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.     

Cross-system data linkage for treatment outcome evaluation: lessons learned from the California Treatment Outcome Project

Using administrative data to evaluate health care outcomes has become increasingly common, but the reliability and validity of outcome measures based on cross-system data linkage have been little scrutinized. Applying a deterministic data matching methodology, we linked 6545 Californians admitted to 43 substance abuse treatment programs between 2000 and 2001 to administrative data acquired from three state agency databases. We compared self-reported treatment outcome measures to equivalent measures derived from official records on motor vehicle driving incidents, criminal history, and mental health services utilization. Administrative data provided analogous results in some measures (e.g., percent of people using mental health services, percent ever arrested) and more accurate results in others (e.g., frequency of service utilization, and frequency of arrests). Similar to findings based on the interview data, the administrative data also revealed improvements in several domains 1-year post-treatment compared to 1-year pre-treatment. Experiences with data linkage procedures and strategies for enhancing record linkage accuracy are discussed. Findings illustrate the value of using administrative records for substance abuse treatment outcome evaluation, while highlighting areas for improvement for future cross-system data linkage efforts.     

Longitudinal HIV risk behavior among the Drug Abuse Treatment Outcome Studies (DATOS) adult sample

Longitudinal trajectories for HIV risk were examined over 5 years following treatment among 1,393 patients who participated in the nationwide Drug Abuse Treatment Outcome Studies. Both injection drug use and sexual risk behavior declined over time, with most of the decline occurring between intake and the first-year follow-up. However, results of the application of growth mixture models for both sets of trajectories indicated that a subgroup of individuals reverted to a high-risk behavior over time, with a higher level of risk at the 5-year follow-up than their original risk level at intake. Of clients who were engaged in regular injection drug use at intake, 76% continued to inject drug at a moderate-stable or increased rate during the 5-year follow-up.     

Predictors of short-term treatment outcomes among California's Proposition 36 participants

California's voter-initiated Proposition 36 offers non-violent drug offenders community-based treatment as an alternative to incarceration or probation without treatment. This article reports short-term treatment outcomes subsequent to this major shift in drug policy. Data are from 1104 individuals randomly selected from all Proposition 36 participants assessed for treatment in five California counties during 2004. The overall study sample was 30% female, 51% white, 18% Black, 24% Hispanic, and 7% other racial/ethnic groups. The mean+/-SD age was 37+/-10 years. Counties varied considerably in participant characteristics, treatment service intensity, treatment duration, urine testing, and employment and recidivism outcomes, but not in drug use at 3-month follow-up. Controlling for county, logistic regression analysis showed that drug abstinence was predicted by gender (female), employment at baseline (full or part-time), residential (vs. outpatient) stay, low psychiatric severity, frequent urine testing by treatment facility, and more days in treatment. Recidivism was predicted only by shorter treatment duration. Employment predictors included age (younger), gender (male), baseline employment, and lower psychiatric severity. The study findings support drug testing to monitor abstinence and highlight the need to address employment and psychiatric problems among Proposition 36 participants.     

Treating drug-abusing offenders. Initial findings from a five-county study on the impact of California's Proposition 36 on the treatment system and patient outcomes

Five counties (Kern, Riverside, Sacramento, San Diego, San Francisco) that demonstrate both variations and similarities in their implementation of Proposition 36 (e.g., treatment approaches, urine testing) and patient mix have been selected to participate in a study assessing how California's Proposition 36 is affecting the drug treatment system and patient outcomes. Except for San Francisco, treatment admissions increased during the first year of Proposition 36 implementation over the prior year (27% in Kern, 21% in Riverside, 17% in Sacramento, and 16% in San Diego), mostly in outpatient drug-free programs. Compared to non-Proposition 36 patients, Proposition 36 patients were more likely to be men, first-time admissions, treated in outpatient drug-free programs, employed full-time, and users of methamphetamine or marijuana. They were less likely to be treated in residential programs or methadone maintenance programs and fewer reported heroin use or injection drug use. Guided by the multilevel open systems framework, the study examines key issues of Proposition 36 that influence treatment systems and outcomes and empirically identifies "best practice" approaches in treating drug-abusing offenders.     

Trajectories of heroin addiction: growth mixture modeling results based on a 33-year follow-up study

This study investigates trajectories of heroin use and subsequent consequences in a sample of 471 male heroin addicts who were admitted to the California Civil Addict Program in 1964-1965 and followed over 33 years. Applying a two-part growth mixture modeling strategy to heroin use level during the first 16 years of the addiction careers since first heroin use, the authors identified three groups with distinctive profiles: stably high-level heroin users (n = 278), late decelerated users (n = 149), and early quitters (n = 44). Study findings empirically demonstrate the chronic nature of heroin addiction and subsequent adverse consequences including mortality, mental health, and employment.     

Client and program factors associated with dropout from court mandated drug treatment

To examine why court mandated offenders dropout of drug treatment and to compare their characteristics, treatment experiences, perceptions, and outcomes with treatment completers, we analyzed self-reported and administrative data on 542 dropouts (59%) and 384 completers (41%) assessed for Proposition 36 treatment by thirty sites in five California counties during 2004. At intake, dropouts had lengthier criminal histories, lower treatment motivation, more severe employment and psychiatric problems, and more were using drugs, especially heroin. Relatively fewer dropouts received residential treatment and their retention was much shorter. A similar proportion of dropouts received services as completers and the mean number of services received per day by dropouts was generally more, especially to address psychiatric problems, during the first three months of treatment. The most commonly offender-reported reasons for dropout included low treatment motivation (46.2%) and the difficulty of the Proposition 36 program (20.0%). Consequences for dropout included incarceration (25.3%) and permission to try treatment again (24.0%). Several factors predicting drug treatment dropout were identified. Both groups demonstrated improved functioning at one-year follow-up, but fewer dropouts had a successful outcome (34.5% vs. 59.1%) and their recidivism rate was significantly higher (62.9% vs. 28.9%) even after controlling for baseline differences. Understanding factors associated with drug treatment dropout can aid efforts to improve completion rates, outcomes, and overall effectiveness of California's Proposition 36 program. Findings may also aid a broader audience of researchers and policy analysts who are charged with designing and evaluating criminal-justice diversion programs for treating drug-addicted offenders.     

Patterns of Crime and Drug Use Trajectories in Relation to Treatment Initiation and 5-Year Outcomes: An Application of Growth Mixture Modeling Across Three Datasets

Drug abusers vary considerably in their drug use and criminal behavior over time, and these trajectories are likely to influence drug treatment participation and treatment outcomes. Drawing on longitudinal natural history data from three samples of adult male drug users, we identify four groups with distinctive drug use and crime trajectories over the 5 years prior to their first treatment episode. The groups' characteristics of initial treatment are compared. The trajectory groups are then included in Poisson growth curve models to predict drug use, incarceration, and employment over the 5 years following first treatment. Findings indicate that posttreatment drug use decreased and posttreatment employment increased. There was little change in posttreatment incarceration. Posttreatment trajectories for drug use, incarceration, and employment were significantly different across the four trajectory groups.