bs_bs_banner
R E V I E W
Drug and Alcohol Review (January 2015), 34, 46–50 DOI: 10.1111/dar.12179
BRIEF REPORT
Substance use and risk of death in young offenders: A prospective data linkage study STUART A. KINNER1,2,3,4, LOUISA DEGENHARDT1,2,5,6, CAROLYN COFFEY2, STEPHEN HEARPS2, MATTHEW SPITTAL1, SUSAN M. SAWYER2,7,8 & GEORGE C. PATTON2,7,8 1
Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia, 2Centre for Adolescent Health, Murdoch Childrens Research Institute, Melbourne, Australia, 3School of Medicine, University of Queensland, Brisbane, Australia, 4School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia, 5National Drug and Alcohol Research Centre, University of New South Wales Australia, Sydney, Australia, 6 Department of Global Health, School of Public Health, University of Washington, Seattle, USA, 7Department of Paediatrics, University of Melbourne, Melbourne, Australia, and 8Centre for Adolescent Health, Royal Children’s Hospital Centre for Adolescent Health, Melbourne, Australia
Abstract Introduction and Aims. Young offenders are at increased risk of preventable death after release from custody, but risk factors for death in this population are poorly understood. Despite their poor health profiles, no studies have examined mortality outcomes in young people who have served community-based orders. The aims of this study were to describe the causes and identify risk factors for death in a cohort of young offenders in Victoria, Australia. Design and Methods. We interviewed young people serving a custodial (n = 273) or community-based order (n = 242) in Victoria, Australia in 2002–2003. Measures included demographics and family history, offence history, experience of victimisation, mental illness, self-harm and substance use. Deaths up to 31 December 2011 were identified through a probabilistic linkage with the National Death Index. Results. The all-cause crude mortality rate was 4.2 (95% confidence interval 2.7–6.8) per 1000 person years and was not significantly different for those who had served custodial and community-based orders. Most deaths were due to drug overdose, traffic accidents or suicide. Adjusting for age, sex and order type, risk factors for death from the baseline interview included weekly use of opioids, sleeping pills or painkillers, polydrug use and injecting drug use. Discussion and Conclusions. Young people who have served community-based and custodial orders are at an increased risk of preventable death. Those engaging in risky substance use, particularly injecting drug use and use of multiple central nervous system depressants, are at greatest risk. There is an urgent need to develop and rigorously evaluate preventive interventions. [Kinner SA, Degenhardt L, Coffey C, Hearps S, Spittal M, Sawyer SM, Patton GC. Substance use and risk of death in young offenders: A prospective data linkage study. Drug Alcohol Rev 2015;34:46–50] Key words: mortality, youth offender, substance abuse, suicide, injecting drug use.
Introduction Adults have an elevated risk of death after release from custody. In most studies, drug overdose, suicide and injury are the leading causes [1,2]. Among adult ex-prisoners, young people aged 18–24 experience a
greater elevation in risk of death, relative to agematched peers, than their older counterparts [3]. Despite this, few studies have examined mortality in young offenders. In a small Swedish study of youth sent to probationary school in 1967 and followed until 1985, the
Stuart A. Kinner PhD, Principal Research Fellow, Louisa Degenhardt PhD, NHMRC Principal Research Fellow, Carolyn Coffey PhD, Senior Research Officer, Stephen Hearps PGDipPsyc, Data Coordinator, Matthew Spittal PhD, Senior Research Fellow, Susan M. Sawyer MD, Director, George C. Patton MD, Director of Research. Correspondence to Associate Professor Stuart A. Kinner, Melbourne School of Population and Global Health, University of Melbourne, 207 Bouverie Street, Carlton Vic. 3010 Australia. Tel: +61 3 9035 7598; Fax: +61 3 9348 1174; E-mail: [email protected] Received 31 March 2014; accepted for publication 28 May 2014. © 2014 Australasian Professional Society on Alcohol and other Drugs
Mortality in young offenders
majority of observed deaths were due to accidents, suicide and substance-related causes [4]. In a registerbased study of almost 1 million Swedish adults, the risk of suicide was greater for those convicted of a crime between the ages of 15 and 19, even after adjustment for measured confounders [5]. An Australian study of youth after their first custodial sentence observed a mortality rate similar to that in adult ex-prisoners, and the leading causes of death were drug-related, suicide and injuries. Risk factors included early age at first detention, multiple detentions and drug-related offences [6,7]. By contrast, among young male parolees in the USA, more than half of the observed deaths were due to homicide. Identified risk factors included a documented history of drug abuse, gang involvement or institutional violence, and residing in Los Angeles [8]. Two studies in the USA have followed cohorts of previously incarcerated young people prospectively. Among 118 formerly incarcerated young offenders, Yeager and Lewis identified seven deaths by age 25 due to overdose, violence, traffic accidents and suicide [9]. Among 1829 pre-trial youth detainees, Teplin and colleagues observed 65 deaths and a mortality rate more than four times that of age- and sex-matched community peers; almost all deaths (96%) were due to homicide or legal intervention (police shooting) [10]. Most studies to date have relied on retrospective linkage with routinely collected data that usually provide little information on the personal and social characteristics of individuals, thus limiting their capacity to inform preventive efforts. In addition, studies have focused exclusively on young people who have been released from custody despite evidence of very poor health profiles in young people serving noncustodial (community-based) orders [11]. The aim of this study was to identify risk and protective factors for death in a cohort of young people in contact with the youth justice system in Victoria, Australia in 2002–2003.
Methods Baseline survey Between 27 May 2002 and 1 October 2003, we interviewed sentenced young offenders serving a community-based or custodial order in Victoria, Australia. In the custody arm, sampling occurred in all three Victorian Juvenile Justice centres. In the communitybased order arm, participants were recruited from all Melbourne metropolitan regions and one rural region. Potential participants had the nature and implications of the study explained to them and provided written, informed consent. Interviews typically took 30–60 min to complete. The baseline survey was approved by the
47
Human Research Ethics Committees of the Victorian Department of Human Services and the Royal Children’s Hospital, Melbourne. The survey measured demographics, educational and vocational experiences, violence and sexual assault, offence history, and family history of mental illness and imprisonment. Depression symptoms in the past two weeks were assessed using the Short Mood and Feelings Questionnaire [12]; psychosis symptoms were assessed using the six-item Psychosis Screening Questionnaire [13]. Participants who indicated that they had deliberately harmed themselves in the past six months were asked to describe what they did. Responses were post-coded by a psychiatrist and a clinical psychologist into definite self-harm with or without suicidal intent [14]. Hazardous drinking was measured using the Alcohol Use Disorders Identification Test-Alcohol Consumption Questions, a three-item measure of usual quantity and frequency of alcohol consumption [15]. Frequency of illicit drug use in the past six months was assessed by self-report. Those reporting non-medical use of three or more illicit drug types (cannabis, heroin, amphetamines, sleeping pills, cocaine, inhalants, painkillers, natural hallucinogens, LSD, ecstasy) were defined as engaging in polydrug use.The cohort, survey methods and measures have been described in more detail elsewhere [11]. Linkage with mortality data Participant identities were linked probabilistically with the National Death Index by the Australian Institute of Health and Welfare. The National Coronial Information System provided underlying and contributing causes of death based on ICD-10 codes, up to 31 December 2011. The linkage component of the study was approved by the Australian Institute of Health and Welfare Ethics Committee and the Coroners Court of Victoria Research Committee. Data analysis We compared custodial and community-based offenders on demographic, educational, familial and offending characteristics.We grouped causes of death into five widely used and mutually exclusive categories based on ICD-10 underlying cause of death codes [16]: accidental poisoning, intentional self-harm, transport accident, assault and other causes. Person time was calculated from the day of interview to death or end of follow-up. Consistent with previous studies, we calculated allcause crude mortality rates (CMR) per 1000 person years (py). We selected potential predictors from those that could plausibly have a causal association with death and, using Cox proportional hazards regression, © 2014 Australasian Professional Society on Alcohol and other Drugs
48
S. A. Kinner et al.
computed adjusted hazard ratios for all-cause mortality, adjusting for age, sex and order type (custodial vs. community-based order). Results The characteristics of the sample are presented in Table 1 according to order type. The mean age of participants at baseline was 17.3 years, and the median length of follow-up was 8.9 years. At baseline, a large proportion of participants had poor educational attainment and reported that a family member had experienced drug or alcohol problems, mental illness or incarceration. One in four participants had been convicted of a drug-related offence. Differences between the community-based order and custodial groups are discussed in more detail elsewhere [11]. Across the full cohort, we observed 19 deaths in 4531 py of observation, giving an all-cause CMR of 4.19 per 1000 py [95% confidence interval (CI) 2.67– 6.75]. The leading causes of death were accidental poisoning (n = 6), transport accidents (n = 5) and intentional self-harm (n = 4). Three deaths were still subject to coronial inquiry, and as such, cause of death was unavailable. There was a non-significant trend for all-cause CMR to be higher among those who had served a custodial order (CMR = 5.00 per 1000 py,
95% CI 2.83–8.80) than among those who had served a community-based order (CMR = 3.29 per 1000 py, 95% CI 1.57–6.89). Table 2 presents the hazard ratio for all-cause death according to selected baseline characteristics adjusted for sex, age and order type. Those reporting at least weekly use of opiates, sleeping pills or painkillers at baseline, those reporting recent polydrug use and those reporting injection drug use in the past year were at increased risk of death. Risky drinking at baseline was protective. Discussion Among young people who had served an order under the youth justice system in Victoria, Australia, we observed a CMR of 4.2 per 1000 py. This is lower than that reported in previous studies of detained youth in Australia (CMR = 7.2 per 1000 py) and the USA (CMR = 8.0 per 1000 py) but is still almost four times higher than among age- and sex-matched peers in the Australian community (CMR = 1.1 per 1000 py) [6]. One explanation for the lower mortality rate observed in this study may relate to shifts in illicit drug markets, with heroin-related mortality in Australia dropping significantly following the onset of a sustained heroin shortage in 2001 [17].
Table 1. Sample characteristics by order type Community-based order (n = 242)
Custodial order (n = 273)
Pa
16.3 (1.0) 9.2 (3.8) 8.8 (0.4–9.6)
18.2 (1.6) 9.5 (11.5) 8.9 (1.1–9.6)
R E V I E W
Drug and Alcohol Review (January 2015), 34, 46–50 DOI: 10.1111/dar.12179
BRIEF REPORT
Substance use and risk of death in young offenders: A prospective data linkage study STUART A. KINNER1,2,3,4, LOUISA DEGENHARDT1,2,5,6, CAROLYN COFFEY2, STEPHEN HEARPS2, MATTHEW SPITTAL1, SUSAN M. SAWYER2,7,8 & GEORGE C. PATTON2,7,8 1
Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia, 2Centre for Adolescent Health, Murdoch Childrens Research Institute, Melbourne, Australia, 3School of Medicine, University of Queensland, Brisbane, Australia, 4School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia, 5National Drug and Alcohol Research Centre, University of New South Wales Australia, Sydney, Australia, 6 Department of Global Health, School of Public Health, University of Washington, Seattle, USA, 7Department of Paediatrics, University of Melbourne, Melbourne, Australia, and 8Centre for Adolescent Health, Royal Children’s Hospital Centre for Adolescent Health, Melbourne, Australia
Abstract Introduction and Aims. Young offenders are at increased risk of preventable death after release from custody, but risk factors for death in this population are poorly understood. Despite their poor health profiles, no studies have examined mortality outcomes in young people who have served community-based orders. The aims of this study were to describe the causes and identify risk factors for death in a cohort of young offenders in Victoria, Australia. Design and Methods. We interviewed young people serving a custodial (n = 273) or community-based order (n = 242) in Victoria, Australia in 2002–2003. Measures included demographics and family history, offence history, experience of victimisation, mental illness, self-harm and substance use. Deaths up to 31 December 2011 were identified through a probabilistic linkage with the National Death Index. Results. The all-cause crude mortality rate was 4.2 (95% confidence interval 2.7–6.8) per 1000 person years and was not significantly different for those who had served custodial and community-based orders. Most deaths were due to drug overdose, traffic accidents or suicide. Adjusting for age, sex and order type, risk factors for death from the baseline interview included weekly use of opioids, sleeping pills or painkillers, polydrug use and injecting drug use. Discussion and Conclusions. Young people who have served community-based and custodial orders are at an increased risk of preventable death. Those engaging in risky substance use, particularly injecting drug use and use of multiple central nervous system depressants, are at greatest risk. There is an urgent need to develop and rigorously evaluate preventive interventions. [Kinner SA, Degenhardt L, Coffey C, Hearps S, Spittal M, Sawyer SM, Patton GC. Substance use and risk of death in young offenders: A prospective data linkage study. Drug Alcohol Rev 2015;34:46–50] Key words: mortality, youth offender, substance abuse, suicide, injecting drug use.
Introduction Adults have an elevated risk of death after release from custody. In most studies, drug overdose, suicide and injury are the leading causes [1,2]. Among adult ex-prisoners, young people aged 18–24 experience a
greater elevation in risk of death, relative to agematched peers, than their older counterparts [3]. Despite this, few studies have examined mortality in young offenders. In a small Swedish study of youth sent to probationary school in 1967 and followed until 1985, the
Stuart A. Kinner PhD, Principal Research Fellow, Louisa Degenhardt PhD, NHMRC Principal Research Fellow, Carolyn Coffey PhD, Senior Research Officer, Stephen Hearps PGDipPsyc, Data Coordinator, Matthew Spittal PhD, Senior Research Fellow, Susan M. Sawyer MD, Director, George C. Patton MD, Director of Research. Correspondence to Associate Professor Stuart A. Kinner, Melbourne School of Population and Global Health, University of Melbourne, 207 Bouverie Street, Carlton Vic. 3010 Australia. Tel: +61 3 9035 7598; Fax: +61 3 9348 1174; E-mail: [email protected] Received 31 March 2014; accepted for publication 28 May 2014. © 2014 Australasian Professional Society on Alcohol and other Drugs
Mortality in young offenders
majority of observed deaths were due to accidents, suicide and substance-related causes [4]. In a registerbased study of almost 1 million Swedish adults, the risk of suicide was greater for those convicted of a crime between the ages of 15 and 19, even after adjustment for measured confounders [5]. An Australian study of youth after their first custodial sentence observed a mortality rate similar to that in adult ex-prisoners, and the leading causes of death were drug-related, suicide and injuries. Risk factors included early age at first detention, multiple detentions and drug-related offences [6,7]. By contrast, among young male parolees in the USA, more than half of the observed deaths were due to homicide. Identified risk factors included a documented history of drug abuse, gang involvement or institutional violence, and residing in Los Angeles [8]. Two studies in the USA have followed cohorts of previously incarcerated young people prospectively. Among 118 formerly incarcerated young offenders, Yeager and Lewis identified seven deaths by age 25 due to overdose, violence, traffic accidents and suicide [9]. Among 1829 pre-trial youth detainees, Teplin and colleagues observed 65 deaths and a mortality rate more than four times that of age- and sex-matched community peers; almost all deaths (96%) were due to homicide or legal intervention (police shooting) [10]. Most studies to date have relied on retrospective linkage with routinely collected data that usually provide little information on the personal and social characteristics of individuals, thus limiting their capacity to inform preventive efforts. In addition, studies have focused exclusively on young people who have been released from custody despite evidence of very poor health profiles in young people serving noncustodial (community-based) orders [11]. The aim of this study was to identify risk and protective factors for death in a cohort of young people in contact with the youth justice system in Victoria, Australia in 2002–2003.
Methods Baseline survey Between 27 May 2002 and 1 October 2003, we interviewed sentenced young offenders serving a community-based or custodial order in Victoria, Australia. In the custody arm, sampling occurred in all three Victorian Juvenile Justice centres. In the communitybased order arm, participants were recruited from all Melbourne metropolitan regions and one rural region. Potential participants had the nature and implications of the study explained to them and provided written, informed consent. Interviews typically took 30–60 min to complete. The baseline survey was approved by the
47
Human Research Ethics Committees of the Victorian Department of Human Services and the Royal Children’s Hospital, Melbourne. The survey measured demographics, educational and vocational experiences, violence and sexual assault, offence history, and family history of mental illness and imprisonment. Depression symptoms in the past two weeks were assessed using the Short Mood and Feelings Questionnaire [12]; psychosis symptoms were assessed using the six-item Psychosis Screening Questionnaire [13]. Participants who indicated that they had deliberately harmed themselves in the past six months were asked to describe what they did. Responses were post-coded by a psychiatrist and a clinical psychologist into definite self-harm with or without suicidal intent [14]. Hazardous drinking was measured using the Alcohol Use Disorders Identification Test-Alcohol Consumption Questions, a three-item measure of usual quantity and frequency of alcohol consumption [15]. Frequency of illicit drug use in the past six months was assessed by self-report. Those reporting non-medical use of three or more illicit drug types (cannabis, heroin, amphetamines, sleeping pills, cocaine, inhalants, painkillers, natural hallucinogens, LSD, ecstasy) were defined as engaging in polydrug use.The cohort, survey methods and measures have been described in more detail elsewhere [11]. Linkage with mortality data Participant identities were linked probabilistically with the National Death Index by the Australian Institute of Health and Welfare. The National Coronial Information System provided underlying and contributing causes of death based on ICD-10 codes, up to 31 December 2011. The linkage component of the study was approved by the Australian Institute of Health and Welfare Ethics Committee and the Coroners Court of Victoria Research Committee. Data analysis We compared custodial and community-based offenders on demographic, educational, familial and offending characteristics.We grouped causes of death into five widely used and mutually exclusive categories based on ICD-10 underlying cause of death codes [16]: accidental poisoning, intentional self-harm, transport accident, assault and other causes. Person time was calculated from the day of interview to death or end of follow-up. Consistent with previous studies, we calculated allcause crude mortality rates (CMR) per 1000 person years (py). We selected potential predictors from those that could plausibly have a causal association with death and, using Cox proportional hazards regression, © 2014 Australasian Professional Society on Alcohol and other Drugs
48
S. A. Kinner et al.
computed adjusted hazard ratios for all-cause mortality, adjusting for age, sex and order type (custodial vs. community-based order). Results The characteristics of the sample are presented in Table 1 according to order type. The mean age of participants at baseline was 17.3 years, and the median length of follow-up was 8.9 years. At baseline, a large proportion of participants had poor educational attainment and reported that a family member had experienced drug or alcohol problems, mental illness or incarceration. One in four participants had been convicted of a drug-related offence. Differences between the community-based order and custodial groups are discussed in more detail elsewhere [11]. Across the full cohort, we observed 19 deaths in 4531 py of observation, giving an all-cause CMR of 4.19 per 1000 py [95% confidence interval (CI) 2.67– 6.75]. The leading causes of death were accidental poisoning (n = 6), transport accidents (n = 5) and intentional self-harm (n = 4). Three deaths were still subject to coronial inquiry, and as such, cause of death was unavailable. There was a non-significant trend for all-cause CMR to be higher among those who had served a custodial order (CMR = 5.00 per 1000 py,
95% CI 2.83–8.80) than among those who had served a community-based order (CMR = 3.29 per 1000 py, 95% CI 1.57–6.89). Table 2 presents the hazard ratio for all-cause death according to selected baseline characteristics adjusted for sex, age and order type. Those reporting at least weekly use of opiates, sleeping pills or painkillers at baseline, those reporting recent polydrug use and those reporting injection drug use in the past year were at increased risk of death. Risky drinking at baseline was protective. Discussion Among young people who had served an order under the youth justice system in Victoria, Australia, we observed a CMR of 4.2 per 1000 py. This is lower than that reported in previous studies of detained youth in Australia (CMR = 7.2 per 1000 py) and the USA (CMR = 8.0 per 1000 py) but is still almost four times higher than among age- and sex-matched peers in the Australian community (CMR = 1.1 per 1000 py) [6]. One explanation for the lower mortality rate observed in this study may relate to shifts in illicit drug markets, with heroin-related mortality in Australia dropping significantly following the onset of a sustained heroin shortage in 2001 [17].
Table 1. Sample characteristics by order type Community-based order (n = 242)
Custodial order (n = 273)
Pa
16.3 (1.0) 9.2 (3.8) 8.8 (0.4–9.6)
18.2 (1.6) 9.5 (11.5) 8.9 (1.1–9.6)
