001 for interaction). The risk increase among those with substance abuse comorbidity was significantly less pronounced when unaffected siblings were used as controls (28.3% of those with schizophrenia had a violent offense compared with 17.9% of their unaffected siblings; adjusted OR, 1.8; 95% CI, 1.4-2.4; P<.001 for interaction), suggesting significant familial (genetic or early environmental) confounding of the association between schizophrenia and violence.
Schizophrenia was associated with an increased risk of violent crime in this longitudinal study. This association was attenuated by adjustment for substance abuse, suggesting a mediating effect. The role of risk assessment, management, and treatment in individuals with comorbidity needs further examination.

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    • "Aggressive, hostile behavior is well recognized in patients with schizophrenia (Buckley et al., 2011;Volavka et al., 2011;Citrome and Volavka, 2014;Volavka et al., 2014;Citrome and Volavka, 2015). Studies have shown a higher incidence of violent, aggressive behavior among patients with schizophrenia compared with the general population , and the incidence increases further with comorbid substance abuse (Eronen et al., 1996;Wallace et al., 1998;Fazel et al., 2009). Hostile and aggressive behavior may occur from an acute episode of schizophrenia that is precipitated by noncompliance with psychotropic medication or a failure of the current medication regimen (Ascher-Svanum et al., 2006;Citrome and Volavka, 2011). "
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    ABSTRACT: This study aimed to evaluate the effects of aripiprazole lauroxil on hostility and aggressive behavior in patients with schizophrenia. Patients aged 18-70 years with a diagnosis of schizophrenia and currently experiencing an acute exacerbation or relapse were randomized to intramuscular (IM) aripiprazole lauroxil 441 mg (n=207), 882 mg (n=208), or placebo (n=207) for 12 weeks. In post-hoc analyses, hostility and aggression were assessed by the Positive and Negative Syndrome Scale (PANSS) Hostility item (P7) and a specific antihostility effect was assessed by adjusting for positive symptoms of schizophrenia, somnolence, and akathisia. The PANSS excited component score [P4 (Excitement), P7 (Hostility), G4 (Tension), G8 (Uncooperativeness), and G14 (Poor impulse control)], and the Personal and Social Performance scale disturbing and aggressive behavior domain were also assessed. Of the 147 patients who received aripiprazole lauroxil 882 mg and with a baseline PANSS Hostility item P7 more than 1, there was a significant (P<0.05) improvement versus placebo on the PANSS Hostility item P7 score by mixed-model repeated-measures at the end of the study, which remained significant when PANSS-positive symptoms and somnolence or akathisia were included as additional covariates. The proportion with PANSS Hostility item P7 more than 1 at endpoint was significantly (P<0.05) lower with aripiprazole lauroxil versus placebo (53.6, 46.1, and 66.3% for 441, 882 mg, and placebo). A significant (P<0.05) improvement was found with aripiprazole lauroxil versus placebo for change from baseline in the PANSS excited component score. The proportion of patients with aggressive behavior on the Personal and Social Performance scale was significantly (P<0.05) lower for aripiprazole lauroxil: 30.0% for 441 mg versus 44.1% for placebo (P=0.006) and 22.2% for 881 mg (P<0.001 versus placebo). Treatment with aripiprazole lauroxil resulted in decreases in agitation and hostility in patients with schizophrenia and this antihostility effect appears to be independent of a general antipsychotic effect.
    No preview · Article · Oct 2015 · International clinical psychopharmacology
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    • "Indeed, the strongest predictors of violent recidivism for mentally ill offenders are the same as those for non-mentally ill violent offenders, and the presence of a criminal history (including one that antedates the onset of psychosis) is a stronger predictor of violence than psychotic symptoms (Bonta, Law, & Hanson, 1998). However, even when these factors are taken into account, the rate of schizophrenia-associated violence is higher than in the general population (Fazel et al., 2009a, 2009b; Hodgins et al., 2007a; Steadman et al., 1998; Swanson et al., 1990; Volavka, 2013; see above). Much of this increased risk may be due to antisocial personality features and related traits (e.g., impulsivity), as discussed above. "
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    ABSTRACT: Published findings on the relationship between schizophrenia and violence have been mixed, due to differences in study design and quality. In this review, we address the issue with an emphasis on characterizing who is most likely to be violent and when. We conclude that: (1) individuals with schizophrenia are at an increased risk for violence due to specific psychotic symptoms; (2) this risk is increased by brain abnormalities, psychiatric comorbidities, and demographic factors that are not specific to schizophrenia; (3) the majority of violent offenses committed by people with schizophrenia are indistinguishable from offenses committed by others; and (4) despite our knowledge of factors related to increased violence risk and the existence of effective treatments to mitigate this risk, valid risk assessment instruments for this population are lacking, and treatment strategies are rarely employed at any level of psychiatric care. In short, while most people with schizophrenia are not violent and violence committed by people with this condition accounts for only a small percentage of overall violent crime, there is nevertheless a significantly increased risk for violence among subgroups in this population. This has implications for people living with people with schizophrenia, mental health professionals, administrators of psychiatric care facilities, law enforcement personnel, the court system, and policymakers.
    Full-text · Article · May 2015
    • "That the misuse of substances is highly correlated with offending in general (Grann & Fazel, 2004) and when co-morbid with other mental disorders (Fazel et al. 2009b) can hardly be contested. However, whether mental illness poses an increased risk of offending over and above the presence of co-morbid misuse has been debated (Elbogen & Johnson, 2009; Van Dorn et al. 2012). "
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    No preview · Article · Apr 2015 · Psychological Medicine
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