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

Examining cocaine use reductions and long-term outcomes in two clinical trials of continuing care for cocaine dependence

BACKGROUND

There is a need to identify clinically meaningful non-abstinent endpoints for cocaine use disorder (CUD) clinical trials. In this study, we sought to replicate and extend prior work validating reductions in cocaine use frequency levels as an endpoint by examining associations between reductions in cocaine use frequency and long-term functioning outcomes.

METHODS

We conducted a secondary analysis of two randomized clinical trials (N = 445; 77.5 % male; mean age = 42.18 years; 86.5 % Black, 10.8 % non-Hispanic white) that evaluated telephone-based continuing care for a 12- and 24-month period. Cocaine use frequency levels, measured with the Timeline Followback, were (1) abstinence (no past-month cocaine use), (2) low-frequency use (1-4 days of use/month), and (3) high-frequency use (5+ days of use/month).

RESULTS

Among those who completed the 12-month follow-up (n = 392), most reduced from high-frequency use at baseline to abstinence at the 12-month follow-up (n = 243; 62.0 %). An additional 21.2 % (n = 83) reported either high-to-low-frequency use (n = 35; 8.9 %) or low use-to-abstinence (n = 48; 12.2 %); 16.8 % of participants (n = 66) did not change or increased their cocaine frequency level. Compared to those who had no change/increases in frequency levels, at least a one-level reduction from baseline to 12-month follow-up (i.e., high-to-low-frequency use, high-to-abstinence, low-to-abstinence) was concurrently associated with lower levels of negative consequences at the 12-month follow-up and prospectively with lower levels of cocaine use and consequences at 24-month follow-up, with effect sizes in the medium-to-large range. Those who reduced to abstinence generally had fewer drug use consequences at the 12-month follow-up than those who reduced to a low-frequency level; however, these groups did not significantly differ on any outcomes at the 24-month follow-up.

CONCLUSIONS

Categorical reductions in cocaine use frequency levels, including those short of abstinence, are associated with less cocaine use and lower problem severity up to two years following treatment entry. Low-frequency cocaine use following the initial treatment phase does not appear to forebode worsening functioning, such as escalations in cocaine use.

Contingency Management for Drug Use Disorders: Meta-Analysis and Application of Tolin's Criteria

Several professional organizations and federal agencies recommend contingency management (CM) as an empirically supported treatment for drug use disorder. However, the release of the "Tolin criteria" warrants an updated recommendation. Using this methodology, five meta-analyses (84 studies, 11,000 participants) were reviewed. Two meta-analyses were rated moderate quality, and three were rated low or critically low quality. Comparator conditions included active treatment, placebo, treatment as usual, and no treatment. The primary outcome was abstinence. Considering only the moderate quality meta-analyses, the effect of CM versus control on posttreatment abstinence was d = 0.54 [0.43, 0.64] and follow-up abstinence was d=0.08 [0.00, 0.16]. A "strong" recommendation was provided for CM as an empirically supported treatment for drug use disorder.

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.

What's race got to do with it? Factors contributing to self-change from cocaine use disorder among Black adults

INTRODUCTION

A substantial number of people with substance use disorders recover without formal treatment, though we know little about the process of self-change among Black adults with cocaine use disorder (CUD) and whether racism contributes to the development of CUD and these adults' process of self-change.

METHODS

The study team conducted qualitative interviews with 29 Black adults using a narrative and phenomenological approach. At the time of the interview, all participants met criteria for DSM-5 CUD prior to the past year but did not meet criteria for CUD in the past year and reported that they reduced their cocaine use without formal treatment. Participants completed a qualitative interview followed by the UConn Racial/Ethnic Stress & Trauma Survey. Thematic analyses informed key themes from the qualitative interviews.

RESULTS

Qualitative analyses indicated several major factors that contributed to self-change from CUD: racial identity, responsibility to family, social regard, spirituality, turning point for change, and changing one's environment. These results highlight that self-change from CUD is a complex, ongoing, and multifaceted process. The identified themes align with several theories of recovery, including social control theory and the theory of stress and coping. Furthermore, the results suggest that experiences of racism are common among Black adults recovering from CUD, and that the multiple strategies employed for coping with racism may be consistent with the process of self-change.

CONCLUSIONS

This study shows that multiple race-related factors contribute to the development of, maintenance of, and self-change from CUD among Black adults. Better understanding these factors can help to inform drug treatment.

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.

Deficits in consummatory reward relate to severity of cocaine use

BACKGROUND AND AIMS

Identifying modifiable neuropsychological factors associated with more severe CUD could improve CUD treatment. Impairments in processing of non-drug rewards may be one such factor. This study assessed the relationship between reward functioning and cocaine use severity using multi-modal measures of three distinct reward functions: consummatory reward (pleasure or "liking"); motivational reward ("wanting") and reward learning.

METHODS

Fifty-three adults with at least moderate CUD completed self-report and behavioral measures of consummatory reward, motivational reward and reward learning, and a composite cocaine use severity measure including quantity, frequency and life impacts of cocaine use. We conducted parallel Frequentist and Bayesian multiple regressions with measures of reward functioning as predictors of cocaine use severity.

RESULTS

Less self-reported ability to experience pleasure, a hypothesized measure of consummatory reward, significantly predicted greater severity after adjustment for covariates and multiple hypothesis testing, β = 0.39, t(38) = 2.86, p = 0.007. Bayesian analyses confirmed a highly likely association between severity and ability to experience pleasure, and provided moderate evidence for associations with willingness to exert effort and reward learning.

CONCLUSIONS

Our results suggest that less experience of subjective pleasure is related to greater cocaine use severity. This cross-sectional study cannot establish whether differences in consummatory reward are pre-existing, a result of CUD, or both. However, these results suggest interventions focused on increasing subjective pleasure, such as mindful "savoring", should be investigated for CUD.

Selecting the appropriate hurdles and endpoints for pentilludin, a novel antiaddiction pharmacotherapeutic targeting the receptor type protein tyrosine phosphatase D

Substance use disorders provide challenges for development of effective medications. Use of abused substances is likely initiated, sustained and "quit" by complex brain and pharmacological mechanisms that have both genetic and environmental determinants. Medical utilities of prescribed stimulants and opioids provide complex challenges for prevention: how can we minimize their contribution to substance use disorders while retaining medical benefits for pain, restless leg syndrome, attention deficit hyperactivity disorder, narcolepsy and other indications. Data required to support assessments of reduced abuse liability and resulting regulatory scheduling differs from information required to support licensing of novel prophylactic or therapeutic anti-addiction medications, adding further complexity and challenges. I describe some of these challenges in the context of our current efforts to develop pentilludin as a novel anti-addiction therapeutic for a target that is strongly supported by human and mouse genetic and pharmacologic studies, the receptor type protein tyrosine phosphatase D (PTPRD).

Logical fallacies and misinterpretations that hinder progress in translational addiction neuroscience

Substance use disorders (SUDs) are heterogeneous and complex, making the development of translationally predictive rodent and nonhuman primate models to uncover their neurobehavioral underpinnings difficult. Neuroscience-focused outcomes have become highly prevalent, and with this, the notion that SUDs are disorders of the brain embraced as a dominant theoretical orientation to understand SUD etiology and treatment. These efforts, however, have led to few efficacious pharmacotherapies, and in some cases (as with cocaine or methamphetamine), no pharmacotherapies have translated from preclinical models for clinical use. In this theoretical commentary, we first describe the development of animal models of substance use behaviors from a historical perspective. We then define and discuss three logical fallacies including 1) circular explanation, 2) affirming the consequent, and 3) reification that can apply to developed models. We then provide three case examples in which conceptual or logical issues exist in common methods (i.e., behavioral economic demand, escalation, and reinstatement). Alternative strategies to refocus behavioral models are suggested for the field to better bridge the translational divide between animal models, the clinical condition of SUDs, and current and future regulatory pathways for intervention development.

Contingency management for treatment attendance: A meta-analysis

BACKGROUND

Treatment providers have applied contingency management (CM) treatment, an intervention that often rewards individuals for drug abstinence (i.e., ABS CM), to treatment engagement as well. However, we know little about the magnitude of treatment effects when providers target attendance behaviors (i.e., ATT CM).

METHODS

This study conducted a systematic search to identify studies that included ATT CM, either in isolation or in combination with ABS CM. The study used meta-analysis to estimate the effect size of ATT CM and ABS CM + ATT CM on treatment attendance and drug abstinence. We identified a total of 10 studies including 12 CM treatments (6 ATT CM and 6 ABS CM + ATT CM) with 1841 participants.

RESULTS

Results indicated a moderate effect (d = 0.47, 95% confidence interval (CI) [0.25, 0.69]) of ATT CM on attendance relative to non-reward active comparison conditions. Frequency of rewards was significantly associated with larger effect sizes. Results also indicated a small effect (d = 0.22, 95% CI [0.12, 0.33]) of ATT CM on abstinence outcomes relative to nonreward comparisons, p < 0.001. The study found no significant differences in attendance or abstinence between ATT CM and ABS CM + ATT CM (p's > 0.05).

CONCLUSION

Overall, the results supported ATT CM for increasing treatment engagement, with smaller effects on abstinence. Effects on abstinence were smaller than those observed in prior meta-analyses focused on ABS CM. No significant differences existed in attendance or abstinence outcomes between ATT CM and ABS + ATT CM. However, future studies are needed to experimentally compare ABS CM + ATT CM to ABS CM, and ATT CM to determine additive effects. Clinics implementing CM should consider the differential effects between ATT CM and ABS CM when selecting target behavior(s).

Expanding the continuum of substance use disorder treatment: Nonabstinence approaches

Only a small minority of people with substance use disorders (SUDs) receive treatment. A focus on abstinence is pervasive in SUD treatment, defining success in both research and practice, and punitive measures are often imposed on those who do not abstain. Most adults with SUD do not seek treatment because they do not wish to stop using substances, though many also recognize a need for help. This narrative review considers the need for increased research attention on nonabstinence psychosocial treatment of SUD - especially drug use disorders - as a potential way to engage and retain more people in treatment, to engage people in treatment earlier, and to improve treatment effectiveness. We describe the development of nonabstinence approaches within the historical context of SUD treatment in the United States, review theoretical and empirical rationales for nonabstinence SUD treatment, and review existing models of nonabstinence psychosocial treatment for SUD among adults to identify gaps in the literature and directions for future research. Despite significant empirical support for nonabstinence alcohol interventions, there is a clear gap in research examining nonabstinence psychosocial treatment for drug use disorders. Future research must test the effectiveness of nonabstinence treatments for drug use and address barriers to implementation.

Interim opioid agonist treatment for opioid addiction: a systematic review

Background

Opioid use disorder is a public health problem and treatment variability, coverage and accessibility poses some challenges. The study’s objective is to review the impact of interim opioid agonist treatment (OAT), a short-term approach for patients awaiting standard OAT, in terms of treatment retention, access to standard OAT, quality of life and satisfaction with treatment.

Method

We conducted a systematic review searching MEDLINE, EMBASE, PsycINFO, and CENTRAL up to May 2020. Due to variability between studies and outcome measurements, we did not pool effect estimates and reported a narrative synthesis of findings rating their certainty according to GRADE.

Results

We identified 266 unique records and included five randomized trials with some limitations in risk of bias and one observational study limited by selection bias. The studies assessed similar approaches to interim OAT but were compared to three different control conditions. Four studies reported on treatment retention at 4 months or less with no significant differences between interim OAT and waiting list or standard OAT. Two studies reported treatment retention at 12 months with no differences between interim OAT and standard OAT. Two trials assessed access to standard OAT and showed significant differences between interim OAT and waiting list for standard OAT. We rated the quality of evidence for these outcomes as moderate due to the impact of risk of bias. Data on quality of life or satisfaction with treatment was suboptimal.

Conclusions

Interim OAT is likely more effective than a waiting list for standard OAT in access to treatment, and it is probably as effective as standard OAT regarding treatment retention.

PROSPERO registration CRD42018116269.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12954-022-00592-x.

Neural classification of internet gaming disorder and prediction of treatment response using a cue-reactivity fMRI task in young men

BACKGROUND

Neural mechanisms underlying internet gaming disorder (IGD) are important for diagnostic considerations and treatment development. However, neurobiological underpinnings of IGD remain relatively poorly understood.

METHODS

We employed multi-voxel pattern analysis (MVPA), a machine-learning approach, to examine the potential of neural features to statistically predict IGD status and treatment outcome (percentage change in weekly gaming time) for IGD. Cue-reactivity fMRI-task data were collected from 40 male IGD subjects and 19 male healthy control (HC) subjects. 23 IGD subjects received 6 weeks of craving behavioral intervention (CBI) treatment. MVPA was applied to classify IGD subjects from HCs and statistically predict clinical outcomes.

RESULTS

MVPA displayed a high (92.37%) accuracy (sensitivity of 90.00% and specificity of 94.74%) in the classification of IGD and HC subjects. The most discriminative brain regions that contribute to classification were the bilateral middle frontal gyrus, precuneus, and posterior lobe of the right cerebellum. MVPA statistically predicted clinical outcomes in the craving behavioral intervention (CBI) group (r = 0.48, p = 0.0032). The most strongly implicated brain regions in the prediction model were the right middle frontal gyrus, superior frontal gyrus, supramarginal gyrus, anterior/posterior lobes of the cerebellum and left postcentral gyrus.

CONCLUSIONS

The findings about cue-reactivity neural correlates could help identify IGD subjects and predict CBI-related treatment outcomes provide mechanistic insight into IGD and its treatment and may help promote treatment development efforts.

The relationship of frequency of cocaine use to substance and psychiatric disorders in the U.S. general population

BACKGROUND

In clinical trials of pharmacotherapy for substance use, abstinence is the primary endpoint accepted by regulatory agencies. However, this endpoint could be overly restrictive, impeding efforts to identify effective medications for cocaine use disorder. To examine non-abstinent gradations in cocaine use as potential indicators of improvement, we investigated the relationship of frequency of cocaine use to clinical correlates in national survey data.

METHODS

Lifetime cocaine users (n = 2501) were interviewed in the National Epidemiological Survey on Alcohol and Related Conditions (NESARC) in 2001-2002 and re-interviewed in 2004-2005. Adjusted odds ratios (aORs) indicated associations between heaviest frequency of cocaine use and use of other substances, DSM-IV substance use disorders, psychiatric disorders, and change between 2001-2002 and 2004-2005. The reference category for all aORs was non-users.

RESULTS

Greater lifetime cocaine use frequency was associated with lifetime cocaine, alcohol, and cannabis dependence (aOR for a linear trend = 2.80, 1.22, 1.22, respectively) and past-year cocaine, alcohol, and cannabis dependence (aOR = 1.78, 1.13, 1.16, respectively). Greater lifetime cocaine use frequency was associated with past-year depressive, panic, and generalized anxiety disorders (aOR = 1.07, 1.09, 1.12, respectively). Among cocaine users in 2001-2002, compared to the reference group using less than monthly, use ≥1x/week and use 1-3 times a month was associated with cocaine use disorder in 2004-2005 (aOR = 2.13 and aOR = 1.67, respectively).

CONCLUSION

Gradations in risk for dependence on cocaine, other substances and psychiatric disorders by frequency of cocaine use indicates a promising direction for more sensitive outcome measures of treatment effects on cocaine outcomes than binary indicators (e.g., any use vs. none). Study results add to findings suggesting that non-abstinent measures might be useful indicators of treatment efficacy in clinical trials.

Patterns of reduced use and abstinence in multi-site randomized controlled trials of pharmacotherapies for cocaine and methamphetamine use disorders

BACKGROUND

Many individuals with cocaine or methamphetamine use disorders who enter treatment do not achieve abstinence but reduce their use of the target drug. We aimed to compare change in pattern of drug use (i.e., achieving "abstinence", "reduced use" or no reduction in use) among participants in randomized controlled trials (RCTs) of treatment of cocaine and methamphetamine use disorder, irrespective of the type of treatment.

METHODS

The data were drawn from 10 multi-site pharmacotherapy RCTs of cocaine (n = 1,134) and methamphetamine (n = 555) use disorders. The outcome patterns and their sociodemographic and clinical correlates were compared in cocaine and methamphetamine RCTs, using multinomial logistic regression models. Analyses were adjusted for missing data, clustering within RCTs, socio-demographic and baseline clinical characteristics, and treatment arms.

RESULTS

Those in cocaine RCTs were more likely to experience reduced use compared to participants in methamphetamine RCTs (20.6% vs. 13.2%, respectively), but less likely to experience "abstinence" (7.6% vs. 20.3%; Chi-squared = 14.20, df = 2, P < 0.001). Differences in "abstinence" persisted after adjustment for baseline covariates. Association of sociodemographic and clinical correlates with outcomes differed in cocaine and methamphetamine RCTs.

CONCLUSION

A sizeable proportion of individuals in RCTs of pharmacological treatment for stimulant use disorder who do not attain "abstinence" nevertheless reduce their use. The outcome patterns of drug use are different for cocaine and methamphetamine use disorders and reliance on abstinence as the sole outcome may obscure these differences.

Beyond abstinence and relapse II: momentary relationships between stress, craving, and lapse within clusters of patients with similar patterns of drug use

RATIONALE

Given that many patients being treated for opioid-use disorder continue to use drugs, identifying clusters of patients who share similar patterns of use might provide insight into the disorder, the processes that affect it, and ways that treatment can be personalized.

OBJECTIVES AND METHODS

We applied hierarchical clustering to identify patterns of opioid and cocaine use in 309 participants being treated with methadone or buprenorphine (in a buprenorphine-naloxone formulation) for up to 16 weeks. A smartphone app was used to assess stress and craving at three random times per day over the course of the study.

RESULTS

Five basic patterns of use were identified: frequent opioid use, frequent cocaine use, frequent dual use (opioids and cocaine), sporadic use, and infrequent use. These patterns were differentially associated with medication (methadone vs. buprenorphine), race, age, drug-use history, drug-related problems prior to the study, stress-coping strategies, specific triggers of use events, and levels of cue exposure, craving, and negative mood. Craving tended to increase before use in all except those who used sporadically. Craving was sharply higher during the 90 min following moderate-to-severe stress in those with frequent use, but only moderately higher in those with infrequent or sporadic use.

CONCLUSIONS

People who share similar patterns of drug-use during treatment also tend to share similarities with respect to psychological processes that surround instances of use, such as stress-induced craving. Cluster analysis combined with smartphone-based experience sampling provides an effective strategy for studying how drug use is related to personal and environmental factors.

Hair Testing for Classic Drugs of Abuse to Monitor Cocaine Use Disorder in Patients Following Transcranial Magnetic Stimulation Protocol Treatment

Simple Summary

Hair testing for classic drugs of abuse offers the possibility of longer detection times (for drug substances) when compared to urine analysis. Hair analysis is routinely used to detect drug abuse in forensic cases and clinical toxicology, whereas it is rarely used at addiction clinics to monitor the clinical efficacy of therapeutic interventions. Here, we explore for the first time whether hair analysis might represent a valid tool to track the clinical improvements in a population of patients with cocaine use disorder (CocUD) who underwent a repetitive transcranial magnetic stimulation (rTMS) treatment.

Abstract

In recent years, hair has become an alternative biological specimen for drug testing in the fields of forensic and clinical toxicology. The advantages of hair testing include larger detection windows (months/years), depending on the length of the hair shaft, compared to those of urine/blood (hours to 2–4 days for most drugs). Segmental hair analysis can disclose a month-to-month (considering 1 cm segment cuts) information of drug exposure (single or repeated) and potentially identify patterns of drug use/administration. Repetitive transcranial magnetic stimulation (rTMS) was recently proposed as a valid tool for therapeutic purposes in addictions, including cocaine use disorder (CocUD). Here, we proposed hair testing analyses of classic drugs of abuse in a clinical setting to monitor the clinical changes in treatment-seeker CocUD patients undergoing protocol treatments with rTMS stimulating the left dorsolateral prefrontal cortex (l-DLPFC). We collected hair samples from nine CocUD patients at different stages from the beginning of treatments. Hair sample analyses revealed significant changes in the patterns of cocaine use, according to the negativity of urine screening tests and the clinical reductions of craving. These data, albeit preliminary, suggest that hair testing analysis of classic drugs of abuse could be extended to clinical settings to monitor the clinical efficacy of innovative therapeutic interventions, such as rTMS.

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.

A Retrospective Comparative Study in Patients With Cocaine Use Disorder Comorbid With Attention Deficit Hyperactivity Disorder Undergoing an rTMS Protocol Treatment

Background: Adult attention-deficit/hyperactivity disorder (ADHD) is associated with high comorbidity with other psychiatric diseases, including cocaine use disorder (CocUD). Given the common fronto-striatal dysfunction, ADHD patients often use cocaine as self-medication for ameliorating symptoms by increasing striatal dopamine release. Yet, comorbidity with ADHD is related to poor treatment outcomes. CocUD has been treated with transcranial magnetic stimulation (TMS), but no studies investigated the outcomes in patients comorbid with ADHD. Methods: Twenty-two ADHD/CocUD and 208 CocUD-only participants received a high-frequency (15 Hz) rTMS treatment stimulating the left-DLPFC. We investigated whether both groups of patients shared similar demographic and clinical characteristics at baseline. Then, we monitored the effect of treatment testing for potential differences between groups. Results: At baseline demographic, toxicology and clinical features were not different between the two groups except for global severity index (GSI from SCL-90): patients of ADHD/CocUD group reported higher general symptomatology compared to the CocUD-only group. Concerning the effect of treatment, both groups significantly improved over time regarding cocaine use, craving, and other negative affect symptoms. No differences were observed between groups. Conclusions: To our knowledge, this is the first study comparing the demographic characterization and rTMS clinical improvements of patients with a dual diagnosis of ADHD and CocUD against CocUD-only patients. Cocaine use and common self-reported withdrawal/abstinence symptoms appear to benefit from rTMS treatment with no differences between groups. Future studies are needed to further investigate these preliminary results.

Identification of Typologies of Cocaine Use Based on Quantity, Frequency, and Duration of Use: A Latent Profile Analysis

OBJECTIVES

We identified the patterns of cocaine use during individuals' heaviest use period by considering quantity, frequency, and duration simultaneously and examined the correlates and risk profile for these patterns.

METHODS

Latent profile analysis was conducted among the 3117 individuals who reported lifetime use of cocaine in the National Epidemiologic Survey on Alcohol and Related Conditions-III (NESARC-III) with quantity, frequency, and duration used as indicators. Logistic regression analyses examined factors associated with subtype membership based on patterns of cocaine use and the relationships between these patterns and cocaine use disorder (CocUD) and its severity.

RESULTS

Four patterns were identified: a "low use" class (72.6%), a "moderate use" class (8.2%), a "daily use" class (17.9%), and a "very high quantity use" class (1.3%). Relative to non-Hispanic White and the "low use" class, non-Hispanic Black was associated with increased odds to be in the "moderate use" and "daily use" classes. Higher prevalence of smoking crack cocaine and poly-route use was observed among the "very high quantity use" class relative to other classes; increased risk of using other substances was associated with the "daily use" class. Higher levels of cocaine use were associated with higher risks of CocUD and worse severity compared to the "low use" class.

CONCLUSIONS

People who use cocaine are heterogeneous with different patterns of use and risks of CocUD. Reducing cocaine smoking and poly-route of use should be placed as the same priority as decreasing very high quantity of use in interventions.

Sex differences in the effects of a combined behavioral and pharmacological treatment strategy for cocaine relapse prevention in an animal model of cue exposure therapy

Brief interventions of environmental enrichment (EE) or the glycine transporter-1 inhibitor Org24598 administered with cocaine-cue extinction training were shown previously to inhibit reacquisition of cocaine self-administration in male rats trained to self-administer a moderate 0.3 mg/kg dose of cocaine. Determining how EE and Org24598 synergize in combination in an animal model of cue exposure therapy is novel. Important changes made in this investigation were increasing the cocaine training dose to 1.0 mg/kg and determining sex differences. Adult male and female rats self-administering 1.0 mg/kg cocaine for 35-40 daily sessions exhibited an addiction-like phenotype under a second-order schedule of cocaine delivery and cue presentation. Rats next underwent 6 weekly extinction training sessions for which treatments consisted of EE or NoEE and Vehicle or Org24598 (3.0 mg/kg in males; 3.0 or 7.5 mg/kg in females). Rats then were tested for reacquisition of cocaine self-administration for 15 daily sessions. In males, the combined EE +3.0 mg/kg Org24598 treatment facilitated extinction learning and inhibited reacquisition of cocaine self-administration to a greater extent than no treatment and to individual EE or 3.0 mg/kg Org24598 treatments. In females, EE +7.5 mg/kg Org24598 facilitated extinction learning, but did not inhibit reacquisition of cocaine self-administration. Thus, there were sex differences in the ability of EE + Org24598 administered in conjunction with extinction training to inhibit cocaine relapse in rats exhibiting an addiction-like phenotype. These findings suggest that this multimodal treatment approach might be a feasible option during cue exposure therapy in cocaine-dependent men, but not women.

Prescription psychostimulants for the treatment of stimulant use disorder: a systematic review and meta-analysis

RATIONALE

Agonist-based pharmacologic intervention is an accepted approach in treatment of opioid and tobacco use disorders.

OBJECTIVES

We conducted a systematic review and meta-analysis to evaluate usefulness of an agonist approach as treatment of (psycho)stimulant use disorder (PSUD).

METHODS

We reviewed PubMed/Medline, LILACS, and ClinicalTrials.gov databases searching for randomized, double-blind, placebo-controlled, parallel-design studies evaluating outcomes of individuals treated for cocaine- or amphetamine-type substance use disorder. We combined results of all trials that included the following prescription psychostimulants (PPs): modafinil, methylphenidate, or amphetamines (mixed amphetamine salts, lisdexamphetamine, and dextroamphetamine). The combined sample consisted of 2889 patients. Outcomes of interest included the following: drug abstinence (defined as 2-3 weeks of sustained abstinence and the average maximum days of consecutive abstinence), percentage of drug-negative urine tests across trial, and retention in treatment. We conducted random-effects meta-analyses and assessed quality of evidence using the GRADE system.

RESULTS

Thirty-eight trials were included. Treatment with PPs increases rates of sustained abstinence [risk ratio (RR) = 1.45, 95% confidence interval (CI) = (1.10, 1.92)] and duration of abstinence [mean difference (MD) = 3.34, 95% CI = (1.06, 5.62)] in patients with PSUD, particularly those with cocaine use disorder (very low-quality evidence). Prescription amphetamines were particularly efficacious in promoting sustained abstinence in patients with cocaine use disorder [RR = 2.44, 95% CI = (1.66, 3.58)], and higher doses of PPs were particularly efficacious for treatment of cocaine use disorder [RR = 1.95, 95% CI = (1.38, 2.77)] (moderate-quality evidence). Treatment with prescription amphetamines also yielded more cocaine-negative urines [MD = 8.37%, 95% CI = (3.75, 12.98)]. There was no effect of PPs on the retention in treatment.

CONCLUSION

Prescription psychostimulants, particularly prescription amphetamines given in robust doses, have a clinically significant beneficial effect to promote abstinence in the treatment of individuals with PSUD, specifically the population with cocaine use disorder.