Positive reinforcement targeting abstinence in substance misuse (PRAISe): Study protocol for a Cluster RCT & process evaluation of contingency management

The Cost-Effectiveness of Financial Incentives to Achieve Heroin Abstinence in Individuals With Heroin Use Disorder Starting New Treatment Episodes: A Cluster Randomized Trial-Based Economic Evaluation

OBJECTIVES

Cost-effectiveness analysis of two 12-week contingency management (CM) schedules targeting heroin abstinence or attendance at weekly keyworker appointments for opioid agonist treatment compared with treatment as usual (TAU).

METHODS

A cost-effectiveness analysis was conducted alongside a cluster randomized trial of 552 patients from 34 clusters (drug treatment clinics) randomly allocated 1:1:1 to opioid agonist treatment plus weekly keyworker appointments with (1) CM targeted at heroin abstinence (CM abstinence), (2) CM targeted at on-time attendance at weekly appointments (CM attendance), or (3) no CM (TAU). The primary cost-effectiveness analysis at 24 weeks after randomization took a societal cost perspective with effects measured in heroin-negative urine samples.

RESULTS

At 24 weeks, mean differences in weekly heroin-negative urine results compared with TAU were 0.252 (95% confidence interval [CI] -0.397 to 0.901) for CM abstinence and 0.089 (95% CI -0.223 to 0.402) for CM attendance. Mean differences in costs were £2562 (95% CI £32-£5092) for CM abstinence and £317 (95% CI -£882 to £1518) for CM attendance. Incremental cost-effectiveness ratios were £10 167 per additional heroin-free urine for CM abstinence and £3562 for CM attendance with low probabilities of cost-effectiveness of 3.5% and 36%, respectively. Results were sensitive to timing of follow-up for CM attendance, which dominated TAU (better outcomes, lower costs) at 12 weeks, with an 88.4% probability of being cost-effective. Probability of cost-effectiveness remained low for CM abstinence (8.6%).

CONCLUSIONS

Financial incentives targeted toward heroin abstinence and treatment attendance were not cost-effective over the 24-week follow-up. Nevertheless, CM attendance was cost-effective over the treatment period (12 weeks), when participants were receiving keyworker appointments and incentives.

Using a pragmatically adapted, low-cost contingency management intervention to promote heroin abstinence in individuals undergoing treatment for heroin use disorder in UK drug services (PRAISE): a cluster randomised trial

INTRODUCTION

Most individuals treated for heroin use disorder receive opioid agonist treatment (OAT)(methadone or buprenorphine). However, OAT is associated with high attrition and persistent, occasional heroin use. There is some evidence for the effectiveness of contingency management (CM), a behavioural intervention involving modest financial incentives, in encouraging drug abstinence when applied adjunctively with OAT. UK drug services have a minimal track record of applying CM and limited resources to implement it. We assessed a CM intervention pragmatically adapted for ease of implementation in UK drug services to promote heroin abstinence among individuals receiving OAT.

DESIGN

Cluster randomised controlled trial.

SETTING AND PARTICIPANTS

552 adults with heroin use disorder (target 660) enrolled from 34 clusters (drug treatment clinics) in England between November 2012 and October 2015.

INTERVENTIONS

Clusters were randomly allocated 1:1:1 to OAT plus 12× weekly appointments with: (1) CM targeted at opiate abstinence at appointments (CM Abstinence); (2) CM targeted at on-time attendance at appointments (CM Attendance); or (3) no CM (treatment as usual; TAU). Modifications included monitoring behaviour weekly and fixed incentives schedule.

MEASUREMENTS

Primary outcome: heroin abstinence measured by heroin-free urines (weeks 9-12).

SECONDARY OUTCOMES

heroin abstinence 12 weeks after discontinuation of CM (weeks 21-24); attendance; self-reported drug use, physical and mental health.

RESULTS

CM Attendance was superior to TAU in encouraging heroin abstinence. Odds of a heroin-negative urine in weeks 9-12 was statistically significantly greater in CM Attendance compared with TAU (OR=2.1; 95% CI 1.1 to 3.9; p=0.030). CM Abstinence was not superior to TAU (OR=1.6; 95% CI 0.9 to 3.0; p=0.146) or CM Attendance (OR=1.3; 95% CI 0.7 to 2.4; p=0.438) (not statistically significant differences). Reductions in heroin use were not sustained at 21-24 weeks. No differences between groups in self-reported heroin use.

CONCLUSIONS

A pragmatically adapted CM intervention for routine use in UK drug services was moderately effective in encouraging heroin abstinence compared with no CM only when targeted at attendance. CM targeted at abstinence was not effective.

TRIAL REGISTRATION NUMBER

ISRCTN 01591254.

Telephone delivered incentives for encouraging adherence to supervised methadone consumption (TIES): Study protocol for a feasibility study for an RCT of clinical and cost effectiveness

The majority of people receiving treatment for their heroin addiction, are prescribed methadone; for which there is an extensive evidence base. When treatment starts, people take their daily dose of methadone under supervision at a community pharmacy. Supervision guarantees methadone is taken as directed by the individual for whom it has been prescribed, helps to ensure individuals take their correct dose every day, and safeguards against diversion and overdose. However, individuals often fail to attend the pharmacy to take their methadone. Each missed dose is of concern. If a patient misses their daily dose of methadone, they will start to experience opiate withdrawal and cravings and are more likely to use heroin. If they miss three days dose, there are concerns that they may lose tolerance to the drug and may be at risk of overdose when the next dose is taken. Hence there is an urgent need to develop effective interventions for medication adherence. Research suggests that incentive-based medication adherence interventions may be very effective, but there are few controlled trials and the provision of incentives requires time and organisational systems which can be challenging in pharmacies. The investigators have developed the technology to deliver incentives by mobile telephone. This cluster randomised trial will test the feasibility of conducting a future trial evaluating the clinical and cost effectiveness of using telephone delivered incentives (praise and modest financial rewards via text messaging) to encourage adherence with supervised consumption of methadone in community pharmacies. Three drug services (each with two or three community pharmacies supervising methadone consumption that will enrol 20 individuals, a total of 60 participants) will be recruited and randomly allocated to deliver either i) telephone delivered incentives, ii) telephone delivered reminders or iii) no telephone system. Acceptability, recruitment, follow-up, and suitable measures of clinical and cost effectiveness will be assessed. Findings from this feasibility study will be assessed against stated progression criteria and used to inform a future confirmatory trial of the clinical and cost effectiveness of telephone delivered incentives to encourage medication adherence.

Trial registration

ISRCTN58958179 (retrospectively registered).