Imagery-based Coping for Cocaine Use Disorder

A pragmatic, 4-week, 4-group, between-subjects, factorial randomised controlled trial conducted at a specialist NHS outpatient addictions clinic and hospital clinical research facility to determine if mental imagery (of past and future positive \[recovery oriented\] and negative \[cocaine aversive\] events) can help reduce cue-induced cocaine craving and cocaine use.

Cocaine, a powerful stimulant drug, is used by 2.2% of people aged 16-59 in England and each year about 150.000 people seek help for cocaine use disorder from the NHS or non-governmental organisations (NGO). There are currently no approved medication-assisted treatments or specific psychosocial interventions for CUD. General counselling is offered by the NHS and NGO addiction services, but this is not particularly effective.

The transition from regular cocaine use to cocaine abuse is often marked by intense episodes (binges), which may last several days and are followed by a 'crash' with no or little use. For many people, repeated administration of cocaine over a short duration of time creates vivid episodic memories of euphoria which can inform future craving content. Craving or strong urges are a distinctive feature of CUD and are often reported as involuntary, distressing and uncontrollable.

Research has demonstrated that craving experiences can be voluntarily evoked or elicited by conditioned drug cues in the environment and internal processes such mood or physical sensations. The associations between cues and use are established through classical and instrumental reward-based conditioning and are important for the development and maintenance of CUD. Enhanced attention to cocaine cues develops and remains heightened for at least six months into abstinence.

Craving-related experiences are informed by memories of intense reward, physical sensations and include pro-drug beliefs, appraisals, expectancies and vivid mental imagery. Drug-imagery is often initially pleasurable and affectively charged and can motivate drug-seeking behaviour. If impeded or delayed, drug imagery highlights a deficit and can be experienced as distressing and intrusive. Treatment of intrusive images has been successful in various psychological disorders using imagery rescripting. Imagery rescripting has recently been used in memory-focused cognitive therapy to help reduce cocaine craving. Reducing intrusive image-induced negative affect through positive imagery is important for relieving psychological distress but there is also evidence that aversive imagery may reduce maladaptive approach behaviours.

This will be a pragmatic, 4-week, 2x2, between-subjects, factorial randomised controlled trial. It will be conducted at a specialist NHS outpatient addictions clinic (Lorraine Hewitt House; LHH) operated by South London and Maudsley NHS Foundation trust (SLaM) and at the NIHR Wellcome Trust King's Clinical Research Facility (CRF) at King's College Hospital.

Informed consenting adult participants will be randomised to one of four conditions:

* future-based (prospective) recovery-oriented imagery;
* future-based (prospective) cocaine-aversive imagery;
* past (autobiographical) recovery-oriented imagery; or
* past (autobiographical) cocaine-aversive imagery.

Participants will undergo a craving induction procedure designed to elicit cue-induced craving. In response to elevated craving, participants will be asked to reduce their craving levels using a mental imagery intervention.

Following the procedure in the research facility, participants will be given a digital audio player to take home. This will contain a recording of the imagery condition they are allocated to. Participants will be asked to listen to this recording each day during a 14-day follow-up, and ad libertatem when experiencing cocaine craving. After 14 days participants will be invited for a follow up conducted at the community addictions clinic.

Eligibility Criteria:
Inclusion Criteria:

* Adult (18 years and over; no upper limit);
* English speaking (to a level sufficient to engage with a psychosocial intervention);
* Current diagnosis for primary CUD alone, with concurrent opiate use disorder or while enrolled in opioid agonist therapy \*
* Self-reported regular use of crack cocaine;
* Stated motivation to reduce or quit cocaine use;

Exclusion Criteria:

* Current post-traumatic stress disorder (PTCI score \>100);
* Suicide attempt in the past 3 months;
* Participants with harmful alcohol consumption (\>50 units per week men; \>35 units women);
* Cocaine hydrochloride (powder form) users; \*\*
* Non-English Speaking;
* Clinically significant on-going medical problems that might make participation unsafe;
* Uncontrolled Mental Health Disorder;
* Severe neurocognitive impairment (Montreal Cognitive Assessment \<17);
* Current enrolment in an addiction treatment related clinical research study