Mental illness, substance use disorder, and violent offending Challenge of dual diagnosis: Current perspectives North West Forensic Academic Network Manchester, U.K., 24 November, Martin Grann Centre for Violence Prevention Karolinska Institute Stockholm, Sweden

Mental illness Substance use Violent crime ”Dual Diagnosis” A B Dual diagnosis: The relationship between substance use disorders, mental illness, and violent crime

MENTAL ILLNESS AND VIOLENCE Are the mentally disordered more dangerous than others? (Is the public fear of psychiatric patients warranted?)

Mental illnessViolence ? A violent act A violent act A mental illness A mental illness A causal link between illness and act of violece A causal link between illness and act of violece

Mental illnessViolence ? These assumptions are fundamental to... These assumptions are fundamental to... Mens rea, culpability, medico-legal insanity; differentiated sanctions (NGRI, NCRAMD, fitness to plead; ”fängelseförbud” etc) Mens rea, culpability, medico-legal insanity; differentiated sanctions (NGRI, NCRAMD, fitness to plead; ”fängelseförbud” etc) Indeterminate institutionalisations - dangerousness (Dangerous Offenders Act, preventative detention, DSPD, "Särskilda skyddsreaktioner” etc) Indeterminate institutionalisations - dangerousness (Dangerous Offenders Act, preventative detention, DSPD, "Särskilda skyddsreaktioner” etc)

SUPPORT FOR and AGAINST AN ALLGED ASSOCIATION BETWEEN MENTAL ILLNESS & VIOLENCE (1) From Plato to Hollywood… The mythology of the mad serial killer High-profile cases

SUPPORT FOR and AGAINST AN ALLGED ASSOCIATION BETWEEN MENTAL ILLNESS & VIOLENCE (2) Empirical investigations: Increased prevalence rates of mental disorder amongst prisoners convicted of violent offences Violence by people with mental disorder Cohort studies

Homicide 50-90% mentally disordered, of which 5-20% psychoses (Erb et al 2001; Fazel & Grann 2004; Gottlieb, Gabrielsen & Kramp 1987; Shaw Appleby & Amos 1999) Prison: One in three prison inmates suffer from serious mental illness (Abrams & Teplin 1991, Blaauw 2002) Recent meta-analysis suggested 4% psychoses, 12% depression, and 46% antisocial PD in prisons (Fazel & Danesh 2002) Among defendants referred for forensic evaluation by courts in Sweden: approx. 40% psychosis, concomitant PD 60% and substance use disorder 55% of the cases (Official statistics, RMV) Prevalence of mental disorders in prisoners

Individuals suffering from schizophrenia; higher risk than general population to commit violent offence (Lindqvist & Allebeck 1990, and a large number of others) 12% of general psychiatric inpatients commit violent acts during the first year after discharge (Walsh et al 2001; Monahan et al 2001) Major mental disorder (incl. schz, major depression and bipolar syndrome) 2-6 times higher risk than healthy controls (Brennan 1996; Eronen et al 1996) An association with deinstitutionalisation? (Mullen et al 2000; 2004) Violence in mentally disordered

” Weak association, does not warrant current legislations ” ” A robust association, but accounted for primarily by concomitant substance use and SES factors ” ” A strong association – and one that is explained by the illness per se, i.e. ’illness drives violence’ ” Mental IllnessViolence ? INTERPRETATION?

IS THE GLASS HALF-FULL or HALF-EMPTY? DEBATE Age- and sex-adjusted relative risk of 4 to 6 times higher to offend violently compared with general population Approx. 90% of mentally ill do not offend violently

POPULATION IMPACT Population attributable risk (PAR) Population attributable risk fraction (PAF)

THE CONTRIBUTION OF MENTAL DISORDER TO VIOLENT CRIME Martin Grann, PhD CPsych, Martin Grann, PhD CPsych, Associate Prof. 1) Honorary Research Fellow 2) Seena Fazel, MB ChB MD MRCPsych Seena Fazel, MB ChB MD MRCPsych, Senior Research Fellow 2), Research affiliate 1) 1) Karolinska Institute Centre for Violence Prevention Stockholm, Sweden 2) Oxford University Dept. of Psychiatry Oxford, U.K.

Population attributable risk DEFINITIONS T M C CM- CM+ Individuals: No of people in the population No of people hospitalised with psych. diagnosis No of people convicted of at least one violent crime People without psych hospitalisations who were convicted People with psych hospitalisations who were convicted M T C

DEFINITIONS (contd.) T M C CM- CM+ No of violent convictions: No of violent convictions of people without psych. admissions No of violent convictions of people with psych. admissions No of violent convictions NCM- NCM+ NC NCNCM+NCM- = +

DEFINITIONS (contd.) is the rate of violent crimes per 1000 persons in the population T r = is the rate of violent crimes per 1000 non-disordered persons NC r 0 = T-M NCM- is the rate of violent crimes per 1000 mentally disordered persons r 1 = M NCM+ RR = r 1 / r 0 is the rate ratio RD = r 1 - r 0 is the rate difference (in rate per 1000) RD% = (r 1 - r 0 ) / r 1 is the rate difference percent (%)

DEFINITIONS (contd.) is the rate of convictions (rate per 1000 offenders) comitted by psychiatric patients T NC T-M NCM- PAR = r-r 0 =- []][ PAF = PAR / r is the % of all convictions in the country comitted by psychiatric patients Population attributable risk fraction Population attributable risk Note: PAR and PAF estimates assume that there is a causal relationship between mental disorder and crime

RESULTS – RAW NUMBERS T M C CM- CM+ Individuals : M = individuals in population >15 441,066 individuals were admitted on at least one occasion for psych. diagnosis 145,860 individuals were convicted of at least one violent crime 111,191 individuals without psych admission were convicted 34,635 individuals with psych admission were convicted M T C

RESULTS – RAW NUMBERS T M C CM- CM+ No of violent crimes : 224,126 violent crimes by people without psych. admissions 114,330 violent crimes by people with psych. admissions total 338,456 violent crimes NCM- NCM+ NC

RESULTS Number of violent crimes per 1000 in the population r = 45 / 1000 No of violent crimes (per 1000 in the population) committed by people identified as mentally disordered via the inpatient register Population attributable risk PAR = 12 (out of 45)

1. Patients with severe mental illness (psychoses) 2. Substance use patients

1.) SEVERE MENTAL ILLNESS Psychoses Psychotic disorders, such as schizophrenia, schizoaffective disorder, bipolar disorder - hallucinations - paranoid ideation - isolation, anhedionia - manic conditions - megalomanic ideation - severe depression - catatonic states

Severe Mental Illness (SMI) by sex and age-bands (Schizophrenia and other psychoses, N = , during ) Fazel & Grann (in press) American Journal of Psychiatry

2.) SUBSTANCE USE DISORDERS Alcohol Drugs such as amphetamine, cocain and heroine ”Legal drugs used illegally” (benzodiazepines eg Rohypnol) Poly-drug use

Alcohol and Drug Use (N = ) Grann & Fazel (2004) BMJ, 328, Any admission for alcohol or drug use: 23.3% 17.6%

Population-based studies SUMMARY The contribution of mentally disordered inpatients to violent offending was much higher than expected Notably, one third of all aggravated assaults, one fourth of all assaults, one fourth of all robberies, and a majority of all homicides were committed by persons who were also psychiatric inpatients at any time during the 13-year study period However, the contribution to violent crime by people suffering from psychotic illnesses was small, approx 5% The by far largest population attributable risk was seen in patients hospitalised for substance misuse disorders, who committed 1 in 4 of all violent crimes.

CONCLUSION It makes sense to target the alcohol and drug clients for risk assessment and violence prevention programmes!