LONG-TERM TREATMENT OUTCOME: WHAT ARE THE 11 YEAR OUTCOMES OF TREATMENT FOR HEROIN DEPENDENCE?

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1 AUSTRALIAN T R E A T M E N T OU T C O M E STUDY - N S W Funded by the National Health and Medical Research Council and the Australian Government Department of Health. ATOS NSW is a project of the Centre of Research Excellence in Mental Health and Substance Use, and the National Drug and Alcohol Research Centre. ISSUE NO. 7, SEPTEMBER 2014 LONG-TERM TREATMENT OUTCOME: WHAT ARE THE 11 YEAR OUTCOMES OF TREATMENT FOR HEROIN DEPENDENCE? KEY POINTS There had been universal treatment exposure since baseline, and 47% were enrolled in treatment at 11-years. There were substantial, and sustained, reductions in heroin use across follow-up. At 11-years, 75% were heroin abstinent. Annual heroin overdose rates declined from 25% at baseline to 5% at 11-years. There were similar declines in injection rates and needle sharing. Crime rates declined at each successive follow-up, reflecting the declines in drug use. At baseline 55% had recently committed a crime, compared to 22% at 11-years. While there were improvements in psychological health, 25% had severe psychiatric problems at 11-years. Although the overall physical health of the cohort had improved since baseline, there was a decline in general physical health of the cohort between 36-months and 11-years, with 10% experiencing severe physical health problems. However, there was a substantial decrease in injection-related health problems from 74% at baseline to 24% by 11-years. ATOS has demonstrated that 11-years after entering treatment for heroin dependence, there are substantial reductions in drug use, criminality and injection-related health problems. WHAT IS ATOS? Heroin remains the major clinical problem for agencies treating illicit drug problems in Australia. The Australian Treatment Outcomes Study (ATOS) is a longitudinal cohort study of entrants to treatment for heroin dependence, conducted in NSW, SA and VIC. In NSW, 615 participants were recruited from 19 agencies treating heroin dependence in the greater Sydney region. The agencies comprised methadone/buprenorphine maintenance agencies (MT), drug free residential rehabilitation agencies (RR) and detoxification facilities (DTX). A group of heroin users not currently in treatment (NT) were also recruited from needle and syringe programmes. The ATOS baseline sample was predominantly male, in their late twenties and had been using heroin for a decade. Few were in full-time employment, and 1 there was extensive prison experience. Almost all (90%) had previous treatment histories. Previous Bulletins have reported on baseline 1 2 characteristics, 3-month follow-up, 12-month 3 4 follow-up, 24-month follow-up, 36-month follow 5 -up, and the costs associated with treatment and 6 health service utilization. The current Bulletin reports on the NSW cohort at 11-years after commencement of the study. More specific details on the cohort at baseline, 3-, 12-, 24-, and 36- months are presented in a range of scientific 7-15 papers.

2 WHO WAS FOLLOWED UP? Follow-up rates at each point were high: 3-month (89%), 12-months (80%), 24-months (76%), and 36-months (70%). At 11-years 431 individuals were re-interviewed (70%), a further 7 (4%) were incarcerated and 63 (10%) were deceased. The majority of the cohort (over 91%) was located at 11-years. WHAT WAS THEIR TREATMENT EXPOSURE? Treatment exposure over 11-years was extensive. Of those interviewed at 11-years, 47% were currently enrolled in a treatment programme, including 60% of males and 40% of females. By follow-up, the entire baseline non-treatment group had experienced treatment for heroin dependence over that period, and 37% were currently enrolled in treatment. Overall, the cohort had received a median of 1,465 treatment days over 11-years, over a median of 4 different treatment episodes. There was substantial movement between treatment modalities over time. Of those who commenced in MT, 36% had a subsequent enrolment in DTX and 28% in RR. Similarly, of those who commenced in DTX, 70% had subsequent MT experience and 49% enrolled in RR. Finally, of those who commenced in RR, 67% had subsequent MT experience, and 55% a subsequent DTX. HAS HEROIN USE CHANGED? The positive effects of treatment were demonstrated in the substantial reductions seen in heroin use over 11-years (Figure 1). Daily heroin use had declined sharply from 80% at baseline to 24% by 3-months, declined again to 17% at 12-months, where it remained fairly stable to 36-months. By 11-years however, daily heroin use had further declined to 4%. Current heroin abstinence was 49% by 3-months, and increased to over half of the cohort at all subsequent follow-ups. By 11-years, three-quarters of this group of long-term heroin users were currently heroin abstinent. As with heroin use, there was a substantial reduction in heroin dependence over the follow-up period. Whilst almost the entire cohort was heroin dependent at baseline, by 11-years, this had reduced to 15% (Figure 2). Similar to heroin use, the sharpest declines in heroin dependence were evident from baseline to 3-months. In contrast however, the use of other drugs remained fairly high throughout the follow-up period. Whilst there was a reduction in other drug use from baseline to 36-months, this was not maintained to 11-years, which saw an increase from 77% at 36-months, to 85% at 11-years (Figure 2). Figure 1. Heroin use in preceding month

3 Figure 2. Past month heroin use, dependence and other drug use HAS THERE BEEN A CHANGE IN RISK-TAKING BEHAVIOURS? As with heroin use and dependence, daily injecting declined dramatically over the first 3-months, declining still further at the 12-, 24-, and 36-month follow-ups (Figure 3). By 11-years, only 10% were injecting daily, compared to 79% at baseline. Borrowing used syringes declined from one in five of the cohort at baseline to approximately one in forty by 11-years. Critically, in terms of risk of death, annual heroin overdose rates declined over each subsequent year. In the year prior to the commencement of ATOS, 24% had overdosed, compared to only 5% at 11-years. Figure 3. Risk-taking behaviours at baseline and 11-years HAS THERE BEEN A CHANGE IN LEVEL OF CRIME? Consistent with the large declines in heroin use and injecting, levels of criminal involvement declined from baseline to 11-years. As with heroin use and dependence, the sharpest decline occurred at 3-months. The reduced impact on society is evident by the fact that 55% had committed crime in the month prior to the commencement of ATOS, compared to 22% at 11-years. Although there was a slight increase in criminal involvement between 36-months and 11-years, it was not statistically significant. Importantly, at baseline, almost one-quarter of the cohort indicated their main source of income was obtained from criminal activity. At 11-years, this had dramatically reduced to just 2.1% (Figure 4). Figure 4. Proportions committing crime, and reporting crime as a main source of income in preceding month Note: 3mth follow-up not applicable for annual overdose rate

4 HAS THERE BEEN A CHANGE IN PSYCHOLOGICAL HEALTH? Although there were substantial and sustained declines in heroin use and crime, the psychological health of the cohort had substantially worsened (Figures 5 and 6). Whilst the overall mental health of the cohort had improved dramatically from baseline to 36-months, by 11-years, general mental health had substantially declined and remained very poor compared to the general population (Figure 6). At baseline, 49% were categorised as having severe mental health problems compared to 19% at 36-months, and 25% at 11-years. Despite improvements over the course of the study, poor psychological health remained a problem for large proportions of the cohort. Figure 5. Current major depression diagnosis At baseline, a quarter of the cohort had a current diagnosis of major depression (Figure 5). This proportion was halved by 3-months, and declined at each subsequent point to 36-months, where 8% met criteria for a diagnosis. However, by 11-years, current depression had sharply increased, to the point where one in five met criteria for current major depression. More than one third of the cohort had a diagnosis of lifetime post-traumatic stress disorder (PTSD) at baseline, with almost one third of the cohort having experienced symptoms in the 12-months prior to the commencement of ATOS. At 11-years, one-fifth of the cohort had a diagnosis of current PTSD, with 74% experiencing a trauma at some point during the follow-up period. Figure 6. Mental health (severe disability)

5 HAS THERE BEEN A CHANGE IN PHYSICAL HEALTH? The physical health of the cohort at baseline was well below the population average, although not nearly as poor as mental heath. Whilst overall physical health and improved from baseline to 36-months to the point where the cohort paralleled the health of the general population, by 11-years, physical health had substantially declined. At baseline 9% were categorised as having sever physical disability (Figure 7), which reduced to 7% by 36-months. By 11-years however, more than 10% of the cohort were categorised as having severe physical disability, which was not only higher than the previous follow-up, but higher than baseline levels. Figure 7. Physical health (severe disability) WHAT HAVE WE LEARNED FROM ATOS? As with previous ATOS Bulletins, there is no certainty that there will be another issue, as secure funding to maintain the cohort has not been obtained. As the only cohort study of its kind in Australia, what have we learned from ATOS? Firstly, longitudinal research among heroin users in Australia is possible. Prior to ATOS, the ability to maintain a longitudinal substance-dependent cohort was uncertain. Not only have ATOS follow-up rates remained at, and exceeded international standards, but the most recent follow-up rates exceeded those from the previous follow-up, despite there being no contact with participants in the intervening eight years. Astoundingly, more than 90% of the cohort was accounted for at 11-years. As such, we have learned from ATOS that it is possible to investigate the natural history of heroin users. A decline in injection rates was accompanied by a marked reduction in injection-related health problems. As with heroin use and dependence, the sharpest decrease occurred in the first 3-months, but there were further declines at subsequent follow-up points. While 74% had injection-related health problems at baseline, reflecting high rates of daily injecting, this had dropped to 24% by 11-years. Figure 8. Current injection-related health problems Secondly, the study has documented the penetration of treatment amongst the heroin using populations, particularly given that the entire non-treatment group had subsequently enrolled in treatment at some point during the 11-year follow-up. Treatment experience of the cohort was extensive and heroin users moved freely between different modalities of treatment. Treatments are not separated into different streams in Australia. Thirdly, there were substantial improvements in heroin use and dependence, risk-taking, and crime, which were maintained over 11-years. These improvements, however, were not similarly reflected in the physical or psychological health of the cohort. Comorbid psychiatric disorders present a major clinical challenge to treatment agencies, perhaps more so than the challenges presented by alcohol or other drugs. ATOS has made a substantial contribution to the international literature on the treatment of heroin dependence. It has also provided solid outcome data to treatment agencies, which supports their substantial efforts to treat a difficult problem. To summarise the findings of ATOS in a single sentence, treatment for heroin dependence is a long-term process, which leads to clear and sustained benefits to both heroin users and society.

6 REFERENCES ATOS Bulletin (NSW). Who attends for heroin treatment?: Baseline findings of ATOS in NSW. Issue No. 1, November ATOS Bulletin (NSW). What are the short-term outcomes of treatment for heroin dependence?: 3 month follow-up results. Issue No. 2., June ATOS Bulletin (NSW). What are the 12-month outcomes of treatment for heroin dependence? Issue No. 3., November ATOS Bulletin (NSW). What are the 24 month outcomes of treatment for heroin dependence? Issue No. 5., March 2005 ATOS Bulletin (NSW). Long term treatment outcome: What are the 36-month outcomes of treatment for heroin dependence? Issue no. 6., March 2006 ATOS Bulletin (NSW). Costs and health service use associated with the treatment of heroin dependence. Issue No. 4, September Darke, S., Ross, J., Teesson, M., Ali, R., Cooke, R., Ritter, A. & Lynskey, M. (2005) Factors associated with 12 months continuous heroin abstinence: findings from the Australian Treatment Outcome Study (ATOS). Journal of Substance Abuse Treatment, 28, Darke, S., Williamson, A., Ross, J. & Teesson, M. (2006) Residential rehabilitation for the treatment of heroin dependence: sustained heroin abstinence and drug-related problems two years after treatment entrance. Addictive Disorders and Their Treatment, 5; Treatment Outcome Study (ATOS). Drug and Alcohol Review, 24, Ross, J., Teesson M., Darke S., Lynskey M., Ali R., Ritter A. & Cooke R. (2006) Short-term outcomes for the treatment of heroin dependence: findings from Australian Treatment Outcome Study (ATOS). Addictive Disorders and Their Treatment, 5; Teesson, M., Ross, J., Darke, S., Lynskey, M., Ali, R., Cooke, R. & Ritter A. (2006) The Australian Treatment Outcome Study (ATOS): 1 year follow-up results. Drug and Alcohol Dependence, 2; Teesson, M., Mills, K., Ross, J., Darke, S., Williamson, A., Havard, A. (2008) The impact of treatment on 3 years' outcome for heroin dependence: findings from the Australian Treatment Outcome Study (ATOS). Addiction, 103; Darke, S., Ross, J., Williamson, A., Mills, K.L., Havard, A., Teesson, M. (2007) Patterns and correlates of attempted suicide by heroin users over a 3-year period: Findings from the Australian treatment outcome study, Drug and Alcohol Dependence, 87; Darke, S., Ross, J., Teesson, M. (2007) The Australian Treatment Outcome Study (ATOS): what have we learnt about treatment for heroin dependence? Drug and Alcohol Review, 26; Mills, K.L., Teesson, M., Ross, J., Darke, S. (2007) The impact of post traumatic stress disorder on treatment outcomes for heroin dependence, Addiction, 102; Ross, J., Teesson, M., Darke, S., Lynskey, M., Ali, R., Ritter, A. & Cooke, R. (2005) The characteristics of heroin users entering treatment: findings from the Australian