Remission from drug abuse over a 25-year period: patterns of remission and treatment use

Is the relapse concept in studies of substance use disorders a 'one size fits all' concept? A systematic review of relapse operationalisations

ISSUES

Relapse is a theoretical construct and empirical object of inquiry. It is unclear how relapse is operationalised with regard to the various phases in substance use disorders (SUD). The aim was to investigate relapse operationalisations in SUDs studies after short- and long-term abstinence and remission, recovery and slip/lapse.

APPROACH

Systematic review using the following databases: Epistemonikos, Cochrane Central Register of Controlled Trials (CENTRAL and DARE), MEDLINE, EMBASE, Google Scholar, CINAHL, Web of Science and PsycINFO. Search returned 3426 articles, with 276 meeting the following inclusion criteria: empirical study published in English in a peer-reviewed journal; samples meet diagnostic criteria for dependence syndrome or moderate-severe drug use disorder or alcohol use disorder; reports relapse, abstinence, recovery, remission, slip or lapse. Review protocol registration: PROSPERO (CRD42020154062).

KEY FINDINGS

Thirty-two percent of the studies had no definition of 'relapse'. Most relapse operationalisations were defined according to measure (26%), time (17%), use (26%) and amount and frequency (27%). Of the 16 studies with a follow-up duration of up to 2 years, one (6%) contained a definition of 'long-term abstinence'. Of the 64 studies with a follow-up duration of more than 2 years, four (6%) contained a definition of 'long-term abstinence'. Of those, one (2%) mentioned 'early relapse' and one (2%) mentioned 'late relapse'.

IMPLICATIONS

Future research is needed to explore the possible difference between early and late relapse. Moreover, working to increase consensus on relapse operationalisations in SUD research is warranted.

CONCLUSIONS

We identified no consensus on relapse operationalisations nor agreement on the differentiation between early and late relapse. The clinical utility of current relapse operationalisations seems low and may compromise knowledge accumulation about relapse and implementation of research into treatment.

Substance use disorder patients’ expectations on transition from treatment to post-discharge period

Aim:

There is limited knowledge about how inpatients anticipate factors that facilitate the transition between specialised inpatient treatment for substance use disorder (SUD) and the post-discharge period. This study explores factors that inpatients anticipated would facilitate such a transition period.

Method:

A focus group study, consisting of four group interviews with individuals in inpatient SUD treatment, was conducted to explore their expectations for the transition and post-discharge period ahead of them. The transcribed interview material was analysed using thematic analysis.

Findings:

The analytical process led to three themes: “Belonging”, “Intrapersonal processes” and “Predictability”. Correspondence between inpatients’ expectations and the services they are offered in the transition and post-discharge period may serve as proper support for inpatients ahead of a vulnerable phase, such as the transition and post-discharge period.

Conclusions:

Findings from the current study highlight overarching elements that inpatients envisioned to be facilitating, such as social support, motivation, self-efficacy, self-awareness and predictability in basic elements such as employment, housing and personal finances. Findings from this study and previous ones imply that certain factors appear to facilitate in vulnerable phases, such as service level transitions. These facilitating factors should be taken into consideration and used as steppingstones through the transition and post-discharge period after inpatient SUD treatment.

21st century neurobehavioral theories of decision making in addiction: Review and evaluation

This review critically examines neurobehavioral theoretical developments in decision making in addiction in the 21st century. We specifically compare each theory reviewed to seven benchmarks of theoretical robustness, based on their ability to address: why some commodities are addictive; developmental trends in addiction; addiction-related anhedonia; self-defeating patterns of behavior in addiction; why addiction co-occurs with other unhealthy behaviors; and, finally, means for the repair of addiction. We have included only self-contained theories or hypotheses which have been developed or extended in the 21st century to address decision making in addiction. We thus review seven distinct theories of decision making in addiction: learning theories, incentive-sensitization theory, dopamine imbalance and systems models, opponent process theory, strength models of self-control failure, the competing neurobehavioral decision systems theory, and the triadic systems theory of addiction. Finally, we have directly compared the performance of each of these theories based on the aforementioned benchmarks, and highlighted key points at which several theories have coalesced.

Cannabis use patterns and motives: A comparison of younger, middle-aged, and older medical cannabis dispensary patients

INTRODUCTION

Medical cannabis is increasingly being used for a variety of health conditions as more states implement legislation permitting medical use of cannabis. Little is known about medical cannabis use patterns and motives among adults across the lifespan.

METHODS

The present study examined data collected at a medical cannabis dispensary in San Francisco, California. Participants included 217 medical cannabis patients who were grouped into age-defined cohorts (younger: 18-30, middle-aged: 31-50, and older: 51-72). The age groups were compared on several measures of cannabis use, motives and medical conditions using one-way ANOVAs, chi-square tests and linear regression analyses.

RESULTS

All three age groups had similar frequency of cannabis use over the past month; however, the quantity of cannabis used and rates of problematic cannabis use were higher among younger users relative to middle-aged and older adults. The association between age and problematic cannabis use was moderated by age of regular use initiation such that earlier age of regular cannabis use onset was associated with more problematic use in the younger users, but not among older users. Middle-aged adults were more likely to report using medical cannabis for insomnia, while older adults were more likely to use medical cannabis for chronic medical problems such as cancer, glaucoma and HIV/AIDS. Younger participants reported cannabis use when bored at a greater rate than middle-aged and older adults.

CONCLUSIONS

Findings suggest that there is an age-related risk for problematic cannabis use among medical cannabis users, such that younger users should be monitored for cannabis use patterns that may lead to deleterious consequences.

Reaching hepatitis C virus elimination targets requires health system interventions to enhance the care cascade

BACKGROUND

Modelling suggests that achieving the World Health Organization's elimination targets for hepatitis C virus (HCV) is possible by scaling up use of direct-acting antiviral (DAA) therapy. However, poor linkage to health services and retention in care presents a major barrier, in particular among people who inject drugs (PWID). We identify and assess the cost-effectiveness of additional health system interventions required to achieve HCV elimination targets in Australia, a setting where all people living with HCV have access to DAA therapy.

METHODS

We used a dynamic HCV transmission and liver-disease progression mathematical model among current and former PWID, capturing testing, treatment and other features of the care cascade. Interventions tested were: availability of point-of-care RNA testing; increased testing of PWID; using biomarkers in place of liver stiffness measurement; and scaling up primary care treatment delivery.

RESULTS

The projected treatment uptake in Australia reduced the number of people living with HCV from approximately 230,000 in 2015 to approximately 24,000 by 2030 and reduced incidence by 45%. However, the majority (74%) of remaining infections were undiagnosed and among PWID. Scaling up primary care treatment delivery and using biomarkers in place of liver stiffness measurement only reduced incidence by a further 1% but saved AU$32 million by 2030, with no change to health outcomes. Additionally replacing HCV antibody testing with point-of-care RNA testing increased healthcare cost savings to AU$62 million, increased incidence reduction to 64% and gained 11,000 quality-adjusted life years, but critically, additional screening of PWID was required to achieve HCV elimination targets.

CONCLUSION

Even with unlimited and unrestricted access to HCV DAA treatment, interventions to improve the HCV cascade of care and target PWID will be required to achieve elimination targets.

"I feel like I've hit the bottom and have no idea what to do": Supportive social networking on Reddit for individuals with a desire to quit cannabis use

BACKGROUND

Online communities can provide social support to those in need and can foster personal empowerment for individuals experiencing distress. This study examines the content of a Reddit community dedicated to the support of people trying to quit using cannabis, in order to develop an understanding of the type of social networking occurring on this subreddit (e.g., community).

METHODS

A total of 100 Reddit posts and their replies (i.e., comments) were collected from the subreddit on June 12, 2015. Posts were qualitatively coded for expression of DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) symptoms of cannabis use disorder (CUD) as well as other prominently featured themes. Comments on posts where individuals were seeking support/advice were also coded.

RESULTS

Ninety-one people posted the 100 Reddit posts, and of those 35 (38%) people described enough symptoms to be classified as mild disorder severity, 15 (16%) moderate, and 11 (12%) severe, as outlined in the diagnostic criteria for CUD. Over half of posts (n = 51) were seeking advice and/or support from members of the community. There were 174 comments made by 108 unique people on the advice/support seeking posts. Most were supportive/encouraging in nature (140, 80%) and gave advice to the post author (126, 72%).

CONCLUSIONS

This exploratory research highlights the potential of online communities as tools for individuals coping with addiction recovery, and future research should investigate if involvement in such communities would be a beneficial supplement to more traditional recovery practices.

Correlates of three-year outpatient medical care use among rural stimulant users

Outpatient medical care (OMC) settings are a care context in which effective management of unhealthy substance use can occur. However, no studies have documented rates of OMC use and characteristics of OMC use among rural substance users. This study sought to examine the rates and frequency of OMC use in a sample of rural drug users over a three-year period. We also explored characteristics of participants associated with use of OMCs over time. Data were collected from June 2005 to September 2007 from a natural history study of 710 stimulant users living in rural communities. Participants were adults, not in drug treatment, and reporting recent methamphetamine, crack cocaine or powder cocaine use. Between 34 and 39% of participants reported any use of an OMC over the three-year follow-up period, with a mean average number of visits ranging from one to two at each follow-up. Having medical insurance, reporting any use of substance use disorder-related care (including formal substance use treatment or mutual-help groups), and higher Addiction Severity Index (ASI) medical and psychiatric composite scores were associated with greater odds of any OMC use and higher frequency of OMC use over time. Being male and having higher ASI alcohol and drug composite scores were associated with lower odds of any OMC use and lower frequency of OMC use. Our findings support the importance of public health efforts to increase OMC use among male rural drug users and those with more severe drug and alcohol use, the important role(s) of Federally Qualified Health Centers and other OMCs in rural communities that serve those with low rates of health insurance, and the need for public health efforts to increase the use of OMCs among rural drug users not experiencing more severe medical or psychiatric health problems.

Associations Between Religiosity, Perceived Social Support, and Stimulant Use in an Untreated Rural Sample in the U.S.A

BACKGROUND

Religiosity and perceived social support (SS) may serve as protective factors for more severe substance use in adults.

OBJECTIVES

This study sought to examine whether aspects of religiosity and SS are associated with longitudinal reductions in stimulant use over three years in an untreated sample of rural drug users.

METHODS

Respondent-driven sampling was used to recruit stimulant users (N = 710) from Arkansas, Kentucky, and Ohio. Follow-up interviews were conducted at 6-month intervals for 36 months.

RESULTS

Our bivariate findings indicate that higher religiosity was associated with lower odds and fewer days of methamphetamine and cocaine use. After controlling for covariates, higher religiosity was associated with fewer days of crack cocaine use, but more days of methamphetamine use among a small sample of users in the two final interviews. Higher SS from drug-users was also associated with higher odds and days of methamphetamine and powder cocaine use, while higher SS from nondrug users was associated with fewer days of methamphetamine use.

CONCLUSIONS/IMPORTANCE

Our bivariate findings suggest that higher levels of religiosity may be helpful for some rural individuals in reducing their drug use over time. However, our multivariate findings suggest a need for further exploration of the potential effects of religiosity on longer-term drug use, especially among those who continue to use methamphetamine and/or remain untreated. Our findings also highlight the potential deleterious effect of SS from drug users on the likelihood and frequency of methamphetamine and powder cocaine use over time among untreated rural drug users.

Cost-effectiveness of treating chronic hepatitis C virus with direct-acting antivirals in people who inject drugs in Australia

BACKGROUND AND AIM

Reducing the burden of hepatitis C virus (HCV) related liver disease will require treating people who inject drugs (PWID), the group at most risk of infection and transmission. We determine the cost-effectiveness of treating PWID with interferon-free direct-acting antiviral therapy in Australia.

METHODS

Using a deterministic model of HCV treatment and liver disease progression, including a fixed rate of re-infection, the expected healthcare costs and quality-adjusted life years (QALYs) of a cohort of newly HCV-infected PWID were calculated for: no treatment; treatment after initial infection ("early-treatment"); and treatment prior to developing compensated cirrhosis ("late-treatment"). Incremental cost-effectiveness ratios (ICERs) were used to compare scenarios.

RESULTS

Late-treatment was cost-effective compared to no treatment, with a discounted average gain of 2.98 (95%confidence interval 2.88-5.22) QALYs per person for an additional cost of $15,132 ($11,246-18,922), giving an ICER of $5078 ($2847-5295) per QALY gained. Compared to late-treatment, early-treatment gained a further discounted average of 2.27 (0.58-4.80) QALYs per person for $38,794 ($34,789-41,367), giving an ICER of $17,090 ($2847-63,282), which was cost-effective in approximately 90% of Monte-Carlo uncertainty simulations. For every 100 newly HCV-infected PWID, there were an estimated 40 (39-56) eventual liver-related deaths without treatment, compared to 7 (6-11) and 8 (7-13) with early-treatment and late-treatment available respectively.

CONCLUSIONS

Treating HCV-infected PWID with new therapies is cost-effective and could prevent a significant number of liver-related deaths. Although late-treatment was the most cost-effective option, the cost per QALY gained for early-treatment compared to late-treatment is likely to be below unofficial Australian willingness to pay thresholds.

The CHANGE Study: Methods and Sample Description for a Cross-Sectional Study of Heroin Cessation in New York City

The CHANGE (Cessation of Heroin: A Neighborhood Grounded Exploration) Study aimed to understand factors associated with the initiation and maintenance of sustained heroin cessation from the perspective of users themselves and specifically set out to document the correlates of natural recovery. The CHANGE Study was a case-control study conducted in New York City from 2009 to 2011. Cases were former heroin users, abstinent for 1-5 years in the past 5 years. Controls used heroin at least weekly during the past 5 years and were (1) continuous heroin users without a quit attempt of ≥2 weeks' duration or (2) relapsed heroin users who were currently using and had a quit attempt of ≥2 weeks' duration during the past 5 years. Recruitment and data collection methods are described along with limitations and a brief description of the study sample. In contrast to many studies of drug use and cessation, the CHANGE Study was designed to model success (i.e., initiation and maintenance of heroin cessation) and not failure.

Systematic analysis of changes in cannabis use among participants in control conditions of randomised controlled trials

Introduction

Cannabis remains the most used illegal substance across the globe, and negative outcomes and disorders are common. A spotlight therefore falls on reductions in cannabis use in people with cannabis use disorder. Current estimates of unassisted cessation or reduction in cannabis use rely on community surveys, and few studies focus on individuals with disorder. A key interest of services and researchers is to estimate effect size of reductions in consumption among treatment seekers who do not obtain treatment. Effects within waiting list or information-only control conditions of randomised controlled trials offer an opportunity to study this question.

Method

This paper examines the extent of reductions in days of cannabis use in the control groups of randomised controlled trials on treatment of cannabis use disorders. A systematic literature search was performed to identify trials that reported days of cannabis use in the previous 30 (or equivalent).

Results

Since all but one of the eight identified studies had delayed treatment controls, results could only be summarised across 2-4 months. Average weighted days of use in the previous 30 days fell from 24.5 to 19.9, and a meta-analysis using a random effects model showed an average reduction of 0.442 SD. However, every study had at least one significant methodological issue.

Conclusions

While further high-quality data is needed to confirm the observed effects, these results provide a baseline from which researchers and practitioners can estimate the extent of change required to detect effects of cannabis treatments in services or treatment trials.

Long-term course of opioid addiction

Opioid addiction is associated with excess mortality, morbidities, and other adverse conditions. Guided by a life-course framework, we review the literature on the long-term course of opioid addiction in terms of use trajectories, transitions, and turning points, as well as other factors that facilitate recovery from addiction. Most long-term follow-up studies are based on heroin addicts recruited from treatment settings (mostly methadone maintenance treatment), many of whom are referred by the criminal justice system. Cumulative evidence indicates that opioid addiction is a chronic disorder with frequent relapses. Longer treatment retention is associated with a greater likelihood of abstinence, whereas incarceration is negatively related to subsequent abstinence. Over the long term, the mortality rate of opioid addicts (overdose being the most common cause) is about 6 to 20 times greater than that of the general population; among those who remain alive, the prevalence of stable abstinence from opioid use is low (less than 30% after 10-30 years of observation), and many continue to use alcohol and other drugs after ceasing to use opioids. Histories of sexual or physical abuse and comorbid mental disorders are associated with the persistence of opioid use, whereas family and social support, as well as employment, facilitates recovery. Maintaining opioid abstinence for at least five years substantially increases the likelihood of future stable abstinence. Recent advances in pharmacological treatment options (buprenorphine and naltrexone) include depot formulations offering longer duration of medication; their impact on the long-term course of opioid addiction remains to be assessed.

Gender differences in substance abuse treatment and barriers to care among persons with substance use disorders with and without comorbid major depression

OBJECTIVES

To compare substance use disorders (SUD) treatment patterns and barriers to such treatment among men and women with SUD with and without comorbid major depressive episodes (MDE) in a community sample.

METHODS

Using data from adult participants in the National Survey on Drug Use and Health 2005-2010, we investigated differences by sex in the association of MDE comorbidity with SUD on patterns of, perceived unmet need for, and the perceived barriers to SUD treatments.

RESULTS

Compared with participants with SUD without MDE, both men and women with comorbid SUD and MDE were more likely to use SUD services or to report an unmet need for such treatment. Sex modified the association of comorbidity and treatment patterns: males with MDE comorbidity had a greater likelihood of emergency room visits and use of inpatient services than females. Barriers to substance treatment were remarkably similar for males and females in both the SUD without MDE group and with MDE group, with attitudinal factors being the most common barriers.

CONCLUSIONS

Comorbidity with MDE seems to be an important predictor of service utilization and perceived need for SUD treatment in both men and women. The association of comorbidity with the use of some types of services, however, seems to vary according to sex. The findings have implications for the design of sex-specific SUD treatment programs.

Drug use disorders and post-traumatic stress disorder over 25 adult years: role of psychopathology in relational networks

BACKGROUND

In traumatized populations, drug use disorders and post-traumatic stress disorder (PTSD) persist for many years. Relational factors that mediate this persistence have rarely been systematically examined. Our aim is to examine the relative effects of psychopathology in familial and non-familial networks on the persistence of both disorders over adulthood.

METHODS

We utilized longitudinal data from an epidemiologically ascertained sample of male Vietnam veterans (n=642). Measures included DSM-IV drug use disorders, other psychiatric disorders, network problem history and time-varying marital and employment characteristics. Longitudinal measures of veterans' psychopathology and social functioning were retrospectively obtained for each year over a 25 year period. We used generalized estimating equations (GEE) to estimate the relative effects of network problems on veteran's drug use disorders and PTSD after adjusting for covariates.

RESULTS

Veterans' mean age was 47 years in 1996. Prevalence of illicit drug disorders declined from 29.8% in 1972 to 8.3% in 1996, but PTSD remained at 11.7% from 13.2% in 1972. While 17.0% of veterans reported a familial drug use problem, 24.9% reported a non-familial drug use problem. In full GEE models, a non-familial drug problem was a significant predictor of illicit drug use disorders over 25 years (OR=2.21, CI=1.59-3.09), while both familial depression (OR=1.69, CI=1.07-2.68) and non-familial drinking problem (OR=1.66, CI=1.08-2.54) were significant predictors of PTSD over 25 years.

CONCLUSIONS

Familial and non-familial problems in networks differentially affect the persistence of drug use disorders and PTSD in traumatized male adults.

Probability and predictors of cannabis use disorders relapse: results of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC)

BACKGROUND

This study aims to estimate the odds and predictors of Cannabis Use Disorders (CUD) relapse among individuals in remission.

METHODS

Analyses were done on the subsample of individuals with lifetime history of a CUD (abuse or dependence) who were in full remission at baseline (Wave 1) of the National Epidemiological Survey of Alcohol and Related Conditions (NESARC) (n=2350). Univariate logistic regression models and hierarchical logistic regression model were implemented to estimate odds of relapse and identify predictors of relapse at 3 years follow up (Wave 2).

RESULTS

The relapse rate of CUD was 6.63% over an average of 3.6 year follow-up period. In the multivariable model, the odds of relapse were inversely related to time in remission, whereas having a history of conduct disorder or a major depressive disorder after Wave 1 increased the risk of relapse.

CONCLUSIONS

Our findings suggest that maintenance of remission is the most common outcome for individuals in remission from a CUD. Treatment approaches may improve rates of sustained remission of individuals with CUD and conduct disorder or major depressive disorder.

Motivations to quit cannabis use in an adult non-treatment sample: are they related to relapse?

BACKGROUND

The majority of cannabis smokers who quit do so without formal treatment, suggesting that motivations to quit are an important part of cessation process. However, little is known about how motivations relate to successful quitting.

METHOD

A convenience sample of 385 non-treatment-seeking adult cannabis smokers (58% male, age 16-64years at start of quit attempt) who made a "serious" (self-defined) quit attempt without formal treatment while not in a controlled environment were administered the 176-item Marijuana Quit Questionnaire (MJQQ) to assess their motivations to quit and outcome of the quit attempt. Exploratory factor analysis was performed to identify significant motivational factors. Subgroup comparisons used t-tests and ANOVA. Cox proportional hazard regression and the General Linear Model were performed to evaluate the influence of motivational factors, gender, and age on relapse status at time of interview and risk of relapse over time, with time between quit attempt and interview as a covariate.

RESULTS

Exploratory factor analysis identified 6 motivational factors with eigenvalues >1 which accounted for 58.4% of the total variance: self-image and self-control, health concerns, interpersonal relationship concerns, legal concerns, social acceptability concerns, and self-efficacy. Women were more likely than men to be motivated by self-image/self-control, health concerns, and social acceptability concerns. Older individuals were more likely to be motivated by health concerns. At the time of interview, 339 subjects had relapsed. Self-image and self-control, health concerns, interpersonal relationship concerns, and social acceptability concerns were associated with greater likelihood of abstinence at the study interview. Legal concerns and social acceptability concerns were associated with significantly lower hazard ratios (0.88, 0.83) for relapse during the abstinent period.

CONCLUSION

These findings show gender and age differences in motivations to quit cannabis smoking and that adult cannabis smokers have motivations to quite similar to those of adolescent cannabis smokers and of adults who quit alcohol and tobacco use without formal treatment. The findings suggest areas of focus to improve secondary prevention and psychosocial treatment efforts.

Efficacy of buspirone for attenuating cocaine and methamphetamine reinstatement in rats

BACKGROUND

There are no approved pharmacotherapies for preventing psychomotor stimulant relapse. The operant reinstatement model has been suggested as a screen for identifying candidate medications. The present study examined if the anxiolytic buspirone could attenuate reinstatement of extinguished responding in Long-Evans rats that previously self-administered intravenous cocaine or methamphetamine.

METHODS

Rats were trained in 2-h daily sessions to self-administer 0.5mg/kg cocaine or 0.1mg/kg methamphetamine infusions followed by 12 days of instrumental extinction. Reinstatement was evoked by 17mg/kg i.p. cocaine primes or response-contingent cocaine-paired cues in cocaine-reinforced rats, and by 1mg/kg i.p. methamphetamine primes or response-contingent methamphetamine-paired cues in methamphetamine-reinforced rats.

RESULTS

Buspirone (1 and 3mg/kg) significantly (p<0.05) attenuated cocaine cue but not cocaine prime reinstatement. Buspirone (1 and 3mg/kg) also significantly attenuated methamphetamine cue reinstatement. Buspirone (3mg/kg) significantly attenuated methamphetamine prime reinstatement. During all reinstatement tests, 3mg/kg buspirone reduced levels of inactive lever pressing relative to those of vehicle, significantly so during the cocaine cue-induced reinstatement tests.

CONCLUSIONS

Given the complexity of buspirone's neuropharmacology consisting of serotonin 5-HT1A receptor partial agonist activity, and dopamine D2, D3 and D4 receptor antagonist effects, it is uncertain which of these activities or their combination is responsible for the present results. Overall, these results suggest that buspirone may reduce the likelihood of relapse to cocaine and methamphetamine use under some conditions, although this speculation must be interpreted with caution given buspirone's similar potency to attenuate inactive-lever responding.

Assessing the cost-effectiveness of treating chronic hepatitis C virus in people who inject drugs in Australia

BACKGROUND AND AIM

To assess the cost-effectiveness of hepatitis C virus treatment with pegylated interferon alfa-2a and ribavirin in current and former people who inject drugs (PWID).

METHODS

A decision analytic model simulated the lifetime costs and outcomes of four treatment options: early treatment with mild fibrosis, standard treatment with moderate fibrosis, late treatment with compensated cirrhosis, and no treatment. Treatment modalities were simulated across current, former, and never-injector cohorts of 1000 hypothetical patients with chronic hepatitis C virus. The main outcome measures were incremental costs ($AUD) per quality-adjusted life years (QALYs) gained, and incremental cost-effectiveness ratios (ICERs) were calculated for each cohort.

RESULTS

Treatment of current PWID during mild fibrosis resulted in a discounted average gain of 1.60 QALYs (95% confidence interval 0.93-2.26) for an added cost of $12,723 ($11,153-$14,396) compared with no treatment, yielding an ICER of $7941 per QALY gained ($6347-$12,017). Former PWID gained 1.80 QALYs (1.29-2.33) for $10,441 ($8843-$12,074) for early treatment compared with no treatment, resulting in an ICER of $5808 per QALY gained ($5189-$6849). Never-injectors gained 2.33 QALYs (1.87-2.80) for $9290 ($7642-$10,912) compared with no treatment-an ICER of $3985 per QALY gained ($3896-$4080). Early treatment was more cost-effective than late treatment in all cohorts.

CONCLUSIONS

Despite comorbidities, increased mortality, and reduced adherence, treatment of both current and former PWID is cost-effective. Our estimates fall below the unofficial Australian cost-effectiveness threshold of $AUD 50,000 per QALY for public subsidies. Scaling up treatment for PWID can be justified on purely economic grounds.

Relapse Prevention: A Critique and Proposed Reconceptualisation

Relapse prevention (RP) plays a significant role in current treatments and post-treatment approaches to substance abuse problems. It is also widely used in a number of other problem areas, including other addictive behaviours and sexual offending. The widespread use of RP in various fields is due to both its clearly articulated theoretical basis, which has significant face validity, and its transferability into clinical practice. Also, there is a growing (though arguably still modest) body of empirical evidence that demonstrates its efficacy in a range of therapeutic contexts. However, arguably, in terms of both the theoretical underpinnings and the practical application of RP there is room for improvement. This article hypothesises that one of the key weaknesses of RP is that it takes a generally unconstructive approach to the therapeutic process through the use of negative concepts and avoidance goals. It is suggested that a ‘good lives’ framework of psychological wellbeing can provide a means of remedying these weaknesses of the traditional RP model. It is argued that a good lives framework can lead to a more optimistic approach to the prevention of relapse among individuals with substance use problems.

Trajectories of injection drug use over 20 years (1988-2008) in Baltimore, Maryland

The objective of this study was to identify longitudinal patterns of injection drug use over 20 years in the AIDS Linked to the Intravenous Experience (ALIVE) Study, a community-based cohort of injection drug users (IDUs) in Baltimore, Maryland, with a focus on injection cessation. Starting in 1988, persons over 18 years of age with a history of injection drug use were recruited into the study. Participants provided information on their injection drug use semiannually through 2008. The analysis was restricted to 1,716 IDUs with at least 8 study visits. Finite mixture models were used to identify trajectories and predictors of injection patterns over time. The mean age of participants was 35 years; 75% were male, and 95% were African-American. Five distinct patterns were identified: 2 usage patterns (32% engaged in persistent injection and 16% had frequent relapse) and 3 cessation patterns (early cessation (19%), delayed cessation (16%), and late cessation (18%)). A history of drug treatment, no recent use of multiple substances, and less frequent injection distinguished the early cessation group from the other groups. This study demonstrated multiple trajectories of drug injection behaviors, with a substantial proportion of IDUs stopping injection over extended time frames. For maximum effectiveness, public health programs for IDUs should be long-term, comprehensive, and targeted toward individual patterns of use.

Probability and predictors of remission from life-time nicotine, alcohol, cannabis or cocaine dependence: results from the National Epidemiologic Survey on Alcohol and Related Conditions

AIM

To estimate the general and racial/ethnic specific cumulative probability of remission from nicotine alcohol cannabis or cocaine dependence, and to identify predictors of remission across substances.

DESIGN

Data were collected from structured diagnostic interviews using the Alcohol Use Disorder and Associated Disabilities Interview Schedule-DSM-IV version.

SETTING

The 2001-2002 National Epidemiological Survey of Alcohol and Related Conditions (NESARC) surveyed a nationally representative sample from US adults (n = 43,093) selected in a three-stage sampling design.

PARTICIPANTS

The subsamples of individuals with life-time DSM-IV diagnosis of dependence on nicotine (n = 6937), alcohol (n = 4781), cannabis (n = 530) and cocaine (n = 408).

MEASUREMENTS

Cumulative probability estimates of dependence remission for the general population and across racial/ethnic groups. Hazard ratios for remission from dependence.

FINDINGS

Life-time cumulative probability estimates of dependence remission were 83.7% for nicotine, 90.6% for alcohol, 97.2% for cannabis and 99.2% for cocaine. Half of the cases of nicotine, alcohol, cannabis and cocaine dependence remitted approximately 26, 14, 6 and 5 years after dependence onset, respectively. Males, Blacks and individuals with diagnosis of personality disorders and history of substance use comorbidity exhibited lower hazards of remission for at least two substances.

CONCLUSIONS

A significant proportion of individuals with dependence on nicotine, alcohol, cannabis or cocaine achieve remission at some point in their life-time, although the probability and time to remission varies by substance and racial/ethnic group. Several predictors of remission are shared by at least two substances, suggesting that the processes of remission overlap. The lower rates of remission of individuals with comorbid personality or substance use disorders highlight the need for providing coordinated psychiatric and substance abuse interventions.

Course of alcohol dependence among Vietnam combat veterans and nonveteran controls

OBJECTIVE

Identifying developmental trajectories of alcohol use is fundamental in building theories of alcoholism etiology and course. The purpose of this study was to replicate and generalize our previous finding that had been based on a twin sample drawn from the Vietnam Era Twin Registry. In this study, we made use of a nontwin sample of Vietnam veterans drawn from the Vietnam Era Study--a 25-year follow-up of the Vietnam Drug User Returns project that assessed the long-term medical and psychiatric consequences of substance abuse or dependence in Vietnam.

METHOD

Alcohol-related behaviors and psychiatric status were assessed in a sample of 839 individuals that comprised 323 veterans who tested positive for drugs (i.e., opiates, barbiturates, or amphetamines) on discharge from Vietnam, 319 veterans who tested negative for drugs at that time, and a nonveteran control sample (n = 197). Individuals with a lifetime diagnosis of alcohol dependence (n = 293) were selected for further analysis. Using detailed life history charts, in-person structured interviews were conducted, which entailed retrospective reports covering the 25 years since the 1972 survey. Measures of alcohol and drug use as well as psychiatric symptoms were obtained by assessing each year of the follow-up interval, beginning with 1972.

RESULTS

Using latent growth mixture modeling, a four-class model was identified with trajectories that were parallel to those identified in our previous studies based on the Vietnam Era Twin Registry: severe chronic alcoholics, severe nonchronic alcoholics, late-onset alcoholics, and young-adult alcoholics.

CONCLUSIONS

Present findings provide additional support for the replicability and generalizability of meaningful differences in the course of alcoholism from early adulthood to midlife.

Longitudinal relationship between psychological distress and multiple substance use: results from a three-year multisite natural-history study of rural stimulant users

OBJECTIVE

Substance use is associated with poor mental health, but little is known regarding how use of multiple substances is associated with mental health, particularly longitudinally, in community studies. This article examines this issue in a large (N = 710), natural-history study of rural stimulant (cocaine and/or methamphetamine) users in three states.

METHOD

Respondent-driven sampling recruited recent (past-30-day) stimulant users in three counties each in Arkansas, Kentucky, and Ohio. Participants were interviewed every 6 months for 3 years. Mental health was measured by the Brief Symptom Inventory, and prior 6 months' substance use was measured for 17 possible substances. Data analysis used generalized estimating equations for longitudinal data with the Global Severity Index of the Brief Symptom Inventory as the dependent variable at each interview and substance use as predictor variables measured by number of substances used in the past 6 months and, separately, the 17 individual substances, adjusting for use of substance-use treatment, demographics, and recruitment site.

RESULTS

On average, both Global Severity Index score and use of many substances declined over the course of study. Global Severity Index score was significantly associated with (a) greater number of substances used in the past 6 months (p < .0001) and (b) use of crack cocaine, methamphetamine, and nonprescription use of prescription painkillers and tranquilizers.

CONCLUSIONS

Multiple and specific substances appear to incrementally increase psychological distress. Users of cocaine and methamphetamine are present in rural areas; these associations with poor psychological health raise concerns regarding availability of local treatment services for individuals with mental-health problems, as well as substance abuse.

A systematic review of post-deployment injury-related mortality among military personnel deployed to conflict zones

BACKGROUND

This paper reports on a systematic review of the literature on the post-conflict injury-related mortality of service members who deployed to conflict zones.

METHODS

Literature databases, reference lists of articles, agencies, investigators, and other sources were examined to find studies comparing injury-related mortality of military veterans who had served in conflict zones with that of contemporary veterans who had not served in conflict zones. Injury-related mortality was defined as a cause of death indicated by International Classification of Diseases E-codes E800 to E999 (external causes) or subgroupings within this range of codes.

RESULTS

Twenty studies met the review criteria; all involved veterans serving during either the Vietnam or Persian Gulf conflict. Meta-analysis indicated that, compared with non-conflict-zone veterans, injury-related mortality was elevated for veterans serving in Vietnam (summary mortality rate ratio (SMRR) = 1.26, 95% confidence interval (95%CI) = 1.08-1.46) during 9 to 18 years of follow-up. Similarly, injury-related mortality was elevated for veterans serving in the Persian Gulf War (SMRR = 1.26, 95%CI = 1.16-1.37) during 3 to 8 years of follow-up. Much of the excess mortality among conflict-zone veterans was associated with motor vehicle events. The excess mortality decreased over time. Hypotheses to account for the excess mortality in conflict-zone veterans included post-traumatic stress, coping behaviors such as substance abuse, ill-defined diseases and symptoms, lower survivability in injury events due to conflict-zone comorbidities, altered perceptions of risk, and/or selection processes leading to the deployment of individuals who were risk-takers.

CONCLUSION

Further research on the etiology of the excess mortality in conflict-zone veterans is warranted to develop appropriate interventions.

Comparing the dynamic course of heroin, cocaine, and methamphetamine use over 10 years

To examine dynamic changes in drug-use trajectories over time we analyzed episode types and predictors of quitting use over the 10 years following drug-use initiation for 1797 heroin, cocaine, and methamphetamine (meth) users. Most episodes reflected high use and incarceration, however these events occurred more frequently among heroin and meth users. Quitting was predicted by current treatment and self-help participation among meth (RR 2.57, 1.79-3.70; 2.57, 1.80-3.67) and cocaine (RR 2.00, 1.42-2.81; 2.10, 1.63-2.72) users, and by a history of quitting for meth users (RR 1.11, 1.06-1.17). Quitting was less likely among all users under legal supervision (RR 0.55-0.69) and among heroin (RR 0.66, 0.45-0.97) and meth users (RR 0.73, 0.60-0.89) with an early drug-use onset. Relative to cocaine or meth use, heroin use was characterized by persistent use at a high-level which was often only interrupted by incarceration. While quitting drug use can be facilitated by treatment and/or self-help participation, few people had these experiences in the 10 years following first use.

Using administrative data for longitudinal substance abuse research

The utilization of administrative data in substance abuse research has become more widespread than ever. This selective review synthesizes recent extant research from 31 articles to consider what has been learned from using administrative data to conduct longitudinal substance abuse research in four overlapping areas: (1) service access and utilization, (2) underrepresented populations, (3) treatment outcomes, and (4) cost analysis. Despite several notable limitations, administrative data contribute valuable information, particularly in the investigation of service system interactions and outcomes among substance abusers as they unfold and influence each other over the long term. This critical assessment of the advantages and disadvantages of using existing administrative data within a longitudinal framework should stimulate innovative thinking regarding future applications of administrative data for longitudinal substance abuse research purposes.

The life course perspective on drug use: a conceptual framework for understanding drug use trajectories

This article discusses the life course perspective on drug use, including conceptual and analytic issues involved in developing the life course framework to explain how drug use trajectories develop during an individual's lifetime and how this knowledge can guide new research and approaches to management of drug dependence. Central concepts include trajectories marked by transitions and social capital and turning points influencing changes. The life course perspective offers an organizing framework for classifying varying drug use trajectories, identifying critical events and factors contributing to the persistence or change in drug use, analytically ordering events that occur during the life span, and determining contributory relationships.

The legitimacy of addiction treatment in a world of smart people

AIM

This paper discusses what type of legitimacy underpins addiction treatment in contemporary western societies.

METHOD

Broad review of the relevant literature.

CONCLUSIONS

The legitimacy of professional interventions and the future of service provision will depend largely on the relationship between the professional and the lay referral system. These in turn are intertwined with macro-societal changes. The basic categories in this relationship are, on one hand, the idea of evidence-based practice (i.e. the notion of using the most accurate scientific support for the choice of treatment interventions), and on the other hand the consumer perspective, which conceptualizes addiction treatment as an interactive process between the treatment provider and the consumer. The acceptance of addiction treatment depends in most cases on the client who chooses from a whole range of informal and formal problem solutions. To an extent, experts are thus controlled by their lay counterparts and need their consent to operate and succeed. This process is complicated by the trend towards evidence-based practice, which demands transparency and rigorous procedures and carries with it the basis for distrust in expert knowledge by displaying openly that every statement of fact is open to revision, and thus, to a certain extent, characterized by uncertainty.

Self-change: A pathway to cannabis abuse resolution

Long-term daily cannabis abusers (N = 25) who without treatment stopped using cannabis for at least one year were interviewed about their past substance use, antecedents to change, and factors supportive of change. Respondents' cannabis problems decreased in the year prior to their recovery compared to their lifetime use. Respondents described their successful quit attempts through structured interviews and autobiographical narratives. The narratives were content analyzed for factors related to recovery. The reports indicated that marijuana cessation was motivated more by internal than external factors, and the most common precipitants of quit attempts were cognitive anti-cannabis factors. The major reason reported by respondents for stopping cannabis was a change in how they viewed their cannabis use, followed by negative personal effects. The most common reported maintenance factors were avoidance of situations in which cannabis was used, changes in lifestyle, and the development of non-cannabis-related interests. Cognitive and respiratory functioning were also assessed. Lastly, more than 75% of respondents reported not seeking treatment because they believed it was not needed or because they wanted to quit on their own. Directions for future research are offered.

Heroin dependence in an English town: 33-year follow-up

BACKGROUND

There has been no long-term study of people addicted to injected heroin who have been treated without the prescribing of substitute opioids.

AIMS

To investigate the outcome for patients treated for injected heroin addiction 33 years after they were first seen, and 26 years after they were first followed up, in terms of sustained abstinence, continuing maintenance on methadone and deaths.

METHOD

Eighty-six people with heroin addiction first seen in in 1966-1967 in a small town in the south-east of England were located and their clinical state assessed using multiple sources, including personal interviews with a proportion of the cohort.

RESULTS

Forty-two per cent of the cohort had been abstinent for at least 10 years; 10% were taking methadone and were classified as addicted; and 22% had died. Eight percent of the cohort could not be located.

CONCLUSIONS

Results proved favourable in the above three parameters compared with other long-term studies.

Gender differences in long-term drug treatment outcomes in Chicago PETS

Few long-term follow-up studies of substance abusers have examined gender differences. In the current study, gender differences were examined at 36 months following residential or outpatient drug-free treatment among 951 participants in the Chicago Target Cities Project, the majority of whom were female (62%) and African American (93%). There were no differences in the proportion of men and women who reported any alcohol or drug use at the 36-month follow-up, with an overall reduction of 41% from intake. Greater proportions of men were incarcerated or employed, whereas greater proportions of women had returned to treatment, lived with their children, lived with a substance user, or had interpersonal problems. Women, as a group, had greater increases over time in self-help participation, free time spent with family, non-using family/friends, and employment. Although both men and women showed significant improvements following treatment, gender differences persisted in several areas of psychosocial functioning related to recovery.

Post-traumatic stress disorder, drug dependence, and suicidality among male Vietnam veterans with a history of heavy drug use

This study examines the roles of post-traumatic stress disorder (PTSD) and drug dependence in non-fatal suicidality, i.e., suicidal ideation and suicide attempt, among Vietnam veterans in their adult years. The sample includes male veterans deployed to Vietnam, including an oversample of those who tested positive for opiates at their return (n = 642). PTSD, substance abuse, suicidality, and other psychopathology are analyzed using three waves of survey and military data covering the time period from early adolescence to middle adulthood. Measures include the onset and recency of each of the lifetime DSM-IV PTSD symptom criteria, and yearly symptom measures of DSM-IV dependence for alcohol and eight classes of psychoactive substances. Survival and hazard models are applied to assess the effects of drug dependence, PTSD, and other psychopathology on the duration of suicidality. Longitudinal models estimate the casual relationships among PTSD, drug dependence, and suicidality over a 25-year period. Results show evidence of strong continuity of PTSD, drug dependence, and suicidality over time. The causal role of drug dependence on PTSD and suicidality is limited to young adulthood. Evidence is stronger for self-medication in later adulthood. The results indicate that a life course perspective is needed for the combined treatment of PTSD and drug dependence for severely traumatized populations.

Determinants of Health Care Use among Puerto Rican Drug Users in Puerto Rico and New York City

This study was conducted to identify factors accounting for differences in health care and drug treatment utilization between Puerto Rican drug users residing in 2 separate locations. Survey findings from 334 drug users in Puerto Rico and 617 in New York City showed that those in Puerto Rico were 6 times less likely than their counterparts in New York to have used inpatient medical services and 13 to 14 times less likely to have used outpatient medical services or methadone. They also were less likely to have health insurance or past drug treatment. After site was controlled for, health insurance and previous use of physical or mental health services remained significant predictors of health care and drug treatment utilization during the study period. Although Puerto Rican drug users in Puerto Rico are not an ethnic minority, they reported significant disparities in health services use compared with Puerto Rican drug users in New York.