What happens in treatment doesn't stay in treatment: cocaine abstinence during treatment is associated with fewer problems at follow-up

Reduced drug use as an alternative valid outcome in individuals with stimulant use disorders: Findings from 13 multisite randomized clinical trials

BACKGROUND AND AIMS

Total abstinence has historically been the goal of treatment for substance use disorders; however, there is a growing recognition of the health benefits associated with reduced use as a harm reduction measure in stimulant use disorders treatment. We aimed to assess the validity of reduced stimulant use as an outcome measure in randomized controlled trials (RCTs) of pharmacological interventions for stimulant use disorder.

DESIGN

We conducted a secondary analysis of a pooled dataset of 13 RCTs.

SETTING AND PARTICIPANTS

Participants were individuals seeking treatment for cocaine or methamphetamine use disorders (N = 2062) in a wide range of treatment facilities in the United States.

MEASUREMENTS

We validated reduced stimulant use against a set of clinical indicators drawn from harmonized measurements, including severity of problems caused by drug use, comorbid depression, global severity of substance use and improvement, severity of drug-seeking behavior, craving and high-risk behaviors, all assessed at the end of the trial, as well as follow-up urine toxicology. A series of mixed effect regression models was conducted to validate reduction in frequency of use against no reduction in use and abstinence.

FINDINGS

More participants reduced frequency of primary drug use than achieved abstinence (18.0% vs. 14.2%, respectively). Reduced use was significantly associated with decreases in craving for the primary drug [60.1%, 95% confidence interval (CI) = 54.3%-64.7%], drug seeking behaviors (41.0%, 95% CI = 36.6%-45.7%), depression severity (39.9%, 95% CI = 30.9%-48.3%), as well as multiple measures of global improvement in psychosocial functioning and severity of drug-related problems, albeit less strongly so than abstinence. Moreover, reduced use was associated with sustained clinical benefit at follow-up, as confirmed by negative urine tests (adjusted odds ratio compared with those with no reduction in use: 0.50, 95% CI = 0.35-0.71).

CONCLUSION

Reduced frequency of stimulant use appears to be associated with meaningful improvement in various clinical indicators of recovery. Assessment of reduced use, in addition to abstinence, could broaden the scope of outcomes measured in randomized controlled trials of stimulant use disorders and facilitate the development of more diverse treatment approaches.

Percentage of negative urine drug screens as a clinically meaningful endpoint for RCTs evaluating treatment for cocaine use

BACKGROUND

This study examined a threshold based on the percentage of cocaine-negative (CN) urine drug screens (UDS) collected during treatment as a potential meaningful endpoint for clinical trials. We hypothesized that individuals providing at least 75% CN UDS would have better long-term outcomes than those providing less than 75% CN UDS.

METHODS

Two separate pooled datasets of randomized clinical trials conducted at different institutions were used for analyses: one composed of eight trials (N = 760) and the other composed of three trials (N = 416), all evaluating behavioral and/or pharmacological treatments for cocaine use. UDS were collected at least once per week (up to three times per week) during the 8- or 12-week treatment period across all trials, with substance use and psychosocial functioning measured up to 12 months following treatment. Chi-squares and ANOVAs compared within-treatment and follow-up outcomes between the groups.

RESULTS

Compared to those who did not achieve the threshold, participants who achieved the 75%-CN threshold were retained in treatment longer and had a longer period of continuous abstinence, and were more likely to report problem-free functioning. Additionally, participants who achieved the 75%-CN threshold were more likely to report sustained abstinence and better psychosocial functioning throughout a follow-up period up to 12 months than those who did not achieve the threshold.

CONCLUSIONS

A threshold of 75%-CN UDS is associated with short- and long-term clinical benefits. Future clinical trials may consider this a meaningful threshold for defining treatment responders.

Exploring the performance of during-treatment substance use outcome measures in predicting longer-term psychosocial functioning and post-treatment abstinence

BACKGROUND

The selection of appropriate efficacy endpoints in clinical trials has been a long-standing challenge for the substance use disorder field. Using data from a large, multi-site National Drug Abuse Treatment Clinical Trials Network trial (CTN-0044; n=474), this secondary data analysis aimed to explore whether specific proximal (during-treatment) substance use outcome measures predict longer-term improvements in psychosocial functioning and post-treatment abstinence, and whether predictions vary depending on the specific substance (cannabis, cocaine/stimulants, opioids, and alcohol).

METHODS

Generalized linear mixed models examined associations between six during-treatment substance use outcome measures and social functioning impairment (Social Adjustment Scale Self-Report) and severity of psychiatric symptoms (Brief Symptom Inventory-18) at end-of-treatment, and 3- and 6-months after treatment as well as post-treatment abstinence.

RESULTS

Maximum days of consecutive abstinence, proportion of days abstinent, ≥3 weeks of continuous abstinence, and the proportion of urine specimens negative for the primary substance were associated with post-treatment psychiatric and social functioning improvement and abstinence. However, only the effects of abstinence during the last 4 weeks of the treatment period on all three post-treatment outcomes was stable over time and did not differ between primary substance groups. In contrast, complete abstinence during the 12-week treatment period was not consistently associated with functioning improvements.

CONCLUSIONS

Substance use outcome measures capturing the duration of primary substance abstinence during treatment are suitable predictors of post-treatment abstinence and longer-term psychosocial functioning improvement. Binary outcomes, such as end-of-treatment abstinence, may be particularly stable predictors and attractive given their ease of computation and straightforward clinical interpretability.

Detecting change in psychiatric functioning in clinical trials for cocaine use disorder: sensitivity of the Addiction Severity Index and Brief Symptom Inventory

BACKGROUND

Assessment instruments commonly used in clinical trials to measure functional outcomes in substance users may lack sensitivity to detect change during treatment, potentially limiting findings regarding benefits of reduced drug use. This study evaluated the sensitivity of the Addiction Severity Index (ASI) to detect change in psychiatric functioning among cocaine users.

METHODS

Data were pooled across five clinical trials for cocaine use disorder (N = 492) that included a 12-week treatment period and 6-month follow-up. Within-person cohen's d' was used to evaluate effect size of change on the Psychiatric Composite Score of the ASI (ASI-Psych) and Global Severity Index (GSI) of the Brief Symptom Inventory, as well as cocaine use.

RESULTS

Effect sizes were larger for GSI than ASI-Psych from baseline to week 12 (GSI d' = 0.59; ASI-Psych d' = 0.16), and 6-month follow-up (GSI d' = 0.48; ASI-Psych d' = 0.10). For those with non-zero ASI-Psych at baseline (n = 252), medium effect sizes were found over the 12-week period (d' = 0.53) and 6-month follow-up (d' = 0.47). Effect sizes for change in days of cocaine use were most similar to GSI in either sample.

CONCLUSIONS

The ASI Psychiatric Composite Score may have limited sensitivity to detect change in psychiatric functioning among clinical trial participants who reduce cocaine use. It may be useful for detecting change amongst those reporting some psychiatric problems at the start of treatment. Future research should consider an instrument's sensitivity to change when assessing the potential functional benefits of reducing cocaine use.

Targeting white matter neuroprotection as a relapse prevention strategy for treatment of cocaine use disorder: Design of a mechanism-focused randomized clinical trial

Cocaine use continues to be a significant public health problem with limited treatment options and no approved pharmacotherapies. Cognitive-behavioral therapy (CBT) remains the mainstay treatment for preventing relapse, however, people with chronic cocaine use display cognitive impairments that are associated with poor response to CBT. Emerging evidence in animal and human studies suggests that the peroxisome proliferator-activated receptor-gamma (PPAR- γ) agonist, pioglitazone, improves white matter integrity that is essential for cognitive function. This project will determine whether adjunctive use of pioglitazone enhances the effect of CBT in preventing relapse during the early phase of recovery from cocaine use disorder. This paper describes the design of a mechanism-focused phase 2 randomized clinical trial that aims first to evaluate the effects of pioglitazone on targeted mechanisms related to white matter integrity, cognitive function, and cocaine craving; and second, to evaluate the extent to which improvements on target mechanisms predict CBT response. Positive results will support pioglitazone as a potential cognitive enhancing agent to advance to later stage medication development research.

Long-term functioning to provide empirical support for the clinical relevance of treatment outcomes for methamphetamine use disorders

BACKGROUND

Research has yet to empirically evaluate methamphetamine (MA) use outcome measures commonly used to indicate treatment success. Clinically meaningful outcomes must be associated with long-term functioning in important life domains. This study evaluated the association between different MA use outcomes and long-term life-functioning.

METHOD

The data that this study used in its secondary analyses were pooled from two treatment trials for MA use disorders (n = 237). The study conducted multiple regression analyses (with multiple imputation for missing data) to determine the association of six within-treatment MA use outcome measures with problem severity in seven life domains and a proxy measure for overall functioning, measured with the Addiction Severity Index (ASI) and assessed at an 8-month follow-up.

RESULTS

The longest duration of abstinence (LDA) outcome achieved the most consistent performance, being associated with better scores in five of eight ASI outcomes (β ranging from -0.203 to -0.291; p < .01). The complete abstinence during treatment demonstrated the poorest performance and was not significantly associated with any of the ASI outcomes. All other MA use outcome measures were significantly (p < .01) associated with at least one ASI outcome.

CONCLUSION

This study provides empirical support for the use of LDA as a clinically relevant indicator of treatment success for MA use disorders, while also indicating the limitations of using complete abstinence during treatment to determine treatment success. Based on these findings, providers and researchers should use LDA as a primary outcome for MA use disorder treatments and trials.

Clinical effects beyond cocaine use of sustained-release dexamphetamine for the treatment of cocaine dependent patients with comorbid opioid dependence: secondary analysis of a double-blind, placebo-controlled randomized trial

BACKGROUND AND AIMS

Sustained-release (SR) formulations of dexamphetamine and mixed amphetamine salts have shown positive effects in the treatment of patients with a cocaine use disorder. We previously demonstrated the efficacy of SR-dexamphetamine for patients with cocaine dependence in terms of cocaine use reductions. In this secondary analysis, we assessed whether SR-dexamphetamine treatment also improves the health status of these patients.

DESIGN

Multi-centre randomized, double-blind placebo-controlled trial.

SETTING

Four supervised heroin-assisted treatment (HAT) out-patient clinics in the Netherlands. In HAT, methadone treatment-refractory opioid-dependent patients can self-administer individually titrated doses of pharmaceutical grade diacetylmorphine, coprescribed with oral methadone.

PARTICIPANTS

Seventy-three cocaine-dependent patients (90% males; average age = 48.7 years), participating in HAT for their treatment-refractory comorbid opioid dependence.

INTERVENTIONS

Twelve weeks pharmacotherapy with once-daily, supervised intake of two tablets of SR-dexamphetamine (2 × 30 mg/day) or two identical placebo tablets.

MEASUREMENTS

Assessment every 4 weeks: cocaine use (time-line follow-back), physical health (Maudsley Addiction Profile-Health Symptoms Scale), mental health (Brief Symptom Inventory) and illegal activities (Addiction Severity Index). Primary outcome was 'overall health', a dichotomous, multi-domain response index based on physical health, mental health and social functioning.

FINDINGS

Compared with placebo, SR-dexamphetamine resulted in larger increases in the number of cocaine abstinent days (P = 0.004) and the proportion of overall health treatment responders (P = 0.045) from the 4 weeks preceding baseline to the final 4 weeks of treatment. While the number of cocaine abstinent days was not associated with overall health in the total study sample, it was positively associated with overall health among patients in poor overall health at the start of SR-dexamphetamine treatment (n = 50), i.e. patients with the potential to improve on this multi-domain response index (odds ratio = 1.076; 95% confidence interval = 1.025-1.130).

CONCLUSIONS

SR-dexamphetamine reduces cocaine use and may improve clinically relevant health-related outcomes in patients with cocaine dependence who are participating in heroin-assisted treatment for their comorbid heroin dependence.

Patterns of Cocaine Use During Treatment: Associations With Baseline Characteristics and Follow-Up Functioning

OBJECTIVE

Abstinence outcomes are typically prioritized in the treatment of cocaine use disorder while ignoring patterns of low-frequency cocaine use. This study examined patterns of cocaine use frequency during treatment and evaluated how these patterns related to baseline characteristics and functioning outcomes 6 and 12 months after treatment.

METHOD

We used a pooled dataset (N = 720) from seven randomized clinical trials for cocaine use disorder. The Addiction Severity Index (ASI) was used to assess functioning. Repeated-measures latent class analysis was used to derive patterns of cocaine use.

RESULTS

Three patterns were identified: abstinence (10.6%), low-frequency use (approximately 1 day/week; 66.3%), and persistent frequent use (approximately 4 days/week; 23.1%). The low-frequency group was associated with male gender, younger age, and a criminal justice referral. The abstinent group had the highest alcohol problem severity score at baseline. At Month 6, the low-frequency group reported lower problem severity than the persistent frequent use group across multiple ASI areas, including the cocaine use as well as psychological, family, employment, and legal domains. At Month 12, the low-frequency group did not differ from the abstinent group in problem severity on any ASI domain and, relative to the persistent frequent use group, had lower cocaine use and employment problem severity.

CONCLUSIONS

These findings highlight the importance of adopting a harm reduction approach and recognizing the potential clinical benefits associated with nonabstinent outcomes.

Within-treatment frequency of use versus abstinence as a predictor of longitudinal post-treatment follow-up assessments of drug use

BACKGROUND

Abstinence is a widely-used endpoint in clinical trials of stimulant use disorders. A quantitative measure of frequency of use may be a more sensitive endpoint; however, it is important to establish that it is associated with post-treatment drug use. We examine and compare how within-treatment abstinence and frequency of use are related to two post-treatment longitudinal measures of drug use.

METHODS

For each of three existing stimulant use disorder clinical trial datasets, we examined the association between within-treatment frequency of use (based on urine screens), within-treatment abstinence, and post-treatment follow-up assessments of drug use (urine screens and reported days of use). In joint analyses that simultaneously model the effects of within-treatment abstinence and frequency of use, it is possible to discern their relative importance as predictors of post-treatment drug use during the 12 months following the end of treatment.

RESULTS

Results indicate a quantitative measure of within-treatment frequency of use was associated with longitudinal post-treatment follow-up assessments of drug use. Results from joint analyses of post-treatment follow-up drug use assessed by urine screens suggest that within-treatment frequency of use, rather than abstinence per se, is predictive of post-treatment drug use. However, results from joint analyses of self-report of days of use are equivocal.

CONCLUSION

Results lend support to the use of a quantitative measure of within-treatment drug use as an alternative to complete abstinence. They suggest that some within-treatment use that fall short of complete abstinence may potentially represent clinically important improvements given their association with post-treatment drug use.

Clinical validation of reduction in cocaine frequency level as an endpoint in clinical trials for cocaine use disorder

BACKGROUND

Despite calls for non-abstinence endpoints in randomized clinical trials (RCTs) for cocaine use disorder, there is a lack of data validating non-abstinence endpoints. We conducted a clinical validation of reduction in cocaine frequency level as a non-abstinence endpoint in RCTs for cocaine use disorder (CUD).

METHODS

We utilized a pooled dataset (n = 716; 63.6 % male, 51.4 % non-Hispanic white) from seven RCTs for CUD. We specified three cocaine frequency levels at baseline and end of treatment (EOT): abstinence, low frequency (1-4 days/month), and high frequency (5+ days/month). Multiple regression analyses were conducted.

RESULTS

Among the sample, 38.3 % had at least a one-level reduction from baseline to EOT, whereas 61.7 % did not change/increased frequency level. At least a one-level reduction in cocaine frequency level from baseline to EOT versus no change/increase was significantly associated with better functioning up to one year following treatment on measures of cocaine use, as well as psychological, employment, legal, and other drug use problem severity domains of the Addiction Severity Index (ASI). We also conducted analyses only among those at the high frequency level at baseline and found those who reduced to low frequency use at EOT had similar outcomes at follow-up as those who reduced to abstinence.

CONCLUSIONS

At least a one-level reduction in cocaine frequency level from pretreatment to EOT can be a clinically meaningful endpoint given its relation to sustained clinical benefit up to one-year following treatment. These data parallel recent findings regarding reduction in drinking risk level among individuals with alcohol use disorder.

Patterns of Cocaine Use During Treatment: Associations With Baseline Characteristics and Follow-Up Functioning

OBJECTIVE

Abstinence outcomes are typically prioritized in the treatment of cocaine use disorder while ignoring patterns of low-frequency cocaine use. This study examined patterns of cocaine use frequency during treatment and evaluated how these patterns related to baseline characteristics and functioning outcomes 6 and 12 months after treatment.

METHOD

We used a pooled dataset (N = 720) from seven randomized clinical trials for cocaine use disorder. The Addiction Severity Index (ASI) was used to assess functioning. Repeated-measures latent class analysis was used to derive patterns of cocaine use.

RESULTS

Three patterns were identified: abstinence (10.6%), low-frequency use (approximately 1 day/week; 66.3%), and persistent frequent use (approximately 4 days/week; 23.1%). The low-frequency group was associated with male gender, younger age, and a criminal justice referral. The abstinent group had the highest alcohol problem severity score at baseline. At Month 6, the low-frequency group reported lower problem severity than the persistent frequent use group across multiple ASI areas, including the cocaine use as well as psychological, family, employment, and legal domains. At Month 12, the low-frequency group did not differ from the abstinent group in problem severity on any ASI domain and, relative to the persistent frequent use group, had lower cocaine use and employment problem severity.

CONCLUSIONS

These findings highlight the importance of adopting a harm reduction approach and recognizing the potential clinical benefits associated with nonabstinent outcomes.

Short and long-term improvements in psychiatric symptomatology to validate clinically meaningful treatment outcomes for cocaine use disorders

BACKGROUND

Substantial efforts have been made to identify clinically meaningful non-abstinence cocaine use outcomes by establishing associations between targeted drug use outcomes and long-term functional improvements. Psychiatric symptomatology is prevalent among those seeking treatment for cocaine use disorder (CUD). Establishing an association between cocaine use outcomes and improvements in psychiatric symptomatology would support clinical validity to these outcome measures.

METHOD

With data pooled from 5 clinical trials evaluating treatment for CUD (n = 474) multiple linear mixed models were conducted to determine how five specific cocaine use outcome measures performed in terms of improvements in psychiatric symptomatology assessed with the Brief Symptom Inventory (BSI) at baseline, end-of-treatment and 6-month follow-up.

RESULTS

Three outcome measures performed comparably well (maximum days of consecutive abstinence, 3 or more weeks of abstinence and end-of-treatment abstinence), in that they consistently predicted improvements in several BSI composite scores at the end-of-treatment and follow-up. The poorer-performing outcome measures were complete abstinence during treatment, percentage of negative urinalysis results and percentage of days abstinent. Improvements in the BSI's global index of distress, positive symptom total, as well as depression, interpersonal sensitivity, obsessive-compulsion, phobic-anxiety and psychoticism dimensions were consistently associated with outcome effects, while anxiety, hostility, paranoid ideation and somatization were not.

CONCLUSION

The consistent short and long-term association of three outcome measures evaluated here (maximum days of consecutive abstinence, 3 or more weeks of abstinence and end-of-treatment abstinence) with improvements psychiatric symptomatology adds support to their clinical relevance as well as their adoption in trials and treatments for CUD.

"I's" on the prize: A systematic review of individual differences in Contingency Management treatment response

Contingency Management is an evidence-based treatment for substance use disorders with strong potential for measurement-based customization. Previous work has examined individual difference factors in Contingency Management treatment response of potential relevance to treatment targeting and adaptive implementation; however, a systematic review of such factors has not yet been conducted. Here, we summarize and evaluate the existing literature on patient-level predictors, mediators, and moderators of Contingency Management treatment response in stimulant and/or opioid using outpatients - clinical populations most frequently targeted in Contingency Management research and clinical practice. Our search strategy identified 648 unique, peer-reviewed publications, of which 39 met full inclusion criteria for the current review. These publications considered a variety of individual difference factors, including (1) motivation to change and substance use before and during treatment (8/39 publications), (2) substance use comorbidity and chronicity (8/39 publications), (3) psychiatric comorbidity and severity (8/39 publications), (4) medical, legal, and sociodemographic considerations (15/39 publications), and (5) cognitive-behavioral variables (1/39 publications). Contingency Management was generally associated with improved treatment outcomes (e.g., longer periods of continuous abstinence, better retention), regardless of individual difference factors; however, specific patient-level characteristics were associated with either an enhanced (e.g., more previous treatment attempts, history of sexual abuse, diagnosis of antisocial personality disorder) or diminished (e.g., complex post-traumatic stress symptoms, pretreatment benzodiazepine use) response to Contingency Management. Overall, the current literature is limited but existing evidence generally supports greater benefits of Contingency Management in patients who would otherwise have a poorer prognosis in standard outpatient care. It was also identified that the majority of previous work represents a posteriori analysis of pre-existing clinical samples and has therefore rarely considered pre-specified, hypothesis-driven individual difference factors. We therefore additionally highlight patient-level factors that are currently understudied, as well as promising future directions for measurement-based treatment adaptations that may directly respond to patient traits and states to improve Contingency Management effectiveness across individuals and over time.

Randomized controlled trial of enhanced telephone monitoring with detoxification patients: 3- and 6-month outcomes

Telehealth interventions have the potential to deter repeated detoxification episodes and improve outcomes. Using a sample of 298 detoxification inpatients, this randomized controlled trial compared Enhanced Telephone Monitoring (ETM) to usual care (UC) on the primary outcome of reducing subsequent detoxification, and secondary outcomes of linking patients to addiction treatment and mutual-help, and patients' experience of improved substance use and mental health outcomes. At the 3-month follow-up (i.e., at the end of the ETM intervention), compared to UC patients, ETM patients were significantly less likely to have received additional inpatient detoxification, but no more likely to have participated in 12-step groups or received outpatient addiction treatment. Even so, ETM patients had better alcohol, drug, and mental health outcomes. In contrast, at the 6-month follow-up, patients in ETM and UC generally did not differ on primary or secondary outcomes. Findings suggest that ETM deters additional detoxification episodes while the intervention is ongoing, but not after the intervention ends. Because telephone monitoring is low-intensity and low-cost, its extension over time may help reduce repeated detoxifications.

Systematic review of outcome domains and measures used in psychosocial and pharmacological treatment trials for cannabis use disorder

Cannabis use disorder (CUD) is prevalent and demand for treatment is increasing, yet few individuals engage in formal treatment and the efficacy of established interventions for CUD is modest. Existing clinical trials evaluating psychosocial and pharmacological treatments for CUD have incorporated a wide variety of measures for assessing cannabis use outcomes, including abstinence, self-reported frequency and quantity used, withdrawal, use/dependence severity, and other psychosocial outcomes. The heterogeneity of measures and outcomes has limited quantitative analyses of the comparative effectiveness of existing interventions. The purpose of this systematic review is to: 1) identify and characterize approaches for measuring cannabis use in existing CUD intervention trials, including abstinence, frequency and quantity of use, and 2) summarize measures used to assess treatment efficacy in other outcome domains (e.g., cannabis use severity, psychosocial functioning, cannabis withdrawal), and provide a platform for future research to evaluate which outcome measures are most likely to reflect treatment efficacy and clinically significant improvement in other outcome domains.

What defines a clinically meaningful outcome in the treatment of substance use disorders: reductions in direct consequences of drug use or improvement in overall functioning?

BACKGROUND

Sustained abstinence is currently the only accepted end-point for pharmacotherapy trials for most substance use disorders (SUD), with the exception of alcohol. Despite recent efforts, the identification of a non-abstinence alternative as a clinically meaningful end-point for drug use trials has been elusive.

ARGUMENT AND ANALYSIS

The current standard for establishing a clinically meaningful outcome in SUD trials is to demonstrate that a reduction in drug use is associated with improvement in long-term functioning, but data indicate relatively weak associations between drug use and various psychosocial problem domains. This may be because assessments used most commonly to measure an individual's functioning do not specify whether aspects of functioning are a direct consequence of drug use. The acceptance of a non-abstinence-based end-point for alcohol use disorder trials was supported in part through associations with reductions in alcohol-related consequences, although measures designed to assess the direct consequences of drug use are rarely included in drug treatment efficacy trials.

CONCLUSIONS

The field of substance use disorders should include measures of negative psychosocial and health consequences of drug use, as opposed to overall functioning, in the effort to establish meaningful non-abstinence-based end-points.

Initial validation of a proxy indicator of functioning as a potential tool for establishing a clinically meaningful cocaine use outcome

BACKGROUND

Establishing a non-abstinence cocaine use outcome as clinically meaningful has been elusive, in part due to the lack of association between cocaine use outcomes and meaningful indicators of long-term functioning.

METHODS

Using data pooled across 7 clinical trials evaluating treatments for cocaine (N=718), a dichotomous indicator of functioning was created to represent a meaningful outcome ('problem-free functioning' - PFF), defined as the absence of problems across non-substance-related domains on the Addiction Severity Index. Its validity was evaluated at multiple time points (baseline, end-of-treatment, terminal follow-up) and used to explore associations with cocaine use.

RESULTS

The percentage of participants meeting PFF criteria increased over time (baseline=18%; end-of-treatment=32%; terminal follow-up=37%). At each time point, ANOVAs indicated those who met PFF criteria reported significantly less distress on the Brief Symptom Inventory and less perceived stress on the Perceived Stress Scale. Generalized linear models indicated categorical indices of self-reported cocaine use at the end of treatment were predictive of the probability of meeting PFF criteria during follow-up (β=-0.01, p<0.01; 95% CI: -0.008 to -0.003), with those reporting 0days or 1-4days ('occasional' use) in the final month of treatment showing an increased likelihood of achieving PFF.

CONCLUSIONS

Initial validation of a proxy indicator of problem-free functioning demonstrated criterion validity and sensitivity to change over time. Frequency of cocaine use in the final month of treatment was associated with PFF during follow-up, with strongest associations between PFF and abstinence or 'occasional' use.

Examining Risk for Frequent Cocaine Use: Focus on an African American Treatment Population

BACKGROUND

Cocaine use and its consequences are disproportionately higher and more severe among African Americans compared to other ethnic/racial groups.

OBJECTIVES

The aims of this study were to examine a risk model specific for African American users and assess whether risk varies as a function of sex.

METHODS

270 African American adults in a residential drug treatment facility completed measurements assessing first and past year crack/cocaine use frequency, childhood trauma, and stress reactivity. Multiple linear regression analysis was used to examine the unique effect of each predictor variable on past year crack/cocaine frequency. Sex was included as a moderator variable in the regression analysis.

RESULTS

All predictor variables were positively correlated with past year crack/cocaine use. However, sex differences were also observed: females reported higher rates of childhood emotional abuse, childhood sexual abuse, and stress reactivity-as well as past year crack use and cocaine use-than males. Regression analyses were performed with sex, first year use, and stress reactivity emerging as the only significant predictors for frequency of crack and cocaine use among all study participants. Moreover, sex differences were observed in the influence of first year crack use frequency on past year crack use frequency, such that the effect was stronger for males than for females. Conclusion/Importance: This study offers a clearer understanding of the risk factors for crack and cocaine abuse specific to African Americans, as well as sex specific pathways to risk, providing useful implications for future prevention and treatment efforts.

Measures of outcome for stimulant trials: ACTTION recommendations and research agenda

BACKGROUND

The development and approval of an efficacious pharmacotherapy for stimulant use disorders has been limited by the lack of a meaningful indicator of treatment success, other than sustained abstinence.

METHODS

In March, 2015, a meeting sponsored by Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) was convened to discuss the current state of the evidence regarding meaningful outcome measures in clinical trials for stimulant use disorders. Attendees included members of academia, funding and regulatory agencies, pharmaceutical companies, and healthcare organizations. The goal was to establish a research agenda for the development of a meaningful outcome measure that may be used as an endpoint in clinical trials for stimulant use disorders.

RESULTS AND CONCLUSIONS

Based on guidelines for the selection of clinical trial endpoints, the lessons learned from prior addiction clinical trials, and the process that led to identification of a meaningful indicator of treatment success for alcohol use disorders, several recommendations for future research were generated. These include a focus on the validation of patient reported outcome measures of functioning, the exploration of patterns of stimulant abstinence that may be associated with physical and/or psychosocial benefits, the role of urine testing for validating self-reported measures of stimulant abstinence, and the operational definitions for reduction-based measures in terms of frequency rather than quantity of stimulant use. These recommendations may be useful for secondary analyses of clinical trial data, and in the design of future clinical trials that may help establish a meaningful indicator of treatment success.

The development and evaluation of stimulant treatment programmes

PURPOSE OF REVIEW

To summarize the recent literature (1st January 2014-1st February 2015) on stimulant treatment programme evaluations, and highlight key areas for future programme development.

RECENT FINDINGS

Advances have been made in addressing both sexual risks and stimulant use among gay and bisexual men in the United States, and in adapting evidence-based resource-intense interventions to real-world settings. Programme outcome measures increasingly include changes in substance use as well as health and wellbeing indicators and measures of risk.

SUMMARY

Future programme directions include: expansion of the psychosocial repertoire to include narrative and mindfulness-based therapies; web-based programme delivery; sex-sensitive programming to attract and retain women; comprehensive programming to address coexisting mental and physical illness and polysubstance use (including tobacco smoking); and improving accessibility to promote early intervention. Comparability of evaluation data can be improved by developing standardized tools particularly for measuring change in sexual-risk behavior. The use of new statistical techniques can address the lack of comparison populations.

Prompted to treatment by the criminal justice system: Relationships with treatment retention and outcome among cocaine users

BACKGROUND AND OBJECTIVES

A substantial portion of individuals entering treatment for substance use have been referred by the criminal justice system, yet there are conflicting reports regarding treatment engagement and outcome differences compared to those not referred. This study examined baseline characteristic and treatment outcome differences among cocaine-dependent individuals participating in cocaine treatment randomized trials.

METHODS

This secondary analysis pooled samples across five completed randomized controlled trials, resulting in 434 participants. Of these, 67 (15%) were prompted to treatment by the criminal justice system.

RESULTS

This subsample of criminal justice prompted (CJP) individuals did not differ from those not prompted by the criminal justice system in terms of gender, race/ethnicity, marital status, or age. However, the CJP group reported more years of regular cocaine use, more severe employment and legal problems, as well as less readiness to change prior to treatment. Treatment outcomes did not differ significantly from those without a criminal justice prompt, and on some measures the outcomes for CJP group were better (e.g., percentage of days cocaine abstinent, number of therapy sessions attended).

DISCUSSION AND CONCLUSIONS

These findings suggest that being prompted to treatment by the criminal justice system may not lead to poorer treatment engagement or substance use outcomes for individuals participating in randomized controlled treatment trials.

SCIENTIFIC SIGNIFICANCE

Despite some baseline indicators of poorer treatment prognosis, individuals who have been prompted to treatment by the criminal justice system have similar treatment outcomes as those presenting to treatment voluntarily.

Smokers versus snorters: do treatment outcomes differ according to route of cocaine administration?

Smoking cocaine achieves maximal concentration and effect far more rapidly than through the intranasal ("snorting") route, and it is associated with greater propensity for dependence and more severe consequences. However, very little is known about differences in treatment outcome according to route of administration. This study compared treatment outcomes, such as frequency of cocaine use and Addiction Severity Index (ASI) composite scores, by primary route of cocaine administration (smoking vs. intranasal) among a pooled sample of 412 cocaine-dependent individuals participating in 1 of 5 randomized clinical trials. The majority (80%) reported smoking as their primary route of cocaine administration. Overall, results indicated better cocaine use outcomes both during the treatment phase and through a 12-month follow-up period for intranasal users compared to smokers, although not all differences reached statistical significance. Intranasal users remained in treatment longer, F(1, 408) = 3.55, p < .05, and showed a trend toward achieving longer periods of sustained abstinence within treatment, F(1, 378) = 2.68, p = .08, as well as less use over time during the follow-up period than smokers (Time × Route: t = 1.87, p = .06). Also, intranasal users' ASI cocaine composite score decreased more than smokers, but there were overall decreases in the other ASI domains for all participants over the course of the study period. These results suggest that intranasal users may achieve better cocaine use outcomes than smokers, yet this doesn't appear to translate to differential changes in the severity of problems experienced in other life areas.