Design and inference for the intent-to-treat principle using adaptive treatment

Contingency management plus acceptance and commitment therapy for initial cocaine abstinence: Results of a sequential multiple assignment randomized trial (SMART)

BACKGROUND

This study tested an adaptive intervention for optimizing abstinence outcomes over phases of treatment for cocaine use disorder using a SMART design. Phase 1 assessed whether 4 weeks of contingency management (CM) improved response with the addition of Acceptance and Commitment Therapy (ACT). Phase 2 assessed pharmacological augmentation with modafinil (MOD) vs. placebo (PLA) for individuals not achieving abstinence during Phase 1.

METHOD

For Phase 1 of treatment, participants (N=118) were randomly allocated to ACT+CM or Drug Counseling (DC+CM), the comparison condition. At week 4, treatment response was defined as the submission of six consecutive cocaine-negative urine drug screens (UDS). Phase 1 non-responders were re-randomized to MOD or PLA as adjunct to their initial treatment. Phase 1 responders continued receiving their initial treatment. Primary outcomes included response rate and proportion of cocaine-negative UDS for Phase 1 and 2. Analyses used Bayesian inference with 80% pre-specified as the posterior probability (PP) threshold constituting moderate evidence that an effect exists.

RESULTS

Phase 1 response was higher in the ACT+CM group (24.5%) compared to the DC+CM group (17.5%; PP = 84.5%). In Phase 2, the proportion of cocaine-negative UDS among Phase 1 responders did not differ by initial treatment (PP = 61.8%) but remained higher overall compared to Phase 1 non-responders (PPs > 99%). No evidence of an effect favoring augmentation with MOD was observed.

DISCUSSION

Adding ACT to CM increased abstinence initiation. Initial responders were more likely to remain abstinent compared to initial non-responders, for whom modafinil was not an effective pharmacotherapy augmentation strategy.

An adaptive design to screen, treat, and retain people with opioid use disorders who use methamphetamine in methadone clinics (STAR-OM): study protocol of a clinical trial

BACKGROUND

Methamphetamine use could jeopardize the current efforts to address opioid use disorder and HIV infection. Evidence-based behavioral interventions (EBI) are effective in reducing methamphetamine use. However, evidence on optimal combinations of EBI is limited. This protocol presents a type-1 effectiveness-implementation hybrid design to evaluate the effectiveness, cost-effectiveness of adaptive methamphetamine use interventions, and their implementation barriers in Vietnam.

METHOD

Design: Participants will be first randomized into two frontline interventions for 12 weeks. They will then be placed or randomized to three adaptive strategies for another 12 weeks. An economic evaluation and an ethnographic evaluation will be conducted alongside the interventions.

PARTICIPANTS

We will recruit 600 participants in 20 methadone clinics.

ELIGIBILITY CRITERIA

(1) age 16+; (2) Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) scores ≥ 10 for methamphetamine use or confirmed methamphetamine use with urine drug screening; (3) willing to provide three pieces of contact information; and (4) having a cell phone.

OUTCOMES

Outcomes are measured at 13, 26, and 49 weeks and throughout the interventions. Primary outcomes include the (1) increase in HIV viral suppression, (2) reduction in HIV risk behaviors, and (3) reduction in methamphetamine use. COVID-19 response: We developed a response plan for interruptions caused by COVID-19 lockdowns to ensure data quality and intervention fidelity.

DISCUSSION

This study will provide important evidence for scale-up of EBIs for methamphetamine use among methadone patients in limited-resource settings. As the EBIs will be delivered by methadone providers, they can be readily implemented if the trial demonstrates effectiveness and cost-effectiveness.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04706624. Registered on 13 January 2021. https://clinicaltrials.gov/ct2/show/NCT04706624.

Race, psychosocial characteristics, and treatment outcomes among individuals undergoing treatment for cannabis use disorder: A latent profile analysis based on preferred method of using cannabis

INTRODUCTION

There are a wide variety of methods for using combustible cannabis which may impact an individual's pattern of use as well as their response to cannabis use disorder (CUD) treatment. Previous research has noted racial/ethnic differences in cannabis users' preferred method of use.

METHOD

The current study examined data from a randomized placebo-controlled trial of a pharmacological intervention for adults with CUD. Latent profile analysis classified participants (N = 302) based on their primary method of combustible cannabis use.

RESULTS

A four profile solution emerged which identified participants who demonstrated 1) Primarily Joint (n = 50), 2) Primarily Blunt (n = 106), 3) Mixed MoU (n = 30), and 4) Primarily Pipe (i.e., pipe or bong; n = 116) use. Profiles were compared on socio-demographic characteristics and racial differences were found among the four latent profiles as well as differences in their level of use. Cannabis users with a preference for joints were more likely to be White as compared to other racial groups. In contrast, a greater proportion of participants with a preference for blunts were African American. The Primarily Joint profile was found to have the highest cannabis relapse rate at 1-month follow-up (94%) which was significantly greater than the Mixed MoU (74%, x² = 5.06, p < .05) and Primarily Pipe (78%, x² = 9.24, p < .01) profiles. Interestingly, there was no difference in 1-Month Follow-up cannabis relapse rates between the Primarily Joint and Blunt profiles (87%, x² = 9.24, p > .05).

CONCLUSIONS

Findings suggest that treatment-seeking individuals who primarily use joints or blunts may face unique challenges that may impact cannabis abstinence. Along with other cannabis-related characteristics, an individual's preferred method of use may represent an important factor to consider in the treatment of CUD.

Psychosocial intervention utilization and substance abuse treatment outcomes in a multisite sample of individuals who use opioids

BACKGROUND

There are several relatively safe and effective FDA-approved medications for Opioid Use Disorder (OUD). Despite the existence of these medications, the rate of returning to opioid use after treatment is relatively high, underscoring the need for continued enhancement of treatments. Adjunctive psychosocial interventions paired with medication have been shown to improve OUD treatment outcomes. However, studies have yet to conclusively examine the distinct effects of the most widely utilized psychosocial treatment modalities. The current study will investigate the relationship between individual counseling, group therapy, and 12-Step participation and illicit opioid abstinence at the end of treatment, 1 and 3 months after treatment.

METHOD

A secondary analysis was conducted with data from a sample of 570 individuals diagnosed with OUD who were recruited from eight substance abuse treatment centers in the United States. Participants were enrolled in a two-group randomized, controlled trial testing buprenorphine-naloxone versus extended-release naltrexone for OUD. A two-level hierarchical linear growth model was used to examine the effects of individual counseling, group therapy, and 12-Step participation on illicit opioid abstinence (urinanalyses) 1- and 3-months post-treatment.

RESULTS

Hours of individual counseling and 12-Step participation significantly predicted abstinence at follow-up (p < .001, b = -0.59, 95% CI [0.42, 0.74]; p < .01, b = -0.05, 95% CI [0.92, 0.98]). There was a significant interaction between individual counseling and 12-Step participation (p < .01, b = -0.06, 95% CI [1.02, 1.10]). Additionally, participant age and employment status were significant predictors of illicit opioid abstinence (p < .01, b = -0.02, 95% CI [0.97, 0.99]; p < .01, b = -0.38, 95% CI [0.52, 0.90]). Hours of group therapy was not found to significantly predict illicit opioid abstinence.

CONCLUSIONS

Findings suggest that greater levels of individual therapy and 12-Step participation may be beneficial for individuals receiving medication treatment for OUD.