Martin Y. Iguchi

Reinforcing operants other than abstinence in drug abuse treatment: an effective alternative for reducing drug use.

This study examines the effectiveness of using vouchers to reinforce either the provision of urine samples testing negative for illicit drugs (UA group) or the completion of objective, individually defined, treatment-plan-related tasks (TP group). A third group was assigned to the clinics standard treatment (STD group). Participants were randomly assigned to groups after a 6-week baseline-stabilization period. Urine specimens were collected thrice weekly throughout the study. In the UA condition, participants earned

Cocaine use and HIV risk behavior in methadone maintenance patients

5 (U.S. dollars) in vouchers for each drug-free urine submitted. In the TP condition, participants earned up to

Natural classes of treatment response.

15 in vouchers per week for demonstrating completion of treatment plan tasks assigned by their counselors. Contingencies were in effect for 12 weeks, after which all participants received the clinics standard treatment. Urinalysis results indicate that the TP intervention was significantly more effective in reducing illicit drug use than either the UA or STD interventions. These effects were maintained with a trend toward continuing improvement for the TP groups even after contingencies were discontinued.

Stages and processes of change among polydrug users in methadone maintenance treatment

This study examined sexual and drug use behavior in 247 methadone maintenance patients, to explore the association of cocaine use with human immunodeficiency virus (HIV) risk behavior. In univariate analyses, cocaine use was positively associated with any drug injection, number of injections, and sexual intercourse without condoms. These relationships remained significant after controlling for other drug use and demographic factors. Heroin use also contributed to injection-related risk. We conclude that cocaine use represents a continued source of risk for exposure to HIV in this population, and that more aggressive efforts are warranted to reduce illicit drug use, particularly of heroin and cocaine, in methadone patients.

Decline in self-reported dysphoria after treatment entry in inner-city cocaine addicts.

This study examines an approach to identifying patterns of treatment response over time. Treatment response profiles are identified by cluster analyzing a repeated measure of patient performance collected at intervals during treatment. The procedure is demonstrated in Study 1 using monthly urinalysis results of 103 patients entering methadone maintenance treatment. The internal, external, and face validities of derived treatment response profiles are evaluated. A logistic regression model predicting treatment response is then constructed from intake variables found to correspond with the treatment response profiles. Study 2 replicates the procedures on an independent sample. Treatment response profiles facilitate the analysis of treatment response offering advantages over common measures of treatment outcome, such as performance at follow-up, change in performance from treatment entry to follow-up, or performance summed across treatment.

Stages and processes of change as predictors of drug use among methadone maintenance patients.

We applied the stages-of-change model of Prochaska and DiClemente to the problem of drug use among methadone maintenance patients to examine correlates of different stages of treatment readiness. The 276 subjects were divided into stage categories based on self-reported drug use and questionnaire responses regarding plans to discontinue unauthorized drug use in the future. Confirmatory factor analytic procedures validated four process scales derived from a 60-item questionnaire. Each stage was characterized by a profile of change-process scores largely consistent with predictions, though these scores did not distinguish stages as clearly as has been reported in previous research. Analysis of subject characteristics revealed that those in the Precontemplation stage reported significantly longer treatment tenures than subjects in any other stage besides Maintenance.

Coping strategies and continued drug use among methadone maintenance patients

This study examined self-reported dysphoria in 82 consecutive admissions to intensive outpatient treatment for cocaine abuse on whom data for the Beck scales for depression, anxiety, and hopelessness were available for intake and 4 subsequent weeks with no more than 1 missing data point. Mean scores on the Beck Depression Inventory (BDI) and the Beck Anxiety Inventory (BAI) decreased significantly between intake and Week 1, with no further significant changes from Weeks 1-4. Similar drops in the rate of clinically significant BDI and BAI scores also were observed. Scores on the Beck Hopelessness Scale (BHS) showed no significant changes. By Week 4, rates of clinically significant depression, anxiety, and hopelessness were similar (17%, 13%, and 16%, respectively). These findings suggest that assessing depression and anxiety using the BDI and BAI in this population should be postponed for at least 1 week after intake and that intake levels of self-reported mood may be inappropriate baseline measures for evaluating treatment effects.

Situations occasioning cocaine use and cocaine abstinence strategies

In this study the authors evaluated the predictive validity of stages-of-change and processes-of- change measures among methadone maintenance patients. One month after treatment entry, participants completed questionnaires providing stage and process scale scores regarding readiness to discontinue polydrug use. Participants also completed an algorithm assigning them to a stage category on the basis of their stated intentions regarding quitting. The algorithm predicted urinalysis results during a 12-week posttest period; however, only 1 stage scale (contemplation) and no process scales correlated significantly with outcome. In a hierarchical regression, stage and process scale scores significantly improved prediction of posttest abstinence beyond that afforded by baseline drug-free urine rates, but this effect was attributable to the contemplation scale alone. Despite their widespread use, stage and process scales have yet to demonstrate clearly predictive validity.

Change in Drug-Using Networks of Injecting Drug Users during Methadone Treatment: A Pilot Study Using Snowball Recruitment and Intensive Interviews

Drug addiction has been conceived as a maladaptive means of coping utilized by individuals unable or unwilling to deal with stresses in more adaptive ways. Although a growing body of evidence supports the link between alcohol abuse and maladaptive coping styles, there is relatively little empirical support for the connection between maladaptive coping and other kinds of drug use. The present study employed a cross-sectional design to assess coping and drug use in a sample of 276 methadone maintenance patients. Structural equation modeling was used to assess the factor structure of the coping measure and the relationship between coping and unauthorized drug use. The results suggest that coping and drug use are related in this population and that this relationship is different for Black patients than for White patients.

Problem-solving types among high-risk IDUs: Potential treatment implications

We interviewed 265 cocaine-experienced methadone patients about situations that occasioned their cocaine use and strategies they used to avoid cocaine use. Subjects identified an average of 15 situations that occasioned cocaine use. The three most frequently identified were having the drug present (86% of subjects), being offered the drug (85%) and having money available (83%). Subjects reporting fewer situations also reported longer periods of lifetime abstinence (p < 0.01). A principal components analysis extracted 10 groups of situations that were most frequently identified in combination. Subjects identified a median of seven strategies for avoiding cocaine use; however, there was large inter-subject variability. This variance was not accounted for by demographic variables, employment status or treatment experience. The three strategies identified most frequently were avoiding people and places (81%), thinking about what they could lose (76%) and leaving the situation (66%). The total number and type (reactive vs. proactive) of strategies identified by subjects had no relationship to cocaine abstinence, although four specific strategies (thinking about what could be lost, leaving the situation, moving to a new area and using a different drug) were positively correlated with cocaine abstinence. We discuss implications of these results for clinical practice.